compiler/clib/symlink.c

   1 /*
   2     Copyright © 2004-2012, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     POSIX function symlink().
   6 */
   7
   8 #include <aros/debug.h>
   9
  10 #include <stdlib.h>
  11 #include <proto/dos.h>
  12 #include <errno.h>
  13 #include "__upath.h"
  14 #include <aros/debug.h>
  15
  16 /*****************************************************************************
  17
  18     NAME */
  19 #include <unistd.h>
  20
  21         int symlink(
  22
  23 /*  SYNOPSIS */
  24         const char *oldpath,
  25         const char *newpath)
  26
  27 /*  FUNCTION
  28
  29     INPUTS
  30
  31     RESULT
  32
  33     NOTES
  34
  35     EXAMPLE
  36
  37     BUGS
  38
  39     SEE ALSO
  40
  41     INTERNALS
  42
  43 ******************************************************************************/
  44 {
  45     int retval = -1;
  46     BPTR lock;
  47     LONG ioerr = 0;
  48     UBYTE *buffer;
  49     int buffersize = 256;
  50
  51     if (!oldpath || !newpath) /*safety check */
  52     {
  53         errno = EFAULT;
  54         return -1;
  55     }
  56
  57     oldpath = __path_u2a(oldpath);
  58     if(!oldpath)
  59         return -1;
  60
  61     oldpath = strdup(oldpath);
  62     if(!oldpath)
  63     {
  64         errno = ENOMEM;
  65         return -1;
  66     }
  67
  68     newpath = __path_u2a(newpath);
  69     if (!newpath)
  70     {
  71         free((void*) oldpath);
  72         return -1;
  73     }
  74
  75     if((lock = Lock((STRPTR)oldpath, SHARED_LOCK)))
  76     {
  77         do
  78         {
  79             if(!(buffer = AllocVec(buffersize, MEMF_ANY)))
  80             {
  81                 ioerr = ERROR_NO_FREE_STORE;
  82                 break;
  83             }
  84
  85             /* Get the full path of oldpath */
  86             if(NameFromLock(lock, buffer, buffersize))
  87             {
  88                 if(MakeLink((STRPTR)newpath, (STRPTR)buffer, TRUE))
  89                     retval = 0;
  90                 else
  91                 {
  92                     ioerr = IoErr();
  93                     FreeVec(buffer);
  94                     break;
  95                 }
  96             }
  97             else if(IoErr() != ERROR_LINE_TOO_LONG)
  98             {
  99                 ioerr = IoErr();
 100                 FreeVec(buffer);
 101                 break;
 102             }
 103             FreeVec(buffer);
 104             buffersize *= 2;
 105         }
 106         while(retval != RETURN_OK);
 107         UnLock(lock);
 108     }
 109     else
 110     {
 111         /* MakeLink can create symlinks to non-existing files or
 112            directories. */
 113         if(IoErr() == ERROR_OBJECT_NOT_FOUND)
 114         {
 115             /* In this case it may be difficult to get the full absolute
 116                path, so we simply trust the caller here for now */
 117             if(MakeLink((STRPTR)newpath, (STRPTR)oldpath, TRUE))
 118                 retval = 0;
 119             else
 120                 ioerr = IoErr();
 121         }
 122         else
 123             ioerr = IoErr();
 124     }
 125     free((void*) oldpath);
 126
 127     if(ioerr)
 128         errno = __arosc_ioerr2errno(ioerr);
 129
 130     return retval;
 131 } /* symlink */
 132