ogrpglayer.cpp

来自「支持各种栅格图像和矢量图像读取的库」· C++ 代码 · 共 1,045 行 · 第 1/3 页

            int nCount, i;
            double *padfList;

#if !defined(PG_PRE74)
            if ( PQfformat( hCursorResult, iField ) == 1 ) // Binary data representation
            {
                char * pData = PQgetvalue( hCursorResult, iRecord, iField );

                // goto number of array elements
                pData += 3 * sizeof(int);
                memcpy( &nCount, pData, sizeof(int) );
                CPL_MSBPTR32( &nCount );

                padfList = (double *) CPLCalloc(sizeof(double),nCount);

                // goto first array element
                pData += 2 * sizeof(int);

                for( i = 0; i < nCount; i++ )
                {
                    // get element size
                    int nSize = *(int *)(pData);
                    CPL_MSBPTR32( &nSize );

                    CPLAssert( nSize == sizeof(double) );

                    pData += sizeof(int);

                    memcpy( &padfList[i], pData, nSize );
                    CPL_MSBPTR64(&padfList[i]);

                    pData += nSize;
                }
            }
            else
#endif /* notdef PG_PRE74 */
            {
                char **papszTokens;
                papszTokens = CSLTokenizeStringComplex(
                    PQgetvalue( hCursorResult, iRecord, iField ),
                    "{,}", FALSE, FALSE );

                nCount = CSLCount(papszTokens);
                padfList = (double *) CPLCalloc(sizeof(double),nCount);

                for( i = 0; i < nCount; i++ )
                    padfList[i] = atof(papszTokens[i]);
                CSLDestroy( papszTokens );
            }

            poFeature->SetField( iOGRField, nCount, padfList );
            CPLFree( padfList );
        }

        else if( eOGRType == OFTStringList )
        {
            char **papszTokens = 0;

#if !defined(PG_PRE74)
            if ( PQfformat( hCursorResult, iField ) == 1 ) // Binary data representation
            {
                char * pData = PQgetvalue( hCursorResult, iRecord, iField );
                int nCount, i;

                // goto number of array elements
                pData += 3 * sizeof(int);
                memcpy( &nCount, pData, sizeof(int) );
                CPL_MSBPTR32( &nCount );

                // goto first array element
                pData += 2 * sizeof(int);

                for( i = 0; i < nCount; i++ )
                {
                    // get element size
                    int nSize = *(int *)(pData);
                    CPL_MSBPTR32( &nSize );

                    pData += sizeof(int);

                    papszTokens = CSLAddString(papszTokens, pData);

                    pData += nSize;
                }
            }
            else
#endif /* notdef PG_PRE74 */
            {
                papszTokens = CSLTokenizeStringComplex(
                        PQgetvalue( hCursorResult, iRecord, iField ),
                        "{,}", FALSE, FALSE );
            }

            if ( papszTokens )
            {
                poFeature->SetField( iOGRField, papszTokens );
                CSLDestroy( papszTokens );
            }
        }

        else if( eOGRType == OFTDate 
                 || eOGRType == OFTTime 
                 || eOGRType == OFTDateTime )
        {
#if !defined(PG_PRE74)
            if ( PQfformat( hCursorResult, iField ) == 1 ) // Binary data
            {
                CPLDebug( "PG", "Binary DATE format not yet implemented." );
            }
            else
#endif /* notdef PG_PRE74 */
            {
                OGRField  sFieldValue;

                if( OGRParseDate( PQgetvalue( hCursorResult, iRecord, iField ),
                                  &sFieldValue, 0 ) )
                {
                    poFeature->SetField( iOGRField, &sFieldValue );
                }
            }
        }
        else
        {
#if !defined(PG_PRE74)
            if ( PQfformat( hCursorResult, iField ) == 1 &&
                 eOGRType != OFTString ) // Binary data
            {
                if ( eOGRType == OFTInteger )
                {
                    int nVal;
                    memcpy( &nVal, PQgetvalue( hCursorResult, iRecord, iField ), sizeof(int) );
                    CPL_MSBPTR32(&nVal);
                    poFeature->SetField( iOGRField, nVal );
                }
                else if ( eOGRType == OFTReal )
                {
                    double dfVal;
                    memcpy( &dfVal, PQgetvalue( hCursorResult, iRecord, iField ), sizeof(double) );
                    CPL_MSBPTR64(&dfVal);
                    poFeature->SetField( iOGRField, dfVal );
                }
            }
            else
#endif /* notdef PG_PRE74 */
                poFeature->SetField( iOGRField,
                                     PQgetvalue( hCursorResult, iRecord, iField ) );
        }
    }

    return poFeature;
}

/************************************************************************/
/*                         GetNextRawFeature()                          */
/************************************************************************/

OGRFeature *OGRPGLayer::GetNextRawFeature()

{
    PGconn      *hPGConn = poDS->GetPGConn();
    CPLString   osCommand;

/* -------------------------------------------------------------------- */
/*      Do we need to establish an initial query?                       */
/* -------------------------------------------------------------------- */
    if( iNextShapeId == 0 && hCursorResult == NULL )
    {
        CPLAssert( pszQueryStatement != NULL );

        poDS->FlushSoftTransaction();
        poDS->SoftStartTransaction();

        if ( poDS->bUseBinaryCursor )
            osCommand.Printf( "DECLARE %s BINARY CURSOR for %s",
                              pszCursorName, pszQueryStatement );
        else
            osCommand.Printf( "DECLARE %s CURSOR for %s",
                              pszCursorName, pszQueryStatement );

        CPLDebug( "OGR_PG", "PQexec(%s)", osCommand.c_str() );

        hCursorResult = PQexec(hPGConn, osCommand );
        OGRPGClearResult( hCursorResult );

        osCommand.Printf( "FETCH %d in %s", CURSOR_PAGE, pszCursorName );
        hCursorResult = PQexec(hPGConn, osCommand );

        bCursorActive = TRUE;

        nResultOffset = 0;
    }

/* -------------------------------------------------------------------- */
/*      Are we in some sort of error condition?                         */
/* -------------------------------------------------------------------- */
    if( hCursorResult == NULL
        || PQresultStatus(hCursorResult) != PGRES_TUPLES_OK )
    {
        CPLDebug( "OGR_PG", "PQclear() on an error condition");

        OGRPGClearResult( hCursorResult );

        iNextShapeId = MAX(1,iNextShapeId);
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Do we need to fetch more records?                               */
/* -------------------------------------------------------------------- */
    if( nResultOffset >= PQntuples(hCursorResult)
        && bCursorActive )
    {
        OGRPGClearResult( hCursorResult );
        
        osCommand.Printf( "FETCH %d in %s", CURSOR_PAGE, pszCursorName );
        hCursorResult = PQexec(hPGConn, osCommand );

        nResultOffset = 0;
    }

/* -------------------------------------------------------------------- */
/*      Are we out of results?  If so complete the transaction, and     */
/*      cleanup, but don't reset the next shapeid.                      */
/* -------------------------------------------------------------------- */
    if( nResultOffset >= PQntuples(hCursorResult) )
    {
        OGRPGClearResult( hCursorResult );

        if( bCursorActive )
        {
            osCommand.Printf( "CLOSE %s", pszCursorName );

            hCursorResult = PQexec(hPGConn, osCommand);
            OGRPGClearResult( hCursorResult );
        }

        poDS->FlushSoftTransaction();

        hCursorResult = NULL;
        bCursorActive = FALSE;

        iNextShapeId = MAX(1,iNextShapeId);

        return NULL;
    }


/* -------------------------------------------------------------------- */
/*      Create a feature from the current result.                       */
/* -------------------------------------------------------------------- */
    OGRFeature *poFeature = RecordToFeature( nResultOffset );

    nResultOffset++;
    iNextShapeId++;

    return poFeature;
}

/************************************************************************/
/*                             GetFeature()                             */
/************************************************************************/

OGRFeature *OGRPGLayer::GetFeature( long nFeatureId )

{
    /*
     * TODO: This should be implemented!
     * See related Bug 1445
     * http://bugzilla.remotesensing.org/show_bug.cgi?id=1445
     */

    return NULL;
}

/************************************************************************/
/*                           HEXToGeometry()                            */
/************************************************************************/

OGRGeometry *OGRPGLayer::HEXToGeometry( const char *pszBytea )

{
    GByte   *pabyWKB = NULL;
    int     iSrc=0;
    int     iDst=0;
    OGRGeometry *poGeometry = NULL;
    unsigned int ewkbFlags = 0;

    if( pszBytea == NULL )
        return NULL;

/* -------------------------------------------------------------------- */
/*      Convert hex to binary.                                          */
/* -------------------------------------------------------------------- */
    pabyWKB = (GByte *) CPLMalloc(strlen(pszBytea)+1);
    while( pszBytea[iSrc] != '\0' )
    {
        if( pszBytea[iSrc] >= '0' && pszBytea[iSrc] <= '9' )
            pabyWKB[iDst] = pszBytea[iSrc] - '0';
        else if( pszBytea[iSrc] >= 'A' && pszBytea[iSrc] <= 'F' )
            pabyWKB[iDst] = pszBytea[iSrc] - 'A' + 10;
        else if( pszBytea[iSrc] >= 'a' && pszBytea[iSrc] <= 'f' )
            pabyWKB[iDst] = pszBytea[iSrc] - 'a' + 10;
        else
            pabyWKB[iDst] = 0;

        pabyWKB[iDst] *= 16;

        iSrc++;

        if( pszBytea[iSrc] >= '0' && pszBytea[iSrc] <= '9' )
            pabyWKB[iDst] += pszBytea[iSrc] - '0';
        else if( pszBytea[iSrc] >= 'A' && pszBytea[iSrc] <= 'F' )
            pabyWKB[iDst] += pszBytea[iSrc] - 'A' + 10;
        else if( pszBytea[iSrc] >= 'a' && pszBytea[iSrc] <= 'f' )
            pabyWKB[iDst] += pszBytea[iSrc] - 'a' + 10;
        else
            pabyWKB[iDst] += 0;

        iSrc++;
        iDst++;
    }

/* -------------------------------------------------------------------- */
/*      Detect XYZM variant of PostGIS EWKB                             */
/*                                                                      */
/*      OGR does not support parsing M coordinate,                      */
/*      so we return NULL geometry.                                     */
/* -------------------------------------------------------------------- */
    memcpy(&ewkbFlags, pabyWKB+1, 4);
    OGRwkbByteOrder eByteOrder = (pabyWKB[0] == 0 ? wkbXDR : wkbNDR);
    if( OGR_SWAP( eByteOrder ) )
        ewkbFlags= CPL_SWAP32(ewkbFlags);

    if (ewkbFlags & 0x40000000)
    {
        CPLError( CE_Failure, CPLE_AppDefined,
            "Reading EWKB with 4-dimensional coordinates (XYZM) is not supported" );

        CPLFree( pabyWKB );
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      PostGIS EWKB format includes an  SRID, but this won't be        */
/*      understood by OGR, so if the SRID flag is set, we remove the    */
/*      SRID (bytes at offset 5 to 8).                                  */
/* -------------------------------------------------------------------- */
    if( (pabyWKB[0] == 0 /* big endian */ && (pabyWKB[1] & 0x20) )
        || (pabyWKB[0] != 0 /* little endian */ && (pabyWKB[4] & 0x20)) )