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 #include <support/xunistd.h>
  10
  11 static void prepare (void);
  12 #define PREPARE(argc, argv) prepare ()
  13
  14 static int do_test (void);
  15 #define TEST_FUNCTION do_test ()
  16
  17 #include "../test-skeleton.c"
  18
  19 static int dir_fd;
  20
  21 static void
  22 prepare (void)
  23 {
  24   size_t test_dir_len = strlen (test_dir);
  25   static const char dir_name[] = "/tst-openat.XXXXXX";
  26
  27   size_t dirbuflen = test_dir_len + sizeof (dir_name);
  28   char *dirbuf = malloc (dirbuflen);
  29   if (dirbuf == NULL)
  30     {
  31       puts ("out of memory");
  32       exit (1);
  33     }
  34
  35   snprintf (dirbuf, dirbuflen, "%s%s", test_dir, dir_name);
  36   if (mkdtemp (dirbuf) == NULL)
  37     {
  38       puts ("cannot create temporary directory");
  39       exit (1);
  40     }
  41
  42   add_temp_file (dirbuf);
  43
  44   dir_fd = open (dirbuf, O_RDONLY | O_DIRECTORY);
  45   if (dir_fd == -1)
  46     {
  47       puts ("cannot open directory");
  48       exit (1);
  49     }
  50 }
  51
  52
  53 static int
  54 do_test (void)
  55 {
  56   /* fdopendir takes over the descriptor, make a copy.  */
  57   int dupfd = dup (dir_fd);
  58   if (dupfd == -1)
  59     {
  60       puts ("dup failed");
  61       return 1;
  62     }
  63   if (lseek (dupfd, 0, SEEK_SET) != 0)
  64     {
  65       puts ("1st lseek failed");
  66       return 1;
  67     }
  68
  69   /* The directory should be empty safe the . and .. files.  */
  70   DIR *dir = fdopendir (dupfd);
  71   if (dir == NULL)
  72     {
  73       puts ("fdopendir failed");
  74       return 1;
  75     }
  76   struct dirent64 *d;
  77   while ((d = readdir64 (dir)) != NULL)
  78     if (strcmp (d->d_name, ".") != 0 && strcmp (d->d_name, "..") != 0)
  79       {
  80         printf ("temp directory contains file \"%s\"\n", d->d_name);
  81         return 1;
  82       }
  83   closedir (dir);
  84
  85   /* Try to create a file.  */
  86   int fd = openat (dir_fd, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666);
  87   if (fd == -1)
  88     {
  89       if (errno == ENOSYS)
  90         {
  91           puts ("*at functions not supported");
  92           return 0;
  93         }
  94
  95       puts ("file creation failed");
  96       return 1;
  97     }
  98   xwrite (fd, "hello", 5);
  99
 100   /* Before closing the file, try using this file descriptor to open
 101      another file.  This must fail.  */
 102   int fd2 = openat (fd, "should-not-work", O_CREAT|O_RDWR, 0666);
 103   if (fd2 != -1)
 104     {
 105       puts ("openat using descriptor for normal file worked");
 106       return 1;
 107     }
 108   if (errno != ENOTDIR)
 109     {
 110       puts ("error for openat using descriptor for normal file not ENOTDIR ");
 111       return 1;
 112     }
 113
 114   close (fd);
 115   puts ("file created");
 116
 117   /* fdopendir takes over the descriptor, make a copy.  */
 118   dupfd = dup (dir_fd);
 119   if (dupfd == -1)
 120     {
 121       puts ("dup failed");
 122       return 1;
 123     }
 124   if (lseek (dupfd, 0, SEEK_SET) != 0)
 125     {
 126       puts ("2nd lseek failed");
 127       return 1;
 128     }
 129
 130   /* The directory should be empty safe the . and .. files.  */
 131   dir = fdopendir (dupfd);
 132   if (dir == NULL)
 133     {
 134       puts ("fdopendir failed");
 135       return 1;
 136     }
 137   bool seen_file = false;
 138   while ((d = readdir64 (dir)) != NULL)
 139     if (strcmp (d->d_name, ".") != 0 && strcmp (d->d_name, "..") != 0)
 140       {
 141         if (strcmp (d->d_name, "some-file") != 0)
 142           {
 143             printf ("temp directory contains file \"%s\"\n", d->d_name);
 144             return 1;
 145           }
 146
 147         seen_file = true;
 148       }
 149   closedir (dir);
 150
 151   if (!seen_file)
 152     {
 153       puts ("file not created in correct directory");
 154       return 1;
 155     }
 156
 157   int cwdfd = open (".", O_RDONLY | O_DIRECTORY);
 158   if (cwdfd == -1)
 159     {
 160       puts ("cannot get descriptor for cwd");
 161       return 1;
 162     }
 163
 164   if (fchdir (dir_fd) != 0)
 165     {
 166       puts ("1st fchdir failed");
 167       return 1;
 168     }
 169
 170   if (unlink ("some-file") != 0)
 171     {
 172       puts ("unlink failed");
 173       return 1;
 174     }
 175
 176   if (fchdir (cwdfd) != 0)
 177     {
 178       puts ("2nd fchdir failed");
 179       return 1;
 180     }
 181
 182   close (dir_fd);
 183   close (cwdfd);
 184
 185   /* With the file descriptor closed the next call must fail.  */
 186   fd = openat (dir_fd, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666);
 187   if (fd != -1)
 188     {
 189       puts ("openat using closed descriptor succeeded");
 190       return 1;
 191     }
 192   if (errno != EBADF)
 193     {
 194       puts ("openat using closed descriptor did not set EBADF");
 195       return 1;
 196     }
 197
 198   fd = openat (-1, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666);
 199   if (fd != -1)
 200     {
 201       puts ("openat using -1 descriptor succeeded");
 202       return 1;
 203     }
 204   if (errno != EBADF)
 205     {
 206       puts ("openat using -1 descriptor did not set EBADF");
 207       return 1;
 208     }
 209
 210   return 0;
 211 }