1/* test whether fcntl locking works on this system */
2
3#if defined(HAVE_UNISTD_H)
4#include <unistd.h>
5#endif
6
7#include <stdio.h>
8#include <stdlib.h>
9#include <sys/types.h>
10
11#ifdef HAVE_FCNTL_H
12#include <fcntl.h>
13#endif
14
15#ifdef HAVE_SYS_FCNTL_H
16#include <sys/fcntl.h>
17#endif
18
19#ifdef HAVE_SYS_WAIT_H
20#include <sys/wait.h>
21#endif
22
23#include <errno.h>
24
25static int sys_waitpid(pid_t pid,int *status,int options)
26{
27#ifdef HAVE_WAITPID
28  return waitpid(pid,status,options);
29#else /* USE_WAITPID */
30  return wait4(pid, status, options, NULL);
31#endif /* USE_WAITPID */
32}
33
34#define DATA "conftest.fcntl"
35
36#ifndef SEEK_SET
37#define SEEK_SET 0
38#endif
39
40/* lock a byte range in a open file */
41int main(int argc, char *argv[])
42{
43	struct flock lock;
44	int fd, ret, status=1;
45	pid_t pid;
46	char *testdir = NULL;
47
48	testdir = getenv("TESTDIR");
49	if (testdir) chdir(testdir);
50
51	alarm(10);
52
53	if (!(pid=fork())) {
54		sleep(2);
55		fd = open(DATA, O_RDONLY);
56
57		if (fd == -1) {
58			fprintf(stderr,"ERROR: failed to open %s (errno=%d)\n",
59				DATA, (int)errno);
60			exit(1);
61		}
62
63		lock.l_type = F_WRLCK;
64		lock.l_whence = SEEK_SET;
65		lock.l_start = 0;
66		lock.l_len = 4;
67		lock.l_pid = getpid();
68
69		lock.l_type = F_WRLCK;
70
71		/* check if a lock applies */
72		ret = fcntl(fd,F_GETLK,&lock);
73
74		if ((ret == -1) ||
75		    (lock.l_type == F_UNLCK)) {
76			fprintf(stderr,"ERROR: lock test failed (ret=%d errno=%d)\n", ret, (int)errno);
77			exit(1);
78		} else {
79			exit(0);
80		}
81	}
82
83	unlink(DATA);
84	fd = open(DATA, O_RDWR|O_CREAT|O_EXCL, 0600);
85
86	if (fd == -1) {
87		fprintf(stderr,"ERROR: failed to open %s (errno=%d)\n",
88			DATA, (int)errno);
89		exit(1);
90	}
91
92	lock.l_type = F_WRLCK;
93	lock.l_whence = SEEK_SET;
94	lock.l_start = 0;
95	lock.l_len = 4;
96	lock.l_pid = getpid();
97
98	/* set a 4 byte write lock */
99	fcntl(fd,F_SETLK,&lock);
100
101	sys_waitpid(pid, &status, 0);
102
103	unlink(DATA);
104
105#if defined(WIFEXITED) && defined(WEXITSTATUS)
106    if(WIFEXITED(status)) {
107        status = WEXITSTATUS(status);
108    } else {
109        status = 1;
110    }
111#else /* defined(WIFEXITED) && defined(WEXITSTATUS) */
112	status = (status == 0) ? 0 : 1;
113#endif /* defined(WIFEXITED) && defined(WEXITSTATUS) */
114
115	if (status) {
116		fprintf(stderr,"ERROR: lock test failed with status=%d\n",
117			status);
118	}
119
120	exit(status);
121}
122