Add type hash to rmw_topic_endpoint_info_t (rep2011)

rmw/include/rmw/topic_endpoint_info.h

@@ -21,6 +21,7 @@ extern "C"
 #endif
 
 #include "rcutils/allocator.h"
+#include "rosidl_runtime_c/type_hash.h"
 #include "rmw/types.h"
 #include "rmw/visibility_control.h"
 
@@ -33,8 +34,10 @@ typedef struct RMW_PUBLIC_TYPE rmw_topic_endpoint_info_s
   const char * node_name;
   /// Namespace of the node
   const char * node_namespace;
-  /// The associated topic type
+  /// The associated topic type's name
   const char * topic_type;
+  /// Hashed value for topic type's description
+  rosidl_type_hash_t topic_type_hash;
   /// The endpoint type
   rmw_endpoint_type_t endpoint_type;
   /// The GID of the endpoint
@@ -55,7 +58,7 @@ rmw_get_zero_initialized_topic_endpoint_info(void);
 
 /// Finalize a topic endpoint info data structure.
 /**
- * This function deallocates all allocated members of the given data structure,
+ * Deallocates all allocated members of the given data structure,
  * and then zero initializes it.
  * If a logical error, such as `RMW_RET_INVALID_ARGUMENT`, ensues, this function
  * will return early, leaving the given data structure unchanged.
@@ -94,8 +97,8 @@ rmw_topic_endpoint_info_fini(
 
 /// Set the topic type in the given topic endpoint info data structure.
 /**
- * This functions allocates memory and copies the value of the `topic_type`
- * argument to set the data structure `topic_type` member.
+ * Allocates memory and copies the value of the `topic_type`
+ * argument to set the data structure's `topic_type` member.
  *
  * <hr>
  * Attribute          | Adherence
@@ -135,10 +138,45 @@ rmw_topic_endpoint_info_set_topic_type(
   const char * topic_type,
   rcutils_allocator_t * allocator);
 
+/// Set the topic type hash in the given topic endpoint info data structure.
+/**
+ * Assigns the value of the `topic_type_hash` argument to the data structure's
+ * `topic_type_hash` member.
+ *
+ * <hr>
+ * Attribute          | Adherence
+ * ------------------ | -------------
+ * Allocates Memory   | No
+ * Thread-Safe        | No
+ * Uses Atomics       | No
+ * Lock-Free          | Yes
+ *
+ * \par Thread-safety
+ *   Setting a member is a reentrant procedure, but:
+ *   - Access to the topic endpoint info data structure is not synchronized.
+ *     It is not safe to read or write the `topic_type_hash` member of the given `topic_endpoint`
+ *     while setting it.
+ *     Concurrent `topic_type_hash` reads are safe, but concurrent reads and writes are not.
+ *
+ * \param[inout] topic_endpoint_info Data structure to be populated.
+ * \param[in] topic_type_hash Topic type hash to be copied.
+ * \returns `RMW_RET_OK` if successful, or
+ * \returns `RMW_RET_INVALID_ARGUMENT` if `topic_endpoint_info` is NULL, or
+ * \returns `RMW_RET_INVALID_ARGUMENT` if `topic_type_hash` is NULL, or
+ * \returns `RMW_RET_ERROR` when an unspecified error occurs.
+ * \remark This function sets the RMW error state on failure.
+ */
+RMW_PUBLIC
+RMW_WARN_UNUSED
+rmw_ret_t
+rmw_topic_endpoint_info_set_topic_type_hash(
+  rmw_topic_endpoint_info_t * topic_endpoint_info,
+  const rosidl_type_hash_t * type_hash);
+
 /// Set the node name in the given topic endpoint info data structure.
 /**
- * This functions allocates memory and copies the value of the `node_name`
- * argument to set the data structure `node_name` member.
+ * Allocates memory and copies the value of the `node_name`
+ * argument to set the data structure's `node_name` member.
  *
  * <hr>
  * Attribute          | Adherence
@@ -180,8 +218,8 @@ rmw_topic_endpoint_info_set_node_name(
 
 /// Set the node namespace in the given topic endpoint info data structure.
 /**
- * This functions allocates memory and copies the value of the `node_namespace`
- * argument to set the data structure `node_namespace` member.
+ * Allocates memory and copies the value of the `node_namespace`
+ * argument to set the data structure's `node_namespace` member.
  *
  * <hr>
  * Attribute          | Adherence
@@ -223,7 +261,7 @@ rmw_topic_endpoint_info_set_node_namespace(
 
 /// Set the endpoint type in the given topic endpoint info data structure.
 /**
- * This functions assigns the value of the `type` argument to the data structure
+ * Assigns the value of the `type` argument to the data structure's
  * `endpoint_type` member.
  *
  * <hr>
@@ -256,7 +294,7 @@ rmw_topic_endpoint_info_set_endpoint_type(
 
 /// Set the endpoint gid in the given topic endpoint info data structure.
 /**
- * This functions copies the value of the `gid` argument to the data structure
+ * Copies the value of the `gid` argument to the data structure's
  * `endpoint_gid` member.
  *
  * <hr>
@@ -293,7 +331,7 @@ rmw_topic_endpoint_info_set_gid(
 
 /// Set the endpoint QoS profile in the given topic endpoint info data structure.
 /**
- * This functions assigns the value of the `qos_profile` argument to the data structure
+ * Assigns the value of the `qos_profile` argument to the data structure's
  * `qos_profile` member.
  *
  * <hr>

rmw/src/topic_endpoint_info.c

@@ -149,6 +149,18 @@ rmw_topic_endpoint_info_set_topic_type(
   return _rmw_topic_endpoint_info_copy_str(&topic_endpoint_info->topic_type, topic_type, allocator);
 }
 
+rmw_ret_t
+rmw_topic_endpoint_info_set_topic_type_hash(
+  rmw_topic_endpoint_info_t * topic_endpoint_info,
+  const rosidl_type_hash_t * type_hash)
+{
+  RCUTILS_CAN_RETURN_WITH_ERROR_OF(RMW_RET_INVALID_ARGUMENT);
+  RCUTILS_CHECK_ARGUMENT_FOR_NULL(topic_endpoint_info, RMW_RET_INVALID_ARGUMENT);
+  RCUTILS_CHECK_ARGUMENT_FOR_NULL(type_hash, RMW_RET_INVALID_ARGUMENT);
+  topic_endpoint_info->topic_type_hash = *type_hash;
+  return RMW_RET_OK;
+}
+
 rmw_ret_t
 rmw_topic_endpoint_info_set_node_name(
   rmw_topic_endpoint_info_t * topic_endpoint_info,

rmw/test/test_topic_endpoint_info.cpp

@@ -58,6 +58,32 @@ TEST(test_topic_endpoint_info, set_topic_type) {
     "test_topic_type") << "Topic Type value is not as expected";
 }
 
+TEST(test_topic_endpoint_info, set_topic_type_hash) {
+  rmw_topic_endpoint_info_t topic_endpoint_info = rmw_get_zero_initialized_topic_endpoint_info();
+  rosidl_type_hash_t type_hash = rosidl_get_zero_initialized_type_hash();
+  type_hash.version = 22;
+  for (uint8_t i = 0; i < ROSIDL_TYPE_HASH_SIZE; i++) {
+    type_hash.value[i] = i;
+  }
+
+  rmw_ret_t ret = rmw_topic_endpoint_info_set_topic_type_hash(nullptr, &type_hash);
+  EXPECT_EQ(ret, RMW_RET_INVALID_ARGUMENT) <<
+    "Expected invalid argument for null topic_endpoint_info";
+  rmw_reset_error();
+
+  ret = rmw_topic_endpoint_info_set_topic_type_hash(&topic_endpoint_info, nullptr);
+  EXPECT_EQ(ret, RMW_RET_INVALID_ARGUMENT) << "Expected invalid argument for null type_hash";
+  rmw_reset_error();
+
+  ret = rmw_topic_endpoint_info_set_topic_type_hash(&topic_endpoint_info, &type_hash);
+  EXPECT_EQ(ret, RMW_RET_OK) << "Expected OK for valid arguments";
+
+  EXPECT_EQ(topic_endpoint_info.topic_type_hash.version, 22);
+  for (size_t i = 0; i < ROSIDL_TYPE_HASH_SIZE; i++) {
+    EXPECT_EQ(i, topic_endpoint_info.topic_type_hash.value[i]);
+  }
+}
+
 TEST(test_topic_endpoint_info, set_node_name) {
   rmw_topic_endpoint_info_t topic_endpoint_info = rmw_get_zero_initialized_topic_endpoint_info();
   rcutils_allocator_t allocator = rcutils_get_default_allocator();