dpkg/lib/subproc.c

/*
 * libdpkg - Debian packaging suite library routines
 * subproc.c - subprocess helper routines
 *
 * Copyright © 1995 Ian Jackson <ian@chiark.greenend.org.uk>
 *
 * This 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,
 * or (at your option) any later version.
 *
 * This 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 dpkg; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <config.h>
#include <compat.h>

#include <dpkg-i18n.h>

#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <signal.h>

#include <dpkg.h>
#include <dpkg-priv.h>

static int catch_signals[] = { SIGQUIT, SIGINT };
static struct sigaction uncatch_signals[sizeof_array(catch_signals)];

void
setup_subproc_signals(const char *name)
{
	size_t i;
	struct sigaction catchsig;

	onerr_abort++;
	memset(&catchsig, 0, sizeof(catchsig));
	catchsig.sa_handler = SIG_IGN;
	sigemptyset(&catchsig.sa_mask);
	catchsig.sa_flags = 0;
	for (i = 0; i < sizeof_array(catch_signals); i++)
	if (sigaction(catch_signals[i], &catchsig, &uncatch_signals[i]))
		ohshite(_("unable to ignore signal %s before running %.250s"),
		        strsignal(catch_signals[i]), name);
	push_cleanup(cu_subproc_signals, ~0, NULL, 0, 0);
	onerr_abort--;
}

void
cu_subproc_signals(int argc, void **argv)
{
	size_t i;

	for (i = 0; i < sizeof_array(catch_signals); i++) {
		if (sigaction(catch_signals[i], &uncatch_signals[i], NULL)) {
			fprintf(stderr, _("error un-catching signal %s: %s\n"),
			        strsignal(catch_signals[i]), strerror(errno));
			onerr_abort++;
		}
	}
}

int
checksubprocerr(int status, const char *description, int flags)
{
	int n;

	if (WIFEXITED(status)) {
		n = WEXITSTATUS(status);
		if (!n)
			return 0;
		if (flags & PROCNOERR)
			return -1;
		if (flags & PROCWARN)
			warning(_("%s returned error exit status %d"),
			        description, n);
		else
			ohshit(_("subprocess %s returned error exit status %d"),
			       description, n);
	} else if (WIFSIGNALED(status)) {
		n = WTERMSIG(status);
		if (!n)
			return 0;
		if ((flags & PROCPIPE) && n == SIGPIPE)
			return 0;
		if (flags & PROCWARN)
			warning(_("%s killed by signal (%s)%s"),
			        description, strsignal(n),
			        WCOREDUMP(status) ? _(", core dumped") : "");
		else
			ohshit(_("subprocess %s killed by signal (%s)%s"),
			       description, strsignal(n),
			       WCOREDUMP(status) ? _(", core dumped") : "");
	} else {
		ohshit(_("subprocess %s failed with wait status code %d"),
		       description, status);
	}

	return -1;
}

int
waitsubproc(pid_t pid, const char *description, int flags)
{
	pid_t r;
	int status;

	while ((r = waitpid(pid, &status, 0)) == -1 && errno == EINTR) ;

	if (r != pid) {
		onerr_abort++;
		ohshite(_("wait for %s failed"), description);
	}

	return checksubprocerr(status, description, flags);
}