/****************************************************************************** * $Id: ogrvrtdriver.cpp 10646 2007-01-18 02:38:10Z warmerdam $ * * Project:  OpenGIS Simple Features Reference Implementation * Purpose:  Implements OGRVRTDriver class. * Author:   Frank Warmerdam, warmerdam@pobox.com * ****************************************************************************** * Copyright (c) 2003, Frank Warmerdam <warmerdam@pobox.com> * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. ****************************************************************************/#include "ogr_vrt.h"#include "cpl_conv.h"CPL_CVSID("$Id: ogrvrtdriver.cpp 10646 2007-01-18 02:38:10Z warmerdam $");/************************************************************************//*                            ~OGRVRTDriver()                            *//************************************************************************/OGRVRTDriver::~OGRVRTDriver(){}/************************************************************************//*                              GetName()                               *//************************************************************************/const char *OGRVRTDriver::GetName(){    return "VRT";}/************************************************************************//*                                Open()                                *//************************************************************************/OGRDataSource *OGRVRTDriver::Open( const char * pszFilename,                                     int bUpdate ){    OGRVRTDataSource     *poDS;    char *pszXML = NULL;/* -------------------------------------------------------------------- *//*      Are we being passed the XML definition directly?                *//* -------------------------------------------------------------------- */    if( EQUALN(pszFilename,"<OGRVRTDataSource>",18) )    {        pszXML = CPLStrdup(pszFilename);    }/* -------------------------------------------------------------------- *//*      Open file and check if it contains appropriate XML.             *//* -------------------------------------------------------------------- */    else    {        FILE *fp;        char achHeader[18];        fp = VSIFOpen( pszFilename, "rb" );        if( fp == NULL )            return NULL;        if( VSIFRead( achHeader, sizeof(achHeader), 1, fp ) != 1 )        {            VSIFClose( fp );            return NULL;        }        if( !EQUALN(achHeader,"<OGRVRTDataSource>",18) )        {            VSIFClose( fp );            return NULL;        }/* -------------------------------------------------------------------- *//*      It is the right file, now load the full XML definition.         *//* -------------------------------------------------------------------- */        int nLen;        VSIFSeek( fp, 0, SEEK_END );        nLen = VSIFTell( fp );        VSIFSeek( fp, 0, SEEK_SET );                pszXML = (char *) CPLMalloc(nLen+1);        pszXML[nLen] = '\0';        if( ((int) VSIFRead( pszXML, 1, nLen, fp )) != nLen )        {            CPLFree( pszXML );            VSIFClose( fp );            return NULL;        }        VSIFClose( fp );    }/* -------------------------------------------------------------------- *//*      We don't allow update access at this time through VRT           *//*      datasources.                                                    *//* -------------------------------------------------------------------- */    if( bUpdate )    {        CPLFree( pszXML );        CPLError( CE_Failure, CPLE_OpenFailed,                   "Update access not supported for VRT datasources." );        return NULL;    }/* -------------------------------------------------------------------- *//*      Parse the XML.                                                  *//* -------------------------------------------------------------------- */    CPLXMLNode *psTree = CPLParseXMLString( pszXML );    CPLFree( pszXML );    if( psTree == NULL )        return NULL;/* -------------------------------------------------------------------- *//*      Create a virtual datasource configured based on this XML input. *//* -------------------------------------------------------------------- */    poDS = new OGRVRTDataSource();    if( !poDS->Initialize( psTree, pszFilename ) )    {        CPLDestroyXMLNode( psTree );        delete poDS;        return NULL;    }    CPLDestroyXMLNode( psTree );    return poDS;}/************************************************************************//*                           TestCapability()                           *//************************************************************************/int OGRVRTDriver::TestCapability( const char * pszCap ){    return FALSE;}/************************************************************************//*                           RegisterOGRVRT()                           *//************************************************************************/void RegisterOGRVRT(){    OGRSFDriverRegistrar::GetRegistrar()->RegisterDriver( new OGRVRTDriver );}