[C][Client]Fix coredump in multi-thread environment (#7835)

modules/openapi-generator/src/main/resources/C-libcurl/apiClient.c.mustache

@@ -7,7 +7,6 @@
 size_t writeDataCallback(void *buffer, size_t size, size_t nmemb, void *userp);
 
 apiClient_t *apiClient_create() {
-    curl_global_init(CURL_GLOBAL_ALL);
     apiClient_t *apiClient = malloc(sizeof(apiClient_t));
     apiClient->basePath = strdup("{{{basePath}}}");
     apiClient->sslConfig = NULL;
@@ -43,7 +42,6 @@ apiClient_t *apiClient_create_with_base_path(const char *basePath
 {{/authMethods}}
 {{/hasAuthMethods}}
 ) {
-    curl_global_init(CURL_GLOBAL_ALL);
     apiClient_t *apiClient = malloc(sizeof(apiClient_t));
     if(basePath){
         apiClient->basePath = strdup(basePath);
@@ -128,7 +126,6 @@ void apiClient_free(apiClient_t *apiClient) {
     {{/authMethods}}
     {{/hasAuthMethods}}
     free(apiClient);
-    curl_global_cleanup();
 }
 
 sslConfig_t *sslConfig_create(const char *clientCertFile, const char *clientKeyFile, const char *CACertFile, int insecureSkipTlsVerify) {
@@ -620,3 +617,10 @@ char *strReplace(char *orig, char *rep, char *with) {
     return result;
 }
 
+void apiClient_setupGlobalEnv() {
+    curl_global_init(CURL_GLOBAL_ALL);
+}
+
+void apiClient_unsetupGlobalEnv() {
+    curl_global_cleanup();
+}

modules/openapi-generator/src/main/resources/C-libcurl/apiClient.h.mustache

@@ -64,4 +64,16 @@ void sslConfig_free(sslConfig_t *sslConfig);
 
 char *strReplace(char *orig, char *rep, char *with);
 
+/*
+ * In single thread program, the function apiClient_setupGlobalEnv is not needed.
+ * But in multi-thread program, apiClient_setupGlobalEnv must be called before any worker thread is created
+ */
+void apiClient_setupGlobalEnv();
+
+/*
+ * This function apiClient_unsetupGlobalEnv must be called whether single or multiple program.
+ * In multi-thread program, it is must be called after all worker threads end.
+ */
+void apiClient_unsetupGlobalEnv();
+
 #endif // INCLUDE_API_CLIENT_H

samples/client/petstore/c/include/apiClient.h

@@ -46,4 +46,16 @@ void sslConfig_free(sslConfig_t *sslConfig);
 
 char *strReplace(char *orig, char *rep, char *with);
 
+/*
+ * In single thread program, the function apiClient_setupGlobalEnv is not needed.
+ * But in multi-thread program, apiClient_setupGlobalEnv must be called before any worker thread is created
+ */
+void apiClient_setupGlobalEnv();
+
+/*
+ * This function apiClient_unsetupGlobalEnv must be called whether single or multiple program.
+ * In multi-thread program, it is must be called after all worker threads end.
+ */
+void apiClient_unsetupGlobalEnv();
+
 #endif // INCLUDE_API_CLIENT_H

samples/client/petstore/c/src/apiClient.c

@@ -7,7 +7,6 @@
 size_t writeDataCallback(void *buffer, size_t size, size_t nmemb, void *userp);
 
 apiClient_t *apiClient_create() {
-    curl_global_init(CURL_GLOBAL_ALL);
     apiClient_t *apiClient = malloc(sizeof(apiClient_t));
     apiClient->basePath = strdup("http://petstore.swagger.io/v2");
     apiClient->sslConfig = NULL;
@@ -25,7 +24,6 @@ apiClient_t *apiClient_create_with_base_path(const char *basePath
 , sslConfig_t *sslConfig
 , list_t *apiKeys_api_key
 ) {
-    curl_global_init(CURL_GLOBAL_ALL);
     apiClient_t *apiClient = malloc(sizeof(apiClient_t));
     if(basePath){
         apiClient->basePath = strdup(basePath);
@@ -82,7 +80,6 @@ void apiClient_free(apiClient_t *apiClient) {
         free(apiClient->accessToken);
     }
     free(apiClient);
-    curl_global_cleanup();
 }
 
 sslConfig_t *sslConfig_create(const char *clientCertFile, const char *clientKeyFile, const char *CACertFile, int insecureSkipTlsVerify) {
@@ -526,3 +523,10 @@ char *strReplace(char *orig, char *rep, char *with) {
     return result;
 }
 
+void apiClient_setupGlobalEnv() {
+    curl_global_init(CURL_GLOBAL_ALL);
+}
+
+void apiClient_unsetupGlobalEnv() {
+    curl_global_cleanup();
+}

samples/client/petstore/c/unit-tests/manual-PetAPI.c

@@ -139,4 +139,6 @@ int main() {
 		fclose(file);
 	}
 	apiClient_free(apiClient3);
+
+	apiClient_unsetupGlobalEnv();
 }

samples/client/petstore/c/unit-tests/manual-StoreAPI.c

@@ -100,4 +100,6 @@ int main() {
 	}
 	list_free(elementToReturn);
 	apiClient_free(apiClient5);
+
+	apiClient_unsetupGlobalEnv();
 }

samples/client/petstore/c/unit-tests/manual-UserAPI.c

@@ -120,4 +120,6 @@ int main() {
 
 	UserAPI_deleteUser(apiClient5, "example123");
 	apiClient_free(apiClient5);
+
+	apiClient_unsetupGlobalEnv();
 }