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1 
2 C and C++ XML Data Bindings {#mainpage}
3 ===========================
4 
5 [TOC]
6 
7 Introduction {#intro}
8 ============
9 
10 This is a detailed overview of the gSOAP C and C++ XML data bindings and
11 discussed the advantages, concepts, usage, and implementation. At the end of
12 this document two examples are given to illustrate the application of XML data
13 bindings.
14 
15 The first simple example `address.cpp` shows how to use wsdl2h to bind an XML
16 schema to C++. The C++ application reads and writes an XML file into and from
17 a C++ "address book" data structure. The C++ data structure is an STL vector
18 of address objects.
19 
20 The second example `graph.cpp` shows how XML is serialized as a tree, digraph,
21 and cyclic graph. The digraph and cyclic graph serialization rules are similar
22 to SOAP 1.1/1.2 encoded multi-ref elements with id-ref attributes to link
23 elements through IDREF XML references, creating a an XML graph with pointers to
24 XML nodes.
25 
26 The major advantage of XML data bindings is that your application data is
27 always **type safe** in C and C++ by binding XML schema types to C/C++ types.
28 So integers in XML are bound to C integers, strings in XML are bound to C or
29 C++ strings, complex types in XML are bound to C structs or C++ classes, and so
30 on. The structured data you create and accept will fit the data model and is
31 **static type safe**. In other words, by leveraging strong typing in C/C++,
32 your XML data meets **XML validation requirements** and satisfies **XML
33 interoperability requirements**.
34 
35 The gSOAP data bindings are more powerful than simply representing C/C++ data
36 in XML. In fact, the tools implement **true serialization** of C/C++ data in
37 XML, including the serialization of cyclic graph structures. The gSOAP tools
38 also generate routines for deep copying and deep deletion of C/C++ data
39 structures to simplify memory management. In addition, C/C++ structures are
40 deserialized into managed memory, managed by the gSOAP `soap` context.
41 
42 These examples demonstrate XML data bindings only for relatively simple data
43 structures and types. The gSOAP tools support more than just these type of
44 structures to serialize in XML. There are practically no limits to
45 enable XML serialization of C and C++ types.
46 
47 Support for XML schema components is unlimited. The wsdl2h tool maps schemas
48 to C and C++ using built-in intuitive mapping rules, while allowing the
49 mappings to be customized using a `typemap.dat` file with mapping instructions
50 for wsdl2h.
51 
52 The information in this document is applicable to gSOAP 2.8.26 and later
53 versions that support C++11 features. However, C++11 is not required to use
54 this material and the examples included, unless we need smart pointers and
55 scoped enumerations. While most of the examples in this document are given in
56 C++, the concepts also apply to C with the exception of containers, smart
57 pointers, classes and their methods. None of these exceptions limit the use of
58 the gSOAP tools for C in any way.
59 
60 The data binding concepts described in this document were first envisioned in
61 1999 by Prof. Robert van Engelen at the Florida State University. An
62 implementation was created in 2000, named "stub/skeleton compiler". The first
63 articles on its successor version "gSOAP" appeared in 2002. The principle of
64 mapping XSD components to C/C++ types and vice versa is now widely adopted in
65 systems and programming languages, including Java web services and by C# WCF.
66 
67 We continue to be committed to our goal to empower C/C++ developers with
68 powerful autocoding tools for XML. Our commitment started in the very early
69 days of SOAP by actively participating in
70 [SOAP interoperability testing](http://www.whitemesa.com/interop.htm),
71 participating in the development and testing of the
72 [W3C XML Schema Patterns for Databinding Interoperability](http://www.w3.org/2002/ws/databinding),
73 and continues by contributing to the development of
74 [OASIS open standards](https://www.oasis-open.org) in partnership with leading
75 IT companies.
76 
77 Mapping WSDL and XML schemas to C/C++ {#tocpp}
78 =====================================
79 
80 To convert WSDL and XML schemas (XSD files) to code, use the wsdl2h command to
81 generate the data binding interface code that is saved to a special gSOAP
82 header file with WSDL service declarations and the data binding interface:
83 
84  wsdl2h [options] -o file.h ... XSD and WSDL files ...
85 
86 This command converts WSDL and XSD files to C++ (or pure C with wsdl2h option
87 `-c`) and saves the data binding interface to a gSOAP header file `file.h` that
88 uses familiar C/C++ syntax extended with `//gsoap` [directives](#directives)
89 and annotations. Notational conventions are used in the data binding interface
90 to declare serializable C/C++ types and functions for Web service operations.
91 
92 The WSDL 1.1/2.0, SOAP 1.1/1.2, and XSD 1.0/1.1 standards are supported by the
93 gSOAP tools. In addition, the most popular WS specifications are also
94 supported, including WS-Addressing, WS-ReliableMessaging, WS-Discovery,
95 WS-Security, WS-Policy, WS-SecurityPolicy, and WS-SecureConversation.
96 
97 This document focusses on XML data bindings. XML data bindings for C/C++ bind
98 XML schema types to C/C++ types. So integers in XML are bound to C integers,
99 strings in XML are bound to C or C++ strings, complex types in XML are bound to
100 C structs or C++ classes, and so on.
101 
102 A data binding is dual. Either you start with WSDLs and/or XML schemas that
103 are mapped to equivalent C/C++ types, or you start with C/C++ types that are
104 mapped to XSD types. Either way, the end result is that you can serialize
105 C/C++ types in XML such that your XML is an instance of XML schema(s) and is
106 validated against these schema(s).
107 
108 This covers all of the following standard XSD components with their optional
109 attributes and properties:
110 
111 | XSD Component | Attributes and Properties |
112 | -------------- | ------------------------------------------------------------------------------------------------------------------- |
113 | schema | targetNamespace, version, elementFormDefault, attributeFormDefault, defaultAttributes |
114 | attribute | name, ref, type, use, default, fixed, form, targetNamespace, wsdl:arrayType |
115 | element | name, ref, type, default, fixed, form, nillable, abstract, substitutionGroup, minOccurs, maxOccurs, targetNamespace |
116 | simpleType | name |
117 | complexType | name, abstract, mixed, defaultAttributesApply |
118 | all | |
119 | choice | minOccurs, maxOccurs |
120 | sequence | minOccurs, maxOccurs |
121 | group | name, ref, minOccurs, maxOccurs |
122 | attributeGroup | name, ref |
123 | any | minOccurs, maxOccurs |
124 | anyAttribute | |
125 
126 And also the following standard XSD directives are covered:
127 
128 | Directive | Description |
129 | ---------- | ---------------------------------------------------------- |
130 | import | Imports a schema into the importing schema for referencing |
131 | include | Include schema component definitions into a schema |
132 | override | Override by replacing schema component definitions |
133 | redefine | Extend or restrict schema component definitions |
134 | annotation | Annotates a component |
135 
136 The XSD facets and their mappings to C/C++ are:
137 
138 | XSD Facet | Maps to |
139 | -------------- | ------------------------------------------------------------------------------------------- |
140 | enumeration | `enum` |
141 | simpleContent | class/struct wrapper with `__item` member |
142 | complexContent | class/struct |
143 | list | `enum*` bitmask (`enum*` enumerates up to 64 bit masks) |
144 | extension | class/struct inheritance/extension |
145 | restriction | `typedef` and class/struct inheritance/redeclaration |
146 | length | `typedef` with restricted content length annotation |
147 | minLength | `typedef` with restricted content length annotation |
148 | maxLength | `typedef` with restricted content length annotation |
149 | minInclusive | `typedef` with numerical value range restriction annotation |
150 | maxInclusive | `typedef` with numerical value range restriction annotation |
151 | minExclusive | `typedef` with numerical value range restriction annotation |
152 | maxExclusive | `typedef` with numerical value range restriction annotation |
153 | precision | `typedef` with pattern annotation (pattern used for output, but input is not validated) |
154 | scale | `typedef` with pattern annotation (pattern used for output, but input is not validated) |
155 | totalDigits | `typedef` with pattern annotation (pattern used for output, but input is not validated) |
156 | fractionDigits | `typedef` with pattern annotation (pattern used for output, but input is not validated) |
157 | pattern | `typedef` with pattern annotation (define `soap::fsvalidate` callback to validate patterns) |
158 | union | string with union of values
159 
160 All primitive XSD types are supported, including but not limited to the
161 following XSD types:
162 
163 | XSD Type | Maps to |
164 | ---------------- | --------------------------------------------------------------------------------- |
165 | any/anyType | `_XML` string with literal XML content (or enable DOM with wsdl2h option `-d`) |
166 | anyURI | string (i.e. `char*`, `wchar_t*`, `std::string`, `std::wstring`) |
167 | string | string (i.e. `char*`, `wchar_t*`, `std::string`, `std::wstring`) |
168 | boolean | `bool` (C++) or `enum xsd__boolean` (C) |
169 | byte | `char` (i.e. `int8_t`) |
170 | short | `short` (i.e. `int16_t`) |
171 | int | `int` (i.e. `int32_t`) |
172 | long | `LONG64` (i.e. `long long` and `int64_t`) |
173 | unsignedByte | `unsigned char` (i.e. `uint8_t`) |
174 | unsignedShort | `unsigned short` (i.e. `uint16_t`) |
175 | unsignedInt | `unsigned int` (i.e. `uint32_t`) |
176 | unsignedLong | `ULONG64` (i.e. `unsigned long long` and `uint64_t`) |
177 | float | `float` |
178 | double | `double` |
179 | integer | string or `#import "custom/int128.h"` to use 128 bit `xsd__integer` |
180 | decimal | string or `#import "custom/long_double.h"` to use `long double` |
181 | precisionDecimal | string |
182 | duration | string or `#import "custom/duration.h"` to use 64 bit `xsd__duration` |
183 | dateTime | `time_t` or `#import "custom/struct_tm.h"` to use `struct tm` for `xsd__dateTime` |
184 | time | string or `#import "custom/long_time.h"` to use 64 bit `xsd__time` |
185 | date | string or `#import "custom/struct_tm_date.h"` to use `struct tm` for `xsd__date` |
186 | hexBinary | special class/struct `xsd__hexBinary` |
187 | base64Bianry | special class/struct `xsd__base64Binary` |
188 | QName | `_QName` string (URI normalization rules are applied) |
189 
190 All other primitive XSD types not listed above are mapped to strings, by
191 wsdl2h generating a typedef to string for these types. For example,
192 `xsd:token` is bound to a C++ or C string:
193 
194 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
195  typedef std::string xsd__token; // C++
196  typedef char *xsd__token; // C (wsdl2h option -c)
197 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
198 
199 This associates a compatible value space to the type with the appropriate XSD
200 type name used by the soapcpp2-generated serializers.
201 
202 It is possible to remap types by adding the appropriate mapping rules to
203 `typemap.dat` as we will explain in more detail in the next section.
204 
205 Imported custom serializers are intended to extend the C/C++ type bindings when
206 the default binding to string is not satisfactory to your taste and if the
207 target platform supports these C/C++ types. To add custom serializers to
208 `typemap.dat` for wsdl2h, see [adding custom serializers](#custom) below.
209 
210 Using typemap.dat to customize data bindings {#typemap}
211 ============================================
212 
213 Use a `typemap.dat` file to redefine namespace prefixes and to customize type
214 bindings for the the generated header files produced by the wsdl2h tool. The
215 `typemap.dat` is the default file processed by wsdl2h. Use wsdl2h option `-t`
216 to specify a different file.
217 
218 Declarations in `typemap.dat` can be broken up over multiple lines by
219 continuing on the next line by ending each line to be continued with a
220 backslash `\`. The limit is 4095 characters per line, whether the line is
221 broken up or not.
222 
223 XML namespace bindings {#typemap1}
224 ----------------------
225 
226 The wsdl2h tool generates C/C++ type declarations that use `ns1`, `ns2`, etc.
227 as schema-binding URI prefixes. These default prefixes are generated somewhat
228 arbitrarily for each schema targetNamespace URI, meaning that their ordering
229 may change depending on the WSDL and XSD order of processing with wsdl2h.
230 
231 Therefore, it is **strongly recommended** to declare your own prefix for each
232 schema URI in `typemap.dat` to reduce maintaince effort of your code. This
233 is more robust when anticipating possible changes of the schema(s) and/or the
234 binding URI(s) and/or the tooling algorithms.
235 
236 The first and foremost important thing to do is to define prefix-URI bindings
237 for our C/C++ code by adding the following line(s) to our `typemap.dat` or make
238 a copy of this file and add the line(s) that bind our choice of prefix name to
239 each URI:
240 
241  prefix = "URI"
242 
243 For example, to use `g` as a prefix for the "urn:graph" XML namespace:
244 
245  g = "urn:graph"
246 
247 This produces `g__name` C/C++ type names that are bound to the "urn:graph"
248 schema by association of `g` to the generated C/C++ types.
249 
250 This means that `<g:name xmlns:g="urn:graph">` is parsed as an instance of a
251 `g__name` C/C++ type. Also `<x:name xmlns:x="urn:graph">` parses as an
252 instance of `g__name`, because the prefix `x` has the same URI value
253 `urn:graph`. Prefixes in XML have local scopes (like variables in a block).
254 
255 The first run of wsdl2h will reveal the XML namespace URIs, so you do not need
256 to search WSDLs and XSD files for all of the target namespaces. Just copy them
257 from the generated header file after the first run into `typemap.dat` for
258 editing.
259 
260 @note Only define a namespace prefix once in `typemap.dat`. That is, do not
261 use the same prefix for multiple XML namespace URIs. This is to avoid
262 namespace conflicts that may cause failed builds and failures in XML parsing
263 and validation.
264 
265 XSD type bindings {#typemap2}
266 -----------------
267 
268 Custom C/C++ type bindings can be declared in `typemap.dat` to associate C/C++
269 types with specific schema types. These type bindings have four parts:
270 
271  prefix__type = declaration | use | ptruse
272 
273 where
274 
275 - `prefix__type` is the schema type to be customized (the `prefix__type` name
276  uses the common double underscore naming convention);
277 - `declaration` declares the C/C++ type in the wsdl2h-generated header file.
278  This part can be empty if no explicit declaration is needed;
279 - `use` is an optional part that specifies how the C/C++ type is used in the
280  code. When omitted, it is the same as `prefix__type`;
281 - `ptruse` is an optional part that specifies how the type is used as a pointer
282  type. By default it is the `use` type name with a `*` or C++11
283  `std::shared_ptr<>` when enabled (see further below). If `use` is already a
284  pointer type by the presence of a `*` in the `use` part, then the default
285  `ptruse` type is the same as the `use` type (that is, no double pointer `**`
286  will be created in this case).
287 
288 For example, to map `xsd:duration` to a `long long` (`LONG64`) type that holds
289 millisecond duration values, we can use the custom serializer declared in
290 `custom/duration.h` by adding the following line to `typemap.dat`:
291 
292  xsd__duration = #import "custom/duration.h"
293 
294 Here, we omitted the second and third parts, because `xsd__duration` is the
295 name that wsdl2h uses for this type in our generated code so we should leave
296 the `use` part unspecified. The third part is omitted to let wsdl2h use
297 `xsd__duration *` for pointers or `std::shared_ptr<xsd__duration>` if smart
298 pointers are enabled.
299 
300 To map `xsd:string` to `wchar_t*` wide strings:
301 
302  xsd__string = | wchar_t* | wchar_t*
303 
304 Note that the first part is empty, because `wchar_t` is a C type and does not
305 need to be declared. A `ptruse` part is also defined in this example, but does
306 not need to be because the `use` part `wchar_t*` is already a pointer.
307 
308 When the auto-generated declaration should be preserved but the `use` or
309 `ptruse` parts replaced, then we use an ellipsis for the declaration part:
310 
311  prefix__type = ... | use | ptruse
312 
313 This is useful to map schema polymorphic types to C types for example, where we
314 need to be able to both handle a base type and its extensions as per schema
315 extensibility. Say we have a base type called ns:base that is extended, then we
316 can remap this to a C type that permits referening the extended types via a
317 `void*` as follows:
318 
319  ns__base = ... | int __type_base; void*
320 
321 such that `__type_base` and `void*` will be used to (de)serialize any data
322 type, including base and its derived types. The `__type_base` integer is set
323 to a `SOAP_TYPE_T` value to indicate what type of data the `void*` pointer
324 points to.
325 
326 Custom serializers for XSD types {#custom}
327 --------------------------------
328 
329 In the previous part we saw how a custom serializer is used to bind
330 `xsd:duration` to a `long long` (`LONG64` or `int64_t`) type to store millisecond
331 duration values:
332 
333  xsd__duration = #import "custom/duration.h"
334 
335 The `xsd__duration` type is an alias of `long long` (`LONG64` or `int64_t`).
336 
337 While wsdl2h will use this binding declared in `typemap.dat` automatically, you
338 will also need to compile `custom/duration.c`. Each custom serializer has a
339 header file and an implementation file written in C. You can compile these in
340 C++ (rename files to `.cpp` if needed).
341 
342 We will discuss the custom serializers that are available to you.
343 
344 ### xsd:integer {#custom-1}
345 
346 The wsdl2h tool maps `xsd:integer` to a string by default. To map `xsd:integer` to
347 the 128 bit big int type `__int128_t`:
348 
349  xsd__integer = #import "custom/int128.h"
350 
351 The `xsd__integer` type is an alias of `__int128_t`.
352 
353 @warning Beware that the `xsd:integer` value space of integers is in principle
354 unbounded and values can be of arbitrary length. A value range fault
355 `SOAP_TYPE` (value exceeds native representation) or `SOAP_LENGTH` (value
356 exceeds range bounds) will be thrown by the deserializer if the value is out of
357 range.
358 
359 Other XSD integer types that are restrictions of `xsd:integer`, are
360 `xsd:nonNegativeInteger` and `xsd:nonPositiveInteger`, which are further restricted
361 by `xsd:positiveInteger` and `xsd:negativeInteger`. To bind these types to
362 `__int128_t` add the following definitions to `typemap.dat`:
363 
364  xsd__nonNegativeInteger = typedef xsd__integer xsd__nonNegativeInteger 0 : ;
365  xsd__nonPositiveInteger = typedef xsd__integer xsd__nonPositiveInteger : 0 ;
366  xsd__positiveInteger = typedef xsd__integer xsd__positiveInteger 1 : ;
367  xsd__negativeInteger = typedef xsd__integer xsd__negativeInteger : -1 ;
368 
369 Or simply uncomment these definitions in `typemap.dat` when you are using the
370 latest gSOAP releases.
371 
372 @note If `__int128_t` 128 bit integers are not supported on your platform and if it
373 is certain that `xsd:integer` values are within 64 bit value bounds for your
374 application's use, then you can map this type to `LONG64`:
375 
376  xsd__integer = typedef LONG64 xsd__integer;
377 
378 @note Again, a value range fault `SOAP_TYPE` or `SOAP_LENGTH` will be thrown by
379 the deserializer if the value is out of range.
380 
381 After running wsdl2h and soapcpp2, compile `custom/int128.c` with your project.
382 
383 @see Section [numerical types](#toxsd5).
384 
385 ### xsd:decimal {#custom-2}
386 
387 The wsdl2h tool maps `xsd:decimal` to a string by default. To map `xsd:decimal` to
388 extended precision floating point:
389 
390  xsd__decimal = #import "custom/long_double.h" | long double
391 
392 By contrast to all other custom serializers, this serializer enables `long
393 double` natively without requiring a new binding name (`xsd__decimal` is NOT
394 defined).
395 
396 If your system supports `<quadmath.h>` quadruple precision floating point
397 `__float128`, you can map `xsd:decimal` to `xsd__decimal` that is an alias of
398 `__float128`:
399 
400  xsd__decimal = #import "custom/float128.h"
401 
402 @warning Beware that `xsd:decimal` is in principle a decimal value with arbitraty
403 lengths. A value range fault `SOAP_TYPE` will be thrown by the deserializer if
404 the value is out of range.
405 
406 In the XML payload the special values `INF`, `-INF`, `NaN` represent plus or
407 minus infinity and not-a-number, respectively.
408 
409 After running wsdl2h and soapcpp2, compile `custom/long_double.c` with your
410 project.
411 
412 @see Section [numerical types](#toxsd5).
413 
414 ### xsd:dateTime {#custom-3}
415 
416 The wsdl2h tool maps `xsd:dateTime` to `time_t` by default.
417 
418 The trouble with `time_t` when represented as 32 bit `long` integers is that it
419 is limited to dates between 1970 and 2038. A 64 bit `time_t` is safe to use if
420 the target platform supports it, but lack of 64 bit `time_t` portability may
421 still cause date range issues.
422 
423 For this reason `struct tm` should be used to represent wider date ranges. This
424 custom serializer avoids using date and time information in `time_t`. You get
425 the raw date and time information. You only lose the day of the week
426 information. It is always Sunday (`tm_wday=0`).
427 
428 To map `xsd:dateTime` to `xsd__dateTime` which is an alias of `struct tm`:
429 
430  xsd__dateTime = #import "custom/struct_tm.h"
431 
432 If the limited date range of `time_t` is not a problem but you want to increase
433 the time precision with fractional seconds, then we suggest to map `xsd:dateTime`
434 to `struct timeval`:
435 
436  xsd__dateTime = #import "custom/struct_timeval.h"
437 
438 If the limited date range of `time_t` is not a problem but you want to use the
439 C++11 time point type `std::chrono::system_clock::time_point` (which internally
440 uses `time_t`):
441 
442  xsd__dateTime = #import "custom/chrono_time_point.h"
443 
444 Again, we should make sure that the dates will not exceed the date range when
445 using the default `time_t` binding for `xsd:dateTime` or when binding
446 `xsd:dateTime` to `struct timeval` or to `std::chrono::system_clock::time_point`.
447 These are safe to use in applications that use `xsd:dateTime` to record date
448 stamps within a given window. Otherwise, we recommend the `struct tm` custom
449 serializer.
450 
451 After running wsdl2h and soapcpp2, compile `custom/struct_tm.c` with your
452 project.
453 
454 You could even map `xsd:dateTime` to a plain string (use `char*` with C and
455 `std::string` with C++). For example:
456 
457  xsd__dateTime = | char*
458 
459 @see Section [date and time types](#toxsd7).
460 
461 ### xsd:date {#custom-4}
462 
463 The wsdl2h tool maps `xsd:date` to a string by default. We can map `xsd:date` to
464 `struct tm`:
465 
466  xsd__date = #import "custom/struct_tm_date.h"
467 
468 The `xsd__date` type is an alias of `struct tm`. The serializer ignores the
469 time part and the deserializer only populates the date part of the struct,
470 setting the time to 00:00:00. There is no unreasonable limit on the date range
471 because the year field is stored as an integer (`int`).
472 
473 After running wsdl2h and soapcpp2, compile `custom/struct_tm_date.c` with your
474 project.
475 
476 @see Section [date and time types](#toxsd7).
477 
478 ### xsd:time {#custom-5}
479 
480 The wsdl2h tool maps `xsd:time` to a string by default. We can map `xsd:time` to
481 an `unsigned long long` (`ULONG64` or `uint64_t`) integer with microsecond time
482 precision:
483 
484  xsd__time = #import "custom/long_time.h"
485 
486 This type represents 00:00:00.000000 to 23:59:59.999999, from `0` to an upper
487 bound of `86399999999`. A microsecond resolution means that a 1 second
488 increment requires an increment of 1000000 in the integer value. The serializer
489 adds a UTC time zone.
490 
491 After running wsdl2h and soapcpp2, compile `custom/long_time.c` with your
492 project.
493 
494 @see Section [date and time types](#toxsd7).
495 
496 ### xsd:duration {#custom-6}
497 
498 The wsdl2h tool maps `xsd:duration` to a string by default, unless `xsd:duration`
499 is mapped to a `long long` (`LONG64` or `int64_t`) type with with millisecond
500 (ms) time duration precision:
501 
502  xsd__duration = #import "custom/duration.h"
503 
504 The `xsd__duration` type is a 64 bit signed integer that can represent
505 106,751,991,167 days forwards (positive) and backwards (negative) in time in
506 increments of 1 ms (1/1000 of a second).
507 
508 Rescaling of the duration value by may be needed when adding the duration value
509 to a `time_t` value, because `time_t` may or may not have a seconds resolution,
510 depending on the platform and possible changes to `time_t`.
511 
512 Rescaling is done automatically when you add a C++11 `std::chrono::nanoseconds`
513 value to a `std::chrono::system_clock::time_point` value. To use
514 `std::chrono::nanoseconds` as `xsd:duration`:
515 
516  xsd__duration = #import "custom/chrono_duration.h"
517 
518 This type can represent 384,307,168 days (2^63 nanoseconds) forwards and
519 backwards in time in increments of 1 ns (1/1,000,000,000 of a second).
520 
521 Certain observations with respect to receiving durations in years and months
522 apply to both of these serializer decoders for `xsd:duration`.
523 
524 After running wsdl2h and soapcpp2, compile `custom/duration.c` with your
525 project.
526 
527 @see Section [time duration types](#toxsd8).
528 
529 Custom Qt serializers for XSD types {#qt}
530 -----------------------------------
531 
532 The gSOAP distribution includes several custom serializers for Qt types. Also
533 Qt container classes are supported, see
534 [the built-in typemap.dat variables $CONTAINER and $POINTER](#typemap5).
535 
536 This feature requires gSOAP 2.8.34 or higher and Qt 4.8 or higher.
537 
538 Each Qt custom serializer has an interface header file for soapcpp2 and a C++
539 implementation file to be compiled with your project.
540 
541 Other Qt primitive types that are Qt typedefs of C/C++ types do not require a
542 custom serializer.
543 
544 ### xsd:string {#qt-1}
545 
546 To use Qt strings instead of C++ strings, add the following definition to
547 `typemap.dat`:
548 
549  xsd__string = #import "custom/qstring.h"
550 
551 After running wsdl2h and soapcpp2, compile `custom/qstring.cpp` with your
552 project.
553 
554 ### xsd:base64Binary {#qt-2}
555 
556 To use Qt byte arrays for `xsd:base64Binary` instead of the
557 `xsd__base64Binary` class, add the following definition to `typemap.dat`:
558 
559  xsd__base64Binary = #import "custom/qbytearray_base64.h"
560 
561 After running wsdl2h and soapcpp2, compile `custom/qbytearray_base64.cpp` with
562 your project.
563 
564 ### xsd:hexBinary {#qt-3}
565 
566 To use Qt byte arrays for `xsd:hexBinary` instead of the `xsd__base64Binary`
567 class, add the following definition to `typemap.dat`:
568 
569  xsd__hexBinary = #import "custom/qbytearray_hex.h"
570 
571 After running wsdl2h and soapcpp2, compile `custom/qbytearray_hex.cpp` with
572 your project.
573 
574 ### xsd:dateTime {#qt-4}
575 
576 To use Qt QDateTime for `xsd:dateTime`, add the following definition to
577 `typemap.dat`:
578 
579  xsd__dateTime = #import "custom/datetime.h"
580 
581 After running wsdl2h and soapcpp2, compile `custom/qdatetime.cpp` with
582 your project.
583 
584 ### xsd:date {#qt-5}
585 
586 To use Qt QDate for `xsd:date`, add the following definition to
587 `typemap.dat`:
588 
589  xsd__date = #import "custom/qdate.h"
590 
591 After running wsdl2h and soapcpp2, compile `custom/qdate.cpp` with your
592 project.
593 
594 ### xsd:time {#qt-6}
595 
596 To use Qt QDate for `xsd:time`, add the following definition to
597 `typemap.dat`:
598 
599  xsd__time = #import "custom/qtime.h"
600 
601 After running wsdl2h and soapcpp2, compile `custom/qtime.cpp` with your
602 project.
603 
604 Class/struct member additions {#typemap3}
605 -----------------------------
606 
607 All generated classes and structs can be augmented with additional
608 members such as methods, constructors and destructors, and private members:
609 
610  prefix__type = $ member-declaration
611 
612 For example, we can add method declarations and private members to a class, say
613 `ns__record` as follows:
614 
615  ns__record = $ ns__record(const ns__record &); // copy constructor
616  ns__record = $ void print(); // a print method
617  ns__record = $ private: int status; // a private member
618 
619 Note that method declarations cannot include any code, because soapcpp2's input
620 permits only type declarations, not code.
621 
622 Replacing XSD types by equivalent alternatives {#typemap4}
623 ----------------------------------------------
624 
625 Type replacements can be given to replace one type entirely with another given
626 type:
627 
628  prefix__type1 == prefix__type2
629 
630 This replaces all `prefix__type1` by `prefix__type2` in the wsdl2h output.
631 
632 @warning Do not agressively replace types, because this can cause XML
633 validation to fail when a value-type mismatch is encountered in the XML input.
634 Therefore, only replace similar types with other similar types that are wider
635 (e.g. `short` by `int` and `float` by `double`).
636 
637 The built-in typemap.dat variables $CONTAINER and $POINTER {#typemap5}
638 ----------------------------------------------------------
639 
640 The `typemap.dat` `$CONTAINER` variable defines the container to emit in the
641 generated declarations, which is `std::vector` by default. For example, to emit
642 `std::list` as the container in the wsdl2h-generated declarations:
643 
644  $CONTAINER = std::list
645 
646 The `typemap.dat` `$POINTER` variable defines the smart pointer to emit in the
647 generated declarations, which replaces the use of `*` pointers. For example:
648 
649  $POINTER = std::shared_ptr
650 
651 Not all pointers in the generated output can be replaced by smart pointers.
652 Regular pointers are still used as union members and for pointers to arrays of
653 objects.
654 
655 @note The standard smart pointer `std::shared_ptr` is generally safe to use.
656 Other smart pointers such as `std::unique_ptr` and `std::auto_ptr` may cause
657 compile-time errors when classes have smart pointer members but no copy
658 constructor (a default copy constructor). A copy constructor is required for
659 non-shared smart pointer copying or swapping.
660 
661 Alternatives to `std::shared_ptr` of the form `NAMESPACE::shared_ptr` can be
662 assigned to `$POINTER` when the namespace `NAMESPACE` also implements
663 `NAMESPACE::make_shared` and when the shared pointer class provides `reset()`
664 and`get()` methods and the dereference operator. For example Boost
665 `boost::shared_ptr`:
666 
667  [
668  #include <boost/shared_ptr.hpp>
669  ]
670  $POINTER = boost::shared_ptr
671 
672 The user-defined content between `[` and `]` ensures that we include the Boost
673 header files that are needed to support `boost::shared_ptr` and
674 `boost::make_shared`.
675 
676 A Qt container can be used instead of the default `std::vector`, for example
677 `QVector`:
678 
679  [
680  #include <QVector>
681  ]
682  $CONTAINER = QVector
683 
684 User-defined content {#typemap6}
685 --------------------
686 
687 Any other content to be generated by wsdl2h can be included in `typemap.dat` by
688 enclosing it within brackets `[` and `]` anywhere in the `typemap.dat` file.
689 Each of the two brackets MUST appear at the start of a new line.
690 
691 For example, we can add an `#import "wsa5.h"` to the wsdl2h-generated output as
692 follows:
693 
694  [
695  #import "import/wsa5.h"
696  ]
697 
698 which emits the `#import "import/wsa5.h"` literally at the start of the
699 wsdl2h-generated header file.
700 
701 Mapping C/C++ to XML schema {#toxsd}
702 ===========================
703 
704 The soapcpp2 command generates the data binding implementation code from a data
705 binding interface `file.h`:
706 
707  soapcpp2 [options] file.h
708 
709 where `file.h` is a gSOAP header file that declares the XML data binding
710 interface. The `file.h` is typically generated by wsdl2h, but you can also
711 declare one yourself. If so, add `//gsaop` [directives](#directives) and
712 declare in this file all our C/C++ types you want to serialize in XML.
713 
714 You can also declare functions that will be converted to Web service operations
715 by soapcpp2. Global function declarations define service operations, which are
716 of the form:
717 
718 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
719  int prefix__func(arg1, arg2, ..., argn, result);
720 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
721 
722 where `arg1`, `arg2`, ..., `argn` are formal argument declarations of the input
723 and `result` is a formal argument for the output, which must be a pointer or
724 reference to the result object to be populated. More information can be found
725 in the [gSOAP user guide.](http://www.genivia.com/doc/soapdoc2.html)
726 
727 Overview of serializable C/C++ types {#toxsd1}
728 ------------------------------------
729 
730 The following C/C++ types are supported by soapcpp2 and mapped to XSD types
731 and constructs. See the subsections below for more details or follow the links.
732 
733 ### List of Boolean types
734 
735 | Boolean Type | Notes |
736 | ----------------------------- | ----------------------------------------------------------------------------------- |
737 | `bool` | C++ bool |
738 | `enum xsd__boolean` | C alternative to C++ `bool` with `false_` and `true_` |
739 
740 @see Section [C++ bool and C alternative](#toxsd3).
741 
742 ### List of enumeration and bitmask types
743 
744 | Enumeration Type | Notes |
745 | ----------------------------- | ----------------------------------------------------------------------------------- |
746 | `enum` | enumeration |
747 | `enum class` | C++11 scoped enumeration (soapcpp2 `-c++11`) |
748 | `enum*` | a bitmask that enumerates values 1, 2, 4, 8, ... |
749 | `enum* class` | C++11 scoped enumeration bitmask (soapcpp2 `-c++11`) |
750 
751 @see Section [enumerations and bitmasks](#toxsd4).
752 
753 ### List of numerical types
754 
755 | Numerical Type | Notes |
756 | ----------------------------- | ----------------------------------------------------------------------------------- |
757 | `char` | byte |
758 | `short` | 16 bit integer |
759 | `int` | 32 bit integer |
760 | `long` | 32 bit integer |
761 | `LONG64` | 64 bit integer |
762 | `xsd__integer` | 128 bit integer, use `#import "custom/int128.h"` |
763 | `long long` | same as `LONG64` |
764 | `unsigned char` | unsigned byte |
765 | `unsigned short` | unsigned 16 bit integer |
766 | `unsigned int` | unsigned 32 bit integer |
767 | `unsigned long` | unsigned 32 bit integer |
768 | `ULONG64` | unsigned 64 bit integer |
769 | `unsigned long long` | same as `ULONG64` |
770 | `int8_t` | same as `char` |
771 | `int16_t` | same as `short` |
772 | `int32_t` | same as `int` |
773 | `int64_t` | same as `LONG64` |
774 | `uint8_t` | same as `unsigned char` |
775 | `uint16_t` | same as `unsigned short` |
776 | `uint32_t` | same as `unsigned int` |
777 | `uint64_t` | same as `ULONG64` |
778 | `size_t` | transient type (not serializable) |
779 | `float` | 32 bit float |
780 | `double` | 64 bit float |
781 | `long double` | extended precision float, use `#import "custom/long_double.h"` |
782 | `xsd__decimal` | `<quadmath.h>` 128 bit quadruple precision float, use `#import "custom/float128.h"` |
783 | `typedef` | declares a type name, with optional value range and string length bounds |
784 
785 @see Section [numerical types](#toxsd5).
786 
787 ### List of string types
788 
789 | String Type | Notes |
790 | ----------------------------- | ----------------------------------------------------------------------------------- |
791 | `char*` | string (may contain UTF-8 with flag `SOAP_C_UTFSTRING`) |
792 | `wchar_t*` | wide string |
793 | `std::string` | C++ string (may contain UTF-8 with flag `SOAP_C_UTFSTRING`) |
794 | `std::wstring` | C++ wide string |
795 | `char[N]` | fixed-size string, requires soapcpp2 option `-b` |
796 | `_QName` | normalized QName content |
797 | `_XML` | literal XML string content with wide characters in UTF-8 |
798 | `typedef` | declares a new string type name, may restrict string length |
799 
800 @see Section [string types](#toxsd6).
801 
802 ### List of date and time types
803 
804 | Date and Time Type | Notes |
805 | --------------------------------------- | ------------------------------------------------------------------------- |
806 | `time_t` | date and time point since epoch |
807 | `struct tm` | date and time point, use `#import "custom/struct_tm.h"` |
808 | `struct tm` | date point, use `#import "custom/struct_tm_date.h"` |
809 | `struct timeval` | date and time point, use `#import "custom/struct_timeval.h"` |
810 | `unsigned long long` | time point in microseconds, use `#import "custom/long_time.h"` |
811 | `std::chrono::system_clock::time_point` | date and time point, use `#import "custom/chrono_time_point.h"` |
812 
813 @see Section [date and time types](#toxsd7).
814 
815 ### List of time duration types
816 
817 | Time Duration Type | Notes |
818 | ----------------------------- | ----------------------------------------------------------------------------------- |
819 | `long long` | duration in milliseconds, use `#import "custom/duration.h"` |
820 | `std::chrono::nanoseconds` | duration in nanoseconds, use `#import "custom/chrono_duration.h"` |
821 
822 @see Section [time duration types](#toxsd8).
823 
824 ### List of classes and structs
825 
826 | Classes, Structs, and Members | Notes |
827 | ----------------------------- | ----------------------------------------------------------------------------------- |
828 | `class` | C++ class with single inheritance only |
829 | `struct` | C struct or C++ struct without inheritance |
830 | `std::shared_ptr<T>` | C++11 smart shared pointer |
831 | `std::unique_ptr<T>` | C++11 smart pointer |
832 | `std::auto_ptr<T>` | C++ smart pointer |
833 | `std::deque<T>` | use `#import "import/stldeque.h"` |
834 | `std::list<T>` | use `#import "import/stllist.h"` |
835 | `std::vector<T>` | use `#import "import/stlvector.h"` |
836 | `std::set<T>` | use `#import "import/stlset.h"` |
837 | `template<T> class` | a container with `begin()`, `end()`, `size()`, `clear()`, and `insert()` methods |
838 | `T*` | data member: pointer to data of type `T` or points to array of `T` of size `__size` |
839 | `T[N]` | data member: fixed-size array of type `T` |
840 | `union` | data member: requires a variant selector member `__union` |
841 | `void*` | data member: requires a `__type` member to indicate the type of object pointed to |
842 
843 @see Section [classes and structs](#toxsd9).
844 
845 ### List of special classes and structs
846 
847 | Special Classes and Structs | Notes |
848 | ----------------------------- | ----------------------------------------------------------------------------------- |
849 | Special Array class/struct | single and multidimensional SOAP Arrays |
850 | Special Wrapper class/struct | complexTypes with simpleContent, wraps `__item` member |
851 | `xsd__hexBinary` | binary content |
852 | `xsd__base64Binary` | binary content and optional MIME/MTOM attachments |
853 | `xsd__anyType` | DOM elements, use `#import "dom.h"` |
854 | `@xsd__anyAttribute` | DOM attributes, use `#import "dom.h"` |
855 
856 @see Section [special classes and structs](#toxsd10).
857 
858 Colon notation versus name prefixing with XML tag name translation {#toxsd2}
859 ------------------------------------------------------------------
860 
861 To bind C/C++ type names to XSD types, a simple form of name prefixing is used
862 by the gSOAP tools by prepending the XML namespace prefix to the C/C++ type
863 name with a pair of undescrores. This also ensures that name clashes cannot
864 occur when multiple WSDL and XSD files are converted to C/C++. Also, C++
865 namespaces are not sufficiently rich to capture XML schema namespaces
866 accurately, for example when class members are associated with schema elements
867 defined in another XML namespace and thus the XML namespace scope of the
868 member's name is relevant, not just its type.
869 
870 However, from a C/C++ centric point of view this can be cumbersome. Therefore,
871 colon notation is an alternative to physically augmenting C/C++ names with
872 prefixes.
873 
874 For example, the following class uses colon notation to bind the `record` class
875 to the `urn:types` schema:
876 
877 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
878  //gsoap ns schema namespace: urn:types
879  class ns:record // binding 'ns:' to a type name
880  {
881  public:
882  std::string name;
883  uint64_t SSN;
884  ns:record *spouse; // using 'ns:' with the type name
885  ns:record(); // using 'ns:' here too
886  ~ns:record(); // and here
887  };
888 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
889 
890 The colon notation is stripped away by soapcpp2 when generating the data
891 binding implementation code for our project. So the final code just uses
892 `record` to identify this class and its constructor/destructor.
893 
894 When using colon notation make sure to be consistent and not use colon notation
895 mixed with prefixed forms. The name `ns:record` differs from `ns__record`,
896 because `ns:record` is compiled to an unqualified `record` name.
897 
898 Colon notation also facilitates overruling the elementFormDefault and
899 attributeFormDefault declaration that is applied to local elements and
900 attributes, when declared as members of classes, structs, and unions. For more
901 details, see [qualified and unqualified members](#toxsd9-6).
902 
903 A C/C++ identifier name (a type name, member name, function name, or parameter
904 name) is translated to an XML tag name by the following rules:
905 
906 - Two leading underscores indicates that the identifier name has no XML tag
907  name, i.e. this name is not visible in XML and is not translated.
908 - A leading underscore is removed, but the underscore indicates that: **a**) a
909  struct/class member name or parameter name has a wildcard XML tag name (i.e.
910  matches any XML tag), or **b**) a type name that has a
911  [document root element definition](#toxsd9-7).
912 - Trailing underscores are removed (i.e. trailing underscores can be used to
913  avoid name clashes with keywords).
914 - Underscores within names are translated to hyphens (hyphens are more common
915  in XML tags).
916 - `_USCORE` is translated to an underscore in the translated XML tag name.
917 - `_DOT` is translated to a dot (`.`) in the translated XML tag name.
918 - `_xHHHH` is translated to the Unicode character with code point HHHH (hex).
919 - C++11 Unicode identifier name characters in UTF-8 are translated as-is.
920 
921 For example, the C/C++ namespace qualified identifier name `s_a__my_way` is
922 translated to the XML tag name `s-a:my-way` by translating the prefix `s_a`
923 and the local name `my_way`.
924 
925 Struct/class member and parameter name translation can be overruled by using
926 [backtick XML tags](#toxsd9-5) (with gSOAP 2.8.30 and later versions).
927 
928 C++ Bool and C alternatives {#toxsd3}
929 ---------------------------
930 
931 The C++ `bool` type is bound to built-in XSD type `xsd:boolean`.
932 
933 The C alternative is to define an enumeration:
934 
935 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
936  enum xsd__boolean { false_, true_ };
937 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
938 
939 or by defining an enumeration in C with pseudo-scoped enumeration constants:
940 
941 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
942  enum xsd__boolean { xsd__boolean__false, xsd__boolean__true };
943 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
944 
945 The XML value space of these types is `false` and `true`, but also accepted
946 are `0` and `1` values for false and true, respectively.
947 
948 To prevent name clashes, `false_` and `true_` have an underscore. Trailing
949 underscores are removed from the XML value space.
950 
951 Enumerations and bitmasks {#toxsd4}
952 -------------------------
953 
954 Enumerations are mapped to XSD simpleType enumeration restrictions of
955 `xsd:string`, `xsd:QName`, and `xsd:long`.
956 
957 Consider for example:
958 
959 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
960  enum ns__Color { RED, WHITE, BLUE };
961 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
962 
963 which maps to a simpleType restriction of `xsd:string` in the soapcpp2-generated
964 schema:
965 
966  <simpleType name="Color">
967  <restriction base="xsd:string">
968  <enumeration value="RED"/>
969  <enumeration value="WHITE"/>
970  <enumeration value="BLUE"/>
971  </restriction>
972  </simpleType>
973 
974 Enumeration name constants can be pseudo-scoped to prevent name clashes,
975 because enumeration name constants have a global scope in C and C++:
976 
977 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
978  enum ns__Color { ns__Color__RED, ns__Color__WHITE, ns__Color__BLUE };
979 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
980 
981 You can also use C++11 scoped enumerations to prevent name clashes:
982 
983 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
984  enum class ns__Color : int { RED, WHITE, BLUE };
985 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
986 
987 Here, the enumeration class base type `: int` is optional. In place of `int`
988 in the example above, we can also use `int8_t`, `int16_t`, `int32_t`, or
989 `int64_t`.
990 
991 The XML value space of the enumertions defined above is `RED`, `WHITE`, and
992 `BLUE`.
993 
994 Prefix-qualified enumeration name constants are mapped to simpleType
995 restrictions of `xsd:QName`, for example:
996 
997 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
998  enum ns__types { xsd__int, xsd__float };
999 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1000 
1001 which maps to a simpleType restriction of `xsd:QName` in the soapcpp2-generated
1002 schema:
1003 
1004  <simpleType name="types">
1005  <restriction base="xsd:QName">
1006  <enumeration value="xsd:int"/>
1007  <enumeration value="xsd:float"/>
1008  </restriction>
1009  </simpleType>
1010 
1011 Enumeration name constants can be pseudo-numeric as follows:
1012 
1013 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1014  enum ns__Primes { _3 = 3, _5 = 5, _7 = 7, _11 = 11 };
1015 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1016 
1017 which maps to a simpleType restriction of `xsd:long`:
1018 
1019  <simpleType name="Color">
1020  <restriction base="xsd:long">
1021  <enumeration value="3"/>
1022  <enumeration value="5"/>
1023  <enumeration value="7"/>
1024  <enumeration value="11"/>
1025  </restriction>
1026  </simpleType>
1027 
1028 The XML value space of this type is `3`, `5`, `7`, and `11`.
1029 
1030 Besides (pseudo-) scoped enumerations, another way to prevent name clashes
1031 accross enumerations is to start an enumeration name constant with one
1032 underscore or followed it by any number of underscores, which makes it
1033 unique. The leading and trailing underscores are removed from the XML value
1034 space.
1035 
1036 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1037  enum ns__ABC { A, B, C };
1038  enum ns__BA { B, A }; // BAD: B = 1 but B is already defined as 2
1039  enum ns__BA_ { B_, A_ }; // OK
1040 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1041 
1042 The gSOAP soapcpp2 tool permits reusing enumeration name constants across
1043 (non-scoped) enumerations as long as these values are assigned the same
1044 constant. Therefore, the following is permitted:
1045 
1046 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1047  enum ns__Primes { _3 = 3, _5 = 5, _7 = 7, _11 = 11 };
1048  enum ns__Throws { _1 = 1, _2 = 2, _3 = 3, _4 = 4, _5 = 5, _6 = 6 };
1049 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1050 
1051 A bitmask type is an `enum*` "product" enumeration with a geometric,
1052 power-of-two sequence of values assigned to the enumeration constants:
1053 
1054 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1055  enum* ns__Options { SSL3, TLS10, TLS11, TLS12 };
1056 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1057 
1058 where the product enum assigns 1 to `SSL3`, 2 to `TLS10`, 4 to `TLS11`, and 8
1059 to `TLS12`, which allows these enumeration constants to be used in composing
1060 bitmasks with `|` (bitwise or) `&` (bitwise and), and `~` (bitwise not):
1061 
1062 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1063  enum ns__Options options = (enum ns__Options)(SSL3 | TLS10 | TLS11 | TLS12);
1064  if (options & SSL3) // if SSL3 is an option, warn and remove from options
1065  {
1066  warning();
1067  options &= ~SSL3;
1068  }
1069 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1070 
1071 The bitmask type maps to a simpleType list restriction of `xsd:string` in the
1072 soapcpp2-generated schema:
1073 
1074  <simpleType name="Options">
1075  <list>
1076  <restriction base="xsd:string">
1077  <enumeration value="SSL3"/>
1078  <enumeration value="TLS10"/>
1079  <enumeration value="TLS11"/>
1080  <enumeration value="TLS12"/>
1081  </restriction>
1082  </list>
1083  </simpleType>
1084 
1085 The XML value space of this type consists of all 16 possible subsets of the
1086 four values, represented by an XML string with space-separated values. For
1087 example, the bitmask `TLS10 | TLS11 | TLS12` equals 14 and is represented by
1088 the XML string `TLS10 TLS11 TLS12`.
1089 
1090 You can also use C++11 scoped enumerations with bitmasks:
1091 
1092 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1093  enum* class ns__Options { SSL3, TLS10, TLS11, TLS12 };
1094 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1095 
1096 The base type of a scoped enumeration bitmask, when explicitly given, is
1097 ignored. The base type is either `int` or `int64_t`, depending on the number
1098 of constants enumerated in the bitmask.
1099 
1100 To convert `enum` name constants and bitmasks to a string, we use the
1101 auto-generated function for enum `T`:
1102 
1103 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1104  const char *soap_T2s(struct soap*, enum T val)
1105 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1106 
1107 The string returned is stored in an internal buffer of the current `soap`
1108 context, so you MUST copy it to keep it from being overwritten. For example,
1109 use `char *soap_strdup(struct soap*, const char*)`.
1110 
1111 To convert a string to an `enum` constant or bitmask, we use the auto-generated
1112 function
1113 
1114 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1115  int soap_s2T(struct soap*, const char *str, enum T *val)
1116 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1117 
1118 This function takes the name (or names, space-separated for bitmasks) of
1119 the enumeration constant in a string `str`. Names should be given without the
1120 pseudo-scope prefix and without trailing underscores. The function sets `val`
1121 to the corresponding integer enum constant or to a bitmask. The function
1122 returns `SOAP_OK` (zero) on success or an error if the string is not a valid
1123 enumeration name.
1124 
1125 Numerical types {#toxsd5}
1126 ---------------
1127 
1128 Integer and floating point types are mapped to the equivalent built-in XSD
1129 types with the same sign and bit width.
1130 
1131 The `size_t` type is transient (not serializable) because its width is platform
1132 dependent. We recommend to use `uint64_t` instead.
1133 
1134 The XML value space of integer types are their decimal representations without
1135 loss of precision.
1136 
1137 The XML value space of floating point types are their decimal representations.
1138 The decimal representations are formatted with the printf format string "%.9G"
1139 for floats and the printf format string "%.17lG" for double. To change the
1140 format strings, we can assign new strings to the following `struct soap`
1141 context members:
1142 
1143 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1144  soap.float_format = "%g";
1145  soap.double_format = "%lg";
1146  soap.long_double_format = "%Lg";
1147 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1148 
1149 Note that decimal representations may result in a loss of precision of the
1150 least significant decimal. Therefore, the format strings that are used by
1151 default are sufficiently precise to avoid loss, but this may result in long
1152 decimal fractions in the XML value space.
1153 
1154 The `long double` extended floating point type requires a custom serializer:
1155 
1156 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1157  #import "custom/long_double.h"
1158  ... use long double ...
1159 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1160 
1161 You can now use `long double`, which has a serializer that serializes this type
1162 as `xsd:decimal`. Compile and link your code with `custom/long_double.c`.
1163 
1164 The value space of floating point values includes the special values `INF`,
1165 `-INF`, and `NaN`. You can check a value for plus or minus infinity and
1166 not-a-number as follows:
1167 
1168 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1169  soap_isinf(x) && x > 0 // is x INF?
1170  soap_isinf(x) && x < 0 // is x -INF?
1171  soap_isnan(x) // is x NaN?
1172 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1173 
1174 To assign these values, use:
1175 
1176 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1177  // x is float // x is double, long double, or __float128
1178  x = FLT_PINFY; x = DBL_PINFTY;
1179  x = FLT_NINFY; x = DBL_NINFTY;
1180  x = FLT_NAN; x = DBL_NAN;
1181 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1182 
1183 If your system supports `__float128` then you can also use this 128 bit
1184 floating point type with a custom serializer:
1185 
1186 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1187  #import "custom/float128.h"
1188  ... use xsd__decimal ...
1189 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1190 
1191 Then use the `xsd__decimal` alias of `__float128`, which has a serializer. Do
1192 not use `__float128` directly, which is transient (not serializable).
1193 
1194 To check for `INF`, `-INF`, and `NaN` of a `__float128` value use:
1195 
1196 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1197  isinfq(x) && x > 0 // is x INF?
1198  isinfq(x) && x < 0 // is x -INF?
1199  isnanq(x) // is x NaN?
1200 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1201 
1202 The range of a typedef-defined numerical type can be restricted using the range
1203 `:` operator with inclusive lower and upper bounds. For example:
1204 
1205 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1206  typedef int ns__narrow -10 : 10;
1207 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1208 
1209 This maps to a simpleType restriction of `xsd:int` in the soapcpp2-generated
1210 schema:
1211 
1212  <simpleType name="narrow">
1213  <restriction base="xsd:int">
1214  <minInclusive value="-10"/>
1215  <maxInclusive value="10"/>
1216  </restriction>
1217  </simpleType>
1218 
1219 The lower and upper bound of a range are optional. When omitted, values are
1220 not bound from below or from above, respectively.
1221 
1222 The range of a floating point typedef-defined type can be restricted within
1223 floating point constant bounds.
1224 
1225 Also with a floating point typedef a printf format pattern can be given of the
1226 form `"%[width][.precision]f"` to format decimal values using the given width
1227 and precision fields:
1228 
1229 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1230  typedef float ns__PH "%5.2f" 0.0 : 14.0;
1231 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1232 
1233 This maps to a simpleType restriction of `xsd:float` in the soapcpp2-generated
1234 schema:
1235 
1236  <simpleType name="PH">
1237  <restriction base="xsd:float">
1238  <totalDigits value="5"/>
1239  <fractionDigits value="2"/>
1240  <minInclusive value="0"/>
1241  <maxInclusive value="14"/>
1242  </restriction>
1243  </simpleType>
1244 
1245 For exclusive bounds, we use the `<` operator instead of the `:` range
1246 operator:
1247 
1248 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1249  typedef float ns__epsilon 0.0 < 1.0;
1250 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1251 
1252 Values `eps` of `ns__epsilon` are restricted between `0.0 < eps < 1.0`.
1253 
1254 This maps to a simpleType restriction of `xsd:float` in the soapcpp2-generated
1255 schema:
1256 
1257  <simpleType name="epsilon">
1258  <restriction base="xsd:float">
1259  <minExclusive value="0"/>
1260  <maxExclusive value="1"/>
1261  </restriction>
1262  </simpleType>
1263 
1264 To make just one of the bounds exclusive, while keeping the other bound
1265 inclusive, we add a `<` on the left or on the right side of the range ':'
1266 operator. For example:
1267 
1268 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1269  typedef float ns__pos 0.0 < : ; // 0.0 < pos
1270  typedef float ns__neg : < 0.0 ; // neg < 0.0
1271 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1272 
1273 It is valid to make both left and right side exclusive with `< : <` which is in
1274 fact identical to the exlusive range `<` operator:
1275 
1276 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1277  typedef float ns__epsilon 0.0 < : < 1.0; // 0.0 < eps < 1.0
1278 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1279 
1280 It helps to think of the `:` as a placeholder of the value between the two
1281 bounds, which is easier to memorize than the shorthand forms of bounds from
1282 which the `:` is removed:
1283 
1284 | Bounds | Validation Check | Shorthand |
1285 | ---------- | ---------------- | --------- |
1286 | 1 : | 1 <= x | 1 |
1287 | 1 : 10 | 1 <= x <= 10 | |
1288 | : 10 | x <= 10 | |
1289 | 1 < : < 10 | 1 < x < 10 | 1 < 10 |
1290 | 1 : < 10 | 1 <= x < 10 | |
1291 | : < 10 | x < 10 | < 10 |
1292 | 1 < : | 1 < x | 1 < |
1293 | 1 < : 10 | 1 < x <= 10 | |
1294 
1295 Besides `float`, also `double` and `long double` values can be restricted. For
1296 example, consider a nonzero probability extended floating point precision type:
1297 
1298 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1299  #import "custom/long_double.h"
1300  typedef long double ns__probability "%16Lg" 0.0 < : 1.0;
1301 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1302 
1303 Value range restrictions are validated by the parser for all inbound XML data.
1304 A type fault `SOAP_TYPE` will be thrown by the deserializer if the value is out
1305 of range.
1306 
1307 Finally, if your system supports `__int128_t` then you can also use this 128
1308 bit integer type with a custom serializer:
1309 
1310 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1311  #import "custom/int128.h"
1312  ... use xsd__integer ...
1313 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1314 
1315 Use the `xsd__integer` alias of `__int128_t`, which has a serializer. Do not
1316 use `__int128_t` directly, which is transient (not serializable).
1317 
1318 To convert numeric values to a string, we use the auto-generated function for
1319 numeric type `T`:
1320 
1321 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1322  const char *soap_T2s(struct soap*, T val)
1323 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1324 
1325 For numeric types `T`, the string returned is stored in an internal buffer of
1326 the current `soap` context, so you MUST copy it to keep it from being
1327 overwritten. For example, use `char *soap_strdup(struct soap*, const char*)`.
1328 
1329 To convert a string to a numeric value, we use the auto-generated function
1330 
1331 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1332  int soap_s2T(struct soap*, const char *str, T *val)
1333 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1334 
1335 where `T` is for example `int`, `LONG64`, `float`, `decimal` (the custom
1336 serializer name of `long double`) or `xsd__integer` (the custom serializer name
1337 of `__int128_t`). The function `soap_s2T` returns `SOAP_OK` on success or an
1338 error when the value is not numeric. For floating point types, "INF", "-INF"
1339 and "NaN" are valid strings to convert to numbers.
1340 
1341 String types {#toxsd6}
1342 ------------
1343 
1344 String types are mapped to the built-in `xsd:string` and `xsd:QName` XSD types.
1345 
1346 The wide strings `wchar_t*` and `std::wstring` may contain Unicode that is
1347 preserved in the XML value space.
1348 
1349 Strings `char*` and `std::string` can only contain extended Latin, but we can
1350 store UTF-8 content that is preserved in the XML value space when the `struct
1351 soap` context is initialized with the flag `SOAP_C_UTFSTRING`.
1352 
1353 @warning Beware that many XML 1.0 parsers reject all control characters (those
1354 between `#x1` and `#x1F`) except for `#x9`, `#xA`, and `#xD`. With the
1355 newer XML 1.1 version parsers (including gSOAP) you should be fine.
1356 
1357 The length of a string of a typedef-defined string type can be restricted:
1358 
1359 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1360  typedef std::string ns__password 6 : 16;
1361 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1362 
1363 which maps to a simpleType restriction of `xsd:string` in the soapcpp2-generated
1364 schema:
1365 
1366  <simpleType name="password">
1367  <restriction base="xsd:string">
1368  <minLength value="6"/>
1369  <maxLength value="16"/>
1370  </restriction>
1371  </simpleType>
1372 
1373 String length restrictions are validated by the parser for inbound XML data.
1374 A value length fault `SOAP_LENGTH` will be thrown by the deserializer if the
1375 string is too long or too short.
1376 
1377 In addition, an XSD regex pattern restriction can be associated with a string
1378 typedef:
1379 
1380 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1381  typedef std::string ns__password "([a-zA-Z]|[0-9]|-)+" 6 : 16;
1382 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1383 
1384 which maps to a simpleType restriction of `xsd:string` in the soapcpp2-generated
1385 schema:
1386 
1387  <simpleType name="password">
1388  <restriction base="xsd:string">
1389  <pattern value="([a-zA-Z0-9]|-)+"/>
1390  <minLength value="6"/>
1391  <maxLength value="16"/>
1392  </restriction>
1393  </simpleType>
1394 
1395 Pattern restrictions are validated by the parser for inbound XML data only if
1396 the `soap::fsvalidate` and `soap::fwvalidate` callbacks are defined, see the
1397 [gSOAP user guide.](http://www.genivia.com/doc/soapdoc2.html)
1398 
1399 Exclusive length bounds can be used with strings:
1400 
1401 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1402  typedef std::string ns__string255 : < 256; // same as 0 : 255
1403 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1404 
1405 Fixed-size strings (`char[N]`) are rare occurrences in the wild, but apparently
1406 still used in some projects to store strings. To facilitate fixed-size string
1407 serialization, use soapcpp2 option `-b`. For example:
1408 
1409 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1410  typedef char ns__buffer[10]; // requires soapcpp2 option -b
1411 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1412 
1413 which maps to a simpleType restriction of `xsd:string` in the soapcpp2-generated
1414 schema:
1415 
1416  <simpleType name="buffer">
1417  <restriction base="xsd:string">
1418  <maxLength value="9"/>
1419  </restriction>
1420  </simpleType>
1421 
1422 Note that fixed-size strings MUST contain NUL-terminated text and SHOULD NOT
1423 contain raw binary data. Also, the length limitation is more restrictive for
1424 UTF-8 content (enabled with the `SOAP_C_UTFSTRING`) that requires multibyte
1425 character encodings. As a consequence, UTF-8 content may be truncated to fit.
1426 
1427 Note that raw binary data can be stored in a `xsd__base64Binary` or
1428 `xsd__hexBinary` structure, or transmitted as a MIME attachment.
1429 
1430 The built-in `_QName` type is a regular C string type (`char*`) that maps to
1431 `xsd:QName` but has the added advantage that it holds normalized qualified names.
1432 There are actually two forms of normalized QName content, to ensure any QName
1433 is represented accurately and uniquely:
1434 
1435 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1436  "prefix:name"
1437  "\"URI\":name"
1438 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1439 
1440 The first form of string is used when the prefix (and the binding URI) is
1441 defined in the namespace table and is bound to a URI (see the .nsmap file).
1442 The second form is used when the URI is not defined in the namespace table and
1443 therefore no prefix is available to bind and normalize the URI to.
1444 
1445 A `_QName` string may contain a sequence of space-separated QName values, not
1446 just one, and all QName values are normalized to the format shown above.
1447 
1448 To define a `std::string` base type for `xsd:QName`, we use a typedef:
1449 
1450 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1451  typedef std::string xsd__QName;
1452 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1453 
1454 The `xsd__QName` string content is normalized, just as with the `_QName`
1455 normalization.
1456 
1457 To serialize strings that contain literal XML content to be reproduced in the
1458 XML value space, use the built-in `_XML` string type, which is a regular C
1459 string type (`char*`) that maps to plain XML CDATA.
1460 
1461 To define a `std::string` base type for literal XML content, use a typedef:
1462 
1463 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1464  typedef std::string XML;
1465 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1466 
1467 Strings can hold any of the values of the XSD built-in primitive types. We can
1468 use a string typedef to declare the use of the string type as a XSD built-in
1469 type:
1470 
1471 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1472  typedef std::string xsd__token;
1473 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1474 
1475 You MUST ensure that the string values we populate in this type conform to the
1476 XML standard, which in case of `xsd:token` is the lexical and value spaces of
1477 `xsd:token` are the sets of all strings after whitespace replacement of any
1478 occurrence of `#x9`, `#xA` , and `#xD` by `#x20` and collapsing.
1479 
1480 To copy `char*` or `wchar_t*` strings with a context that manages the allocated
1481 memory, use functions
1482 
1483 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1484  char *soap_strdup(struct soap*, const char*)
1485  wchar_t *soap_wstrdup(struct soap*, const wchar_t*)
1486 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1487 
1488 To convert a wide string to a UTF-8 encoded string, use function
1489 
1490 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1491  const char* SOAP_FMAC2 soap_wchar2s(struct soap*, const wchar_t *s)
1492 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1493 
1494 The function allocates and returns a string, with its memory being managed by
1495 the context.
1496 
1497 To convert a UTF-8 encoded string to a wide string, use function
1498 
1499 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1500  int soap_s2wchar(struct soap*, const char *from, wchar_t **to, long minlen, long maxlen)
1501 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1502 
1503 where `to` is set to point to an allocated `wchar_t*` string. Pass `-1` for
1504 `minlen` and `maxlen` to ignore length constraints on the target string. The
1505 function returns `SOAP_OK` or an error when the length constraints are not met.
1506 
1507 Date and time types {#toxsd7}
1508 -------------------
1509 
1510 The C/C++ `time_t` type is mapped to the built-in `xsd:dateTime` XSD type that
1511 represents a date and time within a time zone (typically UTC).
1512 
1513 The XML value space contains ISO 8601 Gregorian time instances of the form
1514 `[-]CCYY-MM-DDThh:mm:ss.sss[Z|(+|-)hh:mm]`, where `Z` is the UTC time zone
1515 or a time zone offset `(+|-)hh:mm]` from UTC is used.
1516 
1517 A `time_t` value is considered and represented in UTC by the serializer.
1518 
1519 Because the `time_t` value range is restricted to dates after 01/01/1970 and
1520 before 2038 assuming `time_t` is a `long` 32 bit, care must be taken to ensure
1521 the range of `xsd:dateTime` values in XML exchanges do not exceed the `time_t`
1522 range.
1523 
1524 This restriction does not hold for `struct tm` (`<time.h>`), which we can use
1525 to store and exchange a date and time in UTC without date range restrictions.
1526 The serializer uses the `struct tm` members directly for the XML value space of
1527 `xsd:dateTime`:
1528 
1529 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1530  struct tm
1531  {
1532  int tm_sec; // seconds (0 - 60)
1533  int tm_min; // minutes (0 - 59)
1534  int tm_hour; // hours (0 - 23)
1535  int tm_mday; // day of month (1 - 31)
1536  int tm_mon; // month of year (0 - 11)
1537  int tm_year; // year - 1900
1538  int tm_wday; // day of week (Sunday = 0) (NOT USED)
1539  int tm_yday; // day of year (0 - 365) (NOT USED)
1540  int tm_isdst; // is summer time in effect?
1541  char* tm_zone; // abbreviation of timezone (NOT USED)
1542  };
1543 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1544 
1545 You will lose the day of the week information. It is always Sunday
1546 (`tm_wday=0`) and the day of the year is not set either. The time zone is UTC.
1547 
1548 This `struct tm` type is mapped to the built-in `xsd:dateTime` XSD type and
1549 serialized with the custom serializer `custom/struct_tm.h` that declares a
1550 `xsd__dateTime` type:
1551 
1552 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1553  #import "custom/struct_tm.h" // import typedef struct tm xsd__dateTime;
1554  ... use xsd__dateTime ...
1555 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1556 
1557 Compile and link your code with `custom/struct_tm.c`.
1558 
1559 The `struct timeval` (`<sys/time.h>`) type is mapped to the built-in
1560 `xsd:dateTime` XSD type and serialized with the custom serializer
1561 `custom/struct_timeval.h` that declares a `xsd__dateTime` type:
1562 
1563 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1564  #import "custom/struct_timeval.h" // import typedef struct timeval xsd__dateTime;
1565  ... use xsd__dateTime ...
1566 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1567 
1568 Compile and link your code with `custom/struct_timeval.c`.
1569 
1570 Note that the same value range restrictions apply to `struct timeval` as they
1571 apply to `time_t`. The added benefit of `struct timeval` is the addition of
1572 a microsecond-precise clock:
1573 
1574 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1575  struct timeval
1576  {
1577  time_t tv_sec; // seconds since Jan. 1, 1970
1578  suseconds_t tv_usec; // and microseconds
1579  };
1580 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1581 
1582 A C++11 `std::chrono::system_clock::time_point` type is mapped to the built-in
1583 `xsd:dateTime` XSD type and serialized with the custom serializer
1584 `custom/chrono_time_point.h` that declares a `xsd__dateTime` type:
1585 
1586 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1587  #import "custom/chrono_time_point.h" // import typedef std::chrono::system_clock::time_point xsd__dateTime;
1588  ... use xsd__dateTime ...
1589 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1590 
1591 Compile and link your code with `custom/chrono_time_point.cpp`.
1592 
1593 The `struct tm` type is mapped to the built-in `xsd:date` XSD type and serialized
1594 with the custom serializer `custom/struct_tm_date.h` that declares a
1595 `xsd__date` type:
1596 
1597 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1598  #import "custom/struct_tm_date.h" // import typedef struct tm xsd__date;
1599  ... use xsd__date ...
1600 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1601 
1602 Compile and link your code with `custom/struct_tm_date.c`.
1603 
1604 The XML value space of `xsd:date` are Gregorian calendar dates of the form
1605 `[-]CCYY-MM-DD[Z|(+|-)hh:mm]` with a time zone.
1606 
1607 The serializer ignores the time part and the deserializer only populates the
1608 date part of the struct, setting the time to 00:00:00. There is no unreasonable
1609 limit on the date range because the year field is stored as an integer (`int`).
1610 
1611 An `unsigned long long` (`ULONG64` or `uint64_t`) type that contains a 24 hour
1612 time in microseconds UTC is mapped to the built-in `xsd:time` XSD type and
1613 serialized with the custom serializer `custom/long_time.h` that declares a
1614 `xsd__time` type:
1615 
1616 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1617  #import "custom/long_time.h" // import typedef unsigned long long xsd__time;
1618  ... use xsd__time ...
1619 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1620 
1621 Compile and link your code with `custom/long_time.c`.
1622 
1623 This type represents `00:00:00.000000` to `23:59:59.999999`, from 0 to an
1624 upper bound of 86,399,999,999. A microsecond resolution means that a 1 second
1625 increment requires an increment of 1,000,000 in the integer value.
1626 
1627 The XML value space of `xsd:time` are points in time recurring each day of the
1628 form `hh:mm:ss.sss[Z|(+|-)hh:mm]`, where `Z` is the UTC time zone or a time
1629 zone offset from UTC is used. The `xsd__time` value is always considered and
1630 represented in UTC by the serializer.
1631 
1632 To convert date and/or time values to a string, we use the auto-generated
1633 function for type `T`:
1634 
1635 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1636  const char *soap_T2s(struct soap*, T val)
1637 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1638 
1639 For date and time types `T`, the string returned is stored in an internal
1640 buffer of the current `soap` context, so you MUST copy it to keep it from being
1641 overwritten. For example, use `char *soap_strdup(struct soap*, const char*)`.
1642 
1643 To convert a string to a date/time value, we use the auto-generated function
1644 
1645 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1646  int soap_s2T(struct soap*, const char *str, T *val)
1647 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1648 
1649 where `T` is for example `dateTime` (for `time_t`), `xsd__dateTime` (for
1650 `struct tm`, `struct timeval`, or `std::chrono::system_clock::time_point`).
1651 The function `soap_s2T` returns `SOAP_OK` on success or an error when the value
1652 is not a date/time.
1653 
1654 Time duration types {#toxsd8}
1655 -------------------
1656 
1657 The XML value space of `xsd:duration` are values of the form `PnYnMnDTnHnMnS`
1658 where the capital letters are delimiters. Delimiters may be omitted when the
1659 corresponding member is not used.
1660 
1661 A `long long` (`LONG64` or `int64_t`) type that contains a duration (time
1662 lapse) in milliseconds is mapped to the built-in `xsd:duration` XSD type and
1663 serialized with the custom serializer `custom/duration.h` that declares a
1664 `xsd__duration` type:
1665 
1666 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1667  #import "custom/duration.h" // import typedef long long xsd__duration;
1668  ... use xsd__duration ...
1669 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1670 
1671 Compile and link your code with `custom/duration.c`.
1672 
1673 The duration type `xsd__duration` can represent 106,751,991,167 days forward
1674 and backward with millisecond precision.
1675 
1676 Durations that exceed a month are always output in days, rather than months to
1677 avoid days-per-month conversion inacurracies.
1678 
1679 Durations that are received in years and months instead of total number of days
1680 from a reference point are not well defined, since there is no accepted
1681 reference time point (it may or may not be the current time). The decoder
1682 simple assumes that there are 30 days per month. For example, conversion of
1683 "P4M" gives 120 days. Therefore, the durations "P4M" and "P120D" are assumed
1684 to be identical, which is not necessarily true depending on the reference point
1685 in time.
1686 
1687 Rescaling of the duration value by may be needed when adding the duration value
1688 to a `time_t` value, because `time_t` may or may not have a seconds resolution,
1689 depending on the platform and possible changes to `time_t`.
1690 
1691 Rescaling is done automatically when you add a C++11 `std::chrono::nanoseconds`
1692 value to a `std::chrono::system_clock::time_point` value. To use
1693 `std::chrono::nanoseconds` as `xsd:duration`:
1694 
1695 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1696  #import "custom/chrono_duration.h" // import typedef std::chrono::duration xsd__duration;
1697  ... use xsd__duration ...
1698 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1699 
1700 Compile and link your code with `custom/chrono_duration.cpp`.
1701 
1702 This type can represent 384,307,168 days (2^63 nanoseconds) forwards and
1703 backwards in time in increments of 1 ns (1/1000000000 second).
1704 
1705 The same observations with respect to receiving durations in years and months
1706 apply to this serializer's decoder.
1707 
1708 To convert duration values to a string, we use the auto-generated function
1709 
1710 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1711  const char *soap_xsd__duration2s(struct soap*, xsd__duration val)
1712 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1713 
1714 The string returned is stored in an internal buffer, so you MUST copy it to
1715 keep it from being overwritten, Use `soap_strdup(struct soap*, const char*)`
1716 for example to copy this string.
1717 
1718 To convert a string to a duration value, we use the auto-generated function
1719 
1720 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1721  int soap_s2xsd__dateTime(struct soap*, const char *str, xsd__dateTime *val)
1722 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1723 
1724 The function returns `SOAP_OK` on success or an error when the value is not a
1725 duration.
1726 
1727 Classes and structs {#toxsd9}
1728 -------------------
1729 
1730 Classes and structs are mapped to XSD complexTypes. The XML value space
1731 consists of XML elements with attributes and subelements, possibly constrained
1732 by validation rules that enforce element and attribute occurrence contraints,
1733 numerical value range constraints, and string length and pattern constraints.
1734 
1735 Classes that are declared with the gSOAP tools are limited to single
1736 inheritence only. Structs cannot be inherited.
1737 
1738 The class and struct name is bound to an XML namespace by means of the prefix
1739 naming convention or by using [colon notation](#toxsd1):
1740 
1741 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1742  //gsoap ns schema namespace: urn:types
1743  class ns__record
1744  {
1745  public:
1746  std::string name;
1747  uint64_t SSN;
1748  ns__record *spouse;
1749  ns__record();
1750  ~ns__record();
1751  protected:
1752  struct soap *soap;
1753  };
1754 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1755 
1756 In the example above, we also added a context pointer to the `struct soap` that
1757 manages this instance. It is set when the instance is created in the engine's
1758 context, for example when deserialized and populated by the engine.
1759 
1760 The class maps to a complexType in the soapcpp2-generated schema:
1761 
1762  <complexType name="record">
1763  <sequence>
1764  <element name="name" type="xsd:string" minOccurs="1" maxOccurs="1"/>
1765  <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1"/>
1766  <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/>
1767  </sequence>
1768  </complexType>
1769 
1770 ### Serializable versus transient types and data members {#toxsd9-1}
1771 
1772 Public data members of a class or struct are serialized. Private and protected
1773 members are transient and not serializable.
1774 
1775 Also `const` and `static` members are not serializable, with the exception of
1776 `const char*` and `const wchar_t*`. Types and specific class/struct members
1777 can also be made transient with the `extern` qualifier:
1778 
1779 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1780  extern class std::ostream; // declare 'std::ostream' transient
1781  class ns__record
1782  {
1783  public:
1784  extern int num; // not serialized
1785  std::ostream out; // not serialized
1786  static const int MAX = 1024; // not serialized
1787  };
1788 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1789 
1790 By declaring `std::ostream` transient with `extern` you can use this type
1791 wherever you need it without soapcpp2 complaining that this class is not
1792 defined.
1793 
1794 ### Volatile classes and structs {#toxsd9-2}
1795 
1796 Classes and structs can be declared `volatile` with the gSOAP tools. This means
1797 that they are already declared elsewhere in your project's source code and you
1798 do not want soapcpp2 to generate code with a second declaration of these types.
1799 
1800 For example, `struct tm` is declared in `<time.h>`. You can make it serializable
1801 and include a partial list of data members that you want to serialize:
1802 
1803 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1804  volatile struct tm
1805  {
1806  int tm_sec; // seconds (0 - 60)
1807  int tm_min; // minutes (0 - 59)
1808  int tm_hour; // hours (0 - 23)
1809  int tm_mday; // day of month (1 - 31)
1810  int tm_mon; // month of year (0 - 11)
1811  int tm_year; // year - 1900
1812  };
1813 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1814 
1815 You can declare classes and structs `volatile` for any such types you want to
1816 serialize by only providing the public data members you want to serialize.
1817 
1818 In addition, [colon notation](#toxsd2) is a simple and effective way to bind an
1819 existing class or struct to a schema. For example, you can change the `tm` name
1820 as follows without affecting the code that uses `struct tm` generated by
1821 soapcpp2:
1822 
1823 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1824  volatile struct ns:tm { ... }
1825 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1826 
1827 This struct maps to a complexType in the soapcpp2-generated schema:
1828 
1829  <complexType name="tm">
1830  <sequence>
1831  <element name="tm-sec" type="xsd:int" minOccurs="1" maxOccurs="1"/>
1832  <element name="tm-min" type="xsd:int" minOccurs="1" maxOccurs="1"/>
1833  <element name="tm-hour" type="xsd:int" minOccurs="1" maxOccurs="1"/>
1834  <element name="tm-mday" type="xsd:int" minOccurs="1" maxOccurs="1"/>
1835  <element name="tm-mon" type="xsd:int" minOccurs="1" maxOccurs="1"/>
1836  <element name="tm-year" type="xsd:int" minOccurs="1" maxOccurs="1"/>
1837  </sequence>
1838  </complexType>
1839 
1840 ### Mutable classes and structs {#toxsd9-3}
1841 
1842 Classes and structs can be declared `mutable` with the gSOAP tools. This means
1843 that their definition can be spread out over the source code. This promotes the
1844 concept of a class or struct as a *row of named values*, also known as a *named
1845 tuple*, that can be extended at compile time in your source code with additional
1846 members. Because these types differ from the traditional object-oriented
1847 principles and design concepts of classes and objects, constructors and
1848 destructors cannot be defined (also because we cannot guarantee merging these
1849 into one such that all members will be initialized). A default constructor,
1850 copy constructor, assignment operation, and destructor will be assigned
1851 automatically by soapcpp2.
1852 
1853 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1854  mutable struct ns__tuple
1855  {
1856  @std::string id;
1857  };
1858 
1859  mutable struct ns__tuple
1860  {
1861  std::string name;
1862  std::string value;
1863  };
1864 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1865 
1866 The members are collected into one definition generated by soapcpp2. Members
1867 may be repeated from one definition to another, but only if their associated
1868 types are identical. So, for example, a third extension with a `value` member
1869 with a different type fails:
1870 
1871 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1872  mutable struct ns__tuple
1873  {
1874  float value; // BAD: value is already declared std::string
1875  };
1876 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1877 
1878 The `mutable` concept has proven to be very useful when declaring and
1879 collecting SOAP Headers for multiple services, which are collected into one
1880 `struct SOAP_ENV__Header` by the soapcpp2 tool.
1881 
1882 ### Default member values in C and C++ {#toxsd9-4}
1883 
1884 Class and struct data members in C and C++ may be declared with an optional
1885 default initialization value that is provided "inline" with the declaration of
1886 the member:
1887 
1888 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1889  class ns__record
1890  {
1891  public:
1892  std::string name = "Joe";
1893  ...
1894  };
1895 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1896 
1897 Alternatively, use C++11 default initialization syntax:
1898 
1899 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1900  class ns__record
1901  {
1902  public:
1903  std::string name { "Joe" };
1904  ...
1905  };
1906 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1907 
1908 These initializations are made by the default constructor that is added by
1909 soapcpp2 to each class and struct (in C++ only). A constructor is only added
1910 when a default constructor is not already defined with the class declaration.
1911 
1912 You can explicitly (re)initialize an object with these initial values by using
1913 the soapcpp2 auto-generated functions:
1914 
1915 - `void T::soap_default(struct soap*)` for `class T` (C++ only)
1916 - `void soap_default_T(struct soap*, T*)` for `struct T` (C and C++).
1917 
1918 Initializations can only be provided for members that have primitive types
1919 (`bool`, `enum`, `time_t`, numeric and string types).
1920 
1921 @see Section [operations on classes and structs](#toxsd9-13).
1922 
1923 ### Attribute members and backtick XML tags {#toxsd9-5}
1924 
1925 Class and struct data members are declared as XML attributes by annotating
1926 their type with a `@` qualifier:
1927 
1928 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1929  class ns__record
1930  {
1931  public:
1932  @std::string name;
1933  @uint64_t SSN;
1934  ns__record *spouse;
1935  };
1936 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1937 
1938 This class maps to a complexType in the soapcpp2-generated schema:
1939 
1940  <complexType name="record">
1941  <sequence>
1942  <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/>
1943  </sequence>
1944  <attribute name="name" type="xsd:string" use="required"/>
1945  <attribute name="SSN" type="xsd:unsignedLong" use="required"/>
1946  </complexType>
1947 
1948 An example XML instance of `ns__record` is:
1949 
1950  <ns:record xmlns:ns="urn:types" name="Joe" SSN="1234567890">
1951  <spouse name="Jane" SSN="1987654320">
1952  </spouse>
1953  </ns:record>
1954 
1955 Attribute data members are restricted to primitive types (`bool`, `enum`,
1956 `time_t`, numeric and string types), `xsd__hexBinary`, `xsd__base64Binary`, and
1957 custom serializers, such as `xsd__dateTime`. Custom serializers for types that
1958 may be used as attributes MUST define `soap_s2T` and `soap_T2s` functions that
1959 convert values of type `T` to strings and back.
1960 
1961 Attribute data members can be pointers and smart pointers to these types, which
1962 permits attributes to be optional.
1963 
1964 The XML tag name of a class/struct member is the name of the member with the
1965 usual XML tag translation, see [colon notation](#toxsd2).
1966 
1967 To override the standard translation of identifier names to XML tag names of
1968 attributes and elements, add the XML tag name in backticks (requires gSOAP
1969 2.8.30 and later versions):
1970 
1971 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
1972  class ns__record
1973  {
1974  public:
1975  @std::string name `full-name`;
1976  @uint64_t SSN `tax-id`;
1977  ns__record *spouse `married-to`;
1978  };
1979 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1980 
1981 This class maps to a complexType in the soapcpp2-generated schema:
1982 
1983  <complexType name="record">
1984  <sequence>
1985  <element name="married-to" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/>
1986  </sequence>
1987  <attribute name="full-name" type="xsd:string" use="required"/>
1988  <attribute name="tax-id" type="xsd:unsignedLong" use="required"/>
1989  </complexType>
1990 
1991 An example XML instance of `ns__record` is:
1992 
1993  <ns:record xmlns:ns="urn:types" full-name="Joe" tax-id="1234567890">
1994  <married-to full-name="Jane" tax-id="1987654320">
1995  </married-to>
1996  </ns:record>
1997 
1998 A backtick XML tag name may contain any non-empty sequence of ASCII and UTF-8
1999 characters except white space and the backtick character. A backtick tag can
2000 be combined with member constraints and default member initializers:
2001 
2002  @uint64_t SSN `tax-id` 0:1 = 999;
2003 
2004 ### Qualified and unqualified members {#toxsd9-6}
2005 
2006 Class, struct, and union data members are mapped to namespace qualified or
2007 unqualified tag names of local elements and attributes. If a data member has
2008 no prefix then the default form of qualification is applied based on the
2009 element/attribute form that is declared with the schema of the class, struct,
2010 or union type. If the member name has a namespace prefix by colon notation,
2011 then the prefix overrules the default (un)qualified form. Therefore,
2012 [colon notation](#toxsd2) is an effective mechanism to control qualification of
2013 tag names of individual members of classes, structs, and unions.
2014 
2015 The XML schema elementFormDefault and attributeFormDefault declarations control
2016 the tag name qualification of local elements and attributes, respectively.
2017 
2018 - "unqualified" indicates that local elements/attributes are not qualified with
2019  the namespace prefix.
2020 
2021 - "qualified" indicates that local elements/attributes must be qualified with
2022  the namespace prefix.
2023 
2024 Individual schema declarations of local elements and attributes may overrule
2025 this by using the form declaration in a schema and by using colon notation to
2026 add namespace prefixes to class, struct, and union members in the header file
2027 for soapcpp2.
2028 
2029 Consider for example an `ns__record` class in the `ns` namespace in which local
2030 elements are qualified and local attributes are unqualified by default:
2031 
2032 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2033  //gsoap ns schema namespace: urn:types
2034  //gsoap ns schema elementForm: qualified
2035  //gsoap ns schema attributeForm: unqualified
2036  class ns__record
2037  {
2038  public:
2039  @std::string name;
2040  @uint64_t SSN;
2041  ns__record *spouse;
2042  };
2043 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2044 
2045 This class maps to a complexType in the soapcpp2-generated schema with
2046 targetNamespace "urn:types", elementFormDefault qualified and
2047 attributeFormDefault unqualified:
2048 
2049  <schema targetNamespace="urn:types"
2050  ...
2051  elementFormDefault="qualified"
2052  attributeFormDefault="unqualified"
2053  ... >
2054  <complexType name="record">
2055  <sequence>
2056  <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/>
2057  </sequence>
2058  <attribute name="name" type="xsd:string" use="required"/>
2059  <attribute name="SSN" type="xsd:unsignedLong" use="required"/>
2060  </complexType>
2061  </schema>
2062 
2063 An example XML instance of `ns__record` is:
2064 
2065  <ns:record xmlns:ns="urn:types" name="Joe" SSN="1234567890">
2066  <ns:spouse> name="Jane" SSN="1987654320">
2067  </ns:spouse>
2068  </ns:record>
2069 
2070 Note that the root element ns:record is qualified because it is a root element
2071 of the schema with target namespace "urn:types". Its local element ns:spouse
2072 is namespace qualified because the elementFormDefault of local elements is
2073 qualified. Attributes are unqualified.
2074 
2075 The default namespace (un)qualification of local elements and attributes can be
2076 overruled by adding a prefix to the member name by using colon notation:
2077 
2078 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2079  //gsoap ns schema namespace: urn:types
2080  //gsoap ns schema elementForm: qualified
2081  //gsoap ns schema attributeForm: unqualified
2082  class ns__record
2083  {
2084  public:
2085  @std::string ns:name; // 'ns:' qualified
2086  @uint64_t SSN;
2087  ns__record *:spouse; // ':' unqualified (empty prefix)
2088  };
2089 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2090 
2091 The colon notation for member `ns:name` forces qualification of its attribute
2092 tag in XML. The colon notation for member `:spouse` removes qualification from
2093 its local element tag:
2094 
2095  <schema targetNamespace="urn:types"
2096  ...
2097  elementFormDefault="unqualified"
2098  attributeFormDefault="unqualified"
2099  ... >
2100  <complexType name="record">
2101  <sequence>
2102  <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true" form="unqualified"/>
2103  </sequence>
2104  <attribute name="name" type="xsd:string" use="required" form="qualified"/>
2105  <attribute name="SSN" type="xsd:unsignedLong" use="required"/>
2106  </complexType>
2107  </schema>
2108 
2109 XML instances of `ns__record` have unqualified spouse elements and qualified
2110 ns:name attributes:
2111 
2112  <ns:record xmlns:ns="urn:types" ns:name="Joe" SSN="1234567890">
2113  <spouse> ns:name="Jane" SSN="1987654320">
2114  </spouse>
2115  </ns:record>
2116 
2117 Note that data members can also be prefixed using the `prefix__name`
2118 convention. However, this has a different effect by referring to global (root)
2119 elements and attributes, see [document root element definitions](#toxsd9-7).
2120 
2121 [Backtick tag names](#toxsd9-5) can be used in place of the member name
2122 annotations and will achieve the same effect as described when these tag names
2123 are (un)qualified (requires gSOAP 2.8.30 and later versions).
2124 
2125 @note You must declare a target namespace with a `//gsoap ns schema namespace:`
2126 directive to enable the `elementForm` and `attributeForm` directives in order
2127 to generate valid schemas with soapcpp2. See [directives](#directives) for
2128 more details.
2129 
2130 ### Defining document root elements {#toxsd9-7}
2131 
2132 To define and reference XML document root elements we use type names that start
2133 with an underscore:
2134 
2135 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2136  class _ns__record
2137 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2138 
2139 Alternatively, we can use a typedef to define a document root element with a
2140 given type:
2141 
2142 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2143  typedef ns__record _ns__record;
2144 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2145 
2146 This typedef maps to a global root element that is added to the
2147 soapcpp2-generated schema:
2148 
2149  <element name="record" type="ns:record"/>
2150 
2151 An example XML instance of `_ns__record` is:
2152 
2153  <ns:record xmlns:ns="urn:types">
2154  <name>Joe</name>
2155  <SSN>1234567890</SSN>
2156  <spouse>
2157  <name>Jane</name>
2158  <SSN>1987654320</SSN>
2159  </spouse>
2160  </ns:record>
2161 
2162 Global-level element/attribute definitions are also referenced and/or added to
2163 the generated schema when serializable data members reference these by their
2164 qualified name:
2165 
2166 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2167  typedef std::string _ns__name 1 : 100;
2168  class _ns__record
2169  {
2170  public:
2171  @_QName xsi__type; // built-in XSD attribute xsi:type
2172  _ns__name ns__name; // ref to global ns:name element
2173  uint64_t SSN;
2174  _ns__record *spouse;
2175  };
2176 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2177 
2178 These types map to the following comonents in the soapcpp2-generated schema:
2179 
2180  <simpleType name="name">
2181  <restriction base="xsd:string">
2182  <minLength value="1"/>
2183  <maxLength value="100"/>
2184  </restriction>
2185  </simpleType>
2186  <element name="name" type="ns:name"/>
2187  <complexType name="record">
2188  <sequence>
2189  <element ref="ns:name" minOccurs="1" maxOccurs="1"/>
2190  <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1"/>
2191  <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/>
2192  </sequence>
2193  <attribute ref="xsi:type" use="optional"/>
2194  </complexType>
2195  <element name="record" type="ns:record"/>
2196 
2197 Use only use qualified member names when their types match the global-level
2198 element types that they refer to. For example:
2199 
2200 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2201  typedef std::string _ns__name; // global element ns:name of type xsd:string
2202  class _ns__record
2203  {
2204  public:
2205  int ns__name; // BAD: global element ns:name is NOT type int
2206  _ns__record ns__record; // OK: ns:record is a global-level root element
2207  ...
2208  };
2209 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2210 
2211 Therefore, we recommend to use qualified member names only when necessary to
2212 refer to standard XSD elements and attributes, such as `xsi__type`, and
2213 `xsd__lang`.
2214 
2215 By contrast, colon notation has the desired effect to (un)qualify local tag
2216 names by overruling the default element/attribute namespace qualification, see
2217 [qualified and unqualified members](#toxsd9-6).
2218 
2219 As an alternative to prefixing member names, use the backtick tag (requires
2220 gSOAP 2.8.30 and later versions):
2221 
2222 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2223  typedef std::string _ns__name 1 : 100;
2224  class _ns__record
2225  {
2226  public:
2227  @_QName t `xsi:type`; // built-in XSD attribute xsi:type
2228  _ns__name s `ns:name`; // ref to global ns:name element
2229  uint64_t SSN;
2230  _ns__record *spouse;
2231  };
2232 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2233 
2234 ### (Smart) pointer members and their occurrence constraints {#toxsd9-8}
2235 
2236 A public pointer-typed data member is serialized by following its (smart)
2237 pointer(s) to the value pointed to. To serialize pointers to dynamic arrays of
2238 data, please see the next section on
2239 [container and array members and their occurrence constraints](#toxsd9-9).
2240 
2241 Pointers that are NULL and smart pointers that are empty are serialized to
2242 produce omitted element and attribute values, unless an element is required
2243 and is nillable.
2244 
2245 To control the occurrence requirements of pointer-based data members,
2246 occurrence constraints are associated with data members in the form of a range
2247 `minOccurs : maxOccurs`. For non-repeatable (meaning, not a container or array)
2248 data members, there are only three reasonable occurrence constraints:
2249 
2250 - `0:0` means that this element or attribute is prohibited.
2251 - `0:1` means that this element or attribute is optional.
2252 - `1:1` means that this element or attribute is required.
2253 
2254 Pointer-based data members have a default `0:1` occurrence constraint, making
2255 them optional, and their XML schema local element/attribute definition is
2256 marked as nillable. Non-pointer data members have a default `1:1` occurence
2257 constraint, making them required.
2258 
2259 A `nullptr` occurrence constraint may be applicable to required elements that
2260 are nillable pointer types, thus `nullptr 1:1`. This indicates that the
2261 element is nillable (can be `NULL` or `nullptr`). A pointer data member that
2262 is explicitly marked as required and nillable with `nullptr 1:1` will be
2263 serialized as an element with an `xsi:nil` attribute, thus effectively
2264 revealing the NULL property of its value.
2265 
2266 A non-pointer data member that is explicitly marked as optional with `0:1` will
2267 be set to its default value when no XML value is presented to the deserializer.
2268 A default value can be assigned to data members that have primitive types.
2269 
2270 Consider for example:
2271 
2272 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2273  class ns__record
2274  {
2275  public:
2276  std::shared_ptr<std::string> name; // optional (0:1)
2277  uint64_t SSN 0:1 = 999; // forced this to be optional with default 999
2278  ns__record *spouse 1:1; // forced this to be required (only married people)
2279  };
2280 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2281 
2282 This class maps to a complexType in the soapcpp2-generated schema:
2283 
2284  <complexType name="record">
2285  <sequence>
2286  <element name="name" type="xsd:string" minOccurs="0" maxOccurs="1" nillable="true"/>
2287  <element name="SSN" type="xsd:unsignedLong" minOccurs="0" maxOccurs="1" default="999"/>
2288  <element name="spouse" type="ns:record" minOccurs="1" maxOccurs="1" nillable="true"/>
2289  </sequence>
2290  </complexType>
2291 
2292 An example XML instance of `ns__record` with its `name` string value set to
2293 `Joe`, `SSN` set to its default, and `spouse` set to NULL:
2294 
2295  <ns:record xmlns:ns="urn:types" ...>
2296  <name>Joe</name>
2297  <SSN>999</SSN>
2298  <spouse xsi:nil="true"/>
2299  </ns:record>
2300 
2301 @note In general, a smart pointer is simply declared as a `volatile` template
2302 in a gSOAP header file for soapcpp2:
2303 
2304 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2305  volatile template <class T> class NAMESPACE::shared_ptr;
2306 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2307 
2308 @note The soapcpp2 tool generates code that uses `NAMESPACE::shared_ptr` and
2309 `NAMESPACE::make_shared` to create shared pointers to objects, where
2310 `NAMESPACE` is any valid C++ namespace such as `std` and `boost` if you have
2311 Boost installed.
2312 
2313 ### Container and array members and their occurrence constraints {#toxsd9-9}
2314 
2315 Class and struct data member types that are containers `std::deque`,
2316 `std::list`, `std::vector` and `std::set` are serialized as a collection of
2317 the values they contain. You can also serialize dynamic arrays, which is the
2318 alternative for C to store collections of data. Let's start with STL containers.
2319 
2320 You can use `std::deque`, `std::list`, `std::vector`, and `std::set` containers
2321 by importing:
2322 
2323 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2324  #import "import/stl.h" // import all containers
2325  #import "import/stldeque.h" // import deque
2326  #import "import/stllist.h" // import list
2327  #import "import/stlvector.h" // import vector
2328  #import "import/stlset.h" // import set
2329 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2330 
2331 For example, to use a vector data mamber to store names in a record:
2332 
2333 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2334  #import "import/stlvector.h"
2335  class ns__record
2336  {
2337  public:
2338  std::vector<std::string> names;
2339  uint64_t SSN;
2340  };
2341 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2342 
2343 To limit the number of names in the vector within reasonable bounds, occurrence
2344 constraints are associated with the container. Occurrence constraints are of
2345 the form `minOccurs : maxOccurs`:
2346 
2347 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2348  #import "import/stlvector.h"
2349  class ns__record
2350  {
2351  public:
2352  std::vector<std::string> names 1:10;
2353  uint64_t SSN;
2354  };
2355 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2356 
2357 This class maps to a complexType in the soapcpp2-generated schema:
2358 
2359  <complexType name="record">
2360  <sequence>
2361  <element name="name" type="xsd:string" minOccurs="1" maxOccurs="10"/>
2362  <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1""/>
2363  </sequence>
2364  </complexType>
2365 
2366 @note In general, a container is simply declared as a template in a gSOAP
2367 header file for soapcpp2. All class templates are considered containers
2368 (except when declared `volatile`, see smart pointers). For example,
2369 `std::vector` is declared in `gsoap/import/stlvector.h` as:
2370 
2371 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2372  template <class T> class std::vector;
2373 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2374 
2375 @note You can define and use your own containers. The soapcpp2 tool generates
2376 code that uses the following members of the `template <typename T> class C`
2377 container:
2378 
2379 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2380  void C::clear()
2381  C::iterator C::begin()
2382  C::const_iterator C::begin() const
2383  C::iterator C::end()
2384  C::const_iterator C::end() const
2385  size_t C::size() const
2386  C::iterator C::insert(C::iterator pos, const T& val)
2387 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2388 
2389 @note For more details see the example `simple_vector` container with
2390 documentation in the package under `gsoap/samples/template`.
2391 
2392 Because C does not support a container template library, we can use a
2393 dynamically-sized array of values. This array is declared as a size-pointer
2394 pair of members within a struct or class. The array size information is stored
2395 in a special size tag member with the name `__size` or `__sizeX`, where `X` can
2396 be any name, or by an `$int` member to identify the member as a special size
2397 tag:
2398 
2399 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2400  struct ns__record
2401  {
2402  $int sizeofnames; // array size
2403  char* *names; // array of char* names
2404  uint64_t SSN;
2405  };
2406 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2407 
2408 This class maps to a complexType in the soapcpp2-generated schema:
2409 
2410  <complexType name="record">
2411  <sequence>
2412  <element name="name" type="xsd:string" minOccurs="0" maxOccurs="unbounded" nillable="true"/>
2413  <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1""/>
2414  </sequence>
2415  </complexType>
2416 
2417 To limit the number of names in the array within reasonable bounds, occurrence
2418 constraints are associated with the array size member. Occurrence constraints
2419 are of the form `minOccurs : maxOccurs`:
2420 
2421 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2422  struct ns__record
2423  {
2424  $int sizeofnames 1:10; // array size 1..10
2425  char* *names; // array of one to ten char* names
2426  uint64_t SSN;
2427  };
2428 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2429 
2430 This class maps to a complexType in the soapcpp2-generated schema:
2431 
2432  <complexType name="record">
2433  <sequence>
2434  <element name="name" type="xsd:string" minOccurs="1" maxOccurs="10" nillable="true"/>
2435  <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1""/>
2436  </sequence>
2437  </complexType>
2438 
2439 ### Tagged union members {#toxsd9-10}
2440 
2441 A union member in a class or in a struct cannot be serialized unless a
2442 discriminating *variant selector* member is provided that tells the serializer
2443 which union field to serialize. This effectively creates a *tagged union*.
2444 
2445 The variant selector is associated with the union as a selector-union pair of members.
2446 The variant selector is a member with the name `__union` or `__unionX`, where
2447 `X` can be any name, or by an `$int` member to identify the member as a variant
2448 selector tag:
2449 
2450 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2451  class ns__record
2452  {
2453  public:
2454  $int xORnORs; // variant selector with values SOAP_UNION_fieldname
2455  union choice
2456  {
2457  float x;
2458  int n;
2459  char *s;
2460  } u;
2461  std::string name;
2462  };
2463 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2464 
2465 The variant selector values are auto-generated based on the union name `choice`
2466 and the names of its members `x`, `n`, and `s`:
2467 
2468 - `xORnORs = SOAP_UNION_choice_x` when `u.x` is valid.
2469 - `xORnORs = SOAP_UNION_choice_n` when `u.n` is valid.
2470 - `xORnORs = SOAP_UNION_choice_s` when `u.s` is valid.
2471 - `xORnORs = 0` when none are valid (should only be used with great care,
2472  because XML content validation may fail when content is required but absent).
2473 
2474 This class maps to a complexType with a sequence and choice in the
2475 soapcpp2-generated schema:
2476 
2477  <complexType name="record">
2478  <sequence>
2479  <choice>
2480  <element name="x" type="xsd:float" minOccurs="1" maxOccurs="1"/>
2481  <element name="n" type="xsd:int" minOccurs="1" maxOccurs="1"/>
2482  <element name="s" type="xsd:string" minOccurs="0" maxOccurs="1" nillable="true"/>
2483  </choice>
2484  <element name="names" type="xsd:string" minOccurs="1" maxOccurs="1" nillable="true"/>
2485  </sequence>
2486  </complexType>
2487 
2488 An STL container or dynamic array of a union requires wrapping the variant
2489 selector and union member in a struct:
2490 
2491 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2492  class ns__record
2493  {
2494  public:
2495  std::vector<
2496  struct ns__data // data with a choice of x, n, or s
2497  {
2498  $int xORnORs; // variant selector with values SOAP_UNION_fieldname
2499  union choice
2500  {
2501  float x;
2502  int n;
2503  char *s;
2504  } u;
2505  }> data; // vector with data
2506  };
2507 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2508 
2509 and an equivalent definition with a dynamic array instead of a `std::vector`
2510 (you can use this in C with structs):
2511 
2512 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2513  class ns__record
2514  {
2515  public:
2516  $int sizeOfdata; // size of dynamic array
2517  struct ns__data // data with a choice of x, n, or s
2518  {
2519  $int xORnORs; // variant selector with values SOAP_UNION_fieldname
2520  union choice
2521  {
2522  float x;
2523  int n;
2524  char *s;
2525  } u;
2526  } *data; // points to the data array of length sizeOfdata
2527  };
2528 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2529 
2530 This maps to two complexTypes in the soapcpp2-generated schema:
2531 
2532  <complexType name="data">
2533  <choice>
2534  <element name="x" type="xsd:float" minOccurs="1" maxOccurs="1"/>
2535  <element name="n" type="xsd:int" minOccurs="1" maxOccurs="1"/>
2536  <element name="s" type="xsd:string" minOccurs="0" maxOccurs="1" nillable="true"/>
2537  </choice>
2538  </complexType>
2539  <complexType name="record">
2540  <sequence>
2541  <element name="data" type="ns:data" minOccurs="0" maxOccurs="unbounded"/>
2542  </sequence>
2543  </complexType>
2544 
2545 The XML value space consists of a sequence of item elements each wrapped in an
2546 data element:
2547 
2548  <ns:record xmlns:ns="urn:types" ...>
2549  <data>
2550  <n>123</n>
2551  </data>
2552  <data>
2553  <x>3.1</x>
2554  </data>
2555  <data>
2556  <s>hello</s>
2557  </data>
2558  <data>
2559  <s>world</s>
2560  </data>
2561  </ns:record>
2562 
2563 To remove the wrapping data element, simply rename the wrapping struct and
2564 member to `__data` to make this member invisible to the serializer with the
2565 double underscore prefix naming convention. Also use a dynamic array instead
2566 of a STL container (you can use this in C with structs):
2567 
2568 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2569  class ns__record
2570  {
2571  public:
2572  $int sizeOfdata; // size of dynamic array
2573  struct __data // contains choice of x, n, or s
2574  {
2575  $int xORnORs; // variant selector with values SOAP_UNION_fieldname
2576  union choice
2577  {
2578  float x;
2579  int n;
2580  char *s;
2581  } u;
2582  } *__data; // points to the data array of length sizeOfdata
2583  };
2584 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2585 
2586 This maps to a complexType in the soapcpp2-generated schema:
2587 
2588  <complexType name="record">
2589  <sequence minOccurs="0" maxOccurs="unbounded">
2590  <choice>
2591  <element name="x" type="xsd:float" minOccurs="1" maxOccurs="1"/>
2592  <element name="n" type="xsd:int" minOccurs="1" maxOccurs="1"/>
2593  <element name="s" type="xsd:string" minOccurs="0" maxOccurs="1" nillable="true"/>
2594  </choice>
2595  </sequence>
2596  </complexType>
2597 
2598 The XML value space consists of a sequence of `<x>`, `<n>`, and/or `<s>`
2599 elements:
2600 
2601  <ns:record xmlns:ns="urn:types" ...>
2602  <n>123</n>
2603  <x>3.1</x>
2604  <s>hello</s>
2605  <s>world</s>
2606  </ns:record>
2607 
2608 Please note that structs, classes, and unions are unnested by soapcpp2 (as in
2609 the C standard of nested structs and unions). Therefore, the `choice` union in
2610 the `ns__record` class is redeclared at the top level despite its nesting
2611 within the `ns__record` class. This means that you will have to choose a
2612 unique name for each nested struct, class, and union.
2613 
2614 ### Tagged void pointer members {#toxsd9-11}
2615 
2616 To serialize data pointed to by `void*` requires run-time type information that
2617 tells the serializer what type of data to serialize by means of a *tagged void
2618 pointer*. This type information is stored in a special type tag member of a
2619 struct/class with the name `__type` or `__typeX`, where `X` can be any name, or
2620 alternatively by an `$int` special member of any name as a type tag:
2621 
2622 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2623  class ns__record
2624  {
2625  public:
2626  $int typeOfdata; // type tag with values SOAP_TYPE_T
2627  void *data; // points to some data of type T
2628  };
2629 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2630 
2631 A type tag member has nonzero values `SOAP_TYPE_T` where `T` is the name of a
2632 struct/class or the name of a primitive type, such as `int`, `std__string` (for
2633 `std::string`), `string` (for `char*`).
2634 
2635 This class maps to a complexType with a sequence in the soapcpp2-generated
2636 schema:
2637 
2638  <complexType name="record">
2639  <sequence>
2640  <element name="data" type="xsd:anyType" minOccurs="0" maxOccurs="1"/>
2641  </sequence>
2642  </complexType>
2643 
2644 The XML value space consists of the XML value space of the type with the
2645 addition of an `xsi:type` attribute to the enveloping element:
2646 
2647  <ns:record xmlns:ns="urn:types" ...>
2648  <data xsi:type="xsd:int">123</data>
2649  </ns:record>
2650 
2651 This `xsi:type` attribute is important for the receiving end to distinguish
2652 the type of data to instantiate. The receiver cannot deserialize the data
2653 without an `xsd:type` attribute.
2654 
2655 You can find the `SOAP_TYPE_T` name of each serializable type in the
2656 auto-generated soapStub.h file.
2657 
2658 Also all serializable C++ classes have a virtual `int T::soap_type()` member
2659 that returns their `SOAP_TYPE_T` value that you can use.
2660 
2661 When the `void*` pointer is NULL or when `typeOfdata` is zero, the data is not
2662 serialized.
2663 
2664 An STL container or dynamic array of `void*` pointers to `xsd:anyType` data
2665 requires wrapping the type tag and `void*` members in a struct:
2666 
2667 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2668  class ns__record
2669  {
2670  public:
2671  std::vector<
2672  struct ns__data // data with an xsd:anyType item
2673  {
2674  $int typeOfitem; // type tag with values SOAP_TYPE_T
2675  void *item; // points to some item of type T
2676  }> data; // vector with data
2677  };
2678 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2679 
2680 and an equivalent definition with a dynamic array instead of a `std::vector`
2681 (you can use this in C with structs):
2682 
2683 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2684  class ns__record
2685  {
2686  public:
2687  $int sizeOfdata; // size of dynamic array
2688  struct ns__data // data with an xsd:anyType item
2689  {
2690  $int typeOfitem; // type tag with values SOAP_TYPE_T
2691  void *item; // points to some item of type T
2692  } *data; // points to the data array of length sizeOfdata
2693  };
2694 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2695 
2696 This maps to two complexTypes in the soapcpp2-generated schema:
2697 
2698  <complexType name="data">
2699  <sequence>
2700  <element name="item" type="xsd:anyType" minOccurs="1" maxOccurs="1" nillable="true"/>
2701  </sequence>
2702  </complexType>
2703  <complexType name="record">
2704  <sequence>
2705  <element name="data" type="ns:data" minOccurs="0" maxOccurs="unbounded"/>
2706  </sequence>
2707  </complexType>
2708 
2709 The XML value space consists of a sequence of item elements each wrapped in a
2710 data element:
2711 
2712  <ns:record xmlns:ns="urn:types" ...>
2713  <data>
2714  <item xsi:type="xsd:int">123</item>
2715  </data>
2716  <data>
2717  <item xsi:type="xsd:double">3.1</item>
2718  </data>
2719  <data>
2720  <item xsi:type="xsd:string">abc</item>
2721  </data>
2722  </ns:record>
2723 
2724 To remove the wrapping data elements, simply rename the wrapping struct and
2725 member to `__data` to make this member invisible to the serializer with the
2726 double underscore prefix naming convention. Also use a dynamic array instead
2727 of a STL container (you can use this in C with structs):
2728 
2729 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2730  class ns__record
2731  {
2732  public:
2733  $int sizeOfdata; // size of dynamic array
2734  struct __data // contains xsd:anyType item
2735  {
2736  $int typeOfitem; // type tag with values SOAP_TYPE_T
2737  void *item; // points to some item of type T
2738  } *__data; // points to the data array of length sizeOfdata
2739  };
2740 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2741 
2742 This maps to a complexType in the soapcpp2-generated schema:
2743 
2744  <complexType name="record">
2745  <sequence minOccurs="0" maxOccurs="unbounded">
2746  <element name="item" type="xsd:anyType" minOccurs="1" maxOccurs="1"/>
2747  </sequence>
2748  </complexType>
2749 
2750 The XML value space consists of a sequence of data elements:
2751 
2752  <ns:record xmlns:ns="urn:types" ...>
2753  <item xsi:type="xsd:int">123</item>
2754  <item xsi:type="xsd:double">3.1</item>
2755  <item xsi:type="xsd:string">abc</item>
2756  </ns:record>
2757 
2758 Again, please note that structs, classes, and unions are unnested by soapcpp2
2759 (as in the C standard of nested structs and unions). Therefore, the `__data`
2760 struct in the `ns__record` class is redeclared at the top level despite its
2761 nesting within the `ns__record` class. This means that you will have to choose
2762 a unique name for each nested struct, class, and union.
2763 
2764 @see Section [XSD type bindings](#typemap2).
2765 
2766 ### Adding get and set methods {#toxsd9-12}
2767 
2768 A public `get` method may be added to a class or struct, which will be
2769 triggered by the deserializer. This method will be invoked right after the
2770 instance is populated by the deserializer. The `get` method can be used to
2771 update or verify deserialized content. It should return `SOAP_OK` or set
2772 `soap::error` to a nonzero error code and return it.
2773 
2774 A public `set` method may be added to a class or struct, which will be
2775 triggered by the serializer. The method will be invoked just before the
2776 instance is serialized. Likewise, the `set` method should return `SOAP_OK` or
2777 set set `soap::error` to a nonzero error code and return it.
2778 
2779 For example, adding a `set` and `get` method to a class declaration:
2780 
2781 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2782  class ns__record
2783  {
2784  public:
2785  int set(struct soap*); // triggered before serialization
2786  int get(struct soap*); // triggered after deserialization
2787  ...
2788  };
2789 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2790 
2791 To add these and othe rmethods to classes and structs with wsdl2h and
2792 `typemap.dat`, please see [class/struct member additions](#typemap3).
2793 
2794 ### Operations on classes and structs {#toxsd9-13}
2795 
2796 The following functions/macros are generated by soapcpp2 for each type `T`,
2797 which should make it easier to send, receive, and copy XML data in C and in
2798 C++:
2799 
2800 - `int soap_write_T(struct soap*, T*)` writes an instance of `T` to a file via
2801  file descriptor `int soap::sendfd)` or to a stream via `std::ostream
2802  *soap::os` (C++ only) or saves into a NUL-terminated string by setting
2803  `const char **soap::os` to a string pointer to be set (C only). Returns
2804  `SOAP_OK` on success or an error code, also stored in `soap->error`.
2805 
2806 - `int soap_read_T(struct soap*, T*)` reads an instance of `T` from a file via
2807  file descriptor `int soap::recvfd)` or from a stream via `std::istream
2808  *soap::is` (C++ only) or reads from a NUL-termianted string `const char
2809  *soap::is` (C only). Returns `SOAP_OK` on success or an error code, also
2810  stored in `soap->error`.
2811 
2812 - `void soap_default_T(struct soap*, T*)` sets an instance `T` to its default
2813  value, resetting members of a struct to their initial values (for classes we
2814  use method `T::soap_default`, see below).
2815 
2816 - `T * soap_dup_T(struct soap*, T *dst, const T *src)` (soapcpp2 option `-Ec`)
2817  deep copy `src` into `dst`, replicating all deep cycles and shared pointers
2818  when a managing soap context is provided as argument. When `dst` is NULL,
2819  allocates space for `dst`. Deep copy is a tree when argument is NULL, but the
2820  presence of deep cycles will lead to non-termination. Use flag
2821  `SOAP_XML_TREE` with managing context to copy into a tree without cycles and
2822  pointers to shared objects. Returns `dst` (or allocated space when `dst` is
2823  NULL).
2824 
2825 - `void soap_del_T(const T*)` (soapcpp2 option `-Ed`) deletes all
2826  heap-allocated members of this object by deep deletion ONLY IF this object
2827  and all of its (deep) members are not managed by a soap context AND the deep
2828  structure is a tree (no cycles and co-referenced objects by way of multiple
2829  (non-smart) pointers pointing to the same data). Can be safely used after
2830  `soap_dup(NULL)` to delete the deep copy. Does not delete the object itself.
2831 
2832 When in C++ mode, soapcpp2 tool adds several methods to classes in addition to
2833 adding a default constructor and destructor (when these were not explicitly
2834 declared).
2835 
2836 The public methods added to a class `T`:
2837 
2838 - `virtual int T::soap_type(void)` returns a unique type ID (`SOAP_TYPE_T`).
2839  This numeric ID can be used to distinguish base from derived instances.
2840 
2841 - `virtual void T::soap_default(struct soap*)` sets all data members to
2842  default values.
2843 
2844 - `virtual void T::soap_serialize(struct soap*) const` serializes object to
2845  prepare for SOAP 1.1/1.2 encoded output (or with `SOAP_XML_GRAPH`) by
2846  analyzing its (cyclic) structures.
2847 
2848 - `virtual int T::soap_put(struct soap*, const char *tag, const char *type) const`
2849  emits object in XML, compliant with SOAP 1.1 encoding style, return error
2850  code or `SOAP_OK`. Requires `soap_begin_send(soap)` and
2851  `soap_end_send(soap)`.
2852 
2853 - `virtual int T::soap_out(struct soap*, const char *tag, int id, const char *type) const`
2854  emits object in XML, with tag and optional id attribute and `xsi:type`,
2855  return error code or `SOAP_OK`. Requires `soap_begin_send(soap)` and
2856  `soap_end_send(soap)`.
2857 
2858 - `virtual void * T::soap_get(struct soap*, const char *tag, const char *type)`
2859  Get object from XML, compliant with SOAP 1.1 encoding style, return pointer
2860  to object or NULL on error. Requires `soap_begin_recv(soap)` and
2861  `soap_end_recv(soap)`.
2862 
2863 - `virtual void *soap_in(struct soap*, const char *tag, const char *type)`
2864  Get object from XML, with matching tag and type (NULL matches any tag and
2865  type), return pointer to object or NULL on error. Requires
2866  `soap_begin_recv(soap)` and `soap_end_recv(soap)`
2867 
2868 - `virtual T * T::soap_alloc(void) const` returns a new object of type `T`,
2869  default initialized and not managed by a soap context.
2870 
2871 - `virtual T * T::soap_dup(struct soap*) const` (soapcpp2 option `-Ec`) returns
2872  a duplicate of this object by deep copying, replicating all deep cycles and
2873  shared pointers when a managing soap context is provided as argument. Deep
2874  copy is a tree when argument is NULL, but the presence of deep cycles will
2875  lead to non-termination. Use flag `SOAP_XML_TREE` with the managing context
2876  to copy into a tree without cycles and pointers to shared objects.
2877 
2878 - `virtual void T::soap_del() const` (soapcpp2 option `-Ed`) deletes all
2879  heap-allocated members of this object by deep deletion ONLY IF this object
2880  and all of its (deep) members are not managed by a soap context AND the deep
2881  structure is a tree (no cycles and co-referenced objects by way of multiple
2882  (non-smart) pointers pointing to the same data). Can be safely used after
2883  `soap_dup(NULL)` to delete the deep copy. Does not delete the object itself.
2884 
2885 Also for C++, there are four variations of `soap_new_T` for
2886 class/struct/template type `T` that soapcpp2 auto-generates to create instances
2887 on a context-managed heap:
2888 
2889 - `T * soap_new_T(struct soap*)` returns a new instance of `T` with default data
2890  member initializations that are set with the soapcpp2 auto-generated `void
2891  T::soap_default(struct soap*)` method), but ONLY IF the soapcpp2
2892  auto-generated default constructor is used that invokes `soap_default()` and
2893  was not replaced by a user-defined default constructor.
2894 
2895 - `T * soap_new_T(struct soap*, int n)` returns an array of `n` new instances of
2896  `T`. Similar to the above, instances are initialized.
2897 
2898 - `T * soap_new_req_T(struct soap*, ...)` returns a new instance of `T` and sets
2899  the required data members to the values specified in `...`. The required data
2900  members are those with nonzero minOccurs, see the subsections on
2901  [(smart) pointer members and their occurrence constraints](#toxsd9-8) and
2902  [container and array members and their occurrence constraints](#toxsd9-9).
2903 
2904 - `T * soap_new_set_T(struct soap*, ...)` returns a new instance of `T` and sets
2905  the public/serializable data members to the values specified in `...`.
2906 
2907 The above functions can be invoked with a NULL `soap` context, but we will be
2908 responsible to use `delete T` to remove this instance from the unmanaged heap.
2909 
2910 Special classes and structs {#toxsd10}
2911 ---------------------------
2912 
2913 ### SOAP encoded arrays {#toxsd10-1}
2914 
2915 A class or struct with the following layout is a one-dimensional SOAP encoded
2916 Array type:
2917 
2918 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2919  class ArrayOfT
2920  {
2921  public:
2922  T *__ptr; // array pointer
2923  int __size; // array size
2924  };
2925 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2926 
2927 where `T` is the array element type. A multidimensional SOAP Array is:
2928 
2929 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2930  class ArrayOfT
2931  {
2932  public:
2933  T *__ptr; // array pointer
2934  int __size[N]; // array size of each dimension
2935  };
2936 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2937 
2938 where `N` is the constant number of dimensions. The pointer points to an array
2939 of `__size[0]*__size[1]* ... * __size[N-1]` elements.
2940 
2941 This maps to a complexType restriction of SOAP-ENC:Array in the
2942 soapcpp2-generated schema:
2943 
2944  <complexType name="ArrayOfT">
2945  <complexContent>
2946  <restriction base="SOAP-ENC:Array">
2947  <sequence>
2948  <element name="item" type="T" minOccurs="0" maxOccurs="unbounded" nillable="true"/>
2949  </sequence>
2950  <attribute ref="SOAP-ENC:arrayType" WSDL:arrayType="ArrayOfT[]"/>
2951  </restriction>
2952  </complexContent>
2953  </complexType>
2954 
2955 The name of the class can be arbitrary. We often use `ArrayOfT` without a
2956 prefix to distinguish arrays from other classes and structs.
2957 
2958 With SOAP 1.1 encoding, an optional offset member can be added that controls
2959 the start of the index range for each dimension:
2960 
2961 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2962  class ArrayOfT
2963  {
2964  public:
2965  T *__ptr; // array pointer
2966  int __size[N]; // array size of each dimension
2967  int __offset[N]; // array offsets to start each dimension
2968  };
2969 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2970 
2971 For example, we can define a matrix of floats as follows:
2972 
2973 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2974  class Matrix
2975  {
2976  public:
2977  double *__ptr;
2978  int __size[2];
2979  };
2980 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2981 
2982 The following code populates the matrix and serializes it in XML:
2983 
2984 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
2985  soap *soap = soap_new1(SOAP_XML_INDENT);
2986  Matrix A;
2987  double a[6] = { 1, 2, 3, 4, 5, 6 };
2988  A.__ptr = a;
2989  A.__size[0] = 2;
2990  A.__size[1] = 3;
2991  soap_write_Matrix(soap, &A);
2992 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2993 
2994 Matrix A is serialized as an array with 2x3 values:
2995 
2996  <SOAP-ENC:Array SOAP-ENC:arrayType="xsd:double[2,3]" ...>
2997  <item>1</item>
2998  <item>2</item>
2999  <item>3</item>
3000  <item>4</item>
3001  <item>5</item>
3002  <item>6</item>
3003  </SOAP-ENC:Array>
3004 
3005 ### XSD hexBinary and base64Binary types {#toxsd10-2}
3006 
3007 A special case of a one-dimensional array is used to define `xsd:hexBinary` and
3008 `xsd:base64Binary` types when the pointer type is `unsigned char`:
3009 
3010 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3011  class xsd__hexBinary
3012  {
3013  public:
3014  unsigned char *__ptr; // points to raw binary data
3015  int __size; // size of data
3016  };
3017 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3018 
3019 and
3020 
3021 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3022  class xsd__base64Binary
3023  {
3024  public:
3025  unsigned char *__ptr; // points to raw binary data
3026  int __size; // size of data
3027  };
3028 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3029 
3030 ### MIME/MTOM attachment binary types {#toxsd10-3}
3031 
3032 A class or struct with a binary content layout can be extended to support
3033 MIME/MTOM (and older DIME) attachments, such as in xop:Include elements:
3034 
3035 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3036  //gsoap xop schema import: http://www.w3.org/2004/08/xop/include
3037  class _xop__Include
3038  {
3039  public:
3040  unsigned char *__ptr; // points to raw binary data
3041  int __size; // size of data
3042  char *id; // NULL to generate an id, or set to a unique UUID
3043  char *type; // MIME type of the data
3044  char *options; // optional description of MIME attachment
3045  };
3046 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3047 
3048 Attachments are beyond the scope of this document. The `SOAP_ENC_MIME` and
3049 `SOAP_ENC_MTOM` context flag must be set to enable attachments. See the
3050 [gSOAP user guide](http://www.genivia.com/doc/soapdoc2.html) for more details.
3051 
3052 ### Wrapper class/struct with simpleContent {#toxsd10-4}
3053 
3054 A class or struct with the following layout is a complexType that wraps
3055 simpleContent:
3056 
3057 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3058  class ns__simple
3059  {
3060  public:
3061  T __item;
3062  };
3063 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3064 
3065 The type `T` is a primitive type (`bool`, `enum`, `time_t`, numeric and string
3066 types), `xsd__hexBinary`, `xsd__base64Binary`, and custom serializers, such as
3067 `xsd__dateTime`.
3068 
3069 This maps to a complexType with simpleContent in the soapcpp2-generated schema:
3070 
3071  <complexType name="simple">
3072  <simpleContent>
3073  <extension base="T"/>
3074  </simpleContent>
3075  </complexType>
3076 
3077 A wrapper class/struct may include any number of attributes declared with `@`.
3078 
3079 ### DOM anyType and anyAttribute {#toxsd10-5}
3080 
3081 Use of a DOM is optional and enabled by `#import "dom.h"` to use the DOM
3082 `xsd__anyType` element node and `xsd__anyAttribute` attribute node:
3083 
3084 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3085  #import "dom.h"
3086 
3087  class ns__record
3088  {
3089  public:
3090  @xsd__anyAttribute attributes; // list of DOM attributes
3091  ...
3092  xsd__anyType *name; // optional DOM element
3093  };
3094 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3095 
3096 where `name` contains XML stored in a DOM node set and `attributes` is a list
3097 of all visibly rendered attributes. The name `attributes` is arbitrary and any
3098 name will suffice.
3099 
3100 You should place the `xsd__anyType` members at the end of the struct or class.
3101 This ensures that the DOM members are populated last as a "catch all". A
3102 member name starting with double underscore is a wildcard member name and
3103 matches any XML tag. These members are placed at the end of a struct or class
3104 automatically by soapcpp2.
3105 
3106 An `#import "dom.h"` import is automatically added by wsdl2h with option `-d`
3107 to bind `xsd:anyType` to DOM nodes, and also to populate `xsd:any`,
3108 `xsd:anyAttribute` and `xsd:mixed` XML content:
3109 
3110 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3111  #import "dom.h"
3112 
3113  class ns__record
3114  {
3115  public:
3116  ...
3117  @xsd__anyAttribute __anyAttribute; // optional DOM attributes
3118  std::vector<xsd__anyType> __any 0; // optional DOM elements
3119  xsd__anyType __mixed 0; // optional mixed content
3120  };
3121 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3122 
3123 where the members prefixed with `__` are "invisible" to the XML parser, meaning
3124 that these members are not bound to XML tag names.
3125 
3126 In C you can use a dynamic arrary instead of `std::vector`:
3127 
3128 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.c}
3129  #import "dom.h"
3130 
3131  struct ns__record
3132  {
3133  ...
3134  @xsd__anyAttribute __anyAttribute; // optional DOM attributes
3135  $int __sizeOfany; // size of the array
3136  xsd__anyType *__any; // optional DOM elements
3137  xsd__anyType __mixed 0; // optional mixed content
3138  };
3139 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3140 
3141 Classes can inherit DOM, which enables full use of polymorphism with one base
3142 DOM class:
3143 
3144 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3145  #import "dom.h"
3146 
3147  class ns__record : public xsd__anyType
3148  {
3149  ...
3150  std::vector<xsd__anyType*> array; // array of objects of any class
3151  };
3152 
3153 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3154 
3155 This permits an `xsd__anyType` pointer to refer to a derived class such as
3156 `ns__record`, which will be serialized with an `xsi:type` attribute that is
3157 set to "ns:record". The `xsi:type` attributes add the necessary type information
3158 to distinguish the XML content from the DOM base type. This is important for
3159 the receiving end: without `xsd:type` attributes with type names, only base DOM
3160 objects are recognized and instantiated.
3161 
3162 Because C lacks OOP principles such as class inheritance and polymorphism, you
3163 will need to use the special [`void*` members](#toxsd9-11) to serialize data
3164 pointed to by a `void*` member.
3165 
3166 To ensure that wsdl2h generates pointer-based `xsd__anyType` DOM nodes with
3167 option `-d` for `xsd:any`, add the following line to `typemap.dat`:
3168 
3169  xsd__any = | xsd__anyType*
3170 
3171 This lets wsdl2h produce class/struct members and containers with
3172 `xsd__anyType*` for `xsd:any` instead of `xsd__anyType`. To just force all
3173 `xsd:anyType` uses to be pointer-based, declare in `typemap.dat`:
3174 
3175  xsd__anyType = | xsd__anyType*
3176 
3177 If you use wsdl2h with option `-p` with option `-d` then every class will
3178 inherit DOM as shown above. Without option `-d`, an `xsd__anyType` type is
3179 generated to serve as the root type in the type hierarchy:
3180 
3181 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3182  class xsd__anyType { _XML __item; struct soap *soap; };
3183 
3184  class ns__record : public xsd__anyType
3185  {
3186  ...
3187  };
3188 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3189 
3190 where the `_XML __item` member holds any XML content as a literal XML string.
3191 
3192 To use the DOM API, compile `dom.c` (or `dom.cpp` for C++), or link with
3193 `-lgsoapssl` (or `-lgsoapssl++` for C++).
3194 
3195 @see Documentation of [XML DOM and XPath](http://www.genivia.com/doc/dom/html)
3196 for more details.
3197 
3198 Directives {#directives}
3199 ==========
3200 
3201 You can use `//gsoap` directives in the gSOAP header file with the data binding
3202 interface for soapcpp2. These directives are used to configure the code
3203 generated by soapcpp2 by declaring various. properties of Web services and XML
3204 schemas. When using the wsdl2h tool, you will notice that wsdl2h generates
3205 directives automatically based on the WSDL and XSD input.
3206 
3207 Service directives are applicable to service and operations described by WSDL.
3208 Schema directives are applicable to types, elements, and attributes defined by
3209 XML schemas.
3210 
3211 Service directives {#directives-1}
3212 ------------------
3213 
3214 A service directive must start at a new line and is of the form:
3215 
3216 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3217  //gsoap <prefix> service <property>: <value>
3218 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3219 
3220 where `<prefix>` is the XML namespace prefix of a service binding. The
3221 `<property>` and `<value>` fields are one of the following:
3222 
3223 | Property | Value |
3224 | --------------- | -------------------------------------------------------------------------------- |
3225 | `name` | name of the service, optionally followed by text describing the service |
3226 | `namespace` | URI of the WSDL targetNamespace |
3227 | `documentation` | text describing the service (see also the `name` property), multiple permitted |
3228 | `doc` | same as above, shorthand form |
3229 | `style` | `document` (default) SOAP messaging style or `rpc` for SOAP RPC |
3230 | `encoding` | `literal` (default), `encoded` for SOAP encoding, or a custom URI |
3231 | `protocol` | specifies SOAP or REST, see below |
3232 | `port` | URL of the service endpoint, usually an http or https address |
3233 | `transport` | URI declaration of the transport, usually `http://schemas.xmlsoap.org/soap/http` |
3234 | `definitions` | name of the WSDL definitions/\@name |
3235 | `type` | name of the WSDL definitions/portType/\@name (WSDL2.0 interface/\@name) |
3236 | `binding` | name of the WSDL definitions/binding/\@name |
3237 | `portName` | name of the WSDL definitions/service/port/\@name |
3238 | `portType` | an alias for the `type` property |
3239 | `interface` | an alias for the `type` property |
3240 | `location` | an alias for the `port` property |
3241 | `endpoint` | an alias for the `port` property |
3242 
3243 The service `name` and `namespace` properties are required in order to generate
3244 a valid WSDL with soapcpp2. The other properties are optional.
3245 
3246 The `style` and `encoding` property defaults are changed with soapcpp2 option
3247 `-e` to `rpc` and `encoded`, respectively.
3248 
3249 The `protocol` property is `SOAP` by default (SOAP 1.1). Protocol property
3250 values are:
3251 
3252 | Protocol Value | Description |
3253 | -------------- | ---------------------------------------------------- |
3254 | `SOAP` | SOAP transport, supporting both SOAP 1.1 and 1.2 |
3255 | `SOAP1.1` | SOAP 1.1 transport (same as soapcpp2 option `-1`) |
3256 | `SOAP1.2` | SOAP 1.2 transport (same as soapcpp2 option `-2`) |
3257 | `SOAP-GET` | one-way SOAP 1.1 or 1.2 with HTTP GET |
3258 | `SOAP1.1-GET` | one-way SOAP 1.1 with HTTP GET |
3259 | `SOAP1.2-GET` | one-way SOAP 1.2 with HTTP GET |
3260 | `HTTP` | non-SOAP REST protocol with HTTP POST |
3261 | `POST` | non-SOAP REST protocol with HTTP POST |
3262 | `GET` | non-SOAP REST protocol with HTTP GET |
3263 | `PUT` | non-SOAP REST protocol with HTTP PUT |
3264 | `DELETE` | non-SOAP REST protocol with HTTP DELETE |
3265 
3266 You can bind service operations to the WSDL namespace of a service by using the
3267 namespace prefix as part of the identifier name of the function that defines
3268 the service operation:
3269 
3270 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3271  int prefix__func(arg1, arg2, ..., argn, result);
3272 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3273 
3274 You can override the `port` endpoint URL at runtime in the auto-generated
3275 `soap_call_prefix__func` service call (C/C++ client side) and in the C++ proxy
3276 class service call.
3277 
3278 Service method directives {#directives-2}
3279 -------------------------
3280 
3281 Service properties are applicable to a service and to all of its operations.
3282 Service method directives are specifically applicable to a service operation.
3283 
3284 A service method directive is of the form:
3285 
3286 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3287  //gsoap <prefix> service method-<property>: <method> <value>
3288 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3289 
3290 where `<prefix>` is the XML namespace prefix of a service binding and
3291 `<method>` is the unqualified name of a service operation. The `<property>`
3292 and `<value>` fields are one of the following:
3293 
3294 | Method Property | Value |
3295 | --------------------------- | ------------------------------------------------------------------------------ |
3296 | `method-documentation` | text describing the service operation |
3297 | `method` | same as above, shorthand form |
3298 | `method-action` | `""` or URI SOAPAction HTTP header, or URL query string for REST protocols |
3299 | `method-input-action` | `""` or URI SOAPAction HTTP header of service request messages |
3300 | `method-output-action` | `""` or URI SOAPAction HTTP header of service response messages |
3301 | `method-fault-action` | `""` or URI SOAPAction HTTP header of service fault messages |
3302 | `method-header-part` | member name of the `SOAP_ENV__Header` struct used in SOAP Header |
3303 | `method-input-header-part` | member name of the `SOAP_ENV__Header` struct used in SOAP Headers of requests |
3304 | `method-output-header-part` | member name of the `SOAP_ENV__Header` struct used in SOAP Headers of responses |
3305 | `method-fault` | type name of a struct or class member used in `SOAP_ENV__Details` struct |
3306 | `method-mime-type` | REST content type or SOAP MIME attachment content type(s) |
3307 | `method-input-mime-type` | REST content type or SOAP MIME attachment content type(s) of request message |
3308 | `method-output-mime-type` | REST content type or SOAP MIME attachment content type(s) of response message |
3309 | `method-style` | `document` or `rpc` |
3310 | `method-encoding` | `literal`, `encoded`, or a custom URI for encodingStyle of messages |
3311 | `method-response-encoding` | `literal`, `encoded`, or a custom URI for encodingStyle of response messages |
3312 | `method-protocol` | SOAP or REST, see [service directives](#directives-1) |
3313 
3314 The `method-header-part` properties can be repeated for a service operation to
3315 declare multiple SOAP Header parts that the service operation requires. You
3316 can use `method-input-header-part` and `method-output-header-part` to
3317 differentiate between request and response messages.
3318 
3319 The `method-fault` property can be repeated for a service operation to declare
3320 multiple faults that the service operation may return.
3321 
3322 The `method-action` property serves two purposes:
3323 
3324 -# To set the SOAPAction header for SOAP protocols, i.e. sets the
3325  definitions/binding/operation/SOAP:operation/\@soapAction.
3326 
3327 -# To set the URL query string for endpoints with REST protocols, i.e. sets the
3328  definitions/binding/operation/HTTP:operation/\@location, which specifies
3329  a URL query string (starts with a `?`) to complete the service endpoint URL
3330  or extends the endpoint URL with a local path (starts with a `/`).
3331 
3332 Use `method-input-action` and `method-output-action` to differentiate the
3333 SOAPAction between SOAP request and response messages.
3334 
3335 You can always override the port endpoint URL and action values at runtime in
3336 the auto-generated `soap_call_prefix__func` service call (C/C++ client side)
3337 and in the auto-generated C++ proxy class service calls. A runtime NULL
3338 endpoint URL and/or action uses the defaults set by these directives.
3339 
3340 The `method-mime-type` property serves two purposes:
3341 
3342 -# To set the type of MIME/MTOM attachments used with SOAP protocols. Multiple
3343  attachment types can be declared for a SOAP service operation, i.e. adds
3344  definitions/binding/operation/input/MIME:multipartRelated/MIME:part/MIME:content/\@type
3345  for each type specified.
3346 
3347 -# To set the MIME type of a REST operation. This replaces XML declared in
3348  WSDL by definitions/binding/operation/(input|output)/MIME:mimeXml with
3349  MIME:content/\@type. Use `application/x-www-form-urlencoded` with REST POST
3350  and PUT protocols to send encoded form data automatically instead of XML.
3351  Only primitive type values can be transmitted with form data, such as
3352  numbers and strings, i.e. only types that are legal to use as
3353  [attributes members](#toxsd9-5).
3354 
3355 Use `method-input-mime-type` and `method-output-mime-type` to differentiate the
3356 attachment types between SOAP request and response messages.
3357 
3358 Schema directives {#directives-3}
3359 -----------------
3360 
3361 A schema directive is of the form:
3362 
3363 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3364  //gsoap <prefix> schema <property>: <value>
3365 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3366 
3367 where `<prefix>` is the XML namespace prefix of a schema. The `<property>` and
3368 `<value>` fields are one of the following:
3369 
3370 | Property | Value |
3371 | --------------- | --------------------------------------------------------------------------------- |
3372 | `namespace` | URI of the XSD targetNamespace |
3373 | `namespace2` | alternate URI for the XSD namespace (i.e. URI is also accepted by the XML parser) |
3374 | `import` | URI of imported namespace |
3375 | `form` | `unqualified` (default) or `qualified` local element and attribute form defaults |
3376 | `elementForm` | `unqualified` (default) or `qualified` local element form default |
3377 | `attributeForm` | `unqualified` (default) or `qualified` local attribute form default |
3378 | `typed` | `no` (default) or `yes` for serializers to add `xsi:type` attributes to XML |
3379 
3380 To learn more about the local form defaults, see [qualified and unqualified members.](#toxsd9-6)
3381 
3382 The `typed` property is implicitly `yes` when soapcpp2 option `-t` is used.
3383 
3384 Schema type directives {#directives-4}
3385 ----------------------
3386 
3387 A schema type directive is of the form:
3388 
3389 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3390  //gsoap <prefix> schema type-<property>: <name> <value>
3391  //gsoap <prefix> schema type-<property>: <name>::<member> <value>
3392 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3393 
3394 where `<prefix>` is the XML namespace prefix of a schema and `<name>` is an
3395 unqualified name of a C/C++ type, and the optional `<member>` is a class/struct
3396 members or enum constant.
3397 
3398 You can describe a type:
3399 
3400 | Type Property | Value |
3401 | -------------------- | ------------------------------- |
3402 | `type-documentation` | text describing the schema type |
3403 | `type` | same as above, shorthand form |
3404 
3405 For example, you can add a description to an enumeration:
3406 
3407 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3408  //gsoap ns schema type: Vowels The letters A, E, I, O, U, and sometimes Y
3409  //gsoap ns schema type: Vowels::Y A vowel, sometimes
3410  enum class ns__Vowels : char { A = 'A', E = 'E', I = 'I', O = 'O', U = 'U', Y = 'Y' };
3411 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3412 
3413 This documented enumeration maps to a simpleType restriction of `xsd:string` in
3414 the soapcpp2-generated schema:
3415 
3416  <simpleType name="Vowels">
3417  <annotation>
3418  <documentation>The letters A, E, I, O, U, and sometimes Y</documentation>
3419  </annotation>
3420  <restriction base="xsd:string">
3421  <enumeration value="A"/>
3422  <enumeration value="E"/>
3423  <enumeration value="I"/>
3424  <enumeration value="O"/>
3425  <enumeration value="U"/>
3426  <enumeration value="Y">
3427  <annotation>
3428  <documentation>A vowel, sometimes</documentation>
3429  </annotation>
3430  <enumeration/>
3431  </restriction>
3432  </simpleType>
3433 
3434 Serialization rules {#rules}
3435 ===================
3436 
3437 A presentation on XML data bindings is not complete without discussing the
3438 serialization rules and options that put your data in XML on the wire or store
3439 it a file or buffer.
3440 
3441 There are several options to choose from to serialize data in XML. The choice
3442 depends on the use of the SOAP protocol or if SOAP is not required. The wsdl2h
3443 tool automates this for you by taking the WSDL transport bindings into account
3444 when generating the service functions in C and C++ that use SOAP or REST.
3445 
3446 The gSOAP tools are not limited to SOAP. The tools implement generic XML data
3447 bindings for SOAP, REST, and other uses of XML. So you can read and write XML
3448 using the serializing [operations on classes and structs](#toxsd9-13).
3449 
3450 The following sections briefly explain the serialization rules with respect to
3451 the SOAP protocol for XML Web services. A basic understanding of the SOAP
3452 protocol is useful when developing client and server applications that must
3453 interoperate with other SOAP applications.
3454 
3455 SOAP/REST Web service client and service operations are represented as
3456 functions in your gSOAP header file with the data binding interface for
3457 soapcpp2. The soapcpp2 tool will translate these function to client-side
3458 service invocation calls and server-side service operation dispatchers.
3459 
3460 A discussion of SOAP clients and servers is beyond the scope of this document.
3461 However, the SOAP options discussed here also apply to SOAP client and server
3462 development.
3463 
3464 SOAP document versus rpc style {#doc-rpc}
3465 ------------------------------
3466 
3467 The `wsdl:binding/soap:binding/@style` attribute in the wsdl:binding section of
3468 a WSDL is either "document" or "rpc". The "rpc" style refers to SOAP RPC
3469 (Remote Procedure Call), which is more restrictive than the "document" style by
3470 requiring one XML element in the SOAP Body to act as the procedure name with
3471 XML subelements as its parameters.
3472 
3473 For example, the following directives in the gSOAP header file for soapcpp2
3474 declare that `DBupdate` is a SOAP RPC encoding service method:
3475 
3476 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3477  //gsoap ns service namespace: urn:DB
3478  //gsoap ns service method-protocol: DBupdate SOAP
3479  //gsoap ns service method-style: DBupdate rpc
3480  int ns__DBupdate(...);
3481 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3482 
3483 The XML payload has a SOAP envelope, optional SOAP header, and a SOAP body with
3484 one element representing the operation with the parameters as subelements:
3485 
3486  <SOAP-ENV:Envelope
3487  xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
3488  xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
3489  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
3490  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
3491  xmlsn:ns="urn:DB">
3492  <SOAP-ENV:Body>
3493  <ns:DBupdate>
3494  ...
3495  </ns:DBupdate>
3496  </SOAP-ENV:Body>
3497  </SOAP-ENV:Envelope>
3498 
3499 The "document" style puts no restrictions on the SOAP Body content. However, we
3500 recommend that the first element's tag name in the SOAP Body should be unique
3501 to each type of operation, so that the receiver can dispatch the operation
3502 based on this element's tag name. Alternatively, the HTTP URL path can be used
3503 to specify the operation, or the HTTP action header can be used to dispatch
3504 operations automatically on the server side (soapcpp2 options -a and -A).
3505 
3506 SOAP literal versus encoding {#lit-enc}
3507 ----------------------------
3508 
3509 The `wsdl:operation/soap:body/@use` attribute in the wsdl:binding section of a
3510 WSDL is either "literal" or "encoded". The "encoded" use refers to the SOAP
3511 encoding rules that support id-ref multi-referenced elements to serialize
3512 data as graphs.
3513 
3514 SOAP encoding is very useful if the data internally forms a graph (including
3515 cycles) and we want the graph to be serialized in XML in a format that ensures
3516 that its structure is preserved. In that case, SOAP 1.2 encoding is the best
3517 option.
3518 
3519 SOAP encoding also adds encoding rules for [SOAP arrays](#toxsd10) to serialize
3520 multi-dimensional arrays. The use of XML attributes to exchange XML data in
3521 SOAP encoding is not permitted. The only attributes permitted are the standard
3522 XSD attributes, SOAP encoding attributes (such as for arrays), and id-ref.
3523 
3524 For example, the following directives in the gSOAP header file for soapcpp2
3525 declare that `DBupdate` is a SOAP RPC encoding service method:
3526 
3527 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3528  //gsoap ns service namespace: urn:DB
3529  //gsoap ns service method-protocol: DBupdate SOAP
3530  //gsoap ns service method-style: DBupdate rpc
3531  //gsoap ns service method-encoding: DBupdate encoded
3532  int ns__DBupdate(...);
3533 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3534 
3535 The XML payload has a SOAP envelope, optional SOAP header, and a SOAP body with
3536 an encodingStyle attribute for SOAP 1.1 encoding and an element representing the
3537 operation with parameters that are SOAP 1.1 encoded:
3538 
3539  <SOAP-ENV:Envelope
3540  xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
3541  xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
3542  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
3543  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
3544  xmlsn:ns="urn:DB">
3545  <SOAP-ENV:Body SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
3546  <ns:DBupdate>
3547  <records SOAP-ENC:arrayType="ns:record[3]">
3548  <item>
3549  <name href="#_1"/>
3550  <SSN>1234567890</SSN>
3551  </item>
3552  <item>
3553  <name>Jane</name>
3554  <SSN>1987654320</SSN>
3555  </item>
3556  <item>
3557  <name href="#_1"/>
3558  <SSN>2345678901</SSN>
3559  </item>
3560  </records>
3561  </ns:DBupdate>
3562  <id id="_1" xsi:type="xsd:string">Joe</id>
3563  </SOAP-ENV:Body>
3564  </SOAP-ENV:Envelope>
3565 
3566 Note that the name "Joe" is shared by two records and the string is referenced
3567 by SOAP 1.1 href and id attributes.
3568 
3569 While gSOAP only introduces multi-referenced elements in the payload when they
3570 are actually multi-referenced in the data graph, other SOAP applications may
3571 render multi-referenced elements more aggressively. The example could also be
3572 rendered as:
3573 
3574  <SOAP-ENV:Envelope
3575  xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
3576  xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
3577  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
3578  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
3579  xmlsn:ns="urn:DB">
3580  <SOAP-ENV:Body SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
3581  <ns:DBupdate>
3582  <records SOAP-ENC:arrayType="ns:record[3]">
3583  <item href="#id1"/>
3584  <item href="#id2"/>
3585  <item href="#id3"/>
3586  </records>
3587  </ns:DBupdate>
3588  <id id="id1" xsi:type="ns:record">
3589  <name href="#id4"/>
3590  <SSN>1234567890</SSN>
3591  </id>
3592  <id id="id2" xsi:type="ns:record">
3593  <name href="#id5"/>
3594  <SSN>1987654320</SSN>
3595  </id>
3596  <id id="id3" xsi:type="ns:record">
3597  <name href="#id4"/>
3598  <SSN>2345678901</SSN>
3599  </id>
3600  <id id="id4" xsi:type="xsd:string">Joe</id>
3601  <id id="id5" xsi:type="xsd:string">Jane</id>
3602  </SOAP-ENV:Body>
3603  </SOAP-ENV:Envelope>
3604 
3605 SOAP 1.2 encoding is cleaner and produces more accurate XML encodings of data
3606 graphs by setting the id attribute on the element that is referenced:
3607 
3608  <SOAP-ENV:Envelope
3609  xmlns:SOAP-ENV="http://www.w3.org/2003/05/soap-envelope"
3610  xmlns:SOAP-ENC="http://www.w3.org/2003/05/soap-encoding"
3611  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
3612  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
3613  xmlsn:ns="urn:DB">
3614  <SOAP-ENV:Body>
3615  <ns:DBupdate SOAP-ENV:encodingStyle="http://www.w3.org/2003/05/soap-encoding">
3616  <records SOAP-ENC:itemType="ns:record" SOAP-ENC:arraySize="3">
3617  <item>
3618  <name SOAP-ENC:id="_1">Joe</name>
3619  <SSN>1234567890</SSN>
3620  </item>
3621  <item>
3622  <name>Jane</name>
3623  <SSN>1987654320</SSN>
3624  </item>
3625  <item>
3626  <name SOAP-ENC:ref="_1"/>
3627  <SSN>2345678901</SSN>
3628  </item>
3629  </records>
3630  </ns:DBupdate>
3631  </SOAP-ENV:Body>
3632  </SOAP-ENV:Envelope>
3633 
3634 @note Some SOAP 1.2 applications consider the namespace `SOAP-ENC` of
3635 `SOAP-ENC:id` and `SOAP-ENC:ref` optional. The gSOAP SOAP 1.2 encoding
3636 serialization follows the 2007 standard, while accepting unqualified id and
3637 ref attributes.
3638 
3639 To remove all rendered id-ref multi-referenced elements in gSOAP, use the
3640 `SOAP_XML_TREE` flag to initialize the gSOAP engine context.
3641 
3642 Some XML validation rules are turned off with SOAP encoding, because of the
3643 presence of additional attributes, such as id and ref/href, SOAP arrays with
3644 arbitrary element tags for array elements, and the occurrence of additional
3645 multi-ref elements in the SOAP 1.1 Body.
3646 
3647 The use of "literal" puts no restrictions on the XML in the SOAP Body. Full
3648 XML validation is possible, which can be enabled with the `SOAP_XML_STRICT`
3649 flag to initialize the gSOAP engine context. However, data graphs will be
3650 serialized as trees and cycles in the data will be cut from the XML rendition.
3651 
3652 SOAP 1.1 versus SOAP 1.2 {#soap}
3653 ------------------------
3654 
3655 There are two SOAP protocol versions: 1.1 and 1.2. The gSOAP tools can switch
3656 between the two versions seamlessly. You can declare the default SOAP version
3657 for a service operation as follows:
3658 
3659 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3660  //gsoap ns service method-protocol: DBupdate SOAP1.2
3661 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3662 
3663 The gSOAP soapcpp2 auto-generates client and server code. At the client side,
3664 this operation sends data with SOAP 1.2 but accepts responses also in SOAP 1.1.
3665 At the server side, this operation accepts requests in SOAP 1.1 and 1.2 and
3666 will return responses in the same SOAP version.
3667 
3668 As we discussed in the previous section, the SOAP 1.2 protocol has a cleaner
3669 multi-referenced element serialization format that greatly enhances the
3670 accuracy of data graph serialization with SOAP RPC encoding and is therefore
3671 recommended.
3672 
3673 The SOAP 1.2 protocol default can also be set by importing and loading
3674 `gsoap/import/soap12.h`:
3675 
3676 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3677  #import "soap12.h"
3678 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3679 
3680 Non-SOAP XML serialization {#non-soap}
3681 --------------------------
3682 
3683 You can serialize data that is stored on the heap, on the stack (locals), and
3684 static data as long as the serializable (i.e. non-transient) members are
3685 properly initialized and pointers in the structures are either NULL or point to
3686 valid structures. Deserialized data is put on the heap and managed by the
3687 gSOAP engine context `struct soap`, see also [memory management](#memory).
3688 
3689 You can read and write XML directly to a file or stream with the serializing
3690 [operations on classes and structs](#toxsd9-13).
3691 
3692 To define and use XML Web service client and service operations, we can declare
3693 these operations in your gSOAP header file with the data binding interface for
3694 soapcpp2 as functions. The function are translated by soapcpp2 to client-side
3695 service invocation calls and server-side service operation dispatchers.
3696 
3697 The REST operations POST, GET, and PUT are declared with `//gsoap` directives
3698 in the gSOAP header file for soapcpp2. For example, a REST POST operation is
3699 declared as follows:
3700 
3701 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3702  //gsoap ns service namespace: urn:DB
3703  //gsoap ns service method-protocol: DBupdate POST
3704  int ns__DBupdate(...);
3705 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3706 
3707 There is no SOAP Envelope and no SOAP Body in the payload for `DBupdate`. Also
3708 the XML serialization rules are identical to SOAP document/literal. The XML
3709 payload only has the operation name as an element with its parameters
3710 serialized as subelements:
3711 
3712  <ns:DBupdate xmln:ns="urn:DB" ...>
3713  ...
3714  </ns:DBupdate>
3715 
3716 To force id-ref serialization with REST similar to SOAP 1.2 multi-reference
3717 encoding, use the `SOAP_XML_GRAPH` flag to initialize the gSOAP engine context.
3718 The XML serialization includes id and ref attributes for multi-referenced
3719 elements as follows:
3720 
3721  <ns:DBupdate xmln:ns="urn:DB" ...>
3722  <records>
3723  <item>
3724  <name id="_1">Joe</name>
3725  <SSN>1234567890</SSN>
3726  </item>
3727  <item>
3728  <name>Jane</name>
3729  <SSN>1987654320</SSN>
3730  </item>
3731  <item>
3732  <name ref="_1"/>
3733  <SSN>2345678901</SSN>
3734  </item>
3735  </records>
3736  </ns:DBupdate>
3737 
3738 Input and output {#io}
3739 ================
3740 
3741 Reading and writing XML from/to files, streams and string buffers is done via
3742 the managing context by setting one of the following context members that
3743 control IO sources and sinks:
3744 
3745 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3746  soap->recvfd = fd; // an int file descriptor to read from (0 by default)
3747  soap->sendfd = fd; // an int file descriptor to write to (1 by default)
3748  soap->is = &is; // C++ only: a std::istream is object to read from
3749  soap->os = &os; // C++ only: a std::ostream os object to write to
3750  soap->is = cs; // C only: a const char* string to read from (soap->is will advance)
3751  soap->os = &cs; // C only: pointer to a const char*, will be set to point to the string output
3752 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3753 
3754 Normally, all of these context members are NULL, which is required to send and
3755 receive data over sockets by gSOAP clients and servers. Therefore, if you set
3756 any of these context members in a client or server application then you MUST
3757 reset them to NULL to ensure that socket communications are not blocked.
3758 
3759 Note: the use of `soap->is` and `soap->os` in C requires gSOAP 2.8.28 or later.
3760 
3761 In the following sections, we present more details on how to read and write to
3762 files and streams, and use string buffers as sources and sinks for XML data.
3763 
3764 In addition, you can set IO callback functions to handle IO at a lower level.
3765 
3766 For more details, see the [gSOAP user guide.](http://www.genivia.com/doc/soapdoc2.html)
3767 
3768 Reading and writing from/to files and streams {#io1}
3769 ---------------------------------------------
3770 
3771 The default IO is standard input and output. Other sources and sinks (those
3772 listed above) will be used until you (re)set them. For example with file-based
3773 input and output:
3774 
3775 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3776  FILE *fp = fopen("record.xml", "r");
3777  if (fp != NULL)
3778  {
3779  soap->recvfd = fileno(fp); // get file descriptor of file to read from
3780  if (soap_read_ns__record(soap, &pers1))
3781  ... // handle IO error
3782  fclose(fp);
3783  soap->recvfd = 0; // read from stdin, or -1 to block reading
3784  }
3785 
3786  FILE *fp = fopen("record.xml", "w");
3787  if (fp != NULL)
3788  {
3789  soap->sendfd = fileno(fp); // get file descriptor of file to write to
3790  if (soap_write_ns__record(soap, &pers1))
3791  ... // handle IO error
3792  fclose(fp);
3793  soap->sendfd = 1; // write to stdout, or -1 to block writing
3794  }
3795 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3796 
3797 Similar code with streams in C++:
3798 
3799 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3800  #include <fstream>
3801 
3802  std::fstream fs;
3803  fs.open("record.xml", std::ios::in);
3804  if (fs)
3805  {
3806  soap->is = &fs;
3807  if (soap_read__ns__record(soap, &pers1))
3808  ... // handle IO error
3809  fs.close();
3810  soap->is = NULL;
3811  }
3812 
3813  fs.open("record.xml", std::ios::out);
3814  if (fs)
3815  {
3816  soap->os = &fs;
3817  if (soap_write__ns__record(soap, &pers1))
3818  ... // handle IO error
3819  fs.close();
3820  soap->os = NULL;
3821  }
3822 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3823 
3824 Reading and writing from/to string buffers {#io2}
3825 ------------------------------------------
3826 
3827 For C++ we recommend to use `std::stringstream` objects from `<sstream>` as
3828 illustrated in the following example:
3829 
3830 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3831  #include <sstream>
3832 
3833  std::stringstream ss;
3834  ss.str("..."); // XML to parse
3835  soap->is = &ss;
3836  if (soap_read__ns__record(soap, &pers1))
3837  ... // handle IO error
3838  soap->is = NULL;
3839 
3840  soap->os = &ss;
3841  if (soap_write__ns__record(soap, &pers1))
3842  ... // handle IO error
3843  soap->os = NULL;
3844  std::string s = ss.str(); // string with XML
3845 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3846 
3847 For C we can use `soap->is` and `soap->os` to point to strings of XML content
3848 as follows (this requires gSOAP 2.8.28 or later):
3849 
3850 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3851  soap->is = "..."; // XML to parse
3852  if (soap_read__ns__record(soap, &pers1))
3853  ... // handle IO error
3854  soap->is = NULL;
3855 
3856  const char *cs = NULL;
3857  soap->os = &cs;
3858  if (soap_write__ns__record(soap, &pers1))
3859  ... // handle IO error
3860  soap->os = NULL;
3861  ... = cs; // string with XML (do not free(cs): managed by the context and freed with soap_end())
3862 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3863 
3864 Note that `soap->os` is a pointer to a `const char*` string. The pointer is
3865 set by the managing context to point to the XML data that is stored on the
3866 context-managed heap.
3867 
3868 For earlier gSOAP versions we recommend to use IO callbacks `soap->frecv` and
3869 `soap->fsend`, see the [gSOAP user guide.](http://www.genivia.com/doc/soapdoc2.html)
3870 
3871 Memory management {#memory}
3872 =================
3873 
3874 Memory management with the `soap` context enables us to allocate data in
3875 context-managed heap space that can be collectively deleted. All deserialized
3876 data is placed on the context-managed heap by the gSOAP engine.
3877 
3878 Memory management in C {#memory1}
3879 ----------------------
3880 
3881 When working with gSOAP in C (i.e. using wsdl2h option `-c` and soapcpp2 option
3882 `-c`), data is allocated on the managed heap with:
3883 
3884 - `void *soap_malloc(struct soap*, size_t len)`.
3885 
3886 You can also make shallow copies of data with `soap_memdup` that uses
3887 `soap_malloc` and a safe version of `memcpy` to copy a chunk of data `src` with
3888 length `len` to the context-managed heap:
3889 
3890 - `void * soap_memdup(struct soap*, const void *src, size_t len)`
3891 
3892 This function returns a pointer to the copy. This function requires gSOAP
3893 2.8.27 or later.
3894 
3895 In gSOAP 2.8.35 and later, you can use an auto-generated function to allocate
3896 and initialize data of type `T` on the managed heap:
3897 
3898 - `T * soap_new_T(struct soap*, int n)`
3899 
3900 This function returns an array of length `n` of type `T` data that is default
3901 initialized (by internally calling `soap_malloc(soap, n * sizeof(T))` and then
3902 `soap_default_T(soap, T*)` on each array value). Use `n=1` to allocate and
3903 initialize a single value.
3904 
3905 The `soap_malloc` function is a wrapper around `malloc`, but which also permits
3906 the `struct soap` context to track all heap allocations for collective deletion
3907 with `soap_end(soap)`:
3908 
3909 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3910  #include "soapH.h"
3911  #include "ns.nsmap"
3912  ...
3913  struct soap *soap = soap_new(); // new context
3914  ...
3915  struct ns__record *record = (struct ns__record*)soap_malloc(soap, sizeof(struct ns__record));
3916  soap_default_ns__record(soap, record); // auto-generated struct initializer
3917  ...
3918  soap_destroy(soap); // only for C++, see section on C++ below
3919  soap_end(soap); // delete record and all other heap allocations
3920  soap_free(soap); // delete context
3921 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3922 
3923 All data on the managed heap is mass-deleted with `soap_end(soap)` which must
3924 be called before `soap_done(soap)` or `soap_free(soap)` (these calls end the
3925 use of the `soap` engine context and free the context, respectively).
3926 
3927 The managed heap is checked for memory leaks when the gSOAP code is compiled
3928 with `-DDEBUG`.
3929 
3930 The soapcpp2 auto-generated deserializers in C use `soap_malloc` to allocate
3931 and populate deserialized structures, which are managed by the context for
3932 collective deletion.
3933 
3934 To make `char*` and `wchar_t*` string copies to the context-managed heap, we
3935 can use the functions:
3936 
3937 - `char *soap_strdup(struct soap*, const char *str)` and
3938 - `wchar_t *soap_wstrdup(struct soap*, const wchar_t *wstr)`.
3939 
3940 If your C compiler supports `typeof` then you can use the following macro to
3941 simplify the managed heap allocation and initialization of primitive values:
3942 
3943 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3944  #define soap_assign(soap, lhs, rhs) (*(lhs = (typeof(lhs))soap_malloc(soap, sizeof(*lhs))) = rhs)
3945 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3946 
3947 Pointers to primitive values are often used for optional members. For example,
3948 assume we have the following struct:
3949 
3950 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3951  struct ns__record
3952  {
3953  const char *name; // required name
3954  uint64_t *SSN; // optional SSN
3955  struct ns__record *spouse; // optional spouse
3956  };
3957 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3958 
3959 Use `soap_assign` to create a SSN value on the managed heap:
3960 
3961 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3962  struct soap *soap = soap_new(); // new context
3963  ...
3964  struct ns__record *record = (struct ns__record*)soap_malloc(soap, sizeof(struct ns__record));
3965  soap_default_ns__record(soap, record);
3966  record->name = soap_strdup(soap, "Joe");
3967  soap_assign(soap, record->SSN, 1234567890UL);
3968  ...
3969  soap_end(soap); // delete managed soap_malloc'ed heap data
3970  soap_free(soap); // delete context
3971 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3972 
3973 Without the `soap_assign` macro, you will need two lines of code, one to
3974 allocate and one to assign (you should also use this if your system can run out
3975 of memory):
3976 
3977 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3978  assert((record->SSN = (uint64_t*)soap_malloc(soap, sizeof(utint64_t))) != NULL);
3979  *record->SSN = 1234567890UL;
3980 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3981 
3982 The gSOAP serializer can serialize any heap, stack, or static allocated data.
3983 So we can also create a new record as follows:
3984 
3985 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
3986  struct soap *soap = soap_new(); // new context
3987  ...
3988  struct ns__record *record = (struct ns__record*)soap_malloc(soap, sizeof(struct ns__record));
3989  static uint64_t SSN = 1234567890UL;
3990  soap_default_ns__record(soap, record);
3991  record->name = "Joe";
3992  record->SSN = &SSN; // safe to use static values: the value of record->SSN is never changed by gSOAP
3993  ...
3994  soap_end(soap); // delete managed soap_malloc'ed heap data
3995  soap_free(soap); // delete context
3996 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3997 
3998 Use the soapcpp2 auto-generated `soap_dup_T` functions to duplicate data into
3999 another context (this requires soapcpp2 option `-Ec` to generate), here shown
4000 for C with the second argument `dst` NULL because we want to allocate a new
4001 managed structure:
4002 
4003 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4004  struct soap *other_soap = soap_new(); // another context
4005  struct ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
4006  ...
4007  soap_destroy(other_soap); // only for C++, see section on C++ below
4008  soap_end(other_soap); // delete other_record and all of its deep data
4009  soap_free(other_soap); // delete context
4010 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4011 
4012 Note that the only reason to use another context and not to use the primary
4013 context is when the primary context must be destroyed together with all of the
4014 objects it manages while some of the objects must be kept alive. If the objects
4015 that are kept alive contain deep cycles then this is the only option we have,
4016 because deep copy with a managing context detects and preserves these
4017 cycles unless the `SOAP_XML_TREE` flag is used with the context:
4018 
4019 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4020  struct soap *other_soap = soap_new1(SOAP_XML_TREE); // another context
4021  struct ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
4022 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4023 
4024 The resulting deep copy will be a full copy of the source data structure as a
4025 tree without co-referenced data (i.e. no digraph) and without cycles. Cycles
4026 are pruned and (one of the) pointers that forms a cycle is repaced by NULL.
4027 
4028 You can also deep copy into unmanaged space and use the auto-generated
4029 `soap_del_T()` function (requires soapcpp2 option `-Ed` to generate) to delete
4030 it later, but you MUST NOT do this for any data that has deep cycles in its
4031 runtime data structure:
4032 
4033 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4034  struct ns__record *other_record = soap_dup_ns__record(NULL, NULL, record);
4035  ...
4036  soap_del_ns__record(other_record); // deep delete record data members
4037  free(other_record); // delete the record
4038 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4039 
4040 Cycles in the data structure will lead to non-termination when making unmanaged
4041 deep copies. Consider for example:
4042 
4043 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4044  struct ns__record
4045  {
4046  const char *name; // required name
4047  uint64_t SSN; // required SSN
4048  struct ns__record *spouse; // optional spouse
4049  };
4050 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4051 
4052 The code to populate a structure with a mutual spouse relationship:
4053 
4054 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4055  struct soap *soap = soap_new();
4056  ...
4057  struct ns__record pers1, pers2;
4058  soap_default_ns__record(soap, &pers1);
4059  soap_default_ns__record(soap, &pers2);
4060  pers1.name = "Joe"; // OK to serialize static data
4061  pers1.SSN = 1234567890;
4062  pers1.spouse = &pers2;
4063  pers2.name = soap_strdup(soap, "Jane"); // allocates and copies a string
4064  pers2.SSN = 1987654320;
4065  pers2.spouse = &pers1;
4066  ...
4067  struct ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1); // BAD
4068  struct ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1); // OK
4069  soap_set_mode(soap, SOAP_XML_TREE);
4070  struct ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1); // OK
4071 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4072 
4073 As we can see, the gSOAP serializer can serialize any heap, stack, or static
4074 allocated data, such as in the code above. So we can serialize the
4075 stack-allocated `pers1` record as follows:
4076 
4077 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4078  FILE *fp = fopen("record.xml", "w");
4079  if (fp != NULL)
4080  {
4081  soap->sendfd = fileno(fp); // file descriptor to write to
4082  soap_set_mode(soap, SOAP_XML_GRAPH); // support id-ref w/o requiring SOAP
4083  soap_clr_mode(soap, SOAP_XML_TREE); // if set, clear
4084  soap_write_ns__record(soap, &pers1);
4085  fclose(fp);
4086  soap->sendfd = -1; // block further writing
4087  }
4088 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4089 
4090 which produces an XML document record.xml that is similar to:
4091 
4092  <ns:record xmlns:ns="urn:types" id="Joe">
4093  <name>Joe</name>
4094  <SSN>1234567890</SSN>
4095  <spouse id="Jane">
4096  <name>Jane</name>
4097  <SSN>1987654320</SSN>
4098  <spouse ref="#Joe"/>
4099  </spouse>
4100  </ns:record>
4101 
4102 Deserialization of an XML document with a SOAP 1.1/1.2 encoded id-ref graph
4103 leads to the same non-termination problem when we later try to copy the data
4104 into unmanaged memory heap space:
4105 
4106 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4107  struct soap *soap = soap_new1(SOAP_XML_GRAPH); // support id-ref w/o SOAP
4108  ...
4109  struct ns__record pers1;
4110  FILE *fp = fopen("record.xml", "r");
4111  if (fp != NULL)
4112  {
4113  soap->recvfd = fileno(fp);
4114  if (soap_read_ns__record(soap, &pers1))
4115  ... // handle IO error
4116  fclose(fp);
4117  soap->recvfd = -1; // blocks further reading
4118  }
4119  ...
4120  struct ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1); // BAD
4121  struct ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1); // OK
4122  soap_set_mode(soap, SOAP_XML_TREE);
4123  struct ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1); // OK
4124 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4125 
4126 Copying data with `soap_dup_T(soap)` into managed heap memory space is always
4127 safe. Copying into unmanaged heap memory space requires diligence. But
4128 deleting unmanaged data is easy with `soap_del_T()`.
4129 
4130 You can also use `soap_del_T()` to delete structures that you created in C, but
4131 only if these structures are created with `malloc` and do NOT contain pointers
4132 to stack and static data.
4133 
4134 Finally, when data is allocated in managed memory heap space, either explicitly
4135 with the allocation functions shown above or by the gSOAP deserializers, you
4136 can delegate the management and deletion of this data to another `struct soap`
4137 context. That context will be responsible to delete the data with
4138 `soap_end(soap)` later:
4139 
4140 - `void delegate_deletion(struct soap *soap_from, struct soap *soap_to)`
4141 
4142 This allows the `soap_from` context to be deleted with `soap_free(soap_from)`
4143 (assuming it is allocated with `soap_new()`, use `soap_done(soap_from)` when
4144 `soap_from` is stack-allocated) while the managed data remains intact. You
4145 can use this function any time, to delegate management and deletion to another
4146 context `soap_to` and then continue with the current context. You can also use
4147 different source `soap_from` contexts to delegate management and deletion to
4148 the other `soap_to` context. To mass delete all managed data, use
4149 `soap_end(soap_to)`.
4150 
4151 Memory management in C++ {#memory2}
4152 ------------------------
4153 
4154 When working with gSOAP in C++, the gSOAP engine allocates data on a managed
4155 heap using `soap_new_T(soap)` to allocate a type with type name `T`. Managed
4156 heap allocation is tracked by the `struct soap` context for collective deletion
4157 with `soap_destroy(soap)` for structs, classes, and templates and with
4158 `soap_end(soap)` for everything else.
4159 
4160 You should only use `soap_malloc(struct soap*, size_t len)` to allocate
4161 primitive types, but `soap_new_T()` is preferred. The auto-generated `T *
4162 soap_new_T(struct soap*)` returns data allocated on the managed heap for type
4163 `T`. The data is mass-deleted with `soap_destroy(soap)` followed by
4164 `soap_end(soap)`.
4165 
4166 There are four variations of `soap_new_T()` to allocate data of type `T` that
4167 soapcpp2 auto-generates:
4168 
4169 - `T * soap_new_T(struct soap*)` returns a new instance of `T` that is default
4170  initialized. For classes, initialization is internally performed using the
4171  soapcpp2 auto-generated `void T::soap_default(struct soap*)` method of the
4172  class, but ONLY IF the soapcpp2 auto-generated default constructor is used
4173  that invokes `soap_default()` and was not replaced by a user-defined default
4174  constructor.
4175 
4176 - `T * soap_new_T(struct soap*, int n)` returns an array of `n` new instances of
4177  `T`. The instances in the array are default initialized as described above.
4178 
4179 - `T * soap_new_req_T(struct soap*, ...)` (structs and classes only) returns a
4180  new instance of `T` and sets the required data members to the values
4181  specified in `...`. The required data members are those with nonzero
4182  minOccurs, see the subsections on
4183  [(smart) pointer members and their occurrence constraints](#toxsd9-8) and
4184  [container and array members and their occurrence constraints](#toxsd9-9).
4185 
4186 - `T * soap_new_set_T(struct soap*, ...)` (structs and classes only) returns a
4187  new instance of `T` and sets the public/serializable data members to the values
4188  specified in `...`.
4189 
4190 The above functions can be invoked with a NULL `soap` context, but you are then
4191 responsible to use `delete T` to remove this instance from the unmanaged heap.
4192 
4193 For example, to allocate a managed `std::string` you can use:
4194 
4195 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4196  std::string *s = soap_new_std__string(soap);
4197 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4198 
4199 Primitive types and arrays of these are allocated with `soap_malloc`
4200 (`soap_new_T` calls `soap_malloc` for primitive type `T`). All primitive types
4201 (i.e. no classes, structs, class templates, containers, and smart pointers) are
4202 allocated with `soap_malloc` for reasons of efficiency.
4203 
4204 You can use a C++ template to simplify the managed allocation and initialization
4205 of primitive values as follows (this is for primitive types only):
4206 
4207 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4208  template<class T>
4209  T * soap_make(struct soap *soap, T val)
4210  {
4211  T *p = (T*)soap_malloc(soap, sizeof(T));
4212  if (p) // out of memory? Can also guard with assert(p != NULL) or throw an error
4213  *p = val;
4214  return p;
4215  }
4216 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4217 
4218 For example, assuming we have the following class:
4219 
4220 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4221  class ns__record
4222  {
4223  public:
4224  std::string name; // required name
4225  uint64_t *SSN; // optional SSN
4226  ns__record *spouse; // optional spouse
4227  };
4228 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4229 
4230 You can instantiate a record by using the auto-generated
4231 `soap_new_set_ns__record` and use `soap_make` to create a SSN value on the
4232 managed heap as follows:
4233 
4234 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4235  soap *soap = soap_new(); // new context
4236  ...
4237  ns__record *record = soap_new_set_ns__record(
4238  soap,
4239  "Joe",
4240  soap_make<uint64_t>(soap, 1234567890UL),
4241  NULL);
4242  ...
4243  soap_destroy(soap); // delete record and all other managed instances
4244  soap_end(soap); // delete managed soap_malloc'ed heap data
4245  soap_free(soap); // delete context
4246 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4247 
4248 All data on the managed heap is mass-deleted with `soap_destroy(soap)` and
4249 `soap_end(soap)` which must be called before `soap_done(soap)` or
4250 `soap_free(soap)` (these calls end the use of the `soap` engine context and
4251 free the context, respectively).
4252 
4253 The managed heap is checked for memory leaks when the gSOAP code is compiled
4254 with `-DDEBUG`.
4255 
4256 Note however that the gSOAP serializer can serialize any heap, stack, or static
4257 allocated data. So we can also create a new record as follows:
4258 
4259 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4260  uint64_t SSN = 1234567890UL;
4261  ns__record *record = soap_new_set_ns__record(soap, "Joe", &SSN, NULL);
4262 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4263 
4264 which will be fine to serialize this record as long as the local `SSN`
4265 stack-allocated value remains in scope when invoking the serializer and/or
4266 using `record`. It does not matter if `soap_destroy` and `soap_end` are called
4267 beyond the scope of `SSN`.
4268 
4269 To facilitate class methods to access the managing context, we can add a soap
4270 context pointer to a class/struct:
4271 
4272 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4273  class ns__record
4274  {
4275  ...
4276  void create_more(); // needs a context to create more internal data
4277  protected:
4278  struct soap *soap; // the context that manages this instance, or NULL
4279  };
4280 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4281 
4282 The context is set when invoking `soap_new_T` (and similar) with a non-NULL
4283 context argument.
4284 
4285 You can also use a template when an array of pointers to values is required.
4286 To create an array of pointers to values, define the following template:
4287 
4288 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4289  template<class T>
4290  T **soap_make_array(struct soap *soap, T* array, int n)
4291  {
4292  T **p = (T**)soap_malloc(soap, n * sizeof(T*));
4293  for (int i = 0; i < n; ++i)
4294  p[i] = &array[i];
4295  return p;
4296  }
4297 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4298 
4299 The `array` parameter is a pointer to an array of `n` values. The template
4300 returns an array of `n` pointers that point to the values in that array:
4301 
4302 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4303  // create an array of 100 pointers to 100 records
4304  int n = 100;
4305  ns__record **precords = soap_make_array(soap, soap_new_ns__record(soap, n), n);
4306  for (int i = 0; i < n; ++i)
4307  {
4308  precords[i]->name = "...";
4309  precords[i]->SSN = soap_make<uint64_t>(1234567890UL + i);
4310  }
4311 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4312 
4313 Note that `soap_new_ns__record(soap, n)` returns a pointer to an array of `n`
4314 records, which is then used to create an array of `n` pointers to these records.
4315 
4316 Use the soapcpp2 auto-generated `soap_dup_T` functions to duplicate data into
4317 another context (this requires soapcpp2 option `-Ec` to generate), here shown
4318 for C++ with the second argument `dst` NULL to allocate a new managed object:
4319 
4320 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4321  soap *other_soap = soap_new(); // another context
4322  ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
4323  ...
4324  soap_destroy(other_soap); // delete record and other managed instances
4325  soap_end(other_soap); // delete other data (the SSNs on the heap)
4326  soap_free(other_soap); // delete context
4327 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4328 
4329 To duplicate base and derived instances when a base class pointer or reference
4330 is provided, use the auto-generated method `T * T::soap_dup(struct soap*)`:
4331 
4332 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4333  soap *other_soap = soap_new(); // another context
4334  ns__record *other_record = record->soap_dup(other_soap);
4335  ...
4336  soap_destroy(other_soap); // delete record and other managed instances
4337  soap_end(other_soap); // delete other data (the SSNs on the heap)
4338  soap_free(other_soap); // delete context
4339 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4340 
4341 Note that the only reason to use another context and not to use the primary
4342 context is when the primary context must be destroyed together with all of the
4343 objects it manages while some of the objects must be kept alive. If the objects
4344 that are kept alive contain deep cycles then this is the only option we have,
4345 because deep copy with a managing context detects and preserves these
4346 cycles unless the `SOAP_XML_TREE` flag is used with the context:
4347 
4348 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4349  soap *other_soap = soap_new1(SOAP_XML_TREE); // another context
4350  ns__record *other_record = record->soap_dup(other_soap); // deep tree copy
4351 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4352 
4353 The resulting deep copy will be a full copy of the source data structure as a
4354 tree without co-referenced data (i.e. no digraph) and without cycles. Cycles
4355 are pruned and (one of the) pointers that forms a cycle is repaced by NULL.
4356 
4357 You can also deep copy into unmanaged space and use the auto-generated
4358 `soap_del_T()` function or the `T::soap_del()` method (requires soapcpp2 option
4359 `-Ed` to generate) to delete it later, but we MUST NOT do this for any data
4360 that has deep cycles in its runtime data structure graph:
4361 
4362 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4363  ns__record *other_record = record->soap_dup(NULL);
4364  ...
4365  other_record->soap_del(); // deep delete record data members
4366  delete other_record; // delete the record
4367 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4368 
4369 Cycles in the data structure will lead to non-termination when making unmanaged
4370 deep copies. Consider for example:
4371 
4372 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4373  class ns__record
4374  {
4375  const char *name; // required name
4376  uint64_t SSN; // required SSN
4377  ns__record *spouse; // optional spouse
4378  };
4379 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4380 
4381 The code to populate a structure with a mutual spouse relationship:
4382 
4383 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4384  soap *soap = soap_new();
4385  ...
4386  ns__record pers1, pers2;
4387  pers1.name = "Joe";
4388  pers1.SSN = 1234567890;
4389  pers1.spouse = &pers2;
4390  pers2.name = "Jane";
4391  pers2.SSN = 1987654320;
4392  pers2.spouse = &pers1;
4393  ...
4394  ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1); // BAD
4395  ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1); // OK
4396  soap_set_mode(soap, SOAP_XML_TREE);
4397  ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1); // OK
4398 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4399 
4400 Note that the gSOAP serializer can serialize any heap, stack, or static
4401 allocated data, such as in the code above. So we can serialize the
4402 stack-allocated `pers1` record as follows:
4403 
4404 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4405  FILE *fp = fopen("record.xml", "w");
4406  if (fp != NULL)
4407  {
4408  soap->sendfd = fileno(fp); // file descriptor to write to
4409  soap_set_mode(soap, SOAP_XML_GRAPH); // support id-ref w/o requiring SOAP
4410  soap_clr_mode(soap, SOAP_XML_TREE); // if set, clear
4411  if (soap_write_ns__record(soap, &pers1))
4412  ... // handle IO error
4413  fclose(fp);
4414  soap->sendfd = -1; // block further writing
4415  }
4416 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4417 
4418 which produces an XML document record.xml that is similar to:
4419 
4420  <ns:record xmlns:ns="urn:types" id="Joe">
4421  <name>Joe</name>
4422  <SSN>1234567890</SSN>
4423  <spouse id="Jane">
4424  <name>Jane</name>
4425  <SSN>1987654320</SSN>
4426  <spouse ref="#Joe"/>
4427  </spouse>
4428  </ns:record>
4429 
4430 Deserialization of an XML document with a SOAP 1.1/1.2 encoded id-ref graph
4431 leads to the same non-termination problem when we later try to copy the data
4432 into unmanaged space:
4433 
4434 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4435  soap *soap = soap_new1(SOAP_XML_GRAPH); // support id-ref w/o SOAP
4436  ...
4437  ns__record pers1;
4438  FILE *fp = fopen("record.xml", "r");
4439  if (fp != NULL)
4440  {
4441  soap->recvfd = fileno(fp); // file descriptor to read from
4442  if (soap_read_ns__record(soap, &pers1))
4443  ... // handle IO error
4444  fclose(fp);
4445  soap->recvfd = -1; // block further reading
4446  }
4447  ...
4448  ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1); // BAD
4449  ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1); // OK
4450  soap_set_mode(soap, SOAP_XML_TREE);
4451  ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1); // OK
4452 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4453 
4454 Copying data with `soap_dup_T(soap)` into managed space is always safe. Copying
4455 into unmanaged space requires diligence. But deleting unmanaged data is easy
4456 with `soap_del_T()`.
4457 
4458 You can also use `soap_del_T()` to delete structures in C++, but only if these
4459 structures are created with `new` (and `new []` for arrays when applicable) for
4460 classes, structs, and class templates and with `malloc` for anything else, and
4461 the structures do NOT contain pointers to stack and static data.
4462 
4463 Finally, when data is allocated in managed memory heap space, either explicitly
4464 with the allocation functions shown above or by the gSOAP deserializers, you
4465 can delegate the management and deletion of this data to another `struct soap`
4466 context. That context will be responsible to delete the data with
4467 `soap_destroy(soap)` and `soap_end(soap)` later:
4468 
4469 - `void delegate_deletion(struct soap *soap_from, struct soap *soap_to)`
4470 
4471 This allows the `soap_from` context to be deleted with `soap_free(soap_from)`
4472 (assuming it is allocated with `soap_new()`, use `soap_done(soap_from)` when
4473 `soap_from` is stack-allocated) while the managed data remains intact. You
4474 can use this function any time, to delegate management and deletion to another
4475 context `soap_to` and then continue with the current context. You can also use
4476 different source `soap_from` contexts to delegate management and deletion to
4477 the other `soap_to` context. To mass delete all managed data, use
4478 `soap_destroy(soap_to)` followed by `soap_end(soap_to)`.
4479 
4480 Context flags to initialize the soap struct {#flags}
4481 ===========================================
4482 
4483 There are several context initialization flags and context mode flags to
4484 control XML serialization at runtime. The flags are set with `soap_new1()` to
4485 allocate and initialize a new context:
4486 
4487 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4488  struct soap *soap = soap_new1(<flag> | <flag> ... | <flag>);
4489  ,,,
4490  soap_destroy(soap); // delete objects
4491  soap_end(soap); // delete other data and temp data
4492  soap_free(soap); // free context
4493 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4494 
4495 and with `soap_init1()` for stack-allocated contexts:
4496 
4497 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4498  struct soap soap;
4499  soap_init1(&soap, <flag> | <flag> ... | <flag>);
4500  ,,,
4501  soap_destroy(&soap); // delete objects
4502  soap_end(&soap); // delete other data and temp data
4503  soap_done(&soap); // clear context
4504 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4505 
4506 where `<flag>` is one of:
4507 
4508 - `SOAP_C_UTFSTRING`: enables all `std::string` and `char*` strings to
4509  contain UTF-8 content. This option is recommended.
4510 
4511 - `SOAP_C_NILSTRING`: treat empty strings as if they were NULL pointers, i.e.
4512  omits elements and attributes when empty.
4513 
4514 - `SOAP_XML_STRICT`: strictly validates XML while deserializing. Should not be
4515  used together with SOAP 1.1/1.2 encoding style of messaging. Use soapcpp2
4516  option `-s` to hard code `SOAP_XML_STRICT` in the generated serializers. Not
4517  recommended with SOAP 1.1/1.2 encoding style messaging.
4518 
4519 - `SOAP_XML_INDENT`: produces indented XML.
4520 
4521 - `SOAP_XML_CANONICAL`: c14n canonocalization, removes unused `xmlns` bindings
4522  and adds them to appropriate places by applying c14n normalization rules.
4523  Should not be used together with SOAP 1.1/1.2 encoding style messaging.
4524 
4525 - `SOAP_XML_TREE`: write tree XML without id-ref, while pruning data structure
4526  cycles to prevent nontermination of the serializer for cyclic structures.
4527 
4528 - `SOAP_XML_GRAPH`: write graph (digraph and cyclic graphs with shared pointers
4529  to objects) using id-ref attributes. That is, XML with SOAP multi-ref
4530  encoded id-ref elements. This is a structure-preserving serialization format,
4531  because co-referenced data and also cyclic relations are accurately represented.
4532 
4533 - `SOAP_XML_DEFAULTNS`: uses xmlns default namespace declarations, assuming
4534  that the schema attribute form is "qualified" by default (be warned if it is
4535  not, since attributes in the null namespace will get bound to namespaces!).
4536 
4537 - `SOAP_XML_NIL`: emit empty element with `xsi:nil` for all NULL pointers
4538  serialized.
4539 
4540 - `SOAP_XML_IGNORENS`: the XML parser ignores XML namespaces, i.e. element and
4541  attribute tag names match independent of their namespace.
4542 
4543 - `SOAP_XML_NOTYPE`: removes all `xsi:type` attribuation. This option is usually
4544  not needed unless the receiver rejects all `xsi:type` attributes. This option
4545  may affect the quality of the deserializer, which relies on `xsi:type`
4546  attributes to distinguish base class instances from derived class instances
4547  transported in the XML payloads.
4548 
4549 - `SOAP_IO_CHUNK`: to enable HTTP chunked transfers.
4550 
4551 - `SOAP_IO_STORE`: full buffering of outbound messages.
4552 
4553 - `SOAP_ENC_ZLIB`: compress messages, requires compiling with `-DWITH_GZIP` and
4554  linking with zlib (`-lz`).
4555 
4556 - `SOAP_ENC_MIME`: enable MIME attachments, see
4557  [MIME/MTOM attachment binary types](#toxsd10-3).
4558 
4559 - `SOAP_ENC_MTOM`: enable MTOM attachments, see
4560  [MIME/MTOM attachment binary types](#toxsd10-3).
4561 
4562 @note C++ Web service proxy and service classes have their own context, either
4563 as a base class (soapcpp2 option -i) or as a data member `soap` that points to
4564 a context (soapcpp2 option -j). These contexts are allocated when the proxy or
4565 service is instantiated with context flags that are passed to the constructor.
4566 
4567 Context parameter settings {#params}
4568 ==========================
4569 
4570 After allocation and initializtion of a `struct soap` context, several context
4571 parameters can be set (some parameters may require 2.8.31 and later versions):
4572 
4573 - `unsigned int soap::maxlevel` is the maximum XML nesting depth levels that
4574  the parser permits. Default initialized to `SOAP_MAXLEVEL` (10000), which is
4575  a redefinable macro in stdsoap2.h. Set `soap::maxlevel` to a lower value to
4576  restrict XML parsing nesting depth.
4577 
4578 - `long soap::maxlength` is the maximum string content length if not already
4579  constrained by an XML schema validation `maxLength` constraint. Zero means
4580  unlimited string lengths are permitted (unless restricted by XML schema
4581  `maxLength`). Default initialized to `SOAP_MAXLENGTH` (0), which is a
4582  redefinable macro in stdsoap2.h. Set `soap::maxlength` to a positive value
4583  to restrict the number of (wide) characters in strings parsed, restrict
4584  hexBinary byte length, and restrict base64Binary byte length.
4585 
4586 - `size_t soap::maxoccurs` is the maximum number of array or container elements
4587  permitted by the parser. Must be greater than zero (0). Default initialized
4588  to `SOAP_MAXOCCURS` (100000), which is a redefinable macro in stdsoap2.h.
4589  Set `soap::maxoccurs` to a positive value to restrict the number of array and
4590  container elements that can be parsed.
4591 
4592 - `soap::version` is the SOAP version used, with 0 for non-SOAP, 1 for SOAP1.1,
4593  and 2 for SOAP1.2. This value is normally set by web service operations, and
4594  is otherwise 0 (non-SOAP). Use `soap_set_version(struct soap*, short)` to
4595  set the value. This controls XML namespaces and SOAP id-ref serialization
4596  when applicable with an encodingStyle (see below).
4597 
4598 - `const char *soap::encodingStyle` is a string that is used with SOAP
4599  encoding, normally NULL for non-SOAP XML. Set this string to "" (empty
4600  string) to enable SOAP encoding style, which supports id-ref graph
4601  serialization (see also the `SOAP_XML_GRAPH` [context flag](#flags)).
4602 
4603 - `int soap::recvfd` is the file descriptor to read and parse source data from.
4604  Default initialized to 0 (stdin). See also [input and output](#io).
4605 
4606 - `int soap::sendfd` is the file descriptor to write data to. Default
4607  initialized to 1 (stdout). See also [input and output](#io).
4608 
4609 - `const char *is` for C: string to read and parse source data from, overriding
4610  the `recvfd` source. Normally NULL. This value must be reset to NULL or
4611  the parser will continue to read from this string content until the NUL
4612  character. See also [input and output](#io).
4613 
4614 - `std::istream *is` for C++: an input stream to read and parse source data
4615  from, overriding the `recvfd` source. Normally NULL. This value must be
4616  reset to NULL or the parser will continue to read from this stream until EOF.
4617  See also [input and output](#io).
4618 
4619 - `const char **os` for C: points to a string (a `const char *`) that will be
4620  set to point to the string output. Normally NULL. This value must be reset
4621  to NULL or the next output will result in reassigning the pointer to point to
4622  the next string that is output. The strings are automatically deallocated by
4623  `soap_end(soap)`. See also [input and output](#io).
4624 
4625 - `std::ostream *os` for C++: an output stream to write output to. Normally
4626  NULL. This value must be reste to NULL or the next output will be send to
4627  this stream. See also [input and output](#io).
4628 
4629 Error handling and reporting {#errors}
4630 ==========================
4631 
4632 The gSOAP API functions return `SOAP_OK` (zero) or a non-zero error code. The
4633 error code is stored in `int soap::error` of the current `struct soap` context.
4634 Error messages can be displayed with:
4635 
4636 - `void soap_stream_fault(struct soap*, std::ostream &os)` for C++ only, prints
4637  the error message to an output stream.
4638 
4639 - `void soap_print_fault(struct soap*, FILE *fd)` prints the error message to a
4640  FILE descriptor.
4641 
4642 - `void soap_sprint_fault(struct soap*, char *buf, size_t len)` saves the error
4643  message to a fixed-size buffer allocated with a maximum length.
4644 
4645 - `void soap_print_fault_location(struct soap*, FILE *fd)` prints the location
4646  and part of the XML where the parser encountered an error.
4647 
4648 An EOF (`SOAP_EOF` or -1) error code is returned when the parser has hit EOF
4649 but expected more input.
4650 
4651 A `SOAP_EOM` error code is returned when memory was exhausted during
4652 processing of input and/or output of data.
4653 
4654 Use `soap_xml_error_check(soap->error)` to check for XML errors. This returns
4655 true (non-zero) when a parsing and validation error has occurred.
4656 
4657 For example:
4658 
4659 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4660  #include <sstream>
4661 
4662  struct soap *soap = soap_new1(SOAP_XML_INDENT | SOAP_XML_STRICT | SOAP_XML_TREE);
4663  struct ns__record person;
4664  std::stringstream ss;
4665  ss.str("..."); // XML to parse
4666  soap->is = &ss;
4667  if (soap_read__ns__record(soap, &person))
4668  {
4669  if (soap_xml_error_check(soap->error))
4670  std::cerr << "XML parsing error!" << std::endl;
4671  else
4672  soap_stream_fault(soap, std::cerr);
4673  }
4674  else
4675  {
4676  ... // all OK, use person record
4677  }
4678  soap_destroy(soap); // delete objects
4679  soap_end(soap); // delete other data and temp data
4680  soap_free(soap); // free context
4681 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4682 
4683 Features and limitations {#features}
4684 ========================
4685 
4686 In general, to use the generated code:
4687 
4688 - Make sure to `#include "soapH.h"` in your code and also define a namespace
4689  table or `#include "ns.nsmap"` with the generated table, where `ns` is the
4690  namespace prefix for services.
4691 
4692 - Use soapcpp2 option -j (C++ only) to generate C++ proxy and service objects.
4693  The auto-generated files include documented inferfaces. Compile with
4694  soapC.cpp and link with -lgsoap++, or alternatively compile stdsoap2.cpp.
4695 
4696 - Without soapcpp2 option -j: client-side uses the auto-generated
4697  soapClient.cpp and soapC.cpp (or C versions of those). Compile and link with
4698  -lgsoap++ (-lgsoap for C), or alternatively compile stdsoap2.cpp
4699  (stdsoap2.c for C).
4700 
4701 - Without soapcpp2 option -j: server-side uses the auto-generated
4702  soapServer.cpp and soapC.cpp (or C versions of those). Compile and link with
4703  -lgsoap++ (-lgsoap for C), or alternatively compile stdsoap2.cpp (stdsoap2.c
4704  for C).
4705 
4706 - Use `soap_new()` or `soap_new1(int flags)` to allocate and initialize a
4707  heap-allocated context with or without flags. Delete this context with
4708  `soap_free(struct soap*)`, but only after `soap_destroy(struct soap*)` and
4709  `soap_end(struct soap*)`.
4710 
4711 - Use `soap_init(struct *soap)` or `soap_init1(struct soap*, int flags)` to
4712  initialize a stack-allocated context with or without flags. End the use of
4713  this context with `soap_done(struct soap*)`, but only after
4714  `soap_destroy(struct soap*)` and `soap_end(struct soap*)`.
4715 
4716 Additional notes with respect to the wsdl2h and soapcpp2 tools:
4717 
4718 - Nested classes, structs, and unions in a gSOAP header file are unnested by
4719  soapcpp2.
4720 
4721 - Use `#import "file.h"` instead of `#include` to import other header files in
4722  a gSOAP header file for soapcpp2. The `#include`, `#define`, and `#pragma`
4723  are accepted by soapcpp2, but are moved to the very start of the generated
4724  code for the C/C++ compiler to include before all generated definitions.
4725  Often it is useful to add an `#include` with a [volatile type](#toxsd9-2)
4726  that includes the actual type declaration, and to ensure transient types are
4727  declared when these are used in a data binding interface declared in a gSOAP
4728  header file for soapcpp2.
4729 
4730 - To remove any SOAP-specific bindings, use soapcpp2 option `-0`.
4731 
4732 - A gSOAP header file for soapcpp2 should not include any code statements, only
4733  data type declarations. This includes constructor initialization lists that are
4734  not permitted. Use member initializations instead.
4735 
4736 - C++ namespaces are supported. Use wsdl2h option `-qname`. Or add a `namespace
4737  name { ... }` to the header file, but the `{ ... }` MUST cover the entire
4738  header file content from begin to end.
4739 
4740 - Optional XML DOM support can be used to store mixed content or literal XML
4741  content. Otherwise, mixed content may be lost. Use wsdl2h option `-d` for
4742  XML DOM support and compile and link with `dom.c` or `dom.cpp`. For details,
4743  see [XML DOM and XPath](http://www.genivia.com/doc/dom/html).
4744 
4745 Removing SOAP namespaces from XML payloads {#nsmap}
4746 ==========================================
4747 
4748 The soapcpp2 tool generates a `.nsmap` file that includes two bindings for SOAP
4749 namespaces. We can remove all SOAP namespaces (and SOAP processing logic) with
4750 soapcpp2 option `-0` or by simply setting the two entries to NULL:
4751 
4752 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4753  struct Namespace namespaces[] =
4754  {
4755  {"SOAP-ENV", NULL, NULL, NULL},
4756  {"SOAP-ENC", NULL, NULL, NULL},
4757  ...
4758  };
4759 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4760 
4761 Note that once the `.nsmap` is generated, you can copy-paste the content into
4762 your project code. However, if we rerun wsdl2h on updated WSDL/XSD files or
4763 `typemap.dat` declarations then we need to use the updated table.
4764 
4765 In cases that no XML namespaces are used at all, for example with
4766 [XML-RPC](http://www.genivia.com/doc/xml-rpc-json/html), you may use an empty
4767 namespace table:
4768 
4769 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
4770  struct Namespace namespaces[] = {{NULL,NULL,NULL,NULL}};
4771 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4772 
4773 However, beware that any built-in xsi attributes that are rendered will lack
4774 the proper namespace binding. At least we suggest to use `SOAP_XML_NOTYPE` for
4775 this reason.
4776 
4777 Examples {#examples}
4778 ========
4779 
4780 Select the project files below to peruse the source code examples.
4781 
4782 Source files
4783 ------------
4784 
4785 - `address.xsd` Address book schema
4786 - `address.cpp` Address book app (reads/writes address.xml file)
4787 - `addresstypemap.dat` Schema namespace prefix name preference for wsdl2h
4788 - `graph.h` Graph data binding (tree, digraph, cyclic graph)
4789 - `graph.cpp` Test graph serialization as tree, digraph, and cyclic
4790 
4791 Generated files
4792 ---------------
4793 
4794 - `address.h` gSOAP-specific data binding definitions from address.xsd
4795 - `addressStub.h` C++ data binding definitions
4796 - `addressH.h` Serializers
4797 - `addressC.cpp` Serializers
4798 - `address.xml` Address book data generated by address app
4799 - `graphStub.h` C++ data binding definitions
4800 - `graphH.h` Serializers
4801 - `graphC.cpp` Serializers
4802 - `g.xsd` XSD schema with `g:Graph` complexType
4803 - `g.nsmap` xmlns bindings namespace mapping table
4804 
4805 Build steps
4806 -----------
4807 
4808 Building the AddressBook example:
4809 
4810  wsdl2h -g -t addresstypemap.dat address.xsd
4811  soapcpp2 -0 -CS -I../../import -p address address.h
4812  c++ -I../.. address.cpp addressC.cpp -o address -lgsoap++
4813 
4814 Option `-g` produces bindings for global (root) elements in addition to types.
4815 In this case the root element `a:address-book` is bound to `_a__address_book`.
4816 The complexType `a:address` is bound to class `a__address`, which is also the
4817 type of `_a__address_book`. This option is not required, but allows you to use
4818 global element tag names when referring to their serializers, instead of their
4819 type name. Option `-0` removes the SOAP protocol. Options `-C` and `-S`
4820 removes client and server code generation. Option `-p` renames the output
4821 `soap` files to `address` files.
4822 
4823 See the `address.cpp` implementation and [related pages](pages.html).
4824 
4825 The `addresstypemap.dat` file specifies the XML namespace prefix for the
4826 bindings:
4827 
4828  # Bind the address book schema namespace to prefix 'a'
4829 
4830  a = "urn:address-book-example"
4831 
4832  # By default the xsd:dateTime schema type is translated to time_t
4833  # To map xsd:dateTime to struct tm, enable the following line:
4834 
4835  # xsd__dateTime = #import "../../custom/struct_tm.h"
4836 
4837  # ... and compile/link with custom/struct_tm.c
4838 
4839 The DOB field is a `xsd:dateTime`, which is bound to `time_t` by default. To
4840 change this to `struct tm`, enable the import of the `xsd__dateTime` custom
4841 serializer by uncommenting the definition of `xsd__dateTime` in
4842 `addresstypemap.dat`. Then change `soap_dateTime2s` to `soap_xsd__dateTime2s`
4843 in the code.
4844 
4845 Building the graph serialization example:
4846 
4847  soapcpp2 -CS -I../../import -p graph graph.h
4848  c++ -I../.. graph.cpp graphC.cpp -o graph -lgsoap++
4849 
4850 To compile without using the `libgsoap++` library: simply compile
4851 `stdsoap2.cpp` together with the above.
4852 
4853 Usage
4854 -----
4855 
4856 To execute the AddressBook example:
4857 
4858  ./address
4859 
4860 To execute the Graph serialization example:
4861 
4862  ./graph
4863