1                 : /* $Header: /cvs/maptools/cvsroot/libtiff/libtiff/tif_extension.c,v 1.7 2010-03-10 18:56:48 bfriesen Exp $ */
       2                 : 
       3                 : /*
       4                 :  * Copyright (c) 1988-1997 Sam Leffler
       5                 :  * Copyright (c) 1991-1997 Silicon Graphics, Inc.
       6                 :  *
       7                 :  * Permission to use, copy, modify, distribute, and sell this software and 
       8                 :  * its documentation for any purpose is hereby granted without fee, provided
       9                 :  * that (i) the above copyright notices and this permission notice appear in
      10                 :  * all copies of the software and related documentation, and (ii) the names of
      11                 :  * Sam Leffler and Silicon Graphics may not be used in any advertising or
      12                 :  * publicity relating to the software without the specific, prior written
      13                 :  * permission of Sam Leffler and Silicon Graphics.
      14                 :  * 
      15                 :  * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, 
      16                 :  * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY 
      17                 :  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  
      18                 :  * 
      19                 :  * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
      20                 :  * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
      21                 :  * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
      22                 :  * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF 
      23                 :  * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 
      24                 :  * OF THIS SOFTWARE.
      25                 :  */
      26                 : 
      27                 : /*
      28                 :  * TIFF Library.
      29                 :  *
      30                 :  * Various routines support external extension of the tag set, and other
      31                 :  * application extension capabilities. 
      32                 :  */
      33                 : 
      34                 : #include "tiffiop.h"
      35                 : 
      36                 : int TIFFGetTagListCount( TIFF *tif )
      37                 : 
      38               0 : {
      39               0 :     TIFFDirectory* td = &tif->tif_dir;
      40                 :     
      41               0 :     return td->td_customValueCount;
      42                 : }
      43                 : 
      44                 : uint32 TIFFGetTagListEntry( TIFF *tif, int tag_index )
      45                 : 
      46               0 : {
      47               0 :     TIFFDirectory* td = &tif->tif_dir;
      48                 : 
      49               0 :     if( tag_index < 0 || tag_index >= td->td_customValueCount )
      50               0 :         return (uint32)(-1);
      51                 :     else
      52               0 :         return td->td_customValues[tag_index].info->field_tag;
      53                 : }
      54                 : 
      55                 : /*
      56                 : ** This provides read/write access to the TIFFTagMethods within the TIFF
      57                 : ** structure to application code without giving access to the private
      58                 : ** TIFF structure.
      59                 : */
      60                 : TIFFTagMethods *TIFFAccessTagMethods( TIFF *tif )
      61                 : 
      62               0 : {
      63               0 :     return &(tif->tif_tagmethods);
      64                 : }
      65                 : 
      66                 : void *TIFFGetClientInfo( TIFF *tif, const char *name )
      67                 : 
      68               0 : {
      69               0 :     TIFFClientInfoLink *link = tif->tif_clientinfo;
      70                 : 
      71               0 :     while( link != NULL && strcmp(link->name,name) != 0 )
      72               0 :         link = link->next;
      73                 : 
      74               0 :     if( link != NULL )
      75               0 :         return link->data;
      76                 :     else
      77               0 :         return NULL;
      78                 : }
      79                 : 
      80                 : void TIFFSetClientInfo( TIFF *tif, void *data, const char *name )
      81                 : 
      82               0 : {
      83               0 :     TIFFClientInfoLink *link = tif->tif_clientinfo;
      84                 : 
      85                 :     /*
      86                 :     ** Do we have an existing link with this name?  If so, just
      87                 :     ** set it.
      88                 :     */
      89               0 :     while( link != NULL && strcmp(link->name,name) != 0 )
      90               0 :         link = link->next;
      91                 : 
      92               0 :     if( link != NULL )
      93                 :     {
      94               0 :         link->data = data;
      95               0 :         return;
      96                 :     }
      97                 : 
      98                 :     /*
      99                 :     ** Create a new link.
     100                 :     */
     101                 : 
     102               0 :     link = (TIFFClientInfoLink *) _TIFFmalloc(sizeof(TIFFClientInfoLink));
     103               0 :     assert (link != NULL);
     104               0 :     link->next = tif->tif_clientinfo;
     105               0 :     link->name = (char *) _TIFFmalloc((tmsize_t)(strlen(name)+1));
     106               0 :     assert (link->name != NULL);
     107               0 :     strcpy(link->name, name);
     108               0 :     link->data = data;
     109                 : 
     110               0 :     tif->tif_clientinfo = link;
     111                 : }
     112                 : /*
     113                 :  * Local Variables:
     114                 :  * mode: c
     115                 :  * c-basic-offset: 8
     116                 :  * fill-column: 78
     117                 :  * End:
     118                 :  */