I'm trying to build my project that uses boost beast library with cmake. When I use only boost asio library everything builds okay. But when I add boost/beast/http.hpp header when cmake gives a huge amount of errors.
CMake file:
cmake_minimum_required(VERSION 3.10)
project(ConsoleChat.Server)
set(Boost_USE_STATIC_LIBS ON)
set(Boost_USE_MULTITHREADED ON)
set(Boost_USE_STATIC_RUNTIME OFF)
find_package(Boost 1.75.0 REQUIRED COMPONENTS system filesystem)
add_definitions(-DBOOST_ERROR_CODE_HEADER_ONLY)
include_directories(${Boost_INCLUDE_DIRS})
link_directories(${Boost_LIBRARY_DIRS})
add_executable(ConsoleChat.Server main.cpp)
target_link_libraries(ConsoleChat.Server ${Boost_LIBRARIES})
Code file:
#include <cstdlib>
#include <memory>
#include <thread>
#include <iostream>
#include <string>
#include <boost/asio.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <boost/beast/version.hpp>
#include <boost/beast/http.hpp>
namespace net = boost::asio;
namespace beast = boost::beast;
namespace http = beast::http;
using tcp = boost::asio::ip::tcp;
int main(int argc, char* argv[])
{
try
{
if (argc != 3)
{
std::cout <<
"Usage: websocket-chat-multi <address> <port>\n" <<
"Example:\n" <<
" websocket-chat-server 0.0.0.0 8080\n";
return EXIT_FAILURE;
}
auto const address = net::ip::address::from_string(argv[1]);//net::ip::make_address(argv[1]);
auto const port = static_cast<unsigned short>(std::atoi(argv[2]));
net::io_service ios{1};
tcp::acceptor acceptor{ios, {address, port}};
for (;;)
{
tcp::socket socket{ios};
acceptor.accept(socket);
}
}
catch(const std::exception& e)
{
std::cout << e.what() << '\n';
}
}
Example of error:
In file included from /usr/local/include/boost/beast/core/buffer_traits.hpp:14,
from /usr/local/include/boost/beast/http/basic_dynamic_body.hpp:14,
from /usr/local/include/boost/beast/http.hpp:15,
from /home/kudryavii/projects/ConsoleChat/ConsoleChat.Server/main.cpp:10:
/usr/local/include/boost/beast/core/detail/buffer_traits.hpp:66:18: error: ‘is_const_buffer_sequence’ is not a member of ‘boost::beast::net’
66 | net::is_const_buffer_sequence<B>::value>::type>
| ^~~~~~~~~~~~~~~~~~~~~~~~
/usr/local/include/boost/beast/core/detail/buffer_traits.hpp:66:18: error: ‘is_const_buffer_sequence’ is not a member of ‘boost::beast::net’
I tried to add all boost libraries to find package section but this didn't help.
Yup. The preprocessed source confirms that the first mention of is_const_buffer_sequence is from line 116485 (eek), which is attributed to
# 49 "/usr/local/include/boost/beast/core/detail/buffer_traits.hpp" 3
from line 116467. On my system, that's not the first mention, because (obviously?) the declaration in boost_1_75_0/boost/asio/buffer.hpp comes before:
# 2422 "/home/sehe/custom/boost_1_75_0/boost/asio/buffer.hpp" 2 3 4
The include tree for it checks out as¹
/usr/include/boost/asio.hpp -->
/usr/include/boost/asio/basic_datagram_socket.hpp -->
/usr/include/boost/asio/datagram_socket_service.hpp -->
/usr/include/boost/asio/detail/null_socket_service.hpp -->
/usr/include/boost/asio/buffer.hpp
So, let's see if we can trace the similar path for your preprocessed source.
Reducing all the line directives (by stripping actual line numbers, and eliminating subsequent duplicates) I see the expected trail. However, then I spot differences:
# 124 "/usr/local/include/boost/asio/buffer.hpp" 3
private:
friend void* boost::asio::detail::buffer_cast_helper(
const mutable_buffer& b);
friend std::size_t boost::asio::detail::buffer_size_helper(
const mutable_buffer& b);
void* data_;
std::size_t size_;
Huh? In 1.75.0 these friends don't exist: https://github.com/boostorg/asio/blob/boost-1.75.0/include/boost/asio/buffer.hpp
You clearly have something else than Boost 1.75.0 installed there - which is funny because CMake's FindPackage should have complained? Anyways, spelunking some more:
git grep -l is_const_buffer_sequence boost-1.{60..75}.0 | grep buffer.hpp
boost-1.66.0:include/boost/asio/buffer.hpp
boost-1.67.0:include/boost/asio/buffer.hpp
boost-1.68.0:include/boost/asio/buffer.hpp
boost-1.69.0:include/boost/asio/buffer.hpp
boost-1.70.0:include/boost/asio/buffer.hpp
boost-1.71.0:include/boost/asio/buffer.hpp
boost-1.72.0:include/boost/asio/buffer.hpp
boost-1.73.0:include/boost/asio/buffer.hpp
boost-1.74.0:include/boost/asio/buffer.hpp
boost-1.75.0:include/boost/asio/buffer.hpp
And maybe also find out when the friend got deleted:
git grep -l friend boost-1.{60..75}.0 | grep buffer.hpp
boost-1.60.0:include/boost/asio/buffer.hpp
boost-1.61.0:include/boost/asio/buffer.hpp
boost-1.62.0:include/boost/asio/buffer.hpp
boost-1.63.0:include/boost/asio/buffer.hpp
boost-1.64.0:include/boost/asio/buffer.hpp
boost-1.65.0:include/boost/asio/buffer.hpp
Right at the same moment. Looks like we can pinpoint an upper-bound to your boost asio header:
git log -Sfriend include/boost/asio/buffer.hpp
commit b60e92b13ef68dfbb9af180d76eae41d22e19356
Author: Christopher Kohlhoff <[email protected]>
Date: Mon Oct 23 14:27:36 2017 +1100
Initial merge of Networking TS compatibility.
Merged from chriskohlhoff/asio master branch as of commit
4a4d28b0d24c53236e229bd1b5f378c9964b1ebb.
That's the same commit that introduced the is_const_buffer_sequence. Git confirms that your Asio version is definitely boost 1.65.0 or older²:
git tag --contains b60e92b13ef68dfbb9af180d76eae41d22e19356
boost-1.66.0
boost-1.67.0
boost-1.68.0
boost-1.69.0
boost-1.69.0-beta1
boost-1.70.0
boost-1.70.0.beta1
boost-1.71.0
boost-1.71.0.beta1
boost-1.72.0
boost-1.72.0.beta1
boost-1.73.0
boost-1.73.0.beta1
boost-1.74.0
boost-1.74.0.beta1
boost-1.75.0
boost-1.75.0.beta1
Now the wild thing is: Boost Beast didn't exist until Boost 1.66.0
In short, your install is broken. Firstly, you have an old Asio with newer Beast headers. Secondly, it's installed in such a way that CMake apparently detects it as a valid Boost installation satisfying 1.75.0 required.
¹ (this is not 100% full fidelity as I checked using vim's :check! command, which doesn't use libclang or anything options/preprocessor aware)
² Of course it will be much easier for you to just look in /usr/include/boost/version.hpp or print the value of BOOST_LIB_VERSION:
std::cout << BOOST_LIB_VERSION << "\n";