/***
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This file is part of libdaemon.
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Copyright 2003-2008 Lennart Poettering
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Permission is hereby granted, free of charge, to any person obtaining a copy
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of this software and associated documentation files (the "Software"), to deal
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in the Software without restriction, including without limitation the rights
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to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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copies of the Software, and to permit persons to whom the Software is
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furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in
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all copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.
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***/
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif
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#include <fcntl.h>
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#include <unistd.h>
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#include <errno.h>
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#include <string.h>
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#include <stdarg.h>
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#include <signal.h>
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#include "dsignal.h"
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#include "dlog.h"
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#include "dnonblock.h"
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static int _signal_pipe[2] = { -1, -1 };
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static void _sigfunc(int s) {
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int saved_errno = errno;
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write(_signal_pipe[1], &s, sizeof(s));
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errno = saved_errno;
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}
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static int _init(void) {
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if (_signal_pipe[0] < 0 || _signal_pipe[1] < 0) {
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if (pipe(_signal_pipe) < 0) {
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daemon_log(LOG_ERR, "pipe(): %s", strerror(errno));
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return -1;
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}
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if (daemon_nonblock(_signal_pipe[0], 1) < 0 || daemon_nonblock(_signal_pipe[1], 1) < 0) {
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daemon_signal_done();
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return -1;
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}
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}
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return 0;
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}
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int daemon_signal_install(int s){
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sigset_t ss;
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struct sigaction sa;
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if (_init() < 0)
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return -1;
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if (sigemptyset(&ss) < 0) {
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daemon_log(LOG_ERR, "sigemptyset(): %s", strerror(errno));
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return -1;
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}
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if (sigaddset(&ss, s) < 0) {
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daemon_log(LOG_ERR, "sigaddset(): %s", strerror(errno));
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return -1;
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}
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if (sigprocmask(SIG_UNBLOCK, &ss, NULL) < 0) {
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daemon_log(LOG_ERR, "sigprocmask(): %s", strerror(errno));
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return -1;
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}
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memset(&sa, 0, sizeof(sa));
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sa.sa_handler = _sigfunc;
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sigemptyset(&sa.sa_mask);
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sa.sa_flags = SA_RESTART;
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if (sigaction(s, &sa, NULL) < 0) {
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daemon_log(LOG_ERR, "sigaction(%s, ...) failed: %s", strsignal(s), strerror(errno));
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return -1;
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}
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return 0;
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}
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int daemon_signal_init(int s, ...) {
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int sig, r = 0;
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va_list ap;
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if (_init() < 0)
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return -1;
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va_start(ap, s);
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sig = s;
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while (sig > 0) {
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if ((r = daemon_signal_install(sig)) < 0)
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break;
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sig = va_arg(ap, int);
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}
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va_end(ap);
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return r;
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}
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void daemon_signal_done(void) {
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int saved_errno = errno;
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if (_signal_pipe[0] != -1)
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close(_signal_pipe[0]);
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if (_signal_pipe[1] != -1)
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close(_signal_pipe[1]);
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_signal_pipe[0] = _signal_pipe[1] = -1;
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errno = saved_errno;
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}
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int daemon_signal_next(void) {
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int s;
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ssize_t r;
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if ((r = read(_signal_pipe[0], &s, sizeof(s))) == sizeof(s))
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return s;
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if (r < 0) {
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if (errno == EAGAIN)
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return 0;
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else {
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daemon_log(LOG_ERR, "read(signal_pipe[0], ...): %s", strerror(errno));
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return -1;
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}
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}
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daemon_log(LOG_ERR, "Short read() on signal pipe.");
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return -1;
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}
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int daemon_signal_fd(void) {
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return _signal_pipe[0];
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}
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