src/tiff/libtiff/tif_extension.c

   1 /* $Header: /cvs/maptools/cvsroot/libtiff/libtiff/tif_extension.c,v 1.4 2004/10/02 13:29:41 dron 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 {
  39     TIFFDirectory* td = &tif->tif_dir;
  40
  41     return td->td_customValueCount;
  42 }
  43
  44 ttag_t TIFFGetTagListEntry( TIFF *tif, int tag_index )
  45
  46 {
  47     TIFFDirectory* td = &tif->tif_dir;
  48
  49     if( tag_index < 0 || tag_index >= td->td_customValueCount )
  50         return (ttag_t) -1;
  51     else
  52         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 {
  63     return &(tif->tif_tagmethods);
  64 }
  65
  66 void *TIFFGetClientInfo( TIFF *tif, const char *name )
  67
  68 {
  69     TIFFClientInfoLink *link = tif->tif_clientinfo;
  70
  71     while( link != NULL && strcmp(link->name,name) != 0 )
  72         link = link->next;
  73
  74     if( link != NULL )
  75         return link->data;
  76     else
  77         return NULL;
  78 }
  79
  80 void TIFFSetClientInfo( TIFF *tif, void *data, const char *name )
  81
  82 {
  83     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     while( link != NULL && strcmp(link->name,name) != 0 )
  90         link = link->next;
  91
  92     if( link != NULL )
  93     {
  94         link->data = data;
  95         return;
  96     }
  97
  98     /*
  99     ** Create a new link.
 100     */
 101
 102     link = (TIFFClientInfoLink *) _TIFFmalloc(sizeof(TIFFClientInfoLink));
 103     assert (link != NULL);
 104     link->next = tif->tif_clientinfo;
 105     link->name = (char *) _TIFFmalloc(strlen(name)+1);
 106     assert (link->name != NULL);
 107     strcpy(link->name, name);
 108     link->data = data;
 109
 110     tif->tif_clientinfo = link;
 111 }