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/* test whether 64 bit fcntl locking really works on this system */
#if defined(HAVE_UNISTD_H)
#include <unistd.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_SYS_FCNTL_H
#include <sys/fcntl.h>
#endif
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#include <errno.h>
static int sys_waitpid(pid_t pid,int *status,int options)
{
#ifdef HAVE_WAITPID
return waitpid(pid,status,options);
#else /* USE_WAITPID */
return wait4(pid, status, options, NULL);
#endif /* USE_WAITPID */
}
#define DATA "conftest.fcntl64"
/* lock a byte range in a open file */
int main(int argc, char *argv[])
{
struct flock64 lock;
int fd, ret, status=1;
pid_t pid;
if (!(pid=fork())) {
sleep(2);
fd = open64(DATA, O_RDONLY);
if (fd == -1) return 1;
lock.l_type = F_WRLCK;
lock.l_whence = SEEK_SET;
lock.l_start = 0;
lock.l_len = 4;
lock.l_pid = getpid();
lock.l_type = F_WRLCK;
/* check if a lock applies */
ret = fcntl(fd,F_GETLK64,&lock);
if ((ret == -1) ||
(lock.l_type == F_UNLCK)) {
/* printf("No lock conflict\n"); */
return 1;
} else {
/* printf("lock conflict\n"); */
return 0;
}
}
fd = open64(DATA, O_RDWR|O_CREAT|O_TRUNC, 0600);
lock.l_type = F_WRLCK;
lock.l_whence = SEEK_SET;
#if defined(COMPILER_SUPPORTS_LL)
lock.l_start = 0x100000000LL;
#else
lock.l_start = 0x100000000;
#endif
lock.l_len = 4;
lock.l_pid = getpid();
/* set a 4 byte write lock */
fcntl(fd,F_SETLK64,&lock);
sys_waitpid(pid, &status, 0);
#if defined(WIFEXITED) && defined(WEXITSTATUS)
if(WIFEXITED(status)) {
status = WEXITSTATUS(status);
} else {
status = 1;
}
#else /* defined(WIFEXITED) && defined(WEXITSTATUS) */
status = (status == 0) ? 0 : 1;
#endif /* defined(WIFEXITED) && defined(WEXITSTATUS) */
unlink(DATA);
return status;
}
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