ogrvrtdatasource.cpp

GIS系统支持库Geospatial Data Abstraction Library代码.GDAL is a translator library for raster geospatial dat

/******************************************************************************
 * $Id: ogrvrtdatasource.cpp,v 1.2 2003/11/07 21:55:12 warmerda Exp $
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  Implements OGRVRTDataSource class.
 * Author:   Frank Warmerdam, [e-mail]
 *
 ******************************************************************************
 * Copyright (c) 2003, Frank Warmerdam <[e-mail]>
 *
 * 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.
 ******************************************************************************
 *
 * $Log: ogrvrtdatasource.cpp,v $
 * Revision 1.2  2003/11/07 21:55:12  warmerda
 * complete fid support, relative dsname, fixes
 *
 * Revision 1.1  2003/11/07 17:50:36  warmerda
 * New
 *
 */

#include "ogr_vrt.h"
#include "cpl_conv.h"
#include "cpl_string.h"

CPL_CVSID("$Id: ogrvrtdatasource.cpp,v 1.2 2003/11/07 21:55:12 warmerda Exp $");
/************************************************************************/
/*                          OGRVRTDataSource()                          */
/************************************************************************/

OGRVRTDataSource::OGRVRTDataSource()

{
    pszName = NULL;
    papoLayers = NULL;
    nLayers = 0;
}

/************************************************************************/
/*                         ~OGRVRTDataSource()                         */
/************************************************************************/

OGRVRTDataSource::~OGRVRTDataSource()

{
    int         i;

    CPLFree( pszName );

    for( i = 0; i < nLayers; i++ )
        delete papoLayers[i];
    
    CPLFree( papoLayers );
}

/************************************************************************/
/*                             Initialize()                             */
/************************************************************************/

int OGRVRTDataSource::Initialize( CPLXMLNode *psTree, const char *pszNewName )

{
    CPLAssert( nLayers == 0 );

/* -------------------------------------------------------------------- */
/*      Set name, and capture the directory path so we can use it       */
/*      for relative datasources.                                       */
/* -------------------------------------------------------------------- */
    char *pszVRTDirectory = CPLStrdup( CPLGetPath( pszNewName ) );

    pszName = CPLStrdup( pszNewName );

/* -------------------------------------------------------------------- */
/*      Look for layers.                                                */
/* -------------------------------------------------------------------- */
    CPLXMLNode *psLTree;

    for( psLTree=psTree->psChild; psLTree != NULL; psLTree=psLTree->psNext )
    {
        if( psLTree->eType != CXT_Element
            || !EQUAL(psLTree->pszValue,"OGRVRTLayer") )
            continue;

/* -------------------------------------------------------------------- */
/*      Create the layer object.                                        */
/* -------------------------------------------------------------------- */
        OGRVRTLayer  *poLayer;
        
        poLayer = new OGRVRTLayer();
        
        if( !poLayer->Initialize( psLTree, pszVRTDirectory ) )
        {
            CPLFree( pszVRTDirectory );
            delete poLayer;
            return FALSE;
        }
        
/* -------------------------------------------------------------------- */
/*      Add layer to data source layer list.                            */
/* -------------------------------------------------------------------- */
        papoLayers = (OGRVRTLayer **)
            CPLRealloc( papoLayers,  sizeof(OGRVRTLayer *) * (nLayers+1) );
        papoLayers[nLayers++] = poLayer;
    }

    CPLFree( pszVRTDirectory );
    return TRUE;
}

/************************************************************************/
/*                           TestCapability()                           */
/************************************************************************/

int OGRVRTDataSource::TestCapability( const char * pszCap )

{
    return FALSE;
}

/************************************************************************/
/*                              GetLayer()                              */
/************************************************************************/

OGRLayer *OGRVRTDataSource::GetLayer( int iLayer )

{
    if( iLayer < 0 || iLayer >= nLayers )
        return NULL;
    else
        return papoLayers[iLayer];
}