usr/src/lib/libast/common/comp/symlink.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23
  24 #include <ast.h>
  25
  26 #if _lib_symlink
  27
  28 NoN(symlink)
  29
  30 #else
  31
  32 #include "fakelink.h"
  33
  34 #include <error.h>
  35
  36 #ifndef ENOSYS
  37 #define ENOSYS  EINVAL
  38 #endif
  39
  40 int
  41 symlink(const char* a, char* b)
  42 {
  43         if (*a == '/' && (*(a + 1) == 'd' || *(a + 1) == 'p' || *(a + 1) == 'n') && (!strncmp(a, "/dev/tcp/", 9) || !strncmp(a, "/dev/udp/", 9) || !strncmp(a, "/proc/", 6) || !strncmp(a, "/n/", 3)))
  44         {
  45                 int     n;
  46                 int     fd;
  47
  48                 if ((fd = open(b, O_CREAT|O_TRUNC|O_WRONLY, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)) < 0)
  49                         return -1;
  50                 n = strlen(a) + 1;
  51                 n = (write(fd, FAKELINK_MAGIC, sizeof(FAKELINK_MAGIC)) != sizeof(FAKELINK_MAGIC) || write(fd, a, n) != n) ? -1 : 0;
  52                 close(fd);
  53                 return n;
  54         }
  55         errno = ENOSYS;
  56         return -1;
  57 }
  58
  59 #endif