io/tst-openat.c

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