C++ CPLReadLine2L函数代码示例

const char* E00GRIDDataset::ReadLine()
{
    if (e00ReadPtr)
        return E00ReadNextLine(e00ReadPtr);

    return CPLReadLine2L(fp, 81, NULL);
}

int OGRHTFSoundingLayer::GetFeatureCount(int bForce)
{
    if (m_poFilterGeom != NULL || m_poAttrQuery != NULL)
        return OGRHTFLayer::GetFeatureCount(bForce);

    if (nTotalSoundings != 0)
        return nTotalSoundings;

    ResetReading();
    if (fpHTF == NULL)
        return 0;

    int nCount = 0;
    const char* pszLine;
    while( (pszLine = CPLReadLine2L(fpHTF, 1024, NULL)) != NULL)
    {
        if (pszLine[0] == ';')
        {
            /* comment */ ;
        }
        else if (pszLine[0] == 0)
            break;
        else if (strcmp(pszLine, "END OF SOUNDING DATA") == 0)
            break;
        else
            nCount ++;
    }

    ResetReading();
    return nCount;
}

OGRFeature *OGROpenAirLabelLayer::GetNextRawFeature()
{
    const char* pszLine;
    double dfLat = 0, dfLon = 0;
    int bHasCoord = FALSE;

    while(TRUE)
    {
        pszLine = CPLReadLine2L(fpOpenAir, 1024, NULL);
        if (pszLine == NULL)
            return NULL;

        if (pszLine[0] == '*' || pszLine[0] == '\0')
            continue;

        if (EQUALN(pszLine, "AC ", 3))
        {
            if (osCLASS.size() != 0)
            {
                osNAME = "";
                osCEILING = "";
                osFLOOR = "";
            }
            osCLASS = pszLine + 3;
        }
        else if (EQUALN(pszLine, "AN ", 3))
            osNAME = pszLine + 3;
        else if (EQUALN(pszLine, "AH ", 3))
            osCEILING = pszLine + 3;
        else if (EQUALN(pszLine, "AL ", 3))
            osFLOOR = pszLine + 3;
        else if (EQUALN(pszLine, "AT ", 3))
        {
            bHasCoord = OGROpenAirGetLatLon(pszLine + 3, dfLat, dfLon);
            break;
        }
    }

    OGRFeature* poFeature = new OGRFeature(poFeatureDefn);
    poFeature->SetField(0, osCLASS.c_str());
    poFeature->SetField(1, osNAME.c_str());
    poFeature->SetField(2, osFLOOR.c_str());
    poFeature->SetField(3, osCEILING.c_str());

    CPLString osStyle;
    osStyle.Printf("LABEL(t:\"%s\")", osNAME.c_str());
    poFeature->SetStyleString(osStyle.c_str());

    if (bHasCoord)
    {
        OGRPoint* poPoint = new OGRPoint(dfLon, dfLat);
        poPoint->assignSpatialReference(poSRS);
        poFeature->SetGeometryDirectly(poPoint);
    }

    poFeature->SetFID(nNextFID++);

    return poFeature;
}

void OGRHTFSoundingLayer::ResetReading()

{
    OGRHTFLayer::ResetReading();
    if (fpHTF)
    {
        const char* pszLine;
        while( (pszLine = CPLReadLine2L(fpHTF, 1024, NULL)) != NULL)
        {
            if (strcmp(pszLine, "SOUNDING DATA") == 0)
            {
                if (bHasFPK)
                    pszLine = CPLReadLine2L(fpHTF, 1024, NULL);
                break;
            }
        }
        if (pszLine == NULL)
            bEOF = TRUE;
    }
}

OGRFeature *OGRAeronavFAANAVAIDLayer::GetNextRawFeature()
{
    char szBuffer[134];

    while( true )
    {
        const char* pszLine = CPLReadLine2L(fpAeronavFAA, 134, nullptr);
        if (pszLine == nullptr)
        {
            bEOF = true;
            return nullptr;
        }
        if (strlen(pszLine) != 132)
            continue;
        if ( !(pszLine[psRecordDesc->nLatStartCol-1] == 'N' ||
               pszLine[psRecordDesc->nLatStartCol-1] == 'S') )
            continue;
        if ( !(pszLine[psRecordDesc->nLonStartCol-1] == 'E' ||
               pszLine[psRecordDesc->nLonStartCol-1] == 'W') )
            continue;

        OGRFeature* poFeature = new OGRFeature(poFeatureDefn);
        poFeature->SetFID(nNextFID ++);

        for( int i=0; i < psRecordDesc->nFields; i++ )
        {
            int nWidth = psRecordDesc->pasFields[i].nLastCol - psRecordDesc->pasFields[i].nStartCol + 1;
            strncpy(szBuffer, pszLine + psRecordDesc->pasFields[i].nStartCol - 1, nWidth);
            szBuffer[nWidth] = 0;
            while(nWidth > 0 && szBuffer[nWidth - 1] == ' ')
            {
                szBuffer[nWidth - 1] = 0;
                nWidth --;
            }
            if (nWidth != 0)
                poFeature->SetField(i, szBuffer);
        }

        double dfLat = 0.0;
        double dfLon = 0.0;
        GetLatLon(pszLine + psRecordDesc->nLatStartCol - 1,
                  pszLine + psRecordDesc->nLonStartCol - 1,
                  dfLat,
                  dfLon);

        OGRGeometry* poGeom = new OGRPoint(dfLon, dfLat);
        poGeom->assignSpatialReference(poSRS);
        poFeature->SetGeometryDirectly( poGeom );
        return poFeature;
    }
}

void OGRSEGP1Layer::ResetReading()

{
    nNextFID = 0;
    bEOF = FALSE;
    VSIFSeekL( fp, 0, SEEK_SET );

    /* Skip first 20 header lines */
    const char* pszLine = NULL;
    for(int i=0; i<20;i++)
    {
        pszLine = CPLReadLine2L(fp,81,NULL);
        if (pszLine == NULL)
        {
            bEOF = TRUE;
            break;
        }
    }
}

void OGRSEGP1Layer::ResetReading()

{
    nNextFID = 0;
    bEOF = false;
    VSIFSeekL( fp, 0, SEEK_SET );

    /* Skip first 20 header lines */
    const char* pszLine = nullptr;
    for(int i=0; i<20;i++)
    {
        pszLine = CPLReadLine2L(fp,81,nullptr);
        if (pszLine == nullptr)
        {
            bEOF = true;
            break;
        }
    }
}

GDALDataset *E00GRIDDataset::Open( GDALOpenInfo * poOpenInfo )

{
    if (!Identify(poOpenInfo))
        return NULL;

/* -------------------------------------------------------------------- */
/*      Find dataset characteristics                                    */
/* -------------------------------------------------------------------- */
    VSILFILE* fp = VSIFOpenL(poOpenInfo->pszFilename, "rb");
    if (fp == NULL)
        return NULL;

    if (poOpenInfo->eAccess == GA_Update)
    {
        CPLError( CE_Failure, CPLE_NotSupported,
                  "The E00GRID driver does not support update access to existing"
                  " datasets.\n" );
        VSIFCloseL(fp);
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Create a corresponding GDALDataset.                             */
/* -------------------------------------------------------------------- */
    E00GRIDDataset *poDS = new E00GRIDDataset();
    if (strstr((const char*)poOpenInfo->pabyHeader, "\r\n") != NULL)
        poDS->nBytesEOL = 2;
    poDS->fp = fp;

    /* read EXP  0 or EXP  1 line */
    const char* pszLine = CPLReadLine2L(fp, 81, NULL);
    if (pszLine == NULL)
    {
        CPLDebug("E00GRID", "Bad 1st line");
        delete poDS;
        return NULL;
    }
    bool bCompressed = STARTS_WITH_CI(pszLine, "EXP  1");

    E00ReadPtr e00ReadPtr = NULL;
    if (bCompressed)
    {
        VSIRewindL(fp);
        e00ReadPtr = E00ReadCallbackOpen(poDS,
                                         E00GRIDDataset::ReadNextLine,
                                         E00GRIDDataset::Rewind);
        if (e00ReadPtr == NULL)
        {
            delete poDS;
            return NULL;
        }
        E00ReadNextLine(e00ReadPtr);
        poDS->e00ReadPtr = e00ReadPtr;
    }

    /* skip GRD  2 line */
    if (e00ReadPtr)
        pszLine = E00ReadNextLine(e00ReadPtr);
    else
        pszLine = CPLReadLine2L(fp, 81, NULL);
    if (pszLine == NULL || !STARTS_WITH_CI(pszLine, "GRD  2"))
    {
        CPLDebug("E00GRID", "Bad 2nd line");
        delete poDS;
        return NULL;
    }

    /* read ncols, nrows and nodata value */
    if (e00ReadPtr)
        pszLine = E00ReadNextLine(e00ReadPtr);
    else
        pszLine = CPLReadLine2L(fp, 81, NULL);
    if (pszLine == NULL || strlen(pszLine) <
                E00_INT_SIZE+E00_INT_SIZE+2+E00_DOUBLE_SIZE)
    {
        CPLDebug("E00GRID", "Bad 3rd line");
        delete poDS;
        return NULL;
    }

    const int nRasterXSize = atoi(pszLine);
    const int nRasterYSize = atoi(pszLine + E00_INT_SIZE);

    if (!GDALCheckDatasetDimensions(nRasterXSize, nRasterYSize))
    {
        delete poDS;
        return NULL;
    }

    GDALDataType eDT = GDT_Float32;

    if (STARTS_WITH_CI(pszLine + E00_INT_SIZE + E00_INT_SIZE, " 1"))
        eDT = GDT_Int32;
    else if (STARTS_WITH_CI(pszLine + E00_INT_SIZE + E00_INT_SIZE, " 2"))
        eDT = GDT_Float32;
    else
    {
        CPLDebug("E00GRID", "Unknown data type : %s", pszLine);
    }
//.........这里部分代码省略.........

const char* E00GRIDDataset::ReadNextLine(void * ptr)
{
    E00GRIDDataset* poDS = (E00GRIDDataset*) ptr;
    poDS->nPosBeforeReadLine = VSIFTellL(poDS->fp);
    return CPLReadLine2L(poDS->fp, 256, NULL);
}

OGRFeature *OGRSEGP1Layer::GetNextRawFeature()
{
    if( bEOF )
        return nullptr;

    const char* pszLine = nullptr;
    while( true )
    {
        pszLine = CPLReadLine2L(fp,81,nullptr);
        if (pszLine == nullptr || STARTS_WITH_CI(pszLine, "EOF"))
        {
            bEOF = true;
            return nullptr;
        }

        int nLineLen = static_cast<int>(strlen(pszLine));
        while(nLineLen > 0 && pszLine[nLineLen-1] == ' ')
        {
            ((char*)pszLine)[nLineLen-1] = '\0';
            nLineLen --;
        }

        char* pszExpandedLine = ExpandTabs(pszLine);
        pszLine = pszExpandedLine;
        nLineLen = static_cast<int>(strlen(pszLine));

        OGRFeature* poFeature = new OGRFeature(poFeatureDefn);
        poFeature->SetFID(nNextFID ++);

        OGRGeometry* poGeom = nullptr;

        if (nLatitudeCol-1 + 19 <= nLineLen)
        {
            char szDeg[3+1];
            char szMin[2+1];
            char szSec[4+1];

            ExtractField(szDeg, pszLine, nLatitudeCol-1, 2);
            ExtractField(szMin, pszLine, nLatitudeCol+2-1, 2);
            ExtractField(szSec, pszLine, nLatitudeCol+2+2-1, 4);
            double dfLat = atoi(szDeg) + atoi(szMin) / 60.0 + atoi(szSec) / 100.0 / 3600.0;
            if (pszLine[nLatitudeCol+2+2+4-1] == 'S')
                dfLat = -dfLat;
            poFeature->SetField(SEGP1_FIELD_LATITUDE, dfLat);

            ExtractField(szDeg, pszLine, nLatitudeCol+9-1, 3);
            ExtractField(szMin, pszLine, nLatitudeCol+9+3-1, 2);
            ExtractField(szSec, pszLine, nLatitudeCol+9+3+2-1, 4);
            double dfLon = atoi(szDeg) + atoi(szMin) / 60.0 + atoi(szSec) / 100.0 / 3600.0;
            if (pszLine[nLatitudeCol+9+3+2+4-1] == 'W')
                dfLon = -dfLon;
            poFeature->SetField(SEGP1_FIELD_LONGITUDE, dfLon);

            if (!bUseEastingNorthingAsGeometry)
                poGeom = new OGRPoint(dfLon, dfLat);
        }

        /* Normal layout -> extract other fields */
        if (nLatitudeCol == 27 && nLineLen >= 26-1+1)
        {
            char szLineName[16 + 1];
            ExtractField(szLineName, pszLine, 2-1, 16);
            int i = 15;
            while (i >= 0)
            {
                if (szLineName[i] == ' ')
                    szLineName[i] = '\0';
                else
                    break;
                i --;
            }
            poFeature->SetField(SEGP1_FIELD_LINENAME, szLineName);

            char szPointNumber[8+1];
            ExtractField(szPointNumber, pszLine, 18-1, 8);
            poFeature->SetField(SEGP1_FIELD_POINTNUMBER, atoi(szPointNumber));

            char szReshootCode[1+1];
            ExtractField(szReshootCode, pszLine, 26-1, 1);
            poFeature->SetField(SEGP1_FIELD_RESHOOTCODE, szReshootCode);

            if (nLineLen >= 61)
            {
                char szEasting[8+1];
                ExtractField(szEasting, pszLine, 46-1, 8);
                double dfEasting = CPLAtof(szEasting);
                poFeature->SetField(SEGP1_FIELD_EASTING, dfEasting);

                char szNorthing[8+1];
                ExtractField(szNorthing, pszLine, 54-1, 8);
                double dfNorthing = CPLAtof(szNorthing);
                poFeature->SetField(SEGP1_FIELD_NORTHING, dfNorthing);

                if (bUseEastingNorthingAsGeometry)
                    poGeom = new OGRPoint(dfEasting, dfNorthing);
            }

            if (nLineLen >= 66)
            {
                char szDepth[5+1];
//.........这里部分代码省略.........

OGRHTFSoundingLayer::OGRHTFSoundingLayer( const char* pszFilename, int nZone, int bIsNorth, int nTotalSoundings ) :
                                        OGRHTFLayer(pszFilename, nZone, bIsNorth)

{
    poFeatureDefn = new OGRFeatureDefn( "sounding" );
    poFeatureDefn->Reference();
    poFeatureDefn->SetGeomType( wkbPoint  );

    this->nTotalSoundings = nTotalSoundings;
    bHasFPK = FALSE;
    nFieldsPresent = 0;
    panFieldPresence = NULL;
    nEastingIndex = -1;
    nNorthingIndex = -1;

    const char* pszLine;
    int bSoundingHeader = FALSE;
    while( fpHTF != NULL &&
           (pszLine = CPLReadLine2L(fpHTF, 1024, NULL)) != NULL)
    {
        if (strncmp(pszLine, "SOUNDING HEADER", strlen("SOUNDING HEADER")) == 0)
            bSoundingHeader = TRUE;
        else if (bSoundingHeader && strlen(pszLine) > 10 &&
                 pszLine[0] == '[' && pszLine[3] == ']' &&
                 pszLine[4] == ' ' &&
                 strstr(pszLine + 5, " =") != NULL)
        {
            char* pszName = CPLStrdup(pszLine + 5);
            *strstr(pszName, " =") = 0;
            char* pszPtr = pszName;
            for(;*pszPtr;pszPtr++)
            {
                if (*pszPtr == ' ')
                    *pszPtr = '_';
            }
            OGRFieldType eType;
            if (strcmp(pszName, "REJECTED_SOUNDING") == 0 ||
                strcmp(pszName, "FIX_NUMBER") == 0 ||
                strcmp(pszName, "NBA_FLAG") == 0 ||
                strcmp(pszName, "SOUND_VELOCITY") == 0 ||
                strcmp(pszName, "PLOTTED_SOUNDING") == 0)
                eType = OFTInteger;
            else if (strcmp(pszName, "LATITUDE") == 0 ||
                     strcmp(pszName, "LONGITUDE") == 0 ||
                     strcmp(pszName, "EASTING") == 0 ||
                     strcmp(pszName, "NORTHING") == 0 ||
                     strcmp(pszName, "DEPTH") == 0 ||
                     strcmp(pszName, "TPE_POSITION") == 0 ||
                     strcmp(pszName, "TPE_DEPTH") == 0 ||
                     strcmp(pszName, "TIDE") == 0 ||
                     strcmp(pszName, "DEEP_WATER_CORRECTION") == 0 ||
                     strcmp(pszName, "VERTICAL_BIAS_CORRECTION") == 0)
                eType = OFTReal;
            else
                eType = OFTString;
            OGRFieldDefn    oField( pszName, eType);
            poFeatureDefn->AddFieldDefn( &oField);
            CPLFree(pszName);
        }
        else if (strcmp(pszLine, "END OF SOUNDING HEADER") == 0)
        {
            bSoundingHeader = FALSE;
        }
        else if (strcmp(pszLine, "SOUNDING DATA") == 0)
        {
            pszLine = CPLReadLine2L(fpHTF, 1024, NULL);
            if (pszLine == NULL)
                break;
            if (pszLine[0] == '[' &&
                (int)strlen(pszLine) == 2 + poFeatureDefn->GetFieldCount())
            {
                bHasFPK = TRUE;
                panFieldPresence = (int*)CPLMalloc(sizeof(int) *
                                            poFeatureDefn->GetFieldCount());
                int i;
                for(i=0;i<poFeatureDefn->GetFieldCount();i++)
                {
                    panFieldPresence[i] = pszLine[1 + i] != '0';
                    nFieldsPresent += panFieldPresence[i];
                }
            }
            break;
        }
    }

    if (!bHasFPK)
    {
        panFieldPresence = (int*)CPLMalloc(sizeof(int) *
                                           poFeatureDefn->GetFieldCount());
        int i;
        for(i=0;i<poFeatureDefn->GetFieldCount();i++)
            panFieldPresence[i] = TRUE;
        nFieldsPresent = poFeatureDefn->GetFieldCount();
    }

    int nIndex;
    nIndex = poFeatureDefn->GetFieldIndex("EASTING");
    if (nIndex < 0 || !panFieldPresence[nIndex])
    {
        CPLError(CE_Failure, CPLE_NotSupported, "Cannot find EASTING field");
//.........这里部分代码省略.........

CPLErr XYZRasterBand::IReadBlock( int nBlockXOff, int nBlockYOff,
                                  void * pImage )

{
    XYZDataset *poGDS = (XYZDataset *) poDS;
    
    if (poGDS->fp == NULL)
        return CE_Failure;

    int nLineInFile = nBlockYOff * nBlockXSize;
    if (poGDS->nDataLineNum > nLineInFile)
    {
        poGDS->nDataLineNum = 0;
        VSIFSeekL(poGDS->fp, 0, SEEK_SET);

        for(int i=0;i<poGDS->nCommentLineCount;i++)
            CPLReadLine2L(poGDS->fp, 100, NULL);

        if (poGDS->bHasHeaderLine)
        {
            const char* pszLine = CPLReadLine2L(poGDS->fp, 100, 0);
            if (pszLine == NULL)
            {
                memset(pImage, 0, nBlockXSize * (GDALGetDataTypeSize(eDataType) / 8));
                return CE_Failure;
            }
            poGDS->nLineNum ++;
        }
    }

    while(poGDS->nDataLineNum < nLineInFile)
    {
        const char* pszLine = CPLReadLine2L(poGDS->fp, 100, 0);
        if (pszLine == NULL)
        {
            memset(pImage, 0, nBlockXSize * (GDALGetDataTypeSize(eDataType) / 8));
            return CE_Failure;
        }
        poGDS->nLineNum ++;

        const char* pszPtr = pszLine;
        char ch;
        int nCol = 0;
        int bLastWasSep = TRUE;
        while((ch = *pszPtr) != '\0')
        {
            if (ch == ' ' || ch == ',' || ch == '\t' || ch == ';')
            {
                if (!bLastWasSep)
                    nCol ++;
                bLastWasSep = TRUE;
            }
            else
            {
                bLastWasSep = FALSE;
            }
            pszPtr ++;
        }

        /* Skip empty line */
        if (nCol == 0 && bLastWasSep)
            continue;

        poGDS->nDataLineNum ++;
    }

    int i;
    for(i=0;i<nBlockXSize;i++)
    {
        int nCol;
        int bLastWasSep;
        do
        {
            const char* pszLine = CPLReadLine2L(poGDS->fp, 100, 0);
            if (pszLine == NULL)
            {
                memset(pImage, 0, nBlockXSize * (GDALGetDataTypeSize(eDataType) / 8));
                return CE_Failure;
            }
            poGDS->nLineNum ++;

            const char* pszPtr = pszLine;
            char ch;
            nCol = 0;
            bLastWasSep = TRUE;
            while((ch = *pszPtr) != '\0')
            {
                if (ch == ' ' || ch == ',' || ch == '\t' || ch == ';')
                {
                    if (!bLastWasSep)
                        nCol ++;
                    bLastWasSep = TRUE;
                }
                else
                {
                    if (bLastWasSep && nCol == poGDS->nZIndex)
                    {
                        double dfZ = CPLAtofM(pszPtr);
                        if (eDataType == GDT_Float32)
                        {
//.........这里部分代码省略.........

void OGRUKOOAP190Layer::ParseHeaders()
{
    while(TRUE)
    {
        const char* pszLine = CPLReadLine2L(fp,81,NULL);
        if (pszLine == NULL || EQUALN(pszLine, "EOF", 3))
        {
            break;
        }

        int nLineLen = strlen(pszLine);
        while(nLineLen > 0 && pszLine[nLineLen-1] == ' ')
        {
            ((char*)pszLine)[nLineLen-1] = '\0';
            nLineLen --;
        }

        if (pszLine[0] != 'H')
            break;

        if (nLineLen < 33)
            continue;

        if (!bUseEastingNorthingAsGeometry &&
            strncmp(pszLine, "H1500", 5) == 0 && poSRS == NULL)
        {
            if (strncmp(pszLine + 33 - 1, "WGS84", 5) == 0 ||
                strncmp(pszLine + 33 - 1, "WGS-84", 6) == 0)
            {
                poSRS = new OGRSpatialReference(SRS_WKT_WGS84);
            }
            else if (strncmp(pszLine + 33 - 1, "WGS72", 5) == 0)
            {
                poSRS = new OGRSpatialReference();
                poSRS->SetFromUserInput("WGS72");
            }
        }
        else if (!bUseEastingNorthingAsGeometry &&
                 strncmp(pszLine, "H1501", 5) == 0 && poSRS != NULL &&
                 nLineLen >= 32 + 6 * 6 + 10)
        {
            char aszParams[6][6+1];
            char szZ[10+1];
            int i;
            for(i=0;i<6;i++)
            {
                ExtractField(aszParams[i], pszLine, 33 - 1 + i * 6, 6);
            }
            ExtractField(szZ, pszLine, 33 - 1 + 6 * 6, 10);
            poSRS->SetTOWGS84(CPLAtof(aszParams[0]),
                              CPLAtof(aszParams[1]),
                              CPLAtof(aszParams[2]),
                              CPLAtof(aszParams[3]),
                              CPLAtof(aszParams[4]),
                              CPLAtof(aszParams[5]),
                              CPLAtof(szZ));
        }
        else if (strncmp(pszLine, "H0200", 5) == 0)
        {
            char** papszTokens = CSLTokenizeString(pszLine + 33 - 1);
            for(int i = 0; papszTokens[i] != NULL; i++)
            {
                if (strlen(papszTokens[i]) == 4)
                {
                    int nVal = atoi(papszTokens[i]);
                    if (nVal >= 1900)
                    {
                        if (nYear != 0 && nYear != nVal)
                        {
                            CPLDebug("SEGUKOOA",
                                     "Several years found in H0200. Ignoring them!");
                            nYear = 0;
                            break;
                        }
                        nYear = nVal;
                    }
                }
            }
            CSLDestroy(papszTokens);
        }
    }
    VSIFSeekL( fp, 0, SEEK_SET );
}

OGRFeature *OGRARCGENLayer::GetNextRawFeature()
{
    if (bEOF)
        return NULL;

    const char* pszLine;
    OGRwkbGeometryType eType = poFeatureDefn->GetGeomType();

    if (wkbFlatten(eType) == wkbPoint)
    {
        while(TRUE)
        {
            pszLine = CPLReadLine2L(fp,256,NULL);
            if (pszLine == NULL || EQUAL(pszLine, "END"))
            {
                bEOF = TRUE;
                return NULL;
            }
            char** papszTokens = CSLTokenizeString2( pszLine, " ,", 0 );
            int nTokens = CSLCount(papszTokens);
            if (nTokens == 3 || nTokens == 4)
            {
                OGRFeature* poFeature = new OGRFeature(poFeatureDefn);
                poFeature->SetFID(nNextFID ++);
                poFeature->SetField(0, papszTokens[0]);
                if (nTokens == 3)
                    poFeature->SetGeometryDirectly(
                        new OGRPoint(CPLAtof(papszTokens[1]),
                                     CPLAtof(papszTokens[2])));
                else
                    poFeature->SetGeometryDirectly(
                        new OGRPoint(CPLAtof(papszTokens[1]),
                                     CPLAtof(papszTokens[2]),
                                     CPLAtof(papszTokens[3])));
                CSLDestroy(papszTokens);
                return poFeature;
            }
            else
                CSLDestroy(papszTokens);
        }
    }

    CPLString osID;
    OGRLinearRing* poLR =
        (wkbFlatten(eType) == wkbPolygon) ? new OGRLinearRing() : NULL;
    OGRLineString* poLS =
        (wkbFlatten(eType) == wkbLineString) ? new OGRLineString() : poLR;
    while(TRUE)
    {
        pszLine = CPLReadLine2L(fp,256,NULL);
        if (pszLine == NULL)
            break;

        if (EQUAL(pszLine, "END"))
        {
            if (osID.size() == 0)
                break;

            OGRFeature* poFeature = new OGRFeature(poFeatureDefn);
            poFeature->SetFID(nNextFID ++);
            poFeature->SetField(0, osID.c_str());
            if (wkbFlatten(eType) == wkbPolygon)
            {
                OGRPolygon* poPoly = new OGRPolygon();
                poPoly->addRingDirectly(poLR);
                poFeature->SetGeometryDirectly(poPoly);
            }
            else
                poFeature->SetGeometryDirectly(poLS);
            return poFeature;
        }

        char** papszTokens = CSLTokenizeString2( pszLine, " ,", 0 );
        int nTokens = CSLCount(papszTokens);
        if (osID.size() == 0)
        {
            if (nTokens >= 1)
                osID = papszTokens[0];
            else
            {
                CSLDestroy(papszTokens);
                break;
            }
        }
        else
        {
            if (nTokens == 2)
            {
                poLS->addPoint(CPLAtof(papszTokens[0]),
                               CPLAtof(papszTokens[1]));
            }
            else if (nTokens == 3)
            {
                poLS->addPoint(CPLAtof(papszTokens[0]),
                               CPLAtof(papszTokens[1]),
                               CPLAtof(papszTokens[2]));
            }
            else
            {
                CSLDestroy(papszTokens);
//.........这里部分代码省略.........

GDALDataset *XYZDataset::Open( GDALOpenInfo * poOpenInfo )

{
    int         i;
    int         bHasHeaderLine;
    int         nCommentLineCount = 0;

    if (!IdentifyEx(poOpenInfo, bHasHeaderLine, nCommentLineCount))
        return NULL;

    CPLString osFilename(poOpenInfo->pszFilename);

    /*  GZipped .xyz files are common, so automagically open them */
    /*  if the /vsigzip/ has not been explicitly passed */
    if (strlen(poOpenInfo->pszFilename) > 6 &&
        EQUAL(poOpenInfo->pszFilename + strlen(poOpenInfo->pszFilename) - 6, "xyz.gz") &&
        !EQUALN(poOpenInfo->pszFilename, "/vsigzip/", 9))
    {
        osFilename = "/vsigzip/";
        osFilename += poOpenInfo->pszFilename;
    }

/* -------------------------------------------------------------------- */
/*      Find dataset characteristics                                    */
/* -------------------------------------------------------------------- */
    VSILFILE* fp = VSIFOpenL(osFilename.c_str(), "rb");
    if (fp == NULL)
        return NULL;

    /* For better performance of CPLReadLine2L() we create a buffered reader */
    /* (except for /vsigzip/ since it has one internally) */
    if (!EQUALN(poOpenInfo->pszFilename, "/vsigzip/", 9))
        fp = (VSILFILE*) VSICreateBufferedReaderHandle((VSIVirtualHandle*)fp);
    
    const char* pszLine;
    int nXIndex = -1, nYIndex = -1, nZIndex = -1;
    int nMinTokens = 0;

    for(i=0;i<nCommentLineCount;i++)
        CPLReadLine2L(fp, 100, NULL);

/* -------------------------------------------------------------------- */
/*      Parse header line                                               */
/* -------------------------------------------------------------------- */
    if (bHasHeaderLine)
    {
        pszLine = CPLReadLine2L(fp, 100, NULL);
        if (pszLine == NULL)
        {
            VSIFCloseL(fp);
            return NULL;
        }
        char** papszTokens = CSLTokenizeString2( pszLine, " ,\t;",
                                                 CSLT_HONOURSTRINGS );
        int nTokens = CSLCount(papszTokens);
        if (nTokens < 3)
        {
            CPLError(CE_Failure, CPLE_AppDefined,
                     "At line %d, found %d tokens. Expected 3 at least",
                      1, nTokens);
            CSLDestroy(papszTokens);
            VSIFCloseL(fp);
            return NULL;
        }
        int i;
        for(i=0;i<nTokens;i++)
        {
            if (EQUAL(papszTokens[i], "x") ||
                EQUALN(papszTokens[i], "lon", 3) ||
                EQUALN(papszTokens[i], "east", 4))
                nXIndex = i;
            else if (EQUAL(papszTokens[i], "y") ||
                     EQUALN(papszTokens[i], "lat", 3) ||
                     EQUALN(papszTokens[i], "north", 5))
                nYIndex = i;
            else if (EQUAL(papszTokens[i], "z") ||
                     EQUALN(papszTokens[i], "alt", 3) ||
                     EQUAL(papszTokens[i], "height"))
                nZIndex = i;
        }
        CSLDestroy(papszTokens);
        papszTokens = NULL;
        if (nXIndex < 0 || nYIndex < 0 || nZIndex < 0)
        {
            CPLError(CE_Warning, CPLE_AppDefined,
                     "Could not find one of the X, Y or Z column names in header line. Defaulting to the first 3 columns");
            nXIndex = 0;
            nYIndex = 1;
            nZIndex = 2;
        }
        nMinTokens = 1 + MAX(MAX(nXIndex, nYIndex), nZIndex);
    }
    else
    {
        nXIndex = 0;
        nYIndex = 1;
        nZIndex = 2;
        nMinTokens = 3;
    }
    
//.........这里部分代码省略.........