/****************************************************************************** * $Id: ogrvrtlayer.cpp 10646 2007-01-18 02:38:10Z warmerdam $ * * Project:  OpenGIS Simple Features Reference Implementation * Purpose:  Implements OGRVRTLayer 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 "cpl_conv.h"#include "ogr_vrt.h"#include "cpl_string.h"#include <string>CPL_CVSID("$Id: ogrvrtlayer.cpp 10646 2007-01-18 02:38:10Z warmerdam $");typedef struct {    OGRwkbGeometryType  eType;    const char          *pszName;} OGRGeomTypeName;static OGRGeomTypeName asGeomTypeNames[] = { /* 25D versions are implicit */    { wkbUnknown, "wkbUnknown" },    { wkbPoint, "wkbPoint" },    { wkbLineString, "wkbLineString" },    { wkbPolygon, "wkbPolygon" },    { wkbMultiPoint, "wkbMultiPoint" },    { wkbMultiLineString, "wkbLineString" },    { wkbMultiPolygon, "wkbPolygon" },    { wkbGeometryCollection, "wkbGeometryCollection" },    { wkbNone, "wkbNone" },    { wkbLinearRing, "wkbLinearRing" },    { wkbNone, NULL }};/************************************************************************//*                            OGRVRTLayer()                             *//************************************************************************/OGRVRTLayer::OGRVRTLayer(){    poFeatureDefn = NULL;    poSrcLayer = NULL;    poSRS = NULL;    bUseSpatialSubquery = FALSE;    iFIDField = -1;    eGeometryType = VGS_Direct;    iGeomField = iGeomXField = iGeomYField = iGeomZField = -1;    pszAttrFilter = NULL;    panSrcField = NULL;    pabDirectCopy = NULL;    bNeedReset = TRUE;    bSrcLayerFromSQL = FALSE;    bSrcClip = FALSE;    poSrcRegion = NULL;}/************************************************************************//*                            ~OGRVRTLayer()                            *//************************************************************************/OGRVRTLayer::~OGRVRTLayer(){    if( m_nFeaturesRead > 0 && poFeatureDefn != NULL )    {        CPLDebug( "VRT", "%d features read on layer '%s'.",                  (int) m_nFeaturesRead,                   poFeatureDefn->GetName() );    }    if( poSRS != NULL )        poSRS->Release();    if( poSrcDS != NULL )    {        if( bSrcLayerFromSQL && poSrcLayer )            poSrcDS->ReleaseResultSet( poSrcLayer );        OGRSFDriverRegistrar::GetRegistrar()->ReleaseDataSource( poSrcDS );    }    if( poFeatureDefn )        poFeatureDefn->Release();    CPLFree( panSrcField );    CPLFree( pabDirectCopy );    CPLFree( pszAttrFilter );    if( poSrcRegion != NULL )        delete poSrcRegion;}/************************************************************************//*                             Initialize()                             *//************************************************************************/int OGRVRTLayer::Initialize( CPLXMLNode *psLTree, const char *pszVRTDirectory ){        if( !EQUAL(psLTree->pszValue,"OGRVRTLayer") )        return FALSE;/* -------------------------------------------------------------------- *//*      Get layer name.                                                 *//* -------------------------------------------------------------------- */    const char *pszLayerName = CPLGetXMLValue( psLTree, "name", NULL );    if( pszLayerName == NULL )    {        CPLError( CE_Failure, CPLE_AppDefined,                   "Missing name attribute on OGRVRTLayer" );        return FALSE;    }    poFeatureDefn = new OGRFeatureDefn( pszLayerName );    poFeatureDefn->Reference();/* -------------------------------------------------------------------- *//*      Figure out the data source name.  It may be treated relative    *//*      to vrt filename, but normally it is used directly.              *//* -------------------------------------------------------------------- */    OGRSFDriverRegistrar *poReg = OGRSFDriverRegistrar::GetRegistrar();    char *pszSrcDSName = (char *) CPLGetXMLValue(psLTree,"SrcDataSource",NULL);    if( pszSrcDSName == NULL )    {        CPLError( CE_Failure, CPLE_AppDefined,                   "Missing SrcDataSource for layer %s.", pszLayerName );        return FALSE;    }    if( atoi(CPLGetXMLValue( psLTree, "SrcDataSource.relativetoVRT", "0")) )    {        pszSrcDSName = CPLStrdup(            CPLProjectRelativeFilename( pszVRTDirectory, pszSrcDSName ) );    }    else    {        pszSrcDSName = CPLStrdup(pszSrcDSName);    }/* -------------------------------------------------------------------- *//*      Try to access the datasource.                                   *//* -------------------------------------------------------------------- */    CPLErrorReset();    poSrcDS = poReg->OpenShared( pszSrcDSName, FALSE, NULL );    if( poSrcDS == NULL )     {        if( strlen(CPLGetLastErrorMsg()) == 0 )            CPLError( CE_Failure, CPLE_AppDefined,                       "Failed to open datasource `%s'.",                       pszSrcDSName );        CPLFree( pszSrcDSName );        return FALSE;    }/* -------------------------------------------------------------------- *//*      Is this layer derived from an SQL query result?                 *//* -------------------------------------------------------------------- */    const char *pszSQL = CPLGetXMLValue( psLTree, "SrcSQL", NULL );    if( pszSQL != NULL )    {        poSrcLayer = poSrcDS->ExecuteSQL( pszSQL, NULL, NULL );        if( poSrcLayer == NULL )        {            CPLError( CE_Failure, CPLE_AppDefined,                      "SQL statement failed, or returned no layer result:\n%s",                      pszSQL );					                  return FALSE;        }        bSrcLayerFromSQL = TRUE;    }/* -------------------------------------------------------------------- *//*      Fetch the layer if it is a regular layer.                       *//* -------------------------------------------------------------------- */    if( poSrcLayer == NULL )    {        const char *pszSrcLayerName = CPLGetXMLValue( psLTree, "SrcLayer",                                                       pszLayerName );                poSrcLayer = poSrcDS->GetLayerByName( pszSrcLayerName );        if( poSrcLayer == NULL )        {            CPLError( CE_Failure, CPLE_AppDefined,                  "Failed to find layer '%s' on datasource '%s'.",                       pszSrcLayerName, pszSrcDSName );            CPLFree( pszSrcDSName );            return FALSE;        }    }            CPLFree( pszSrcDSName );/* -------------------------------------------------------------------- *//*      Do we have a fixed geometry type?  If so use it, otherwise      *//*      derive from the source layer.                                   *//* -------------------------------------------------------------------- */     const char *pszGType = CPLGetXMLValue( psLTree, "GeometryType", NULL );          if( pszGType != NULL )     {         int iType;         for( iType = 0; asGeomTypeNames[iType].pszName != NULL; iType++ )         {             if( EQUALN(pszGType, asGeomTypeNames[iType].pszName,                         strlen(asGeomTypeNames[iType].pszName)) )             {                 poFeatureDefn->SetGeomType( asGeomTypeNames[iType].eType );                 if( strstr(pszGType,"25D") != NULL )                     poFeatureDefn->SetGeomType(                          (OGRwkbGeometryType)                         (poFeatureDefn->GetGeomType() | wkb25DBit) );                 break;             }         }         if( asGeomTypeNames[iType].pszName == NULL )         {             CPLError( CE_Failure, CPLE_AppDefined,                        "GeometryType %s not recognised.",                        pszGType );             return FALSE;         }     }     else     {         poFeatureDefn->SetGeomType(poSrcLayer->GetLayerDefn()->GetGeomType());     }     /* -------------------------------------------------------------------- *//*      For now we copy the schema directly from the source layer.      *//* -------------------------------------------------------------------- */     int iField;     OGRFeatureDefn *poSrcDefn = poSrcLayer->GetLayerDefn();     panSrcField = (int *) CPLMalloc(sizeof(int) * poSrcDefn->GetFieldCount());     pabDirectCopy = (int *) CPLMalloc(sizeof(int)*poSrcDefn->GetFieldCount());     for( iField = 0; iField < poSrcDefn->GetFieldCount(); iField++ )     {         poFeatureDefn->AddFieldDefn( poSrcDefn->GetFieldDefn( iField ) );         panSrcField[iField] = iField;         pabDirectCopy[iField] = TRUE;     }     /* -------------------------------------------------------------------- *//*      Apply a spatial reference system if provided, otherwise copy    *//*      from source.                                                    *//* -------------------------------------------------------------------- */     const char *pszLayerSRS = CPLGetXMLValue( psLTree, "LayerSRS", NULL );     if( pszLayerSRS != NULL )     {         if( EQUAL(pszLayerSRS,"NULL") )             poSRS = NULL;         else         {             OGRSpatialReference oSRS;             if( oSRS.SetFromUserInput( pszLayerSRS ) != OGRERR_NONE )             {                 CPLError( CE_Failure, CPLE_AppDefined,                            "Failed to import LayerSRS `%s'.", pszLayerSRS );                 return FALSE;             }             poSRS = oSRS.Clone();         }     }     else     {         if( poSrcLayer->GetSpatialRef() != NULL )             poSRS = poSrcLayer->GetSpatialRef()->Clone();         else             poSRS = NULL;     }/* -------------------------------------------------------------------- *//*      Handle GeometryField.                                           *//* -------------------------------------------------------------------- */     const char *pszEncoding;     pszEncoding = CPLGetXMLValue( psLTree,"GeometryField.encoding", "direct");     if( EQUAL(pszEncoding,"Direct") )         eGeometryType = VGS_Direct;     else if( EQUAL(pszEncoding,"None") )         eGeometryType = VGS_None;     else if( EQUAL(pszEncoding,"WKT") )         eGeometryType = VGS_WKT;     else if( EQUAL(pszEncoding,"WKB") )         eGeometryType = VGS_WKB;     else if( EQUAL(pszEncoding,"Shape") )         eGeometryType = VGS_Shape;     else if( EQUAL(pszEncoding,"PointFromColumns") )     {         eGeometryType = VGS_PointFromColumns;         bUseSpatialSubquery =              CSLTestBoolean(                 CPLGetXMLValue(psLTree,                                 "GeometryField.useSpatialSubquery",                                "TRUE"));         iGeomXField = poSrcLayer->GetLayerDefn()->GetFieldIndex(             CPLGetXMLValue( psLTree, "GeometryField.x", "missing" ) );         iGeomYField = poSrcLayer->GetLayerDefn()->GetFieldIndex(             CPLGetXMLValue( psLTree, "GeometryField.y", "missing" ) );         iGeomZField = poSrcLayer->GetLayerDefn()->GetFieldIndex(             CPLGetXMLValue( psLTree, "GeometryField.z", "missing" ) );         if( iGeomXField == -1 || iGeomYField == -1 )         {             CPLError( CE_Failure, CPLE_AppDefined,                        "Unable to identify source X or Y field for PointFromColumns encoding." );             return FALSE;         }     }     else     {         CPLError( CE_Failure, CPLE_AppDefined,                    "encoding=\"%s\" not recognised.", pszEncoding );         return FALSE;     }     if( eGeometryType == VGS_WKT          || eGeometryType == VGS_WKB          || eGeometryType == VGS_Shape )     {         const char *pszFieldName =              CPLGetXMLValue( psLTree, "GeometryField.field", "missing" );         iGeomField = poSrcLayer->GetLayerDefn()->GetFieldIndex(pszFieldName);         if( iGeomField == -1 )         {             CPLError( CE_Failure, CPLE_AppDefined,                        "Unable to identify source field '%s' for geometry.",                       pszFieldName );             return FALSE;         }     }                                               /* -------------------------------------------------------------------- *//*      Figure out what should be used as an FID.                       */