ogrfmedatasource.cpp

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        return NULL;
    }
    
/* -------------------------------------------------------------------- */
/*      Apply extra values to user directives.                          */
/* -------------------------------------------------------------------- */
    int            i;

    for( i = 2; papszLines[i] != NULL; i++ )
        poUserDirectives->append( papszLines[i] );

/* -------------------------------------------------------------------- */
/*      Prepare reader:dataset response string.                         */
/* -------------------------------------------------------------------- */
    char     *pszReturn;

    pszReturn = CPLStrdup(CPLSPrintf("%s:%s", papszLines[0], papszLines[1] ));

    CSLDestroy( papszLines );

    return pszReturn;
}

/************************************************************************/
/*                         SaveDefinitionFile()                         */
/************************************************************************/

static void SaveDefinitionFile( const char *pszFilename, 
                                const char *pszReader, 
                                const char *pszDatasource,
                                IFMEStringArray &oUserDirectives )

{
    FILE     *fp;
    int      i;

    fp = VSIFOpen( CPLResetExtension( pszFilename, "fdd" ), "wt" );
    if( fp == NULL )
        return;

    fprintf( fp, "%s\n", pszReader );
    fprintf( fp, "%s\n", pszDatasource );

    for( i = 0; i < (int) oUserDirectives.entries(); i++ )
    {
        fprintf( fp, "%s\n", oUserDirectives(i) );
    }

    VSIFClose( fp );
}

/************************************************************************/
/*                             ExtractSRS()                             */
/************************************************************************/

OGRSpatialReference *
OGRFMEDataSource::ExtractSRS()

{
/* -------------------------------------------------------------------- */
/*      Try to find the COORDSYS in the user directives.                */
/* -------------------------------------------------------------------- */
    const char *pszCoordSys = NULL;
    for( int i = 0; i < (int) poUserDirectives->entries(); i += 2 )
    {
        if( EQUAL((*poUserDirectives)(i),"COORDSYS") )
            pszCoordSys = (*poUserDirectives)(i+1);
    }

    if( pszCoordSys == NULL || strlen(pszCoordSys) == 0 )
        return NULL;

/* -------------------------------------------------------------------- */
/*      Translate FME name to an OGRSpatialReference.                   */
/* -------------------------------------------------------------------- */
    return FME2OGRSpatialRef( pszCoordSys );
}

/************************************************************************/
/*                                Open()                                */
/************************************************************************/

int OGRFMEDataSource::Open( const char * pszCompositeName )

{
    FME_MsgNum          err;

    CPLAssert( poSession == NULL );  // only open once

/* -------------------------------------------------------------------- */
/*      Do some initial validation.  Does this even look like it        */
/*      could plausibly be an FME suitable name?  We accept PROMPT:,    */
/*      <reader>: or anything ending in .fdd as a reasonable candidate. */
/* -------------------------------------------------------------------- */
    int  i;

    for( i = 0; pszCompositeName[i] != ':' && pszCompositeName[i] != '\0'; i++)
    {
        if( pszCompositeName[i] == '/' || pszCompositeName[i] == '\\'
            || pszCompositeName[i] == '.' )
            break;
    }
         
    if( (i < 2 || pszCompositeName[i] != ':' 
         || EQUALN(pszCompositeName,"OCI:",4)
         || EQUALN(pszCompositeName,"gltp:",5)
         || EQUALN(pszCompositeName,"http",4)
         || EQUALN(pszCompositeName,"DODS:",5)
         || EQUALN(pszCompositeName,"ODBC:",5)
         || EQUALN(pszCompositeName,"MYSQL:",5))
        && !EQUAL(CPLGetExtension( pszCompositeName ), "fdd")
        && !EQUALN(pszCompositeName,"PROMPT",6) )
    {
        CPLDebug( kPROVIDERNAME, 
                  "OGRFMEDataSource::Open(%s) don't try to open via FME.", 
                  pszCompositeName );
        return FALSE;
    }

    CPLDebug( kPROVIDERNAME, "OGRFMEDataSource::Open(%s):%p/%d", 
              pszCompositeName, this, CPLGetPID() );

/* -------------------------------------------------------------------- */
/*      Create an FME Session.                                          */
/* -------------------------------------------------------------------- */
    poSession = AcquireSession();
    if( poSession == NULL )
        return FALSE;

    nSharedSessionRefCount++;

    CPLDebug( kPROVIDERNAME, "%p:acquired session", this );

    poUserDirectives = poSession->createStringArray();

/* -------------------------------------------------------------------- */
/*      Redirect FME log messages through CPLDebug().                   */
/* -------------------------------------------------------------------- */
    IFMELogFile   *poLogFile = poSession->logFile();

    poLogFile->setFileName( NULL, FME_FALSE );
    poLogFile->setCallBack( FME_Logger );

    CPLDebug( kPROVIDERNAME, "%p:reset logfile", this );

/* -------------------------------------------------------------------- */
/*      Prompt for a source, if none is provided.                       */
/* -------------------------------------------------------------------- */
    if( EQUAL(pszCompositeName,"") || EQUALN(pszCompositeName,"PROMPT",6) )
    {
        pszName = PromptForSource();
        if( pszName == NULL )
        {
            ReleaseSession();
            return FALSE;
        }
    }
    else if( CPLGetExtension( pszCompositeName ) != NULL
             && EQUAL(CPLGetExtension( pszCompositeName ),"fdd") )
    {
        pszName = ReadFileSource(pszCompositeName);
        if( pszName == NULL )
        {
            ReleaseSession();
            return FALSE;
        }
    }
    else
    {
        pszName = CPLStrdup( pszCompositeName );
    }

/* -------------------------------------------------------------------- */
/*      Extract the reader name and password compontents.  The          */
/*      reader name will be followed by a single colon and then the     */
/*      FME DATASET name.                                               */
/* -------------------------------------------------------------------- */
    for( i = 0; pszName[i] != '\0' && pszName[i] != ':'; i++ ) {}

    if( pszName[i] == '\0' || i < 2 )
    {
        CPLError( CE_Failure, CPLE_AppDefined, 
                  "Failed to parse reader and data source from:\n%s", 
                  pszName );
        ReleaseSession();
        return FALSE;
    }

    pszReaderName = CPLStrdup( pszName );
    pszReaderName[i] = '\0';

    pszDataset = CPLStrdup(pszName + i + 1);

    CPLDebug( kPROVIDERNAME, "%s:parsed out dataset", pszDataset );

/* -------------------------------------------------------------------- */
/*      If we prompted for a defintion that includes a file to save     */
/*      it to, do the save now.                                         */
/* -------------------------------------------------------------------- */
    if( EQUALN(pszCompositeName,"PROMPT:",7) 
        && strlen(pszCompositeName) > 7 )
    {
        SaveDefinitionFile( pszCompositeName+7, 
                            pszReaderName, pszDataset, 
                            *poUserDirectives );
    }

/* -------------------------------------------------------------------- */
/*      Is there a Coordsys statement in the user directives?           */
/* -------------------------------------------------------------------- */
    OGRSpatialReference *poSRS = ExtractSRS();

    CPLDebug( kPROVIDERNAME, "got the SRS parsed");

    bCoordSysOverride = poSRS != NULL;

/* -------------------------------------------------------------------- */
/*      Allocate an FME string, and feature for use here and            */
/*      elsewhere.                                                      */
/* -------------------------------------------------------------------- */
    poFMEFeature = poSession->createFeature();
    poFMEString = poSession->createString();

/* -------------------------------------------------------------------- */
/*      Are we going to use the direct access DB mechanism, or the      */
/*      spatiallly cached (dumb reader) mechanism.                      */
/* -------------------------------------------------------------------- */
    bUseCaching = !EQUALN(pszReaderName,"SDE",3) 
               && !EQUALN(pszReaderName,"ORACLE",6);

/* -------------------------------------------------------------------- */
/*      Is there already a cache for this dataset?  If so, we will      */
/*      use it.                                                         */
/* -------------------------------------------------------------------- */
#ifdef SUPPORT_PERSISTENT_CACHE
    OGRFMECacheIndex   oCacheIndex( 
                           CPLFormFilename(GetTmpDir(), "ogrfmeds", "ind" ) );
    CPLXMLNode        *psMatchDS = NULL;

    if( bUseCaching && oCacheIndex.Lock() && oCacheIndex.Load() )
    {
        int bNeedSave = oCacheIndex.ExpireOldCaches( poSession );

        psMatchDS = oCacheIndex.FindMatch( pszReaderName, pszDataset, 
                                           *poUserDirectives );

        if( psMatchDS != NULL )
        {
            oCacheIndex.Reference( psMatchDS );
            oCacheIndex.Save();

            psMatchDS = CPLCloneXMLTree( psMatchDS );
            oCacheIndex.Unlock();

        }
        else
        {
            if( bNeedSave )
                oCacheIndex.Save();

            oCacheIndex.Unlock();
        }

        if( psMatchDS != NULL )
        {
            if( InitializeFromXML( psMatchDS ) )
            {
                CPLDestroyXMLNode( psMatchDS );
                ReleaseSession();

                return TRUE;
            }

            CPLDestroyXMLNode( psMatchDS );
        }
    }
#endif /* def SUPPORT_PERSISTENT_CACHE */

/* -------------------------------------------------------------------- */
/*      Create a reader.                                                */
/* -------------------------------------------------------------------- */
    IFMEStringArray     *poParms = poSession->createStringArray();

    for( i = 0; i < (int) poUserDirectives->entries(); i++ )
        CPLDebug( kPROVIDERNAME, "oUserDirectives(%d) = '%s'", 
                  i, (*poUserDirectives)(i) );

    poReader = poSession->createReader(pszReaderName, FME_FALSE, 
                                       poUserDirectives);
    if( poReader == NULL )
    {
        CPLFMEError( poSession,
                     "Failed to create reader of type `%s'.\n",
                     pszReaderName );
        ReleaseSession();
        return FALSE;
    }

    CPLDebug( kPROVIDERNAME, "%p:reader created.", this );

/* -------------------------------------------------------------------- */
/*      Now try to open the dataset.                                    */
/* -------------------------------------------------------------------- */
    err = poReader->open( pszDataset, *poParms );
    if( err )
    {
        CPLFMEError( poSession,
                     "Failed to open dataset `%s' with reader of type `%s'.\n",
                     pszDataset, pszReaderName );
        ReleaseSession();
        return FALSE;
    }

    CPLDebug( kPROVIDERNAME, "%p:reader opened.", this );

/* -------------------------------------------------------------------- */
/*      There are some circumstances where we want to keep a            */
/*      "connection" open for a data source.  Offer this reader for     */
/*      connection caching.                                             */
/* -------------------------------------------------------------------- */
    OfferForConnectionCaching( poReader, pszReaderName, 
                               pszDataset );

/* -------------------------------------------------------------------- */
/*      Create a layer for each schema feature.                         */
/* -------------------------------------------------------------------- */
    FME_Boolean         eEndOfSchema;

    while( TRUE )
    {
        err = poReader->readSchema( *poFMEFeature, eEndOfSchema );
        if( err )
        {
            CPLFMEError( poSession, "IFMEReader::readSchema() failed." );
            ReleaseSession();
            return FALSE;
        }

        if( eEndOfSchema == FME_TRUE )
            break;

        CPLDebug( kPROVIDERNAME, "%p:readSchema() got %s.", 
                  this, poFMEFeature->getFeatureType() );