libio/bug-fclose1.c

   1 // BZ #12724
   2
   3 static void do_prepare (void);
   4 #define PREPARE(argc, argv) do_prepare ()
   5 static int do_test (void);
   6 #define TEST_FUNCTION do_test()
   7 #include "../test-skeleton.c"
   8
   9
  10 static int fd;
  11
  12
  13 static void
  14 do_prepare (void)
  15 {
  16   fd = create_temp_file ("bug-fclose1.", NULL);
  17   if (fd == -1)
  18     {
  19       printf ("cannot create temporary file: %m\n");
  20       exit (1);
  21     }
  22 }
  23
  24
  25 static int
  26 do_test (void)
  27 {
  28   static const char pattern[] = "hello world";
  29
  30   /* Prepare a seekable file.  */
  31   if (write (fd, pattern, sizeof pattern) != sizeof pattern)
  32     {
  33       printf ("cannot write pattern: %m\n");
  34       return 1;
  35     }
  36   if (lseek (fd, 1, SEEK_SET) != 1)
  37     {
  38       printf ("cannot seek after write: %m\n");
  39       return 1;
  40     }
  41
  42   /* Create an output stream visiting the file; when it is closed, all
  43      other file descriptors visiting the file must see the new file
  44      position.  */
  45   int fd2 = dup (fd);
  46   if (fd2 < 0)
  47     {
  48       printf ("cannot duplicate descriptor for writing: %m\n");
  49       return 1;
  50     }
  51   FILE *f = fdopen (fd2, "w");
  52   if (f == NULL)
  53     {
  54       printf ("first fdopen failed: %m\n");
  55       return 1;
  56     }
  57   if (fputc (pattern[1], f) != pattern[1])
  58     {
  59       printf ("fputc failed: %m\n");
  60       return 1;
  61     }
  62   if (fclose (f) != 0)
  63     {
  64       printf ("first fclose failed: %m\n");
  65       return 1;
  66     }
  67   errno = 0;
  68   if (lseek (fd2, 0, SEEK_CUR) != -1)
  69     {
  70       printf ("lseek after fclose after write did not fail\n");
  71       return 1;
  72     }
  73   if (errno != EBADF)
  74     {
  75       printf ("lseek after fclose after write did not fail with EBADF: %m\n");
  76       return 1;
  77     }
  78   off_t o = lseek (fd, 0, SEEK_CUR);
  79   if (o != 2)
  80     {
  81       printf ("\
  82 lseek on original descriptor after first fclose returned %ld, expected 2\n",
  83               (long int) o);
  84       return 1;
  85     }
  86
  87   /* Likewise for an input stream.  */
  88   fd2 = dup (fd);
  89   if (fd2 < 0)
  90      {
  91       printf ("cannot duplicate descriptor for reading: %m\n");
  92       return 1;
  93     }
  94   f = fdopen (fd2, "r");
  95    if (f == NULL)
  96     {
  97       printf ("second fdopen failed: %m\n");
  98       return 1;
  99     }
 100    char c = fgetc (f);
 101    if (c != pattern[2])
 102      {
 103        printf ("getc returned %c, expected %c\n", c, pattern[2]);
 104        return 1;
 105      }
 106   if (fclose (f) != 0)
 107     {
 108       printf ("second fclose failed: %m\n");
 109       return 1;
 110     }
 111   errno = 0;
 112   if (lseek (fd2, 0, SEEK_CUR) != -1)
 113     {
 114       printf ("lseek after fclose after read did not fail\n");
 115       return 1;
 116     }
 117   if (errno != EBADF)
 118     {
 119       printf ("lseek after fclose after read did not fail with EBADF: %m\n");
 120       return 1;
 121     }
 122   o = lseek (fd, 0, SEEK_CUR);
 123   if (o != 3)
 124     {
 125       printf ("\
 126 lseek on original descriptor after second fclose returned %ld, expected 3\n",
 127               (long int) o);
 128       return 1;
 129     }
 130
 131   return 0;
 132 }