/* $Header: /cvs/maptools/cvsroot/libtiff/libtiff/tif_extension.c,v 1.4 2004/10/02 13:29:41 dron Exp $ *//* * Copyright (c) 1988-1997 Sam Leffler * Copyright (c) 1991-1997 Silicon Graphics, Inc. * * Permission to use, copy, modify, distribute, and sell this software and  * its documentation for any purpose is hereby granted without fee, provided * that (i) the above copyright notices and this permission notice appear in * all copies of the software and related documentation, and (ii) the names of * Sam Leffler and Silicon Graphics may not be used in any advertising or * publicity relating to the software without the specific, prior written * permission of Sam Leffler and Silicon Graphics. *  * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,  * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.   *  * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF  * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE  * OF THIS SOFTWARE. *//* * TIFF Library. * * Various routines support external extension of the tag set, and other * application extension capabilities.  */#include "tiffiop.h"int TIFFGetTagListCount( TIFF *tif ){    TIFFDirectory* td = &tif->tif_dir;        return td->td_customValueCount;}ttag_t TIFFGetTagListEntry( TIFF *tif, int tag_index ){    TIFFDirectory* td = &tif->tif_dir;    if( tag_index < 0 || tag_index >= td->td_customValueCount )        return (ttag_t) -1;    else        return td->td_customValues[tag_index].info->field_tag;}/*** This provides read/write access to the TIFFTagMethods within the TIFF** structure to application code without giving access to the private** TIFF structure.*/TIFFTagMethods *TIFFAccessTagMethods( TIFF *tif ){    return &(tif->tif_tagmethods);}void *TIFFGetClientInfo( TIFF *tif, const char *name ){    TIFFClientInfoLink *link = tif->tif_clientinfo;    while( link != NULL && strcmp(link->name,name) != 0 )        link = link->next;    if( link != NULL )        return link->data;    else        return NULL;}void TIFFSetClientInfo( TIFF *tif, void *data, const char *name ){    TIFFClientInfoLink *link = tif->tif_clientinfo;    /*    ** Do we have an existing link with this name?  If so, just    ** set it.    */    while( link != NULL && strcmp(link->name,name) != 0 )        link = link->next;    if( link != NULL )    {        link->data = data;        return;    }    /*    ** Create a new link.    */    link = (TIFFClientInfoLink *) _TIFFmalloc(sizeof(TIFFClientInfoLink));    assert (link != NULL);    link->next = tif->tif_clientinfo;    link->name = (char *) _TIFFmalloc(strlen(name)+1);    assert (link->name != NULL);    strcpy(link->name, name);    link->data = data;    tif->tif_clientinfo = link;}