Fix a few issues with the C generator (part 8) (#20378)

* [C] Deprecate *_create() to avoid *_free() confusion

The behaviour of *_free() doesn't match *_create(), so the user should
avoid using them together. But they still need *_free() to clean up
library-allocated objects, so add a _library_owned flag to each struct
as an attempt to tell them apart. This isn't perfect though, because the
user may neglect to zero the field, but they would still see a warning
once in a while so it serves its purpose.

To prevent the new deprecation warnings (intended for the user) from
showing up during the library build itself, define a new family of
*_create_internal() functions, and turn *_create() into simple wrappers.

* Update samples

* add eafer to c technical committee

---------

Co-authored-by: William Cheng <wing328hk@gmail.com>

README.md

@@ -1210,7 +1210,7 @@ If you want to join the committee, please kindly apply by sending an email to te
 | Android               | @jaz-ah (2017/09)                                                                                                                                                                                                                                     |
 | Apex                  |                                                                                                                                                                                                                                                       |
 | Bash                  | @frol (2017/07) @bkryza (2017/08) @kenjones-cisco (2017/09)                                                                                                                                                                                           |
-| C                     | @zhemant (2018/11) @ityuhui (2019/12) @michelealbano (2020/03)                                                                                                                                                                                        |
+| C                     | @zhemant (2018/11) @ityuhui (2019/12) @michelealbano (2020/03) @eafer (2024/12)                                                                                                                                                                                        |
 | C++                   | @ravinikam (2017/07) @stkrwork (2017/07) @etherealjoy (2018/02) @martindelille (2018/03) @muttleyxd (2019/08)                                                                                                                                         |
 | C#                    | @mandrean (2017/08) @shibayan (2020/02) @Blackclaws (2021/03) @lucamazzanti (2021/05) @iBicha (2023/07)                                                                                                                                          |
 | Clojure               |                                                                                                                                                                                                                                                       |

modules/openapi-generator/src/main/resources/C-libcurl/model-body.mustache

@@ -119,7 +119,7 @@ char* {{classname}}_{{name}}_ToString({{projectName}}_{{classVarName}}_{{enumNam
     {{/isContainer}}
     {{/vars}}
 
-{{classname}}_t *{{classname}}_create(
+static {{classname}}_t *{{classname}}_create_internal(
     {{#vars}}
     {{^isContainer}}
     {{^isPrimitiveType}}
@@ -205,14 +205,103 @@ char* {{classname}}_{{name}}_ToString({{projectName}}_{{classVarName}}_{{enumNam
     {{classname}}_local_var->{{{name}}} = {{{name}}};
     {{/vars}}
 
+    {{classname}}_local_var->_library_owned = 1;
     return {{classname}}_local_var;
 }
 
+__attribute__((deprecated)) {{classname}}_t *{{classname}}_create(
+    {{#vars}}
+    {{^isContainer}}
+    {{^isPrimitiveType}}
+    {{#isModel}}
+    {{#isEnum}}
+    {{projectName}}_{{classVarName}}_{{enumName}}_e {{name}}{{^-last}},{{/-last}}
+    {{/isEnum}}
+    {{^isEnum}}
+    {{datatype}}_t *{{name}}{{^-last}},{{/-last}}
+    {{/isEnum}}
+    {{/isModel}}
+    {{^isModel}}
+    {{^isFreeFormObject}}
+    {{^isEnum}}
+    {{datatype}}_t *{{name}}{{^-last}},{{/-last}}
+    {{/isEnum}}
+    {{#isEnum}}
+    {{projectName}}_{{dataType}}_{{enumName}}_e {{name}}{{^-last}},{{/-last}}
+    {{/isEnum}}
+    {{/isFreeFormObject}}
+    {{/isModel}}
+    {{#isUuid}}
+    {{datatype}} *{{name}}{{^-last}},{{/-last}}
+    {{/isUuid}}
+    {{#isEmail}}
+    {{datatype}} *{{name}}{{^-last}},{{/-last}}
+    {{/isEmail}}
+    {{#isFreeFormObject}}
+    {{datatype}}_t *{{name}}{{^-last}},{{/-last}}
+    {{/isFreeFormObject}}
+    {{/isPrimitiveType}}
+    {{#isPrimitiveType}}
+    {{#isNumeric}}
+    {{datatype}} {{name}}{{^-last}},{{/-last}}
+    {{/isNumeric}}
+    {{#isBoolean}}
+    {{datatype}} {{name}}{{^-last}},{{/-last}}
+    {{/isBoolean}}
+    {{#isEnum}}
+    {{#isString}}
+    {{projectName}}_{{classVarName}}_{{enumName}}_e {{name}}{{^-last}},{{/-last}}
+    {{/isString}}
+    {{/isEnum}}
+    {{^isEnum}}
+    {{#isString}}
+    {{datatype}} *{{name}}{{^-last}},{{/-last}}
+    {{/isString}}
+    {{/isEnum}}
+    {{#isByteArray}}
+    {{datatype}} *{{name}}{{^-last}},{{/-last}}
+    {{/isByteArray}}
+    {{#isBinary}}
+    {{datatype}} {{name}}{{^-last}},{{/-last}}
+    {{/isBinary}}
+    {{#isDate}}
+    {{datatype}} *{{name}}{{^-last}},{{/-last}}
+    {{/isDate}}
+    {{#isDateTime}}
+    {{datatype}} *{{name}}{{^-last}},{{/-last}}
+    {{/isDateTime}}
+    {{/isPrimitiveType}}
+    {{/isContainer}}
+    {{#isContainer}}
+    {{#isArray}}
+    {{#isPrimitiveType}}
+    {{datatype}}_t *{{name}}{{^-last}},{{/-last}}
+    {{/isPrimitiveType}}
+    {{^isPrimitiveType}}
+    {{datatype}}_t *{{name}}{{^-last}},{{/-last}}
+    {{/isPrimitiveType}}
+    {{/isArray}}
+    {{#isMap}}
+    {{datatype}} {{name}}{{^-last}},{{/-last}}
+    {{/isMap}}
+    {{/isContainer}}
+    {{/vars}}
+    ) {
+    return {{classname}}_create_internal (
+        {{#vars}}
+        {{name}}{{^-last}},{{/-last}}
+        {{/vars}}
+        );
+}
 
 void {{classname}}_free({{classname}}_t *{{classname}}) {
     if(NULL == {{classname}}){
         return ;
     }
+    if({{classname}}->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "{{classname}}_free");
+        return ;
+    }
     listEntry_t *listEntry;
     {{#vars}}
     {{^isContainer}}
@@ -859,7 +948,7 @@ fail:
 
     {{/vars}}
 
-    {{classname}}_local_var = {{classname}}_create (
+    {{classname}}_local_var = {{classname}}_create_internal (
         {{#vars}}
         {{^isContainer}}
         {{^isPrimitiveType}}

modules/openapi-generator/src/main/resources/C-libcurl/model-header.mustache

@@ -154,9 +154,10 @@ typedef struct {{classname}}_t {
     {{/isContainer}}
     {{/vars}}
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } {{classname}}_t;
 
-{{classname}}_t *{{classname}}_create(
+__attribute__((deprecated)) {{classname}}_t *{{classname}}_create(
     {{#vars}}
     {{^isContainer}}
     {{^isPrimitiveType}}

samples/client/petstore/c-useJsonUnformatted/model/api_response.c

@@ -5,7 +5,7 @@
 
 
 
-api_response_t *api_response_create(
+static api_response_t *api_response_create_internal(
     int code,
     char *type,
     char *message
@@ -18,14 +18,30 @@ api_response_t *api_response_create(
     api_response_local_var->type = type;
     api_response_local_var->message = message;
 
+    api_response_local_var->_library_owned = 1;
     return api_response_local_var;
 }
 
+__attribute__((deprecated)) api_response_t *api_response_create(
+    int code,
+    char *type,
+    char *message
+    ) {
+    return api_response_create_internal (
+        code,
+        type,
+        message
+        );
+}
 
 void api_response_free(api_response_t *api_response) {
     if(NULL == api_response){
         return ;
     }
+    if(api_response->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "api_response_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (api_response->type) {
         free(api_response->type);
@@ -113,7 +129,7 @@ api_response_t *api_response_parseFromJSON(cJSON *api_responseJSON){
     }
 
 
-    api_response_local_var = api_response_create (
+    api_response_local_var = api_response_create_internal (
         code ? code->valuedouble : 0,
         type && !cJSON_IsNull(type) ? strdup(type->valuestring) : NULL,
         message && !cJSON_IsNull(message) ? strdup(message->valuestring) : NULL

samples/client/petstore/c-useJsonUnformatted/model/api_response.h

@@ -23,9 +23,10 @@ typedef struct api_response_t {
     char *type; // string
     char *message; // string
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } api_response_t;
 
-api_response_t *api_response_create(
+__attribute__((deprecated)) api_response_t *api_response_create(
     int code,
     char *type,
     char *message

samples/client/petstore/c-useJsonUnformatted/model/category.c

@@ -5,7 +5,7 @@
 
 
 
-category_t *category_create(
+static category_t *category_create_internal(
     long id,
     char *name
     ) {
@@ -16,14 +16,28 @@ category_t *category_create(
     category_local_var->id = id;
     category_local_var->name = name;
 
+    category_local_var->_library_owned = 1;
     return category_local_var;
 }
 
+__attribute__((deprecated)) category_t *category_create(
+    long id,
+    char *name
+    ) {
+    return category_create_internal (
+        id,
+        name
+        );
+}
 
 void category_free(category_t *category) {
     if(NULL == category){
         return ;
     }
+    if(category->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "category_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (category->name) {
         free(category->name);
@@ -87,7 +101,7 @@ category_t *category_parseFromJSON(cJSON *categoryJSON){
     }
 
 
-    category_local_var = category_create (
+    category_local_var = category_create_internal (
         id ? id->valuedouble : 0,
         name && !cJSON_IsNull(name) ? strdup(name->valuestring) : NULL
         );

samples/client/petstore/c-useJsonUnformatted/model/category.h

@@ -22,9 +22,10 @@ typedef struct category_t {
     long id; //numeric
     char *name; // string
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } category_t;
 
-category_t *category_create(
+__attribute__((deprecated)) category_t *category_create(
     long id,
     char *name
 );

samples/client/petstore/c-useJsonUnformatted/model/mapped_model.c

@@ -5,7 +5,7 @@
 
 
 
-MappedModel_t *MappedModel_create(
+static MappedModel_t *MappedModel_create_internal(
     int another_property,
     char *uuid_property
     ) {
@@ -16,14 +16,28 @@ MappedModel_t *MappedModel_create(
     MappedModel_local_var->another_property = another_property;
     MappedModel_local_var->uuid_property = uuid_property;
 
+    MappedModel_local_var->_library_owned = 1;
     return MappedModel_local_var;
 }
 
+__attribute__((deprecated)) MappedModel_t *MappedModel_create(
+    int another_property,
+    char *uuid_property
+    ) {
+    return MappedModel_create_internal (
+        another_property,
+        uuid_property
+        );
+}
 
 void MappedModel_free(MappedModel_t *MappedModel) {
     if(NULL == MappedModel){
         return ;
     }
+    if(MappedModel->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "MappedModel_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (MappedModel->uuid_property) {
         free(MappedModel->uuid_property);
@@ -87,7 +101,7 @@ MappedModel_t *MappedModel_parseFromJSON(cJSON *MappedModelJSON){
     }
 
 
-    MappedModel_local_var = MappedModel_create (
+    MappedModel_local_var = MappedModel_create_internal (
         another_property ? another_property->valuedouble : 0,
         uuid_property && !cJSON_IsNull(uuid_property) ? strdup(uuid_property->valuestring) : NULL
         );

samples/client/petstore/c-useJsonUnformatted/model/mapped_model.h

@@ -22,9 +22,10 @@ typedef struct MappedModel_t {
     int another_property; //numeric
     char *uuid_property; // string
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } MappedModel_t;
 
-MappedModel_t *MappedModel_create(
+__attribute__((deprecated)) MappedModel_t *MappedModel_create(
     int another_property,
     char *uuid_property
 );

samples/client/petstore/c-useJsonUnformatted/model/model_with_set_propertes.c

@@ -5,7 +5,7 @@
 
 
 
-model_with_set_propertes_t *model_with_set_propertes_create(
+static model_with_set_propertes_t *model_with_set_propertes_create_internal(
     list_t *tag_set,
     list_t *string_set
     ) {
@@ -16,14 +16,28 @@ model_with_set_propertes_t *model_with_set_propertes_create(
     model_with_set_propertes_local_var->tag_set = tag_set;
     model_with_set_propertes_local_var->string_set = string_set;
 
+    model_with_set_propertes_local_var->_library_owned = 1;
     return model_with_set_propertes_local_var;
 }
 
+__attribute__((deprecated)) model_with_set_propertes_t *model_with_set_propertes_create(
+    list_t *tag_set,
+    list_t *string_set
+    ) {
+    return model_with_set_propertes_create_internal (
+        tag_set,
+        string_set
+        );
+}
 
 void model_with_set_propertes_free(model_with_set_propertes_t *model_with_set_propertes) {
     if(NULL == model_with_set_propertes){
         return ;
     }
+    if(model_with_set_propertes->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "model_with_set_propertes_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (model_with_set_propertes->tag_set) {
         list_ForEach(listEntry, model_with_set_propertes->tag_set) {
@@ -146,7 +160,7 @@ model_with_set_propertes_t *model_with_set_propertes_parseFromJSON(cJSON *model_
     }
 
 
-    model_with_set_propertes_local_var = model_with_set_propertes_create (
+    model_with_set_propertes_local_var = model_with_set_propertes_create_internal (
         tag_set ? tag_setList : NULL,
         string_set ? string_setList : NULL
         );

samples/client/petstore/c-useJsonUnformatted/model/model_with_set_propertes.h

@@ -23,9 +23,10 @@ typedef struct model_with_set_propertes_t {
     list_t *tag_set; //nonprimitive container
     list_t *string_set; //primitive container
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } model_with_set_propertes_t;
 
-model_with_set_propertes_t *model_with_set_propertes_create(
+__attribute__((deprecated)) model_with_set_propertes_t *model_with_set_propertes_create(
     list_t *tag_set,
     list_t *string_set
 );

samples/client/petstore/c-useJsonUnformatted/model/order.c

@@ -22,7 +22,7 @@ openapi_petstore_order_STATUS_e order_status_FromString(char* status){
     return 0;
 }
 
-order_t *order_create(
+static order_t *order_create_internal(
     long id,
     long pet_id,
     int quantity,
@@ -41,14 +41,36 @@ order_t *order_create(
     order_local_var->status = status;
     order_local_var->complete = complete;
 
+    order_local_var->_library_owned = 1;
     return order_local_var;
 }
 
+__attribute__((deprecated)) order_t *order_create(
+    long id,
+    long pet_id,
+    int quantity,
+    char *ship_date,
+    openapi_petstore_order_STATUS_e status,
+    int complete
+    ) {
+    return order_create_internal (
+        id,
+        pet_id,
+        quantity,
+        ship_date,
+        status,
+        complete
+        );
+}
 
 void order_free(order_t *order) {
     if(NULL == order){
         return ;
     }
+    if(order->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "order_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (order->ship_date) {
         free(order->ship_date);
@@ -195,7 +217,7 @@ order_t *order_parseFromJSON(cJSON *orderJSON){
     }
 
 
-    order_local_var = order_create (
+    order_local_var = order_create_internal (
         id ? id->valuedouble : 0,
         pet_id ? pet_id->valuedouble : 0,
         quantity ? quantity->valuedouble : 0,

samples/client/petstore/c-useJsonUnformatted/model/order.h

@@ -34,9 +34,10 @@ typedef struct order_t {
     openapi_petstore_order_STATUS_e status; //enum
     int complete; //boolean
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } order_t;
 
-order_t *order_create(
+__attribute__((deprecated)) order_t *order_create(
     long id,
     long pet_id,
     int quantity,

samples/client/petstore/c-useJsonUnformatted/model/pet.c

@@ -22,7 +22,7 @@ openapi_petstore_pet_STATUS_e pet_status_FromString(char* status){
     return 0;
 }
 
-pet_t *pet_create(
+static pet_t *pet_create_internal(
     long id,
     category_t *category,
     char *name,
@@ -41,14 +41,36 @@ pet_t *pet_create(
     pet_local_var->tags = tags;
     pet_local_var->status = status;
 
+    pet_local_var->_library_owned = 1;
     return pet_local_var;
 }
 
+__attribute__((deprecated)) pet_t *pet_create(
+    long id,
+    category_t *category,
+    char *name,
+    list_t *photo_urls,
+    list_t *tags,
+    openapi_petstore_pet_STATUS_e status
+    ) {
+    return pet_create_internal (
+        id,
+        category,
+        name,
+        photo_urls,
+        tags,
+        status
+        );
+}
 
 void pet_free(pet_t *pet) {
     if(NULL == pet){
         return ;
     }
+    if(pet->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "pet_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (pet->category) {
         category_free(pet->category);
@@ -275,7 +297,7 @@ pet_t *pet_parseFromJSON(cJSON *petJSON){
     }
 
 
-    pet_local_var = pet_create (
+    pet_local_var = pet_create_internal (
         id ? id->valuedouble : 0,
         category ? category_local_nonprim : NULL,
         strdup(name->valuestring),

samples/client/petstore/c-useJsonUnformatted/model/pet.h

@@ -36,9 +36,10 @@ typedef struct pet_t {
     list_t *tags; //nonprimitive container
     openapi_petstore_pet_STATUS_e status; //enum
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } pet_t;
 
-pet_t *pet_create(
+__attribute__((deprecated)) pet_t *pet_create(
     long id,
     category_t *category,
     char *name,

samples/client/petstore/c-useJsonUnformatted/model/tag.c

@@ -5,7 +5,7 @@
 
 
 
-tag_t *tag_create(
+static tag_t *tag_create_internal(
     long id,
     char *name
     ) {
@@ -16,14 +16,28 @@ tag_t *tag_create(
     tag_local_var->id = id;
     tag_local_var->name = name;
 
+    tag_local_var->_library_owned = 1;
     return tag_local_var;
 }
 
+__attribute__((deprecated)) tag_t *tag_create(
+    long id,
+    char *name
+    ) {
+    return tag_create_internal (
+        id,
+        name
+        );
+}
 
 void tag_free(tag_t *tag) {
     if(NULL == tag){
         return ;
     }
+    if(tag->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "tag_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (tag->name) {
         free(tag->name);
@@ -87,7 +101,7 @@ tag_t *tag_parseFromJSON(cJSON *tagJSON){
     }
 
 
-    tag_local_var = tag_create (
+    tag_local_var = tag_create_internal (
         id ? id->valuedouble : 0,
         name && !cJSON_IsNull(name) ? strdup(name->valuestring) : NULL
         );

samples/client/petstore/c-useJsonUnformatted/model/tag.h

@@ -22,9 +22,10 @@ typedef struct tag_t {
     long id; //numeric
     char *name; // string
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } tag_t;
 
-tag_t *tag_create(
+__attribute__((deprecated)) tag_t *tag_create(
     long id,
     char *name
 );

samples/client/petstore/c-useJsonUnformatted/model/user.c

@@ -5,7 +5,7 @@
 
 
 
-user_t *user_create(
+static user_t *user_create_internal(
     long id,
     char *username,
     char *first_name,
@@ -32,14 +32,44 @@ user_t *user_create(
     user_local_var->extra = extra;
     user_local_var->preference = preference;
 
+    user_local_var->_library_owned = 1;
     return user_local_var;
 }
 
+__attribute__((deprecated)) user_t *user_create(
+    long id,
+    char *username,
+    char *first_name,
+    char *last_name,
+    char *email,
+    char *password,
+    char *phone,
+    int user_status,
+    list_t* extra,
+    openapi_petstore_preference__e preference
+    ) {
+    return user_create_internal (
+        id,
+        username,
+        first_name,
+        last_name,
+        email,
+        password,
+        phone,
+        user_status,
+        extra,
+        preference
+        );
+}
 
 void user_free(user_t *user) {
     if(NULL == user){
         return ;
     }
+    if(user->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "user_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (user->username) {
         free(user->username);
@@ -320,7 +350,7 @@ user_t *user_parseFromJSON(cJSON *userJSON){
     }
 
 
-    user_local_var = user_create (
+    user_local_var = user_create_internal (
         id ? id->valuedouble : 0,
         username && !cJSON_IsNull(username) ? strdup(username->valuestring) : NULL,
         first_name && !cJSON_IsNull(first_name) ? strdup(first_name->valuestring) : NULL,

samples/client/petstore/c-useJsonUnformatted/model/user.h

@@ -32,9 +32,10 @@ typedef struct user_t {
     list_t* extra; //map
     openapi_petstore_preference__e preference; //referenced enum
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } user_t;
 
-user_t *user_create(
+__attribute__((deprecated)) user_t *user_create(
     long id,
     char *username,
     char *first_name,

samples/client/petstore/c/model/api_response.c

@@ -5,7 +5,7 @@
 
 
 
-api_response_t *api_response_create(
+static api_response_t *api_response_create_internal(
     int code,
     char *type,
     char *message
@@ -18,14 +18,30 @@ api_response_t *api_response_create(
     api_response_local_var->type = type;
     api_response_local_var->message = message;
 
+    api_response_local_var->_library_owned = 1;
     return api_response_local_var;
 }
 
+__attribute__((deprecated)) api_response_t *api_response_create(
+    int code,
+    char *type,
+    char *message
+    ) {
+    return api_response_create_internal (
+        code,
+        type,
+        message
+        );
+}
 
 void api_response_free(api_response_t *api_response) {
     if(NULL == api_response){
         return ;
     }
+    if(api_response->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "api_response_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (api_response->type) {
         free(api_response->type);
@@ -113,7 +129,7 @@ api_response_t *api_response_parseFromJSON(cJSON *api_responseJSON){
     }
 
 
-    api_response_local_var = api_response_create (
+    api_response_local_var = api_response_create_internal (
         code ? code->valuedouble : 0,
         type && !cJSON_IsNull(type) ? strdup(type->valuestring) : NULL,
         message && !cJSON_IsNull(message) ? strdup(message->valuestring) : NULL

samples/client/petstore/c/model/api_response.h

@@ -23,9 +23,10 @@ typedef struct api_response_t {
     char *type; // string
     char *message; // string
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } api_response_t;
 
-api_response_t *api_response_create(
+__attribute__((deprecated)) api_response_t *api_response_create(
     int code,
     char *type,
     char *message

samples/client/petstore/c/model/category.c

@@ -5,7 +5,7 @@
 
 
 
-category_t *category_create(
+static category_t *category_create_internal(
     long id,
     char *name
     ) {
@@ -16,14 +16,28 @@ category_t *category_create(
     category_local_var->id = id;
     category_local_var->name = name;
 
+    category_local_var->_library_owned = 1;
     return category_local_var;
 }
 
+__attribute__((deprecated)) category_t *category_create(
+    long id,
+    char *name
+    ) {
+    return category_create_internal (
+        id,
+        name
+        );
+}
 
 void category_free(category_t *category) {
     if(NULL == category){
         return ;
     }
+    if(category->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "category_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (category->name) {
         free(category->name);
@@ -87,7 +101,7 @@ category_t *category_parseFromJSON(cJSON *categoryJSON){
     }
 
 
-    category_local_var = category_create (
+    category_local_var = category_create_internal (
         id ? id->valuedouble : 0,
         name && !cJSON_IsNull(name) ? strdup(name->valuestring) : NULL
         );

samples/client/petstore/c/model/category.h

@@ -22,9 +22,10 @@ typedef struct category_t {
     long id; //numeric
     char *name; // string
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } category_t;
 
-category_t *category_create(
+__attribute__((deprecated)) category_t *category_create(
     long id,
     char *name
 );

samples/client/petstore/c/model/mapped_model.c

@@ -5,7 +5,7 @@
 
 
 
-MappedModel_t *MappedModel_create(
+static MappedModel_t *MappedModel_create_internal(
     int another_property,
     char *uuid_property
     ) {
@@ -16,14 +16,28 @@ MappedModel_t *MappedModel_create(
     MappedModel_local_var->another_property = another_property;
     MappedModel_local_var->uuid_property = uuid_property;
 
+    MappedModel_local_var->_library_owned = 1;
     return MappedModel_local_var;
 }
 
+__attribute__((deprecated)) MappedModel_t *MappedModel_create(
+    int another_property,
+    char *uuid_property
+    ) {
+    return MappedModel_create_internal (
+        another_property,
+        uuid_property
+        );
+}
 
 void MappedModel_free(MappedModel_t *MappedModel) {
     if(NULL == MappedModel){
         return ;
     }
+    if(MappedModel->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "MappedModel_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (MappedModel->uuid_property) {
         free(MappedModel->uuid_property);
@@ -87,7 +101,7 @@ MappedModel_t *MappedModel_parseFromJSON(cJSON *MappedModelJSON){
     }
 
 
-    MappedModel_local_var = MappedModel_create (
+    MappedModel_local_var = MappedModel_create_internal (
         another_property ? another_property->valuedouble : 0,
         uuid_property && !cJSON_IsNull(uuid_property) ? strdup(uuid_property->valuestring) : NULL
         );

samples/client/petstore/c/model/mapped_model.h

@@ -22,9 +22,10 @@ typedef struct MappedModel_t {
     int another_property; //numeric
     char *uuid_property; // string
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } MappedModel_t;
 
-MappedModel_t *MappedModel_create(
+__attribute__((deprecated)) MappedModel_t *MappedModel_create(
     int another_property,
     char *uuid_property
 );

samples/client/petstore/c/model/model_with_set_propertes.c

@@ -5,7 +5,7 @@
 
 
 
-model_with_set_propertes_t *model_with_set_propertes_create(
+static model_with_set_propertes_t *model_with_set_propertes_create_internal(
     list_t *tag_set,
     list_t *string_set
     ) {
@@ -16,14 +16,28 @@ model_with_set_propertes_t *model_with_set_propertes_create(
     model_with_set_propertes_local_var->tag_set = tag_set;
     model_with_set_propertes_local_var->string_set = string_set;
 
+    model_with_set_propertes_local_var->_library_owned = 1;
     return model_with_set_propertes_local_var;
 }
 
+__attribute__((deprecated)) model_with_set_propertes_t *model_with_set_propertes_create(
+    list_t *tag_set,
+    list_t *string_set
+    ) {
+    return model_with_set_propertes_create_internal (
+        tag_set,
+        string_set
+        );
+}
 
 void model_with_set_propertes_free(model_with_set_propertes_t *model_with_set_propertes) {
     if(NULL == model_with_set_propertes){
         return ;
     }
+    if(model_with_set_propertes->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "model_with_set_propertes_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (model_with_set_propertes->tag_set) {
         list_ForEach(listEntry, model_with_set_propertes->tag_set) {
@@ -146,7 +160,7 @@ model_with_set_propertes_t *model_with_set_propertes_parseFromJSON(cJSON *model_
     }
 
 
-    model_with_set_propertes_local_var = model_with_set_propertes_create (
+    model_with_set_propertes_local_var = model_with_set_propertes_create_internal (
         tag_set ? tag_setList : NULL,
         string_set ? string_setList : NULL
         );

samples/client/petstore/c/model/model_with_set_propertes.h

@@ -23,9 +23,10 @@ typedef struct model_with_set_propertes_t {
     list_t *tag_set; //nonprimitive container
     list_t *string_set; //primitive container
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } model_with_set_propertes_t;
 
-model_with_set_propertes_t *model_with_set_propertes_create(
+__attribute__((deprecated)) model_with_set_propertes_t *model_with_set_propertes_create(
     list_t *tag_set,
     list_t *string_set
 );

samples/client/petstore/c/model/order.c

@@ -22,7 +22,7 @@ openapi_petstore_order_STATUS_e order_status_FromString(char* status){
     return 0;
 }
 
-order_t *order_create(
+static order_t *order_create_internal(
     long id,
     long pet_id,
     int quantity,
@@ -41,14 +41,36 @@ order_t *order_create(
     order_local_var->status = status;
     order_local_var->complete = complete;
 
+    order_local_var->_library_owned = 1;
     return order_local_var;
 }
 
+__attribute__((deprecated)) order_t *order_create(
+    long id,
+    long pet_id,
+    int quantity,
+    char *ship_date,
+    openapi_petstore_order_STATUS_e status,
+    int complete
+    ) {
+    return order_create_internal (
+        id,
+        pet_id,
+        quantity,
+        ship_date,
+        status,
+        complete
+        );
+}
 
 void order_free(order_t *order) {
     if(NULL == order){
         return ;
     }
+    if(order->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "order_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (order->ship_date) {
         free(order->ship_date);
@@ -195,7 +217,7 @@ order_t *order_parseFromJSON(cJSON *orderJSON){
     }
 
 
-    order_local_var = order_create (
+    order_local_var = order_create_internal (
         id ? id->valuedouble : 0,
         pet_id ? pet_id->valuedouble : 0,
         quantity ? quantity->valuedouble : 0,

samples/client/petstore/c/model/order.h

@@ -34,9 +34,10 @@ typedef struct order_t {
     openapi_petstore_order_STATUS_e status; //enum
     int complete; //boolean
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } order_t;
 
-order_t *order_create(
+__attribute__((deprecated)) order_t *order_create(
     long id,
     long pet_id,
     int quantity,

samples/client/petstore/c/model/pet.c

@@ -22,7 +22,7 @@ openapi_petstore_pet_STATUS_e pet_status_FromString(char* status){
     return 0;
 }
 
-pet_t *pet_create(
+static pet_t *pet_create_internal(
     long id,
     category_t *category,
     char *name,
@@ -41,14 +41,36 @@ pet_t *pet_create(
     pet_local_var->tags = tags;
     pet_local_var->status = status;
 
+    pet_local_var->_library_owned = 1;
     return pet_local_var;
 }
 
+__attribute__((deprecated)) pet_t *pet_create(
+    long id,
+    category_t *category,
+    char *name,
+    list_t *photo_urls,
+    list_t *tags,
+    openapi_petstore_pet_STATUS_e status
+    ) {
+    return pet_create_internal (
+        id,
+        category,
+        name,
+        photo_urls,
+        tags,
+        status
+        );
+}
 
 void pet_free(pet_t *pet) {
     if(NULL == pet){
         return ;
     }
+    if(pet->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "pet_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (pet->category) {
         category_free(pet->category);
@@ -275,7 +297,7 @@ pet_t *pet_parseFromJSON(cJSON *petJSON){
     }
 
 
-    pet_local_var = pet_create (
+    pet_local_var = pet_create_internal (
         id ? id->valuedouble : 0,
         category ? category_local_nonprim : NULL,
         strdup(name->valuestring),

samples/client/petstore/c/model/pet.h

@@ -36,9 +36,10 @@ typedef struct pet_t {
     list_t *tags; //nonprimitive container
     openapi_petstore_pet_STATUS_e status; //enum
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } pet_t;
 
-pet_t *pet_create(
+__attribute__((deprecated)) pet_t *pet_create(
     long id,
     category_t *category,
     char *name,

samples/client/petstore/c/model/tag.c

@@ -5,7 +5,7 @@
 
 
 
-tag_t *tag_create(
+static tag_t *tag_create_internal(
     long id,
     char *name
     ) {
@@ -16,14 +16,28 @@ tag_t *tag_create(
     tag_local_var->id = id;
     tag_local_var->name = name;
 
+    tag_local_var->_library_owned = 1;
     return tag_local_var;
 }
 
+__attribute__((deprecated)) tag_t *tag_create(
+    long id,
+    char *name
+    ) {
+    return tag_create_internal (
+        id,
+        name
+        );
+}
 
 void tag_free(tag_t *tag) {
     if(NULL == tag){
         return ;
     }
+    if(tag->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "tag_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (tag->name) {
         free(tag->name);
@@ -87,7 +101,7 @@ tag_t *tag_parseFromJSON(cJSON *tagJSON){
     }
 
 
-    tag_local_var = tag_create (
+    tag_local_var = tag_create_internal (
         id ? id->valuedouble : 0,
         name && !cJSON_IsNull(name) ? strdup(name->valuestring) : NULL
         );

samples/client/petstore/c/model/tag.h

@@ -22,9 +22,10 @@ typedef struct tag_t {
     long id; //numeric
     char *name; // string
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } tag_t;
 
-tag_t *tag_create(
+__attribute__((deprecated)) tag_t *tag_create(
     long id,
     char *name
 );

samples/client/petstore/c/model/user.c

@@ -5,7 +5,7 @@
 
 
 
-user_t *user_create(
+static user_t *user_create_internal(
     long id,
     char *username,
     char *first_name,
@@ -32,14 +32,44 @@ user_t *user_create(
     user_local_var->extra = extra;
     user_local_var->preference = preference;
 
+    user_local_var->_library_owned = 1;
     return user_local_var;
 }
 
+__attribute__((deprecated)) user_t *user_create(
+    long id,
+    char *username,
+    char *first_name,
+    char *last_name,
+    char *email,
+    char *password,
+    char *phone,
+    int user_status,
+    list_t* extra,
+    openapi_petstore_preference__e preference
+    ) {
+    return user_create_internal (
+        id,
+        username,
+        first_name,
+        last_name,
+        email,
+        password,
+        phone,
+        user_status,
+        extra,
+        preference
+        );
+}
 
 void user_free(user_t *user) {
     if(NULL == user){
         return ;
     }
+    if(user->_library_owned != 1){
+        fprintf(stderr, "WARNING: %s() does NOT free objects allocated by the user\n", "user_free");
+        return ;
+    }
     listEntry_t *listEntry;
     if (user->username) {
         free(user->username);
@@ -320,7 +350,7 @@ user_t *user_parseFromJSON(cJSON *userJSON){
     }
 
 
-    user_local_var = user_create (
+    user_local_var = user_create_internal (
         id ? id->valuedouble : 0,
         username && !cJSON_IsNull(username) ? strdup(username->valuestring) : NULL,
         first_name && !cJSON_IsNull(first_name) ? strdup(first_name->valuestring) : NULL,

samples/client/petstore/c/model/user.h

@@ -32,9 +32,10 @@ typedef struct user_t {
     list_t* extra; //map
     openapi_petstore_preference__e preference; //referenced enum
 
+    int _library_owned; // Is the library responsible for freeing this object?
 } user_t;
 
-user_t *user_create(
+__attribute__((deprecated)) user_t *user_create(
     long id,
     char *username,
     char *first_name,