Adding upstream version 2.33.1.upstream/2.33.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 380 insertions, 0 deletions

diff --git a/sys-utils/flock.c b/sys-utils/flock.c
new file mode 100644
index 0000000..ed25230
--- /dev/null
+++ b/sys-utils/flock.c
@@ -0,0 +1,380 @@
+/*   Copyright 2003-2005 H. Peter Anvin - All Rights Reserved
+ *
+ *   Permission is hereby granted, free of charge, to any person
+ *   obtaining a copy of this software and associated documentation
+ *   files (the "Software"), to deal in the Software without
+ *   restriction, including without limitation the rights to use,
+ *   copy, modify, merge, publish, distribute, sublicense, and/or
+ *   sell copies of the Software, and to permit persons to whom
+ *   the Software is furnished to do so, subject to the following
+ *   conditions:
+ *
+ *   The above copyright notice and this permission notice shall
+ *   be included in all copies or substantial portions of the Software.
+ *
+ *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *   OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <paths.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "c.h"
+#include "nls.h"
+#include "strutils.h"
+#include "closestream.h"
+#include "monotonic.h"
+#include "timer.h"
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+	fputs(USAGE_HEADER, stdout);
+	printf(
+		_(" %1$s [options] <file>|<directory> <command> [<argument>...]\n"
+		  " %1$s [options] <file>|<directory> -c <command>\n"
+		  " %1$s [options] <file descriptor number>\n"),
+		program_invocation_short_name);
+
+	fputs(USAGE_SEPARATOR, stdout);
+	fputs(_("Manage file locks from shell scripts.\n"), stdout);
+
+	fputs(USAGE_OPTIONS, stdout);
+	fputs(_(  " -s, --shared             get a shared lock\n"), stdout);
+	fputs(_(  " -x, --exclusive          get an exclusive lock (default)\n"), stdout);
+	fputs(_(  " -u, --unlock             remove a lock\n"), stdout);
+	fputs(_(  " -n, --nonblock           fail rather than wait\n"), stdout);
+	fputs(_(  " -w, --timeout <secs>     wait for a limited amount of time\n"), stdout);
+	fputs(_(  " -E, --conflict-exit-code <number>  exit code after conflict or timeout\n"), stdout);
+	fputs(_(  " -o, --close              close file descriptor before running command\n"), stdout);
+	fputs(_(  " -c, --command <command>  run a single command string through the shell\n"), stdout);
+	fputs(_(  " -F, --no-fork            execute command without forking\n"), stdout);
+	fputs(_(  "     --verbose            increase verbosity\n"), stdout);
+	fputs(USAGE_SEPARATOR, stdout);
+	printf(USAGE_HELP_OPTIONS(26));
+	printf(USAGE_MAN_TAIL("flock(1)"));
+	exit(EXIT_SUCCESS);
+}
+
+static sig_atomic_t timeout_expired = 0;
+
+static void timeout_handler(int sig __attribute__((__unused__)),
+			    siginfo_t *info,
+			    void *context __attribute__((__unused__)))
+{
+	if (info->si_code == SI_TIMER)
+		timeout_expired = 1;
+}
+
+static int open_file(const char *filename, int *flags)
+{
+
+	int fd;
+	int fl = *flags == 0 ? O_RDONLY : *flags;
+
+	errno = 0;
+	fl |= O_NOCTTY | O_CREAT;
+	fd = open(filename, fl, 0666);
+
+	/* Linux doesn't like O_CREAT on a directory, even though it
+	 * should be a no-op; POSIX doesn't allow O_RDWR or O_WRONLY
+	 */
+	if (fd < 0 && errno == EISDIR) {
+		fl = O_RDONLY | O_NOCTTY;
+		fd = open(filename, fl);
+	}
+	if (fd < 0) {
+		warn(_("cannot open lock file %s"), filename);
+		if (errno == ENOMEM || errno == EMFILE || errno == ENFILE)
+			exit(EX_OSERR);
+		if (errno == EROFS || errno == ENOSPC)
+			exit(EX_CANTCREAT);
+		exit(EX_NOINPUT);
+	}
+	*flags = fl;
+	return fd;
+}
+
+static void __attribute__((__noreturn__)) run_program(char **cmd_argv)
+{
+	execvp(cmd_argv[0], cmd_argv);
+
+	warn(_("failed to execute %s"), cmd_argv[0]);
+	_exit((errno == ENOMEM) ? EX_OSERR : EX_UNAVAILABLE);
+}
+
+int main(int argc, char *argv[])
+{
+	static timer_t t_id;
+	struct itimerval timeout;
+	int have_timeout = 0;
+	int type = LOCK_EX;
+	int block = 0;
+	int open_flags = 0;
+	int fd = -1;
+	int opt, ix;
+	int do_close = 0;
+	int no_fork = 0;
+	int status;
+	int verbose = 0;
+	struct timeval time_start, time_done;
+	/*
+	 * The default exit code for lock conflict or timeout
+	 * is specified in man flock.1
+	 */
+	int conflict_exit_code = 1;
+	char **cmd_argv = NULL, *sh_c_argv[4];
+	const char *filename = NULL;
+	enum {
+		OPT_VERBOSE = CHAR_MAX + 1
+	};
+	static const struct option long_options[] = {
+		{"shared", no_argument, NULL, 's'},
+		{"exclusive", no_argument, NULL, 'x'},
+		{"unlock", no_argument, NULL, 'u'},
+		{"nonblocking", no_argument, NULL, 'n'},
+		{"nb", no_argument, NULL, 'n'},
+		{"timeout", required_argument, NULL, 'w'},
+		{"wait", required_argument, NULL, 'w'},
+		{"conflict-exit-code", required_argument, NULL, 'E'},
+		{"close", no_argument, NULL, 'o'},
+		{"no-fork", no_argument, NULL, 'F'},
+		{"verbose", no_argument, NULL, OPT_VERBOSE},
+		{"help", no_argument, NULL, 'h'},
+		{"version", no_argument, NULL, 'V'},
+		{NULL, 0, NULL, 0}
+	};
+
+	setlocale(LC_ALL, "");
+	bindtextdomain(PACKAGE, LOCALEDIR);
+	textdomain(PACKAGE);
+	atexit(close_stdout);
+
+	strutils_set_exitcode(EX_USAGE);
+
+	if (argc < 2) {
+		warnx(_("not enough arguments"));
+		errtryhelp(EX_USAGE);
+	}
+
+	memset(&timeout, 0, sizeof timeout);
+
+	optopt = 0;
+	while ((opt =
+		getopt_long(argc, argv, "+sexnoFuw:E:hV?", long_options,
+			    &ix)) != EOF) {
+		switch (opt) {
+		case 's':
+			type = LOCK_SH;
+			break;
+		case 'e':
+		case 'x':
+			type = LOCK_EX;
+			break;
+		case 'u':
+			type = LOCK_UN;
+			break;
+		case 'o':
+			do_close = 1;
+			break;
+		case 'F':
+			no_fork = 1;
+			break;
+		case 'n':
+			block = LOCK_NB;
+			break;
+		case 'w':
+			have_timeout = 1;
+			strtotimeval_or_err(optarg, &timeout.it_value,
+				_("invalid timeout value"));
+			break;
+		case 'E':
+			conflict_exit_code = strtos32_or_err(optarg,
+				_("invalid exit code"));
+			break;
+		case OPT_VERBOSE:
+			verbose = 1;
+			break;
+		case 'V':
+			printf(UTIL_LINUX_VERSION);
+			exit(EX_OK);
+		case 'h':
+			usage();
+		default:
+			errtryhelp(EX_USAGE);
+		}
+	}
+
+	if (no_fork && do_close)
+		errx(EX_USAGE,
+			_("the --no-fork and --close options are incompatible"));
+
+	if (argc > optind + 1) {
+		/* Run command */
+		if (!strcmp(argv[optind + 1], "-c") ||
+		    !strcmp(argv[optind + 1], "--command")) {
+			if (argc != optind + 3)
+				errx(EX_USAGE,
+				     _("%s requires exactly one command argument"),
+				     argv[optind + 1]);
+			cmd_argv = sh_c_argv;
+			cmd_argv[0] = getenv("SHELL");
+			if (!cmd_argv[0] || !*cmd_argv[0])
+				cmd_argv[0] = _PATH_BSHELL;
+			cmd_argv[1] = "-c";
+			cmd_argv[2] = argv[optind + 2];
+			cmd_argv[3] = NULL;
+		} else {
+			cmd_argv = &argv[optind + 1];
+		}
+
+		filename = argv[optind];
+		fd = open_file(filename, &open_flags);
+
+	} else if (optind < argc) {
+		/* Use provided file descriptor */
+		fd = strtos32_or_err(argv[optind], _("bad file descriptor"));
+	} else {
+		/* Bad options */
+		errx(EX_USAGE, _("requires file descriptor, file or directory"));
+	}
+
+	if (have_timeout) {
+		if (timeout.it_value.tv_sec == 0 &&
+		    timeout.it_value.tv_usec == 0) {
+			/* -w 0 is equivalent to -n; this has to be
+			 * special-cased because setting an itimer to zero
+			 * means disabled!
+			 */
+			have_timeout = 0;
+			block = LOCK_NB;
+		} else
+			if (setup_timer(&t_id, &timeout, &timeout_handler))
+				err(EX_OSERR, _("cannot set up timer"));
+	}
+
+	if (verbose)
+		gettime_monotonic(&time_start);
+	while (flock(fd, type | block)) {
+		switch (errno) {
+		case EWOULDBLOCK:
+			/* -n option set and failed to lock. */
+			if (verbose)
+				warnx(_("failed to get lock"));
+			exit(conflict_exit_code);
+		case EINTR:
+			/* Signal received */
+			if (timeout_expired) {
+				/* -w option set and failed to lock. */
+				if (verbose)
+					warnx(_("timeout while waiting to get lock"));
+				exit(conflict_exit_code);
+			}
+			/* otherwise try again */
+			continue;
+		case EIO:
+		case EBADF:		/* since Linux 3.4 (commit 55725513) */
+			/* Probably NFSv4 where flock() is emulated by fcntl().
+			 * Let's try to reopen in read-write mode.
+			 */
+			if (!(open_flags & O_RDWR) &&
+			    type != LOCK_SH &&
+			    filename &&
+			    access(filename, R_OK | W_OK) == 0) {
+
+				close(fd);
+				open_flags = O_RDWR;
+				fd = open_file(filename, &open_flags);
+
+				if (open_flags & O_RDWR)
+					break;
+			}
+			/* fallthrough */
+		default:
+			/* Other errors */
+			if (filename)
+				warn("%s", filename);
+			else
+				warn("%d", fd);
+			exit((errno == ENOLCK
+			      || errno == ENOMEM) ? EX_OSERR : EX_DATAERR);
+		}
+	}
+
+	if (have_timeout)
+		cancel_timer(&t_id);
+	if (verbose) {
+		struct timeval delta;
+
+		gettime_monotonic(&time_done);
+		timersub(&time_done, &time_start, &delta);
+		printf(_("%s: getting lock took %ld.%06ld seconds\n"),
+		       program_invocation_short_name, delta.tv_sec,
+		       delta.tv_usec);
+	}
+	status = EX_OK;
+
+	if (cmd_argv) {
+		pid_t w, f;
+		/* Clear any inherited settings */
+		signal(SIGCHLD, SIG_DFL);
+		if (verbose)
+			printf(_("%s: executing %s\n"), program_invocation_short_name, cmd_argv[0]);
+
+		if (!no_fork) {
+			f = fork();
+			if (f < 0)
+				err(EX_OSERR, _("fork failed"));
+
+			/* child */
+			else if (f == 0) {
+				if (do_close)
+					close(fd);
+				run_program(cmd_argv);
+
+			/* parent */
+			} else {
+				do {
+					w = waitpid(f, &status, 0);
+					if (w == -1 && errno != EINTR)
+						break;
+				} while (w != f);
+
+				if (w == -1) {
+					status = EXIT_FAILURE;
+					warn(_("waitpid failed"));
+				} else if (WIFEXITED(status))
+					status = WEXITSTATUS(status);
+				else if (WIFSIGNALED(status))
+					status = WTERMSIG(status) + 128;
+				else
+					/* WTF? */
+					status = EX_OSERR;
+			}
+
+		} else
+			/* no-fork execution */
+			run_program(cmd_argv);
+	}
+
+	return status;
+}