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author | 2024-04-22 08:04:58 +1000 | |
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committer | 2024-04-22 08:04:58 +1000 | |
commit | 184292b730f4236bd4840e780fdad97ee060ec84 (patch) | |
tree | 67902161a465fe92aec78ca502de07092b8cde0f /3rdparty/asio/src/examples/cpp11/local/fd_passing_stream_server.cpp | |
parent | 24154bc1f00790f344120b3a85175d6f616c5ad0 (diff) |
3rdparty/asio: Updated to 1.30.2
Diffstat (limited to '3rdparty/asio/src/examples/cpp11/local/fd_passing_stream_server.cpp')
-rw-r--r-- | 3rdparty/asio/src/examples/cpp11/local/fd_passing_stream_server.cpp | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/3rdparty/asio/src/examples/cpp11/local/fd_passing_stream_server.cpp b/3rdparty/asio/src/examples/cpp11/local/fd_passing_stream_server.cpp new file mode 100644 index 00000000000..5082185e75c --- /dev/null +++ b/3rdparty/asio/src/examples/cpp11/local/fd_passing_stream_server.cpp @@ -0,0 +1,160 @@ +// +// fd_passing_stream_server.cpp +// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +// +// Copyright (c) 2003-2024 Christopher M. Kohlhoff (chris at kohlhoff dot com) +// Copyright (c) 2021 Heiko Hund (heiko at openvpn dot net) +// +// Distributed under the Boost Software License, Version 1.0. (See accompanying +// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) +// + +// Demonstrates how to pass file descriptors between processes with Asio. +// The client sends a file name to the server. The server opens the file and +// passes the associated file descriptor back to the client. + +#include <array> +#include <cstdio> +#include <cassert> +#include <iostream> +#include <memory> +#include "asio.hpp" + +#if defined(ASIO_HAS_LOCAL_SOCKETS) + +using asio::local::stream_protocol; + +class session + : public std::enable_shared_from_this<session> +{ +public: + session(stream_protocol::socket sock) + : socket_(std::move(sock)) + { + } + + void start() + { + do_read(); + } + +private: + void do_read() + { + auto self(shared_from_this()); + socket_.async_read_some(asio::buffer(data_), + [this, self](std::error_code ec, std::size_t length) + { + if (ec) + return; + + assert(length < data_.size()); + data_[length] = 0; + do_write(data_.data()); + }); + } + + void do_write(const char* filename) + { + auto self(shared_from_this()); + socket_.async_wait(stream_protocol::socket::wait_write, + [this, self, filename](std::error_code ec) + { + if (ec) + return; + + FILE* f(::fopen(filename, "w+")); + if (!f) + return; + + struct msghdr msg = {}; + char buf[] = { 0 }; + struct iovec iov = { buf, sizeof(buf) }; + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + + union + { + struct cmsghdr align; + char buf[CMSG_SPACE(sizeof(int))]; + } cmsgu; + msg.msg_control = cmsgu.buf; + msg.msg_controllen = sizeof(cmsgu.buf); + + struct cmsghdr* cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_len = CMSG_LEN(sizeof(int)); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + int fd = ::fileno(f); + std::memcpy(CMSG_DATA(cmsg), &fd, sizeof(int)); + + ssize_t s(::sendmsg(socket_.native_handle(), &msg, 0)); + ::fclose(f); + if (s != -1) + do_read(); + }); + } + + // The socket used to communicate with the client. + stream_protocol::socket socket_; + + // Buffer used to store data received from the client. + std::array<char, 1024> data_; +}; + +class server +{ +public: + server(asio::io_context& io_context, const std::string& file) + : acceptor_(io_context, stream_protocol::endpoint(file)) + { + do_accept(); + } + +private: + void do_accept() + { + acceptor_.async_accept( + [this](std::error_code ec, stream_protocol::socket socket) + { + if (!ec) + { + std::make_shared<session>(std::move(socket))->start(); + } + + do_accept(); + }); + } + + stream_protocol::acceptor acceptor_; +}; + +int main(int argc, char* argv[]) +{ + try + { + if (argc != 2) + { + std::cerr << "Usage: fd_passing_stream_server <socketfile>\n"; + std::cerr << "*** WARNING: existing file is removed ***\n"; + return 1; + } + + asio::io_context io_context; + + std::remove(argv[1]); + server s(io_context, argv[1]); + + io_context.run(); + } + catch (std::exception& e) + { + std::cerr << "Exception: " << e.what() << "\n"; + } + + return 0; +} + +#else // defined(ASIO_HAS_LOCAL_SOCKETS) +# error Local sockets not available on this platform. +#endif // defined(ASIO_HAS_LOCAL_SOCKETS) |