source/tests/fcntl_lock64.c

   1 /* test whether 64 bit fcntl locking really 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
  25 static 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.fcntl64"
  35
  36 /* lock a byte range in a open file */
  37 int main(int argc, char *argv[])
  38 {
  39         struct flock64 lock;
  40         int fd, ret, status=1;
  41         pid_t pid;
  42
  43         if (!(pid=fork())) {
  44                 sleep(2);
  45                 fd = open64(DATA, O_RDONLY);
  46
  47                 if (fd == -1) return 1;
  48
  49                 lock.l_type = F_WRLCK;
  50                 lock.l_whence = SEEK_SET;
  51                 lock.l_start = 0;
  52                 lock.l_len = 4;
  53                 lock.l_pid = getpid();
  54
  55                 lock.l_type = F_WRLCK;
  56
  57                 /* check if a lock applies */
  58                 ret = fcntl(fd,F_GETLK64,&lock);
  59
  60                 if ((ret == -1) ||
  61                     (lock.l_type == F_UNLCK)) {
  62 /*            printf("No lock conflict\n"); */
  63                         return 1;
  64                 } else {
  65 /*            printf("lock conflict\n"); */
  66                         return 0;
  67                 }
  68         }
  69
  70         fd = open64(DATA, O_RDWR|O_CREAT|O_TRUNC, 0600);
  71
  72         lock.l_type = F_WRLCK;
  73         lock.l_whence = SEEK_SET;
  74 #if defined(COMPILER_SUPPORTS_LL)
  75         lock.l_start = 0x100000000LL;
  76 #else
  77         lock.l_start = 0x100000000;
  78 #endif
  79         lock.l_len = 4;
  80         lock.l_pid = getpid();
  81
  82         /* set a 4 byte write lock */
  83         fcntl(fd,F_SETLK64,&lock);
  84
  85         sys_waitpid(pid, &status, 0);
  86
  87 #if defined(WIFEXITED) && defined(WEXITSTATUS)
  88         if(WIFEXITED(status)) {
  89                 status = WEXITSTATUS(status);
  90         } else {
  91                 status = 1;
  92         }
  93 #else /* defined(WIFEXITED) && defined(WEXITSTATUS) */
  94         status = (status == 0) ? 0 : 1;
  95 #endif /* defined(WIFEXITED) && defined(WEXITSTATUS) */
  96
  97         unlink(DATA);
  98
  99         return status;
 100 }