c_api.h

Go to the documentation of this file.

#pragma once
 
// SPDX-License-Identifier: BSD-3-Clause
// SPDX-FileCopyrightText: Czech Technical University in Prague
 
#include <string>
#include <vector>
 
#include <ros/message_traits.h>
#include <ros/serialization.h>
 
#include <cras_cpp_common/message_utils.hpp>
 
namespace cras
{
 
typedef void* (*allocator_t)(size_t);
 
char* outputString(allocator_t allocator, const char* string, size_t length);
 
char* outputString(allocator_t allocator, const std::string& string);
 
uint8_t* outputByteBuffer(allocator_t allocator, const uint8_t* bytes, size_t length);
 
uint8_t* outputByteBuffer(allocator_t allocator, const std::vector<uint8_t>& bytes);
 
template<typename Message, typename Enable = ::std::enable_if_t<::ros::message_traits::IsMessage<Message>::value>>
uint8_t* outputRosMessage(allocator_t allocator, const Message& msg)
{
  // This code does almost the same as ros::serialization::serializeMessage(), but it directly uses the allocated
  // buffer instead of creating its own one and then copying.
 
  const auto len = static_cast<uint32_t>(::ros::serialization::serializationLength(msg));
  const auto buf = static_cast<uint8_t*>(allocator(len));
 
  ::ros::serialization::OStream s(buf, len);
  ::ros::serialization::serialize(s, msg);
 
  return buf;
}
 
}