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/*
* sighandler.c
*
* Copyright (c) 2015 Pacman Development Team <pacman-dev@archlinux.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <errno.h>
#include <signal.h>
#include <unistd.h>
#include <alpm.h>
#include "conf.h"
#include "sighandler.h"
#include "util.h"
/** Write function that correctly handles EINTR.
*/
static ssize_t xwrite(int fd, const void *buf, size_t count)
{
ssize_t ret;
do {
ret = write(fd, buf, count);
} while(ret == -1 && errno == EINTR);
return ret;
}
/** Catches thrown signals. Performs necessary cleanup to ensure database is
* in a consistent state.
* @param signum the thrown signal
*/
static void handler(int signum)
{
if(signum == SIGSEGV) {
const char msg[] = "\nerror: segmentation fault\n"
"Please submit a full bug report with --debug if appropriate.\n";
xwrite(STDERR_FILENO, msg, ARRAYSIZE(msg) - 1);
exit(signum);
} else if(signum == SIGINT || signum == SIGHUP) {
if(signum == SIGINT) {
const char msg[] = "\nInterrupt signal received\n";
xwrite(STDERR_FILENO, msg, ARRAYSIZE(msg) - 1);
} else {
const char msg[] = "\nHangup signal received\n";
xwrite(STDERR_FILENO, msg, ARRAYSIZE(msg) - 1);
}
if(alpm_trans_interrupt(config->handle) == 0) {
/* a transaction is being interrupted, don't exit pacman yet. */
return;
}
} else if(signum == SIGWINCH) {
columns_cache_reset();
return;
}
/* SIGINT/SIGHUP: no committing transaction, release it now and then exit pacman */
alpm_unlock(config->handle);
/* output a newline to be sure we clear any line we may be on */
xwrite(STDOUT_FILENO, "\n", 1);
_Exit(128 + signum);
}
void install_signal_handlers(void)
{
struct sigaction new_action;
const int signals[] = { SIGHUP, SIGINT, SIGSEGV, SIGWINCH };
size_t i;
/* Set signal handlers */
/* Set up the structure to specify the new action. */
new_action.sa_handler = handler;
sigemptyset(&new_action.sa_mask);
new_action.sa_flags = SA_RESTART;
/* assign our handler to any signals we care about */
for(i = 0; i < ARRAYSIZE(signals); i++) {
sigaction(signals[i], &new_action, NULL);
}
}
/* vim: set noet: */
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