io/tst-openat.c

   1 #include <dirent.h>
   2 #include <fcntl.h>
   3 #include <stdbool.h>
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <unistd.h>
   8
   9
  10 static void prepare (void);
  11 #define PREPARE(argc, argv) prepare ()
  12
  13 static int do_test (void);
  14 #define TEST_FUNCTION do_test ()
  15
  16 #include "../test-skeleton.c"
  17
  18 static int dir_fd;
  19
  20 static void
  21 prepare (void)
  22 {
  23   size_t test_dir_len = strlen (test_dir);
  24   static const char dir_name[] = "/tst-openat.XXXXXX";
  25
  26   size_t dirbuflen = test_dir_len + sizeof (dir_name);
  27   char *dirbuf = malloc (dirbuflen);
  28   if (dirbuf == NULL)
  29     {
  30       puts ("out of memory");
  31       exit (1);
  32     }
  33
  34   snprintf (dirbuf, dirbuflen, "%s%s", test_dir, dir_name);
  35   if (mkdtemp (dirbuf) == NULL)
  36     {
  37       puts ("cannot create temporary directory");
  38       exit (1);
  39     }
  40
  41   add_temp_file (dirbuf);
  42
  43   dir_fd = open (dirbuf, O_RDONLY | O_DIRECTORY);
  44   if (dir_fd == -1)
  45     {
  46       puts ("cannot open directory");
  47       exit (1);
  48     }
  49 }
  50
  51
  52 static int
  53 do_test (void)
  54 {
  55   /* fdopendir takes over the descriptor, make a copy.  */
  56   int dupfd = dup (dir_fd);
  57   if (dupfd == -1)
  58     {
  59       puts ("dup failed");
  60       return 1;
  61     }
  62   if (lseek (dupfd, 0, SEEK_SET) != 0)
  63     {
  64       puts ("1st lseek failed");
  65       return 1;
  66     }
  67
  68   /* The directory should be empty safe the . and .. files.  */
  69   DIR *dir = fdopendir (dupfd);
  70   if (dir == NULL)
  71     {
  72       puts ("fdopendir failed");
  73       return 1;
  74     }
  75   struct dirent64 *d;
  76   while ((d = readdir64 (dir)) != NULL)
  77     if (strcmp (d->d_name, ".") != 0 && strcmp (d->d_name, "..") != 0)
  78       {
  79         printf ("temp directory contains file \"%s\"\n", d->d_name);
  80         return 1;
  81       }
  82   closedir (dir);
  83
  84   /* Try to create a file.  */
  85   int fd = openat (dir_fd, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666);
  86   if (fd == -1)
  87     {
  88       if (errno == ENOSYS)
  89         {
  90           puts ("*at functions not supported");
  91           return 0;
  92         }
  93
  94       puts ("file creation failed");
  95       return 1;
  96     }
  97   write (fd, "hello", 5);
  98
  99   /* Before closing the file, try using this file descriptor to open
 100      another file.  This must fail.  */
 101   int fd2 = openat (fd, "should-not-work", O_CREAT|O_RDWR, 0666);
 102   if (fd2 != -1)
 103     {
 104       puts ("openat using descriptor for normal file worked");
 105       return 1;
 106     }
 107   if (errno != ENOTDIR)
 108     {
 109       puts ("error for openat using descriptor for normal file not ENOTDIR ");
 110       return 1;
 111     }
 112
 113   close (fd);
 114   puts ("file created");
 115
 116   /* fdopendir takes over the descriptor, make a copy.  */
 117   dupfd = dup (dir_fd);
 118   if (dupfd == -1)
 119     {
 120       puts ("dup failed");
 121       return 1;
 122     }
 123   if (lseek (dupfd, 0, SEEK_SET) != 0)
 124     {
 125       puts ("2nd lseek failed");
 126       return 1;
 127     }
 128
 129   /* The directory should be empty safe the . and .. files.  */
 130   dir = fdopendir (dupfd);
 131   if (dir == NULL)
 132     {
 133       puts ("fdopendir failed");
 134       return 1;
 135     }
 136   bool seen_file = false;
 137   while ((d = readdir64 (dir)) != NULL)
 138     if (strcmp (d->d_name, ".") != 0 && strcmp (d->d_name, "..") != 0)
 139       {
 140         if (strcmp (d->d_name, "some-file") != 0)
 141           {
 142             printf ("temp directory contains file \"%s\"\n", d->d_name);
 143             return 1;
 144           }
 145
 146         seen_file = true;
 147       }
 148   closedir (dir);
 149
 150   if (!seen_file)
 151     {
 152       puts ("file not created in correct directory");
 153       return 1;
 154     }
 155
 156   int cwdfd = open (".", O_RDONLY | O_DIRECTORY);
 157   if (cwdfd == -1)
 158     {
 159       puts ("cannot get descriptor for cwd");
 160       return 1;
 161     }
 162
 163   if (fchdir (dir_fd) != 0)
 164     {
 165       puts ("1st fchdir failed");
 166       return 1;
 167     }
 168
 169   if (unlink ("some-file") != 0)
 170     {
 171       puts ("unlink failed");
 172       return 1;
 173     }
 174
 175   if (fchdir (cwdfd) != 0)
 176     {
 177       puts ("2nd fchdir failed");
 178       return 1;
 179     }
 180
 181   close (dir_fd);
 182   close (cwdfd);
 183
 184   /* With the file descriptor closed the next call must fail.  */
 185   fd = openat (dir_fd, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666);
 186   if (fd != -1)
 187     {
 188       puts ("openat using closed descriptor succeeded");
 189       return 1;
 190     }
 191   if (errno != EBADF)
 192     {
 193       puts ("openat using closed descriptor did not set EBADF");
 194       return 1;
 195     }
 196
 197   fd = openat (-1, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666);
 198   if (fd != -1)
 199     {
 200       puts ("openat using -1 descriptor succeeded");
 201       return 1;
 202     }
 203   if (errno != EBADF)
 204     {
 205       puts ("openat using -1 descriptor did not set EBADF");
 206       return 1;
 207     }
 208
 209   return 0;
 210 }