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-rw-r--r--3rdparty/asio/src/examples/cpp03/fork/daemon.cpp189
1 files changed, 0 insertions, 189 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 06eef3d6b49..00000000000
--- a/3rdparty/asio/src/examples/cpp03/fork/daemon.cpp
+++ /dev/null
@@ -1,189 +0,0 @@
-//
-// daemon.cpp
-// ~~~~~~~~~~
-//
-// Copyright (c) 2003-2016 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.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, _1));
- }
-
- void handle_receive(const asio::error_code& ec)
- {
- if (!ec || ec == asio::error::message_size)
- {
- 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;
- }
-}