OGRDataSource *OGRVRTDriver::Open( const char * pszFilename,
int bUpdate )
{
OGRVRTDataSource *poDS;
char *pszXML = NULL;
/* -------------------------------------------------------------------- */
/* Are we being passed the XML definition directly? */
/* Skip any leading spaces/blanks. */
/* -------------------------------------------------------------------- */
const char *pszTestXML = pszFilename;
while( *pszTestXML != '\0' && isspace( (unsigned char)*pszTestXML ) )
pszTestXML++;
if( EQUALN(pszTestXML,"<OGRVRTDataSource>",18) )
{
pszXML = CPLStrdup(pszTestXML);
}
/* -------------------------------------------------------------------- */
/* Open file and check if it contains appropriate XML. */
/* -------------------------------------------------------------------- */
else
{
VSILFILE *fp;
char achHeader[512];
fp = VSIFOpenL( pszFilename, "rb" );
if( fp == NULL )
return NULL;
memset( achHeader, 0, sizeof(achHeader) );
VSIFReadL( achHeader, 1, sizeof(achHeader)-1, fp );
if( strstr(achHeader,"<OGRVRTDataSource") == NULL )
{
VSIFCloseL( fp );
return NULL;
}
VSIStatBufL sStatBuf;
if ( VSIStatL( pszFilename, &sStatBuf ) != 0 ||
sStatBuf.st_size > 1024 * 1024 )
{
CPLDebug( "VRT", "Unreasonable long file, not likely really VRT" );
VSIFCloseL( fp );
return NULL;
}
/* -------------------------------------------------------------------- */
/* It is the right file, now load the full XML definition. */
/* -------------------------------------------------------------------- */
int nLen = (int) sStatBuf.st_size;
VSIFSeekL( fp, 0, SEEK_SET );
pszXML = (char *) VSIMalloc(nLen+1);
if (pszXML == NULL)
{
VSIFCloseL( fp );
return NULL;
}
pszXML[nLen] = '\0';
if( ((int) VSIFReadL( pszXML, 1, nLen, fp )) != nLen )
{
CPLFree( pszXML );
VSIFCloseL( fp );
return NULL;
}
VSIFCloseL( fp );
}
/* -------------------------------------------------------------------- */
/* Parse the XML. */
/* -------------------------------------------------------------------- */
CPLXMLNode *psTree = CPLParseXMLString( pszXML );
if( psTree == NULL )
{
CPLFree( pszXML );
return NULL;
}
/* -------------------------------------------------------------------- */
/* XML Validation. */
/* -------------------------------------------------------------------- */
if( CSLTestBoolean(CPLGetConfigOption("GDAL_XML_VALIDATION", "YES")) )
{
const char* pszXSD = CPLFindFile( "gdal", "ogrvrt.xsd" );
if( pszXSD != NULL )
{
std::vector<CPLString> aosErrors;
CPLPushErrorHandlerEx(OGRVRTErrorHandler, &aosErrors);
int bRet = CPLValidateXML(pszXML, pszXSD, NULL);
CPLPopErrorHandler();
if( !bRet )
{
if( aosErrors.size() > 0 &&
strstr(aosErrors[0].c_str(), "missing libxml2 support") == NULL )
{
for(size_t i = 0; i < aosErrors.size(); i++)
{
CPLError(CE_Warning, CPLE_AppDefined, "%s", aosErrors[i].c_str());
}
}
}
CPLErrorReset();
}
}
CPLFree( pszXML );
/* -------------------------------------------------------------------- */
/* Create a virtual datasource configured based on this XML input. */
/* -------------------------------------------------------------------- */
poDS = new OGRVRTDataSource();
poDS->SetDriver(this);
/* psTree is owned by poDS */
if( !poDS->Initialize( psTree, pszFilename, bUpdate ) )
{
delete poDS;
return NULL;
}
return poDS;
}
OGRDataSource *OGRVRTDriver::Open( const char * pszFilename,
int bUpdate )
{
OGRVRTDataSource *poDS;
char *pszXML = NULL;
/* -------------------------------------------------------------------- */
/* Are we being passed the XML definition directly? */
/* Skip any leading spaces/blanks. */
/* -------------------------------------------------------------------- */
const char *pszTestXML = pszFilename;
while( *pszTestXML != '\0' && isspace( (unsigned char)*pszTestXML ) )
pszTestXML++;
if( EQUALN(pszTestXML,"<OGRVRTDataSource>",18) )
{
pszXML = CPLStrdup(pszTestXML);
}
/* -------------------------------------------------------------------- */
/* Open file and check if it contains appropriate XML. */
/* -------------------------------------------------------------------- */
else
{
FILE *fp;
char achHeader[18];
fp = VSIFOpenL( pszFilename, "rb" );
if( fp == NULL )
return NULL;
if( VSIFReadL( achHeader, sizeof(achHeader), 1, fp ) != 1 )
{
VSIFCloseL( fp );
return NULL;
}
if( !EQUALN(achHeader,"<OGRVRTDataSource>",18) )
{
VSIFCloseL( fp );
return NULL;
}
/* -------------------------------------------------------------------- */
/* It is the right file, now load the full XML definition. */
/* -------------------------------------------------------------------- */
int nLen;
VSIFSeekL( fp, 0, SEEK_END );
nLen = (int) VSIFTellL( fp );
VSIFSeekL( fp, 0, SEEK_SET );
pszXML = (char *) VSIMalloc(nLen+1);
if (pszXML == NULL)
{
VSIFCloseL( fp );
return NULL;
}
pszXML[nLen] = '\0';
if( ((int) VSIFReadL( pszXML, 1, nLen, fp )) != nLen )
{
CPLFree( pszXML );
VSIFCloseL( fp );
return NULL;
}
VSIFCloseL( fp );
}
/* -------------------------------------------------------------------- */
/* 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, bUpdate ) )
{
CPLDestroyXMLNode( psTree );
delete poDS;
return NULL;
}
CPLDestroyXMLNode( psTree );
return poDS;
}
