Dynamic Subscription (BONUS: Allocators): rosidl (#737)

* Add zero init for message type support handle

Signed-off-by: methylDragon <methylDragon@gmail.com>

* Fix memory leaks in type description utils

Signed-off-by: methylDragon <methylDragon@gmail.com>

* Refactor serialization support to use allocators and refs

Signed-off-by: methylDragon <methylDragon@gmail.com>

* Check if allocator is valid

Signed-off-by: methylDragon <methylDragon@gmail.com>

---------

Signed-off-by: methylDragon <methylDragon@gmail.com>

Author: methylDragon

rosidl_runtime_c/include/rosidl_runtime_c/message_type_support_struct.h

@@ -57,6 +57,10 @@ struct rosidl_message_type_support_t
   rosidl_message_get_type_description_sources_function get_type_description_sources_func;
 };
 
+/// Return a rosidl_message_type_support_t struct with members set to `NULL`.
+ROSIDL_GENERATOR_C_PUBLIC
+rosidl_message_type_support_t rosidl_get_zero_initialized_message_type_support_handle(void);
+
 /// Get the message type support handle specific to this identifier.
 /**
  * The handle's message typesupport identifier function is returned or if the parameters are NULL

rosidl_runtime_c/src/message_type_support.c

@@ -18,6 +18,19 @@
 #include <stdio.h>
 #include <string.h>
 
+rosidl_message_type_support_t rosidl_get_zero_initialized_message_type_support_handle(void)
+{
+  static rosidl_message_type_support_t null_message_type_support = {
+    .typesupport_identifier = NULL,
+    .data = NULL,
+    .func = NULL,
+    .get_type_hash_func = NULL,
+    .get_type_description_func = NULL,
+    .get_type_description_sources_func = NULL
+  };
+  return null_message_type_support;
+}
+
 const rosidl_message_type_support_t * get_message_typesupport_handle(
   const rosidl_message_type_support_t * handle, const char * identifier)
 {

rosidl_runtime_c/src/type_description_utils.c

@@ -112,6 +112,10 @@ rosidl_runtime_c_type_description_utils_get_field_map(
 {
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(individual_description, RCUTILS_RET_INVALID_ARGUMENT);
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(allocator, RCUTILS_RET_INVALID_ARGUMENT);
+  if (!rcutils_allocator_is_valid(allocator)) {
+    RCUTILS_SET_ERROR_MSG("allocator is invalid");
+    return RCUTILS_RET_INVALID_ARGUMENT;
+  }
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(hash_map, RCUTILS_RET_INVALID_ARGUMENT);
   if (*hash_map != NULL) {
     RCUTILS_SET_ERROR_MSG("'hash_map' output argument is not pointing to null");
@@ -176,6 +180,10 @@ rosidl_runtime_c_type_description_utils_get_referenced_type_description_map(
 {
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(referenced_types, RCUTILS_RET_INVALID_ARGUMENT);
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(allocator, RCUTILS_RET_INVALID_ARGUMENT);
+  if (!rcutils_allocator_is_valid(allocator)) {
+    RCUTILS_SET_ERROR_MSG("allocator is invalid");
+    return RCUTILS_RET_INVALID_ARGUMENT;
+  }
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(hash_map, RCUTILS_RET_INVALID_ARGUMENT);
   if (*hash_map != NULL) {
     RCUTILS_SET_ERROR_MSG("'hash_map' output argument is not pointing to null");
@@ -277,6 +285,10 @@ rosidl_runtime_c_type_description_utils_get_necessary_referenced_type_descriptio
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(main_type_description, RCUTILS_RET_INVALID_ARGUMENT);
   HASH_MAP_VALIDATE_HASH_MAP(referenced_types_map);
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(allocator, RCUTILS_RET_INVALID_ARGUMENT);
+  if (!rcutils_allocator_is_valid(allocator)) {
+    RCUTILS_SET_ERROR_MSG("allocator is invalid");
+    return RCUTILS_RET_INVALID_ARGUMENT;
+  }
   RCUTILS_CHECK_ARGUMENT_FOR_NULL(seen_map, RCUTILS_RET_INVALID_ARGUMENT);
 
   // Only true for the top level call, so we can determine when to finalize the map
@@ -693,6 +705,13 @@ rosidl_runtime_c_type_description_utils_individual_type_description_is_valid(
     goto end;
   }
 
+  ret = rcutils_hash_map_fini(hash_map);
+  if (ret != RCUTILS_RET_OK) {
+    RCUTILS_SET_ERROR_MSG("Could not finalize hash map");
+    return ret;
+  }
+  allocator.deallocate(hash_map, allocator.state);
+
   return RCUTILS_RET_OK;
 
 end:
@@ -853,7 +872,7 @@ rosidl_runtime_c_type_description_utils_type_description_is_valid(
     goto end_sequence;
   }
 
-  return RCUTILS_RET_OK;
+  ret = RCUTILS_RET_OK;
 
 end_sequence:
   rosidl_runtime_c__type_description__IndividualTypeDescription__Sequence__destroy(sorted_sequence);