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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/cpp03/fork/daemon.cpp | |
parent | 24154bc1f00790f344120b3a85175d6f616c5ad0 (diff) |
3rdparty/asio: Updated to 1.30.2
Diffstat (limited to '3rdparty/asio/src/examples/cpp03/fork/daemon.cpp')
-rw-r--r-- | 3rdparty/asio/src/examples/cpp03/fork/daemon.cpp | 190 |
1 files changed, 0 insertions, 190 deletions
diff --git a/3rdparty/asio/src/examples/cpp03/fork/daemon.cpp b/3rdparty/asio/src/examples/cpp03/fork/daemon.cpp deleted file mode 100644 index ae00d3d6aff..00000000000 --- a/3rdparty/asio/src/examples/cpp03/fork/daemon.cpp +++ /dev/null @@ -1,190 +0,0 @@ -// -// daemon.cpp -// ~~~~~~~~~~ -// -// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com) -// -// 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) -// - -#include <asio/io_context.hpp> -#include <asio/ip/udp.hpp> -#include <asio/signal_set.hpp> -#include <boost/array.hpp> -#include <boost/bind/bind.hpp> -#include <ctime> -#include <iostream> -#include <syslog.h> -#include <unistd.h> - -using asio::ip::udp; - -class udp_daytime_server -{ -public: - udp_daytime_server(asio::io_context& io_context) - : socket_(io_context, udp::endpoint(udp::v4(), 13)) - { - start_receive(); - } - -private: - void start_receive() - { - socket_.async_receive_from( - asio::buffer(recv_buffer_), remote_endpoint_, - boost::bind(&udp_daytime_server::handle_receive, - this, boost::placeholders::_1)); - } - - void handle_receive(const asio::error_code& ec) - { - if (!ec) - { - using namespace std; // For time_t, time and ctime; - time_t now = time(0); - std::string message = ctime(&now); - - asio::error_code ignored_ec; - socket_.send_to(asio::buffer(message), - remote_endpoint_, 0, ignored_ec); - } - - start_receive(); - } - - udp::socket socket_; - udp::endpoint remote_endpoint_; - boost::array<char, 1> recv_buffer_; -}; - -int main() -{ - try - { - asio::io_context io_context; - - // Initialise the server before becoming a daemon. If the process is - // started from a shell, this means any errors will be reported back to the - // user. - udp_daytime_server server(io_context); - - // Register signal handlers so that the daemon may be shut down. You may - // also want to register for other signals, such as SIGHUP to trigger a - // re-read of a configuration file. - asio::signal_set signals(io_context, SIGINT, SIGTERM); - signals.async_wait( - boost::bind(&asio::io_context::stop, &io_context)); - - // Inform the io_context that we are about to become a daemon. The - // io_context cleans up any internal resources, such as threads, that may - // interfere with forking. - io_context.notify_fork(asio::io_context::fork_prepare); - - // Fork the process and have the parent exit. If the process was started - // from a shell, this returns control to the user. Forking a new process is - // also a prerequisite for the subsequent call to setsid(). - if (pid_t pid = fork()) - { - if (pid > 0) - { - // We're in the parent process and need to exit. - // - // When the exit() function is used, the program terminates without - // invoking local variables' destructors. Only global variables are - // destroyed. As the io_context object is a local variable, this means - // we do not have to call: - // - // io_context.notify_fork(asio::io_context::fork_parent); - // - // However, this line should be added before each call to exit() if - // using a global io_context object. An additional call: - // - // io_context.notify_fork(asio::io_context::fork_prepare); - // - // should also precede the second fork(). - exit(0); - } - else - { - syslog(LOG_ERR | LOG_USER, "First fork failed: %m"); - return 1; - } - } - - // Make the process a new session leader. This detaches it from the - // terminal. - setsid(); - - // A process inherits its working directory from its parent. This could be - // on a mounted filesystem, which means that the running daemon would - // prevent this filesystem from being unmounted. Changing to the root - // directory avoids this problem. - chdir("/"); - - // The file mode creation mask is also inherited from the parent process. - // We don't want to restrict the permissions on files created by the - // daemon, so the mask is cleared. - umask(0); - - // A second fork ensures the process cannot acquire a controlling terminal. - if (pid_t pid = fork()) - { - if (pid > 0) - { - exit(0); - } - else - { - syslog(LOG_ERR | LOG_USER, "Second fork failed: %m"); - return 1; - } - } - - // Close the standard streams. This decouples the daemon from the terminal - // that started it. - close(0); - close(1); - close(2); - - // We don't want the daemon to have any standard input. - if (open("/dev/null", O_RDONLY) < 0) - { - syslog(LOG_ERR | LOG_USER, "Unable to open /dev/null: %m"); - return 1; - } - - // Send standard output to a log file. - const char* output = "/tmp/asio.daemon.out"; - const int flags = O_WRONLY | O_CREAT | O_APPEND; - const mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; - if (open(output, flags, mode) < 0) - { - syslog(LOG_ERR | LOG_USER, "Unable to open output file %s: %m", output); - return 1; - } - - // Also send standard error to the same log file. - if (dup(1) < 0) - { - syslog(LOG_ERR | LOG_USER, "Unable to dup output descriptor: %m"); - return 1; - } - - // Inform the io_context that we have finished becoming a daemon. The - // io_context uses this opportunity to create any internal file descriptors - // that need to be private to the new process. - io_context.notify_fork(asio::io_context::fork_child); - - // The io_context can now be used normally. - syslog(LOG_INFO | LOG_USER, "Daemon started"); - io_context.run(); - syslog(LOG_INFO | LOG_USER, "Daemon stopped"); - } - catch (std::exception& e) - { - syslog(LOG_ERR | LOG_USER, "Exception: %s", e.what()); - std::cerr << "Exception: " << e.what() << std::endl; - } -} |