Imported from util-linux-2.12j tarball.

1 files changed, 116 insertions, 0 deletions

diff --git a/sys-utils/flock.c b/sys-utils/flock.c
new file mode 100644
index 000000000..524d28a64
--- /dev/null
+++ b/sys-utils/flock.c
@@ -0,0 +1,116 @@
+/*
+    flock - acquires a file lock and executes a command with the lock held.
+    Usage: flock [--shared | --timeout=seconds] lockfile program [args...]
+
+    Written by Adam J. Richter
+    Copyright (C) 2004 Yggdrasil Computing, Inc.
+
+    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, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+#include <sys/file.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <getopt.h>
+#include <unistd.h>
+#include <stdlib.h>		/* exit */
+#include <signal.h>		/* kill */
+#include <stdio.h>
+#include "nls.h"
+
+static int non_blocking = 0;
+static int shared = LOCK_EX;
+
+static const struct option options[] = {
+	{"shared",	no_argument,		&shared,	LOCK_SH },
+	{"timeout",	required_argument,	NULL,		't' },
+	{NULL,		0,			NULL,		0  },
+};
+
+int main(int argc, char **argv)
+{
+	int fd;
+	int opt;
+	int pid;
+	int child_status;
+	int option_index;
+	int timeout = 0;
+
+	setlocale(LC_ALL, "");
+	bindtextdomain(PACKAGE, LOCALEDIR);
+	textdomain(PACKAGE);
+
+	do {
+		opt = getopt_long(argc, argv, "+", options, &option_index);
+		switch(opt) {
+		case '?':
+			fprintf (stderr,
+				 _("flock: unknown option, aborting.\n"));
+			exit(1);
+			break;
+		case 't':
+			timeout = atoi(optarg);
+			if (timeout == 0)
+				non_blocking |= LOCK_NB;
+			break;
+		default:
+			break;
+		}
+	} while (opt != -1);
+
+	argc -= optind;
+	argv += optind;
+
+	if (argc < 2) {
+		fprintf(stderr,
+			_("Usage flock [--shared | --timeout=seconds] "
+			  "filename command {arg arg...}\n"));
+		exit(2);
+	}
+
+	fd = open(argv[0], O_RDONLY);
+	if (fd < 0) {
+		perror(argv[0]);
+		exit(3);
+	}
+
+	alarm(timeout);
+	if (flock(fd, shared | non_blocking) != 0) {
+		perror("flock");
+		exit(4);
+	}
+	alarm(0);
+
+	pid = fork();
+	if (pid < 0) {
+		perror("fork");
+		exit(5);
+	}
+	if (pid == 0) {
+		execvp(argv[1], argv+1);
+		perror(argv[1]);
+		exit(6);
+	}
+	waitpid(pid, &child_status, 0);
+
+	/* flock(fd, LOCK_UN); */
+	/* No need to explicitly release the flock, since we are just
+	   going to exit now anyhow. */
+
+	/* Lame attempt to simulate child's mode of death. */
+	if (WIFSIGNALED(child_status))
+		kill(0, WTERMSIG(child_status));
+
+	return WEXITSTATUS(child_status);
+}