1 /* Test of flock() function.
2 Copyright (C) 2008-2010 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "signature.h"
22 SIGNATURE_CHECK (flock, int, (int, int));
31 test_shared (const char *file, int fd)
33 /* Should be able to acquire several shared locks on a file, through
34 * different file table entries.
38 ASSERT (flock (fd, LOCK_SH) == 0);
40 fd2 = open (file, O_RDWR, 0644);
43 r = flock (fd2, LOCK_SH | LOCK_NB);
44 ASSERT (r == 0); /* Was able to acquire a second shared lock. */
46 ASSERT (flock (fd, LOCK_UN) == 0);
47 ASSERT (close (fd2) == 0);
51 test_exclusive (const char *file, int fd)
53 /* Should not be able to acquire more than one exclusive lock on a file. */
56 ASSERT (flock (fd, LOCK_EX) == 0);
58 fd2 = open (file, O_RDWR, 0644);
61 r = flock (fd2, LOCK_SH | LOCK_NB);
62 ASSERT (r == -1); /* Was unable to acquire a second exclusive lock. */
64 ASSERT (flock (fd, LOCK_UN) == 0);
65 ASSERT (close (fd2) == 0);
69 main (int argc, char *argv[])
72 const char *file = "test-flock.txt";
74 /* Open a non-empty file for testing. */
75 fd = open (file, O_RDWR | O_CREAT | O_TRUNC, 0644);
77 ASSERT (write (fd, "hello", 5) == 5);
79 /* Some impossible operation codes which should never be accepted. */
80 ASSERT (flock (fd, LOCK_SH | LOCK_EX) == -1);
81 ASSERT (errno == EINVAL);
82 ASSERT (flock (fd, LOCK_SH | LOCK_UN) == -1);
83 ASSERT (errno == EINVAL);
84 ASSERT (flock (fd, LOCK_EX | LOCK_UN) == -1);
85 ASSERT (errno == EINVAL);
86 ASSERT (flock (fd, 0) == -1);
87 ASSERT (errno == EINVAL);
89 test_shared (file, fd);
90 test_exclusive (file, fd);
92 /* Close and remove the test file. */
93 ASSERT (close (fd) == 0);
94 ASSERT (unlink (file) == 0);