/* Test of flock() function.
- Copyright (C) 2008 Free Software Foundation, Inc.
+ Copyright (C) 2008-2011 Free Software Foundation, 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
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
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 <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <errno.h>
+#include <config.h>
#include <sys/file.h>
-#define ASSERT(expr) \
- do \
- { \
- if (!(expr)) \
- { \
- fprintf (stderr, "%s:%d: assertion failed, errno = %d\n", \
- __FILE__, __LINE__, errno); \
- fflush (stderr); \
- abort (); \
- } \
- } \
- while (0)
+#include "signature.h"
+SIGNATURE_CHECK (flock, int, (int, int));
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "macros.h"
static void
test_shared (const char *file, int fd)
ASSERT (fd2 >= 0);
r = flock (fd2, LOCK_SH | LOCK_NB);
- ASSERT (r == 0); /* Was able to acquire a second shared lock. */
+ ASSERT (r == 0); /* Was able to acquire a second shared lock. */
ASSERT (flock (fd, LOCK_UN) == 0);
ASSERT (close (fd2) == 0);
fd2 = open (file, O_RDWR, 0644);
ASSERT (fd2 >= 0);
+ r = flock (fd2, LOCK_EX | LOCK_NB);
+ ASSERT (r == -1); /* Was unable to acquire a second exclusive lock. */
+
+#if 0
+ /* The Linux manual page of flock(2) says:
+ "A process may only hold one type of lock (shared or exclusive) on a
+ file. Subsequent flock() calls on an already locked file will convert
+ an existing lock to the new lock mode."
+ So, the call below should convert the exclusive lock for fd to a shared
+ and thus succeeds. The fact that it doesn't but instead fails is
+ apparently a bug. */
+ /* The Solaris manual page of flock(2) says:
+ "More than one process may hold a shared lock for a file at any given
+ time, but multiple exclusive, or both shared and exclusive, locks may
+ not exist simultaneously on a file. ...
+ Requesting a lock on an object that is already locked normally causes
+ the caller to block until the lock may be acquired. If LOCK_NB is
+ included in operation, then this will not happen; instead, the call
+ will fail and the error EWOULDBLOCK will be returned."
+ So, the call below should fail and set errno to EWOULDBLOCK. The fact
+ that it succeeds is apparently a bug. */
r = flock (fd2, LOCK_SH | LOCK_NB);
- ASSERT (r == -1); /* Was unable to acquire a second exclusive lock. */
+ ASSERT (r == -1);
+#endif
ASSERT (flock (fd, LOCK_UN) == 0);
ASSERT (close (fd2) == 0);
ASSERT (fd >= 0);
ASSERT (write (fd, "hello", 5) == 5);
- /* Some impossible operation codes which should never be accepted. */
+#if defined __linux__
+ /* Invalid operation codes are rejected by the Linux implementation and by
+ the gnulib replacement, but not by the MacOS X implementation. */
ASSERT (flock (fd, LOCK_SH | LOCK_EX) == -1);
ASSERT (errno == EINVAL);
ASSERT (flock (fd, LOCK_SH | LOCK_UN) == -1);
ASSERT (errno == EINVAL);
ASSERT (flock (fd, 0) == -1);
ASSERT (errno == EINVAL);
+#endif
test_shared (file, fd);
test_exclusive (file, fd);