io/tst-symlinkat.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 #include <sys/stat.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-symlinkat.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   puts ("file created");
 100
 101   struct stat64 st1;
 102   if (fstat64 (fd, &st1) != 0)
 103     {
 104       puts ("fstat64 failed");
 105       return 1;
 106     }
 107
 108   close (fd);
 109
 110   if (symlinkat ("some-file", dir_fd, "another-file") != 0)
 111     {
 112       puts ("symlinkat failed");
 113       return 1;
 114     }
 115
 116   struct stat64 st2;
 117   if (fstatat64 (dir_fd, "some-file", &st2, 0) != 0)
 118     {
 119       puts ("fstatat64 failed");
 120       return 1;
 121     }
 122   if (st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino)
 123     {
 124       puts ("file changed after symlinkat");
 125       return 1;
 126     }
 127
 128   if (fstatat64 (dir_fd, "another-file", &st2, AT_SYMLINK_NOFOLLOW) != 0)
 129     {
 130       puts ("2nd fstatat64 failed");
 131       return 1;
 132     }
 133   if (!S_ISLNK (st2.st_mode))
 134     {
 135       puts ("2nd fstatat64 does not show file is a symlink");
 136       return 1;
 137     }
 138
 139   if (fstatat64 (dir_fd, "another-file", &st2, 0) != 0)
 140     {
 141       puts ("3rd fstatat64 failed");
 142       return 1;
 143     }
 144   if (st1.st_dev != st2.st_dev
 145       || st1.st_ino != st2.st_ino
 146       || st1.st_size != st2.st_size)
 147     {
 148       puts ("stat results do not match");
 149       return 1;
 150     }
 151
 152   if (unlinkat (dir_fd, "another-file", 0) != 0)
 153     {
 154       puts ("unlinkat failed");
 155       return 1;
 156     }
 157   if (unlinkat (dir_fd, "some-file", 0) != 0)
 158     {
 159       puts ("2nd unlinkat failed");
 160       return 1;
 161     }
 162
 163   close (dir_fd);
 164
 165   return 0;
 166 }