compiler/clib/readlink.c

   1 /*
   2     Copyright © 1995-2012, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     ANSI C function readlink().
   6 */
   7
   8 #include <aros/debug.h>
   9
  10 #include <proto/dos.h>
  11
  12 #include <errno.h>
  13
  14 #include "__arosc_privdata.h"
  15 #include "__errno.h"
  16 #include "__filesystem_support.h"
  17 #include "__upath.h"
  18
  19 /*****************************************************************************
  20
  21     NAME */
  22 #include <unistd.h>
  23
  24         ssize_t readlink(
  25
  26 /*  SYNOPSIS */
  27         const char *path,
  28         char       *buf,
  29         size_t      bufsize)
  30
  31 /*  FUNCTION
  32         Places the contents of a symbolic link in a buffer of given size. No NUL
  33         char is appended to the buffer.
  34
  35     INPUTS
  36         path    - the path to the symbolic link
  37         buf     - pointer to the buffer where to store the symbolic link content
  38         bufsize - the size of the buffer in bytes
  39
  40     RESULT
  41         The call returns the count of characters placed in the buffer if it
  42         succeeds, or a -1 if an error occurs, placing the error code in the
  43         global variable errno.
  44 */
  45 {
  46     struct aroscbase *aroscbase = __GM_GetBase();
  47     ssize_t          res = -1;
  48     struct DevProc   *dvp = NULL;
  49     LONG             error;
  50     struct Process   *me = (struct Process *)FindTask(NULL);
  51
  52     /* check for empty path before potential conversion from "." to "" */
  53     if (aroscbase->acb_doupath && path && *path == '\0')
  54     {
  55         errno = ENOENT;
  56         return res;
  57     }
  58
  59     path = __path_u2a(path);
  60     if (path == NULL)
  61         return res;
  62
  63     res = ReadLink(dvp->dvp_Port, dvp->dvp_Lock, path, buf, bufsize);
  64     if (res == -1) {
  65         error = IoErr();
  66     } else {
  67         if (res == -2)
  68             res = bufsize;
  69         error = me->pr_Result2 = 0;
  70     }
  71
  72     FreeDeviceProc(dvp);
  73
  74     if (error)
  75         errno = IoErr2errno(error);
  76
  77     return res;
  78 }