node.c

// Copyright 2015 Open Source Robotics Foundation, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
 
#include "rcl/node.h"
 
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
#include "rcl/arguments.h"
#include "rcl/error_handling.h"
#include "rcl/init_options.h"
#include "rcl/logging.h"
#include "rcl/logging_rosout.h"
#include "rcl/node_type_cache.h"
#include "rcl/rcl.h"
#include "rcl/remap.h"
#include "rcl/security.h"
 
#include "rcutils/env.h"
#include "rcutils/filesystem.h"
#include "rcutils/find.h"
#include "rcutils/format_string.h"
#include "rcutils/logging_macros.h"
#include "rcutils/macros.h"
#include "rcutils/repl_str.h"
#include "rcutils/snprintf.h"
#include "rcutils/strdup.h"
#include "rcutils/types/hash_map.h"
 
#include "rmw/error_handling.h"
#include "rmw/security_options.h"
#include "rmw/rmw.h"
#include "rmw/validate_namespace.h"
#include "rmw/validate_node_name.h"
#include "rosidl_runtime_c/string_functions.h"
#include "rosidl_runtime_c/type_description/type_description__functions.h"
#include "rosidl_runtime_c/type_description/type_source__functions.h"
#include "tracetools/tracetools.h"
#include "type_description_interfaces/srv/get_type_description.h"
 
#include "./context_impl.h"
#include "./node_impl.h"
 
const char * const RCL_DISABLE_LOANED_MESSAGES_ENV_VAR = "ROS_DISABLE_LOANED_MESSAGES";
 
 
const char * rcl_create_node_logger_name(
  const char * node_name,
  const char * node_namespace,
  const rcl_allocator_t * allocator)
{
  // If the namespace is the root namespace ("/"), the logger name is just the node name.
  if (strlen(node_namespace) == 1) {
    return rcutils_strdup(node_name, *allocator);
  }
 
  // Convert the forward slashes in the namespace to the separator used for logger names.
  // The input namespace has already been expanded and therefore will always be absolute,
  // i.e. it will start with a forward slash, which we want to ignore.
  const char * ns_with_separators = rcutils_repl_str(
    node_namespace + 1,  // Ignore the leading forward slash.
    "/", RCUTILS_LOGGING_SEPARATOR_STRING,
    allocator);
  if (NULL == ns_with_separators) {
    return NULL;
  }
 
  // Join the namespace and node name to create the logger name.
  char * node_logger_name = rcutils_format_string(
    *allocator, "%s%s%s", ns_with_separators, RCUTILS_LOGGING_SEPARATOR_STRING, node_name);
  allocator->deallocate((char *)ns_with_separators, allocator->state);
  return node_logger_name;
}
 
rcl_node_t
rcl_get_zero_initialized_node(void)
{
  // All members are initialized to 0 or NULL by C99 6.7.8/10.
  static rcl_node_t null_node;
  return null_node;
}
 
rcl_ret_t
rcl_node_init(
  rcl_node_t * node,
  const char * name,
  const char * namespace_,
  rcl_context_t * context,
  const rcl_node_options_t * options)
{
  const rmw_guard_condition_t * rmw_graph_guard_condition = NULL;
  rcl_guard_condition_options_t graph_guard_condition_options =
    rcl_guard_condition_get_default_options();
  rcl_ret_t ret;
  rcl_ret_t fail_ret = RCL_RET_ERROR;
  char * remapped_node_name = NULL;
  const char * local_namespace_ = NULL;
 
  // Check options and allocator first, so allocator can be used for errors.
  RCL_CHECK_ARGUMENT_FOR_NULL(options, RCL_RET_INVALID_ARGUMENT);
  const rcl_allocator_t * allocator = &options->allocator;
  RCL_CHECK_ALLOCATOR_WITH_MSG(allocator, "invalid allocator", return RCL_RET_INVALID_ARGUMENT);
 
  RCL_CHECK_ARGUMENT_FOR_NULL(name, RCL_RET_INVALID_ARGUMENT);
  RCL_CHECK_ARGUMENT_FOR_NULL(namespace_, RCL_RET_INVALID_ARGUMENT);
  RCL_CHECK_ARGUMENT_FOR_NULL(node, RCL_RET_INVALID_ARGUMENT);
  RCUTILS_LOG_DEBUG_NAMED(
    ROS_PACKAGE_NAME, "Initializing node '%s' in namespace '%s'", name, namespace_);
  if (node->impl) {
    RCL_SET_ERROR_MSG("node already initialized, or struct memory was unintialized");
    return RCL_RET_ALREADY_INIT;
  }
  // Make sure rcl has been initialized.
  RCL_CHECK_FOR_NULL_WITH_MSG(
    context, "given context in options is NULL", return RCL_RET_INVALID_ARGUMENT);
  if (!rcl_context_is_valid(context)) {
    RCL_SET_ERROR_MSG(
      "the given context is not valid, "
      "either rcl_init() was not called or rcl_shutdown() was called.");
    return RCL_RET_NOT_INIT;
  }
  // Make sure the node name is valid before allocating memory.
  int validation_result = 0;
  ret = rmw_validate_node_name(name, &validation_result, NULL);
  if (ret != RMW_RET_OK) {
    RCL_SET_ERROR_MSG(rmw_get_error_string().str);
    return ret;
  }
  if (validation_result != RMW_NODE_NAME_VALID) {
    const char * msg = rmw_node_name_validation_result_string(validation_result);
    RCL_SET_ERROR_MSG(msg);
    return RCL_RET_NODE_INVALID_NAME;
  }
 
  // Process the namespace.
  if (namespace_[0] == '\0') {
    // If the namespace is just an empty string, replace with "/"
    local_namespace_ = rcutils_strdup("/", *allocator);
  } else if (namespace_[0] == '/') {
    local_namespace_ = rcutils_strdup(namespace_, *allocator);
  } else {
    // If the namespace does not start with a /, add one.
    local_namespace_ = rcutils_format_string(*allocator, "/%s", namespace_);
  }
  RCL_CHECK_FOR_NULL_WITH_MSG(
    local_namespace_,
    "failed to format node namespace string",
    return RCL_RET_BAD_ALLOC);
 
  // Make sure the node namespace is valid.
  validation_result = 0;
  ret = rmw_validate_namespace(local_namespace_, &validation_result, NULL);
  if (ret != RMW_RET_OK) {
    RCL_SET_ERROR_MSG(rmw_get_error_string().str);
    goto fail;
  }
  if (validation_result != RMW_NAMESPACE_VALID) {
    const char * msg = rmw_namespace_validation_result_string(validation_result);
    RCL_SET_ERROR_MSG_WITH_FORMAT_STRING("%s, result: %d", msg, validation_result);
 
    ret = RCL_RET_NODE_INVALID_NAMESPACE;
    goto fail;
  }
 
  // Allocate space for the implementation struct.
  node->impl = (rcl_node_impl_t *)allocator->zero_allocate(
    1, sizeof(rcl_node_impl_t), allocator->state);
  RCL_CHECK_FOR_NULL_WITH_MSG(
    node->impl, "allocating memory failed", ret = RCL_RET_BAD_ALLOC; goto fail);
  node->impl->options = rcl_node_get_default_options();
  node->impl->registered_types_by_type_hash = rcutils_get_zero_initialized_hash_map();
  node->context = context;
  // Initialize node impl.
  ret = rcl_node_options_copy(options, &(node->impl->options));
  if (RCL_RET_OK != ret) {
    goto fail;
  }
 
  // Remap the node name and namespace if remap rules are given
  rcl_arguments_t * global_args = NULL;
  if (node->impl->options.use_global_arguments) {
    global_args = &(node->context->global_arguments);
  }
  ret = rcl_remap_node_name(
    &(node->impl->options.arguments), global_args, name, *allocator,
    &remapped_node_name);
  if (RCL_RET_OK != ret) {
    goto fail;
  }
  if (NULL != remapped_node_name) {
    name = remapped_node_name;
  }
 
  char * remapped_namespace = NULL;
  ret = rcl_remap_node_namespace(
    &(node->impl->options.arguments), global_args, name,
    *allocator, &remapped_namespace);
  if (RCL_RET_OK != ret) {
    goto fail;
  }
  if (NULL != remapped_namespace) {
    allocator->deallocate((char *)local_namespace_, allocator->state);
    local_namespace_ = remapped_namespace;
  }
 
  // compute fully qualfied name of the node.
  if ('/' == local_namespace_[strlen(local_namespace_) - 1]) {
    node->impl->fq_name = rcutils_format_string(*allocator, "%s%s", local_namespace_, name);
  } else {
    node->impl->fq_name = rcutils_format_string(*allocator, "%s/%s", local_namespace_, name);
  }
  RCL_CHECK_FOR_NULL_WITH_MSG(
    node->impl->fq_name, "creating fully qualified name failed",
    ret = RCL_RET_BAD_ALLOC; goto fail);
 
  // node logger name
  node->impl->logger_name = rcl_create_node_logger_name(name, local_namespace_, allocator);
  RCL_CHECK_FOR_NULL_WITH_MSG(
    node->impl->logger_name, "creating logger name failed", ret = RCL_RET_ERROR; goto fail);
 
  RCUTILS_LOG_DEBUG_NAMED(
    ROS_PACKAGE_NAME, "Using domain ID of '%zu'", context->impl->rmw_context.actual_domain_id);
 
  node->impl->rmw_node_handle = rmw_create_node(
    &(node->context->impl->rmw_context),
    name, local_namespace_);
  if (NULL == node->impl->rmw_node_handle) {
    // Preserve the error set by rmw_create_node rather than overwriting it.
    RCL_EXPECT_ERROR_IS_SET(RCL_RET_ERROR);
    ret = RCL_RET_ERROR;
    goto fail;
  }
 
  // graph guard condition
  rmw_graph_guard_condition = rmw_node_get_graph_guard_condition(node->impl->rmw_node_handle);
  if (NULL == rmw_graph_guard_condition) {
    // Preserve the error set by rmw_node_get_graph_guard_condition.
    RCL_EXPECT_ERROR_IS_SET(RCL_RET_ERROR);
    ret = RCL_RET_ERROR;
    goto fail;
  }
 
  node->impl->graph_guard_condition = (rcl_guard_condition_t *)allocator->allocate(
    sizeof(rcl_guard_condition_t), allocator->state);
  RCL_CHECK_FOR_NULL_WITH_MSG(
    node->impl->graph_guard_condition, "allocating memory failed",
    ret = RCL_RET_BAD_ALLOC; goto fail);
  *node->impl->graph_guard_condition = rcl_get_zero_initialized_guard_condition();
  graph_guard_condition_options.allocator = *allocator;
  ret = rcl_guard_condition_init_from_rmw(
    node->impl->graph_guard_condition,
    rmw_graph_guard_condition,
    context,
    graph_guard_condition_options);
  if (ret != RCL_RET_OK) {
    // error message already set
    goto fail;
  }
 
  // To capture all types from builtin topics and services, the type cache needs to be initialized
  // before any publishers/subscriptions/services/etc can be created
  ret = rcl_node_type_cache_init(node);
  if (ret != RCL_RET_OK) {
    goto fail;
  }
 
  RCUTILS_LOG_DEBUG_NAMED(ROS_PACKAGE_NAME, "Node initialized");
  TRACETOOLS_TRACEPOINT(
    rcl_node_init,
    (const void *)node,
    (const void *)rcl_node_get_rmw_handle(node),
    rcl_node_get_name(node),
    rcl_node_get_namespace(node));
 
  allocator->deallocate(remapped_node_name, allocator->state);
  allocator->deallocate((char *)local_namespace_, allocator->state);
 
  return RCL_RET_OK;
 
fail:
  if (node->impl) {
    if (NULL != node->impl->registered_types_by_type_hash.impl) {
      fail_ret = rcl_node_type_cache_fini(node);
      RCUTILS_LOG_ERROR_EXPRESSION_NAMED(
        (fail_ret != RCL_RET_OK),
        ROS_PACKAGE_NAME, "Failed to fini type cache for node: %s", rcl_get_error_string().str);
    }
 
    if (node->impl->graph_guard_condition) {
      fail_ret = rcl_guard_condition_fini(node->impl->graph_guard_condition);
      RCUTILS_LOG_ERROR_EXPRESSION_NAMED(
        fail_ret != RCL_RET_OK, ROS_PACKAGE_NAME,
        "failed to fini guard condition in error recovery: %s", rcl_get_error_string().str);
 
      allocator->deallocate(node->impl->graph_guard_condition, allocator->state);
    }
 
    if (node->impl->rmw_node_handle) {
      fail_ret = rmw_destroy_node(node->impl->rmw_node_handle);
      RCUTILS_LOG_ERROR_EXPRESSION_NAMED(
        fail_ret != RMW_RET_OK, ROS_PACKAGE_NAME,
        "failed to fini rmw node in error recovery: %s", rmw_get_error_string().str);
    }
 
    allocator->deallocate((char *)node->impl->logger_name, allocator->state);
 
    allocator->deallocate((char *)node->impl->fq_name, allocator->state);
 
    fail_ret = rcl_node_options_fini(&(node->impl->options));
    RCUTILS_LOG_ERROR_EXPRESSION_NAMED(
      fail_ret != RCL_RET_OK, ROS_PACKAGE_NAME,
      "failed to fini node options: %s", rcl_get_error_string().str);
 
    allocator->deallocate(node->impl, allocator->state);
  }
 
  allocator->deallocate(remapped_node_name, allocator->state);
 
  allocator->deallocate((char *)local_namespace_, allocator->state);
 
  *node = rcl_get_zero_initialized_node();
 
  return ret;
}
 
rcl_ret_t
rcl_node_fini(rcl_node_t * node)
{
  RCUTILS_LOG_DEBUG_NAMED(ROS_PACKAGE_NAME, "Finalizing node");
  RCL_CHECK_ARGUMENT_FOR_NULL(node, RCL_RET_NODE_INVALID);
  if (!node->impl) {
    // Repeat calls to fini or calling fini on a zero initialized node is ok.
    return RCL_RET_OK;
  }
  rcl_allocator_t allocator = node->impl->options.allocator;
  rcl_ret_t result = RCL_RET_OK;
  rcl_ret_t rcl_ret = RCL_RET_OK;
  rcl_ret = rcl_node_type_cache_fini(node);
  if (rcl_ret != RCL_RET_OK) {
    RCL_SET_ERROR_MSG("Unable to fini type cache for node.");
    result = RCL_RET_ERROR;
  }
  rmw_ret_t rmw_ret = rmw_destroy_node(node->impl->rmw_node_handle);
  if (rmw_ret != RMW_RET_OK) {
    RCL_SET_ERROR_MSG(rmw_get_error_string().str);
    result = RCL_RET_ERROR;
  }
  rcl_ret = rcl_guard_condition_fini(node->impl->graph_guard_condition);
  if (rcl_ret != RCL_RET_OK) {
    RCL_SET_ERROR_MSG(rmw_get_error_string().str);
    result = RCL_RET_ERROR;
  }
  allocator.deallocate(node->impl->graph_guard_condition, allocator.state);
  // assuming that allocate and deallocate are ok since they are checked in init
  allocator.deallocate((char *)node->impl->logger_name, allocator.state);
  allocator.deallocate((char *)node->impl->fq_name, allocator.state);
  if (NULL != node->impl->options.arguments.impl) {
    rcl_ret_t ret = rcl_arguments_fini(&(node->impl->options.arguments));
    if (ret != RCL_RET_OK) {
      return ret;
    }
  }
  allocator.deallocate(node->impl, allocator.state);
  node->impl = NULL;
  RCUTILS_LOG_DEBUG_NAMED(ROS_PACKAGE_NAME, "Node finalized");
  return result;
}
 
bool
rcl_node_is_valid_except_context(const rcl_node_t * node)
{
  RCL_CHECK_FOR_NULL_WITH_MSG(node, "rcl node pointer is invalid", return false);
  RCL_CHECK_FOR_NULL_WITH_MSG(node->impl, "rcl node implementation is invalid", return false);
  RCL_CHECK_FOR_NULL_WITH_MSG(
    node->impl->rmw_node_handle, "rcl node's rmw handle is invalid", return false);
  return true;
}
 
bool
rcl_node_is_valid(const rcl_node_t * node)
{
  bool result = rcl_node_is_valid_except_context(node);
  if (!result) {
    return result;
  }
  if (!rcl_context_is_valid(node->context)) {
    RCL_SET_ERROR_MSG("rcl node's context is invalid");
    return false;
  }
  return true;
}
 
const char *
rcl_node_get_name(const rcl_node_t * node)
{
  if (!rcl_node_is_valid_except_context(node)) {
    return NULL;  // error already set
  }
  return node->impl->rmw_node_handle->name;
}
 
const char *
rcl_node_get_namespace(const rcl_node_t * node)
{
  if (!rcl_node_is_valid_except_context(node)) {
    return NULL;  // error already set
  }
  return node->impl->rmw_node_handle->namespace_;
}
 
const char *
rcl_node_get_fully_qualified_name(const rcl_node_t * node)
{
  if (!rcl_node_is_valid_except_context(node)) {
    return NULL;  // error already set
  }
  return node->impl->fq_name;
}
 
const rcl_node_options_t *
rcl_node_get_options(const rcl_node_t * node)
{
  if (!rcl_node_is_valid_except_context(node)) {
    return NULL;  // error already set
  }
  return &node->impl->options;
}
 
rcl_ret_t
rcl_node_get_domain_id(const rcl_node_t * node, size_t * domain_id)
{
  if (!rcl_node_is_valid(node)) {
    return RCL_RET_NODE_INVALID;
  }
  RCL_CHECK_ARGUMENT_FOR_NULL(domain_id, RCL_RET_INVALID_ARGUMENT);
  rcl_ret_t ret = rcl_context_get_domain_id(node->context, domain_id);
  if (RCL_RET_OK != ret) {
    return ret;
  }
  return RCL_RET_OK;
}
 
rmw_node_t *
rcl_node_get_rmw_handle(const rcl_node_t * node)
{
  if (!rcl_node_is_valid_except_context(node)) {
    return NULL;  // error already set
  }
  return node->impl->rmw_node_handle;
}
 
uint64_t
rcl_node_get_rcl_instance_id(const rcl_node_t * node)
{
  if (!rcl_node_is_valid_except_context(node)) {
    return 0;  // error already set
  }
  return rcl_context_get_instance_id(node->context);
}
 
const rcl_guard_condition_t *
rcl_node_get_graph_guard_condition(const rcl_node_t * node)
{
  if (!rcl_node_is_valid_except_context(node)) {
    return NULL;  // error already set
  }
  return node->impl->graph_guard_condition;
}
 
const char *
rcl_node_get_logger_name(const rcl_node_t * node)
{
  if (!rcl_node_is_valid_except_context(node)) {
    return NULL;  // error already set
  }
  return node->impl->logger_name;
}
 
rcl_ret_t
rcl_get_disable_loaned_message(bool * disable_loaned_message)
{
  const char * env_val = NULL;
  const char * env_error_str = NULL;
 
  RCL_CHECK_ARGUMENT_FOR_NULL(disable_loaned_message, RCL_RET_INVALID_ARGUMENT);
 
  env_error_str = rcutils_get_env(RCL_DISABLE_LOANED_MESSAGES_ENV_VAR, &env_val);
  if (NULL != env_error_str) {
    RCL_SET_ERROR_MSG_WITH_FORMAT_STRING(
      "Error getting env var: '" RCUTILS_STRINGIFY(RCL_DISABLE_LOANED_MESSAGES_ENV_VAR) "': %s\n",
      env_error_str);
    return RCL_RET_ERROR;
  }
 
  *disable_loaned_message = (strcmp(env_val, "1") == 0);
  return RCL_RET_OK;
}
 
void rcl_node_type_description_service_handle_request(
  rcl_node_t * node,
  const rmw_request_id_t * request_header,
  const type_description_interfaces__srv__GetTypeDescription_Request * request,
  type_description_interfaces__srv__GetTypeDescription_Response * response)
{
  rcl_type_info_t type_info;
  RCL_CHECK_FOR_NULL_WITH_MSG(node, "invalid node handle", return;);
  RCL_CHECK_FOR_NULL_WITH_MSG(node->impl, "invalid node", return;);
  RCL_CHECK_FOR_NULL_WITH_MSG(request_header, "invalid request header", return;);
  RCL_CHECK_FOR_NULL_WITH_MSG(request, "null request pointer", return;);
  RCL_CHECK_FOR_NULL_WITH_MSG(response, "null response pointer", return;);
 
  if (!type_description_interfaces__srv__GetTypeDescription_Response__init(response)) {
    RCUTILS_LOG_ERROR_NAMED(
      ROS_PACKAGE_NAME,
      "Failed to initialize service response.");
    return;
  }
  response->successful = false;
 
  rosidl_type_hash_t type_hash;
  if (RCUTILS_RET_OK !=
    rosidl_parse_type_hash_string(request->type_hash.data, &type_hash))
  {
    RCUTILS_LOG_ERROR_NAMED(
      ROS_PACKAGE_NAME, "Failed to parse type hash '%s'",
      request->type_hash.data);
    rosidl_runtime_c__String__assign(
      &response->failure_reason,
      "Failed to parse type hash");
    return;
  }
 
  if (RCUTILS_RET_OK !=
    rcl_node_type_cache_get_type_info(node, &type_hash, &type_info))
  {
    rosidl_runtime_c__String__assign(
      &response->failure_reason,
      "Type not currently in use by this node");
    return;
  }
 
  if (!type_description_interfaces__msg__TypeDescription__copy(
      type_info.type_description, &response->type_description))
  {
    rosidl_runtime_c__String__assign(
      &response->failure_reason,
      "Failed to populate TypeDescription to response.");
    return;
  }
 
  if (request->include_type_sources) {
    if (!type_description_interfaces__msg__TypeSource__Sequence__copy(
        type_info.type_sources, &response->type_sources))
    {
      rosidl_runtime_c__String__assign(
        &response->failure_reason,
        "Failed to populate TypeSource_Sequence to response.");
      return;
    }
  }
 
  response->successful = true;
}
 
rcl_ret_t rcl_node_type_description_service_init(
  rcl_service_t * service,
  const rcl_node_t * node)
{
  RCL_CHECK_ARGUMENT_FOR_NULL(service, RCL_RET_INVALID_ARGUMENT);
  RCL_CHECK_ARGUMENT_FOR_NULL(node, RCL_RET_INVALID_ARGUMENT);
  RCL_CHECK_ARGUMENT_FOR_NULL(node->impl, RCL_RET_NODE_INVALID);
 
  if (rcl_service_is_valid(service)) {
    return RCL_RET_ALREADY_INIT;
  }
  rcl_reset_error();  // Reset the error message set by rcl_service_is_valid()
 
  char * service_name = NULL;
  const rosidl_service_type_support_t * type_support =
    ROSIDL_GET_SRV_TYPE_SUPPORT(
    type_description_interfaces, srv,
    GetTypeDescription);
  rcl_service_options_t service_ops = rcl_service_get_default_options();
  rcl_allocator_t allocator = node->context->impl->allocator;
 
  // Construct service name
  rcl_ret_t ret = rcl_node_resolve_name(
    node, "~/get_type_description",
    allocator, true, true, &service_name);
  if (RCL_RET_OK != ret) {
    RCL_SET_ERROR_MSG(
      "Failed to construct ~/get_type_description service name");
    return ret;
  }
 
  // Initialize service
  ret = rcl_service_init(
    service, node,
    type_support, service_name, &service_ops);
  allocator.deallocate(service_name, allocator.state);
 
  return ret;
}