compiler/clib/symlink.c

   1 /*
   2     Copyright © 2004, 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 "__errno.h"
  14 #include "__upath.h"
  15 #include <aros/debug.h>
  16
  17 /*****************************************************************************
  18
  19     NAME */
  20 #include <unistd.h>
  21
  22         int symlink(
  23
  24 /*  SYNOPSIS */
  25         const char *oldpath,
  26         const char *newpath)
  27
  28 /*  FUNCTION
  29
  30     INPUTS
  31
  32     RESULT
  33
  34     NOTES
  35
  36     EXAMPLE
  37
  38     BUGS
  39
  40     SEE ALSO
  41
  42     INTERNALS
  43
  44 ******************************************************************************/
  45 {
  46     int retval = -1;
  47     BPTR lock;
  48     LONG ioerr = 0;
  49     UBYTE *buffer;
  50     int buffersize = 256;
  51
  52     if (!oldpath || !newpath) /*safety check */
  53     {
  54         errno = EFAULT;
  55         return -1;
  56     }
  57
  58     oldpath = __path_u2a(oldpath);
  59     if(!oldpath)
  60         return -1;
  61
  62     oldpath = strdup(oldpath);
  63     if(!oldpath)
  64     {
  65         errno = ENOMEM;
  66         return -1;
  67     }
  68
  69     newpath = __path_u2a(newpath);
  70     if (!newpath)
  71     {
  72         free((void*) oldpath);
  73         return -1;
  74     }
  75
  76     if((lock = Lock((STRPTR)oldpath, SHARED_LOCK)))
  77     {
  78         do
  79         {
  80             if(!(buffer = AllocVec(buffersize, MEMF_ANY)))
  81             {
  82                 ioerr = ERROR_NO_FREE_STORE;
  83                 break;
  84             }
  85
  86             /* Get the full path of oldpath */
  87             if(NameFromLock(lock, buffer, buffersize))
  88             {
  89                 if(MakeLink((STRPTR)newpath, (STRPTR)buffer, TRUE))
  90                     retval = 0;
  91                 else
  92                 {
  93                     ioerr = IoErr();
  94                     FreeVec(buffer);
  95                     break;
  96                 }
  97             }
  98             else if(IoErr() != ERROR_LINE_TOO_LONG)
  99             {
 100                 ioerr = IoErr();
 101                 FreeVec(buffer);
 102                 break;
 103             }
 104             FreeVec(buffer);
 105             buffersize *= 2;
 106         }
 107         while(retval != RETURN_OK);
 108         UnLock(lock);
 109     }
 110     else
 111     {
 112         /* MakeLink can create symlinks to non-existing files or
 113            directories. */
 114         if(IoErr() == ERROR_OBJECT_NOT_FOUND)
 115         {
 116             /* In this case it may be difficult to get the full absolute
 117                path, so we simply trust the caller here for now */
 118             if(MakeLink((STRPTR)newpath, (STRPTR)oldpath, TRUE))
 119                 retval = 0;
 120             else
 121                 ioerr = IoErr();
 122         }
 123         else
 124             ioerr = IoErr();
 125     }
 126     free((void*) oldpath);
 127
 128     if(ioerr)
 129         errno = IoErr2errno(ioerr);
 130
 131     return retval;
 132 } /* symlink */
 133