C++ CPLString::empty方法代码示例

//.........这里部分代码省略.........
    oLine.setPoint( 1,
                    dfArrowX2 - dfVec2X*3 - dfVec1X,
                    dfArrowY2 - dfVec2Y*3 - dfVec1Y );
    poMLS->addGeometry( &oLine );

    poFeature->SetGeometryDirectly( poMLS );

    PrepareLineStyle( poFeature );

/* -------------------------------------------------------------------- */
/*      Is the layer disabled/hidden/frozen/off?                        */
/* -------------------------------------------------------------------- */
    CPLString osLayer = poFeature->GetFieldAsString("Layer");

    int bHidden =
        EQUAL(poDS->LookupLayerProperty( osLayer, "Hidden" ), "1");

/* -------------------------------------------------------------------- */
/*      Work out the color for this feature.                            */
/* -------------------------------------------------------------------- */
    int nColor = 256;

    if( oStyleProperties.count("Color") > 0 )
        nColor = atoi(oStyleProperties["Color"]);

    // Use layer color?
    if( nColor < 1 || nColor > 255 )
    {
        const char *pszValue = poDS->LookupLayerProperty( osLayer, "Color" );
        if( pszValue != NULL )
            nColor = atoi(pszValue);
    }

    if( nColor < 1 || nColor > 255 )
        nColor = 8;

/* -------------------------------------------------------------------- */
/*      Prepare a new feature to serve as the dimension text label      */
/*      feature.  We will push it onto the layer as a pending           */
/*      feature for the next feature read.                              */
/* -------------------------------------------------------------------- */

    // a single space suppresses labeling.
    if( osText == " " )
        return poFeature;

    OGRFeature *poLabelFeature = poFeature->Clone();

    poLabelFeature->SetGeometryDirectly( new OGRPoint( oTextPos.x, oTextPos.y ) );

    // Do we need to compute the dimension value?
    if( osText.empty() )
    {
        FormatDimension( osText, POINT_DIST( oArrow1.x, oArrow1.y,
                                             dfArrowX2, dfArrowY2 ) );
    }

    CPLString osStyle;
    char szBuffer[64];
    char* pszComma = NULL;

    osStyle.Printf("LABEL(f:\"Arial\",t:\"%s\",p:5",osText.c_str());

    if( dfAngle != 0.0 )
    {
        CPLsnprintf(szBuffer, sizeof(szBuffer), "%.3g", dfAngle);
        pszComma = strchr(szBuffer, ',');
        if (pszComma)
            *pszComma = '.';
        osStyle += CPLString().Printf(",a:%s", szBuffer);
    }

    if( dfHeight != 0.0 )
    {
        CPLsnprintf(szBuffer, sizeof(szBuffer), "%.3g", dfHeight);
        pszComma = strchr(szBuffer, ',');
        if (pszComma)
            *pszComma = '.';
        osStyle += CPLString().Printf(",s:%sg", szBuffer);
    }

    const unsigned char *pabyDWGColors = ACGetColorTable();

    snprintf( szBuffer, sizeof(szBuffer), ",c:#%02x%02x%02x",
              pabyDWGColors[nColor*3+0],
              pabyDWGColors[nColor*3+1],
              pabyDWGColors[nColor*3+2] );
    osStyle += szBuffer;

    if( bHidden )
        osStyle += "00";

    osStyle += ")";

    poLabelFeature->SetStyleString( osStyle );

    apoPendingFeatures.push( poLabelFeature );

    return poFeature;
}

bool VSIOSSHandleHelper::GetConfiguration(CSLConstList papszOptions,
                                          CPLString& osSecretAccessKey,
                                          CPLString& osAccessKeyId)
{
    osSecretAccessKey = CSLFetchNameValueDef(papszOptions,
        "OSS_SECRET_ACCESS_KEY",
        CPLGetConfigOption("OSS_SECRET_ACCESS_KEY", ""));

    if( !osSecretAccessKey.empty() )
    {
        osAccessKeyId = CSLFetchNameValueDef(papszOptions,
            "OSS_ACCESS_KEY_ID",
            CPLGetConfigOption("OSS_ACCESS_KEY_ID", ""));
        if( osAccessKeyId.empty() )
        {
            VSIError(VSIE_AWSInvalidCredentials,
                    "OSS_ACCESS_KEY_ID configuration option not defined");
            return false;
        }

        return true;
    }

    VSIError(VSIE_AWSInvalidCredentials,
                "OSS_SECRET_ACCESS_KEY configuration option not defined");
    return false;
}

OGRFeature *OGRIDBTableLayer::GetFeature( GIntBig nFeatureId )

{
    if( pszFIDColumn == NULL )
        return OGRIDBLayer::GetFeature( nFeatureId );

    ClearQuery();

    iNextShapeId = nFeatureId;

    poCurr = new ITCursor( *poDS->GetConnection() );

    // Create list of fields
    CPLString osFields;

    if ( poFeatureDefn->GetFieldIndex( pszFIDColumn ) == -1 )
        osFields += pszFIDColumn;

    if ( pszGeomColumn )
    {
        if ( ! osFields.empty() )
            osFields += ",";

        osFields += "st_asbinary(";
        osFields += pszGeomColumn;
        osFields += ") as ";
        osFields += pszGeomColumn;
    }

    for( int i = 0; i < poFeatureDefn->GetFieldCount(); i++ )
    {
        if ( ! osFields.empty() )
            osFields += ",";

        osFields += poFeatureDefn->GetFieldDefn(i)->GetNameRef();
    }

    CPLString sql;

    sql.Printf( "SELECT %s FROM %s WHERE %s = %d",
                osFields.c_str(), poFeatureDefn->GetName(),
                pszFIDColumn, nFeatureId );

    CPLDebug( "OGR_IDB", "ExecuteSQL(%s)", sql.c_str() );
    if( !poCurr->Prepare( sql.c_str() ) ||
        !poCurr->Open(ITCursor::ReadOnly) )
    {
        delete poCurr;
        poCurr = NULL;
        return NULL;
    }

    return GetNextRawFeature();
}

const char *ISIS2Dataset::GetProjectionRef()

{
    if( !osProjection.empty() )
        return osProjection;

    return GDALPamDataset::GetProjectionRef();
}

OGRLayer* OGRPLScenesDataV1Dataset::ParseItemType(json_object* poItemType)
{
    if( poItemType == nullptr || json_object_get_type(poItemType) != json_type_object )
        return nullptr;
    json_object* poId = CPL_json_object_object_get(poItemType, "id");
    if( poId == nullptr || json_object_get_type(poId) != json_type_string )
        return nullptr;

    CPLString osDisplayDescription;
    json_object* poDisplayDescription = CPL_json_object_object_get(poItemType, "display_description");
    if( poDisplayDescription != nullptr && json_object_get_type(poDisplayDescription) == json_type_string )
        osDisplayDescription = json_object_get_string(poDisplayDescription);
    CPLString osDisplayName;
    json_object* poDisplayName = CPL_json_object_object_get(poItemType, "display_name");
    if( poDisplayName != nullptr && json_object_get_type(poDisplayName) == json_type_string )
        osDisplayName = json_object_get_string(poDisplayName);

    const char* pszId = json_object_get_string(poId);

    // The layer might already exist if GetLayerByName() is called before
    // GetLayer()/GetLayerCount() is

    // Prevent GetLayerCount() from calling EstablishLayerList()
    bool bLayerListInitializedBackup = m_bLayerListInitialized;
    m_bLayerListInitialized = true;
    OGRLayer* poExistingLayer = GDALDataset::GetLayerByName(pszId);
    m_bLayerListInitialized = bLayerListInitializedBackup;
    if( poExistingLayer != nullptr )
        return poExistingLayer;

    OGRPLScenesDataV1Layer* poPLLayer = new OGRPLScenesDataV1Layer(
                                                                this, pszId);
    if( !osDisplayName.empty() )
        poPLLayer->SetMetadataItem("SHORT_DESCRIPTION", osDisplayName.c_str());
    if( !osDisplayDescription.empty() )
        poPLLayer->SetMetadataItem("DESCRIPTION", osDisplayDescription.c_str());
    m_papoLayers = (OGRPLScenesDataV1Layer**) CPLRealloc(m_papoLayers,
                                sizeof(OGRPLScenesDataV1Layer*) * (m_nLayers + 1));
    m_papoLayers[m_nLayers ++] = poPLLayer;
    return poPLLayer;
}

// See:
// https://www.alibabacloud.com/help/doc-detail/31951.htm?spm=a3c0i.o31982en.b99.178.5HUTqV
static struct curl_slist*
CPLGetOSSHeaders( const CPLString& osSecretAccessKey,
                  const CPLString& osAccessKeyId,
                  const CPLString& osVerb,
                  const struct curl_slist* psExistingHeaders,
                  const CPLString& osCanonicalizedResource )
{
    CPLString osDate = CPLGetConfigOption("CPL_OSS_TIMESTAMP", "");
    if( osDate.empty() )
    {
        osDate = IVSIS3LikeHandleHelper::GetRFC822DateTime();
    }

    std::map<CPLString, CPLString> oSortedMapHeaders;
    CPLString osCanonicalizedHeaders(
        IVSIS3LikeHandleHelper::BuildCanonicalizedHeaders(
                            oSortedMapHeaders,
                            psExistingHeaders,
                            "x-oss-"));

    CPLString osStringToSign;
    osStringToSign += osVerb + "\n";
    osStringToSign += CPLAWSGetHeaderVal(psExistingHeaders, "Content-MD5") + "\n";
    osStringToSign += CPLAWSGetHeaderVal(psExistingHeaders, "Content-Type") + "\n";
    osStringToSign += osDate + "\n";
    osStringToSign += osCanonicalizedHeaders;
    osStringToSign += osCanonicalizedResource;
#ifdef DEBUG_VERBOSE
    CPLDebug("OSS", "osStringToSign = %s", osStringToSign.c_str());
#endif

/* -------------------------------------------------------------------- */
/*      Build authorization header.                                     */
/* -------------------------------------------------------------------- */

    CPLString osAuthorization("OSS ");
    osAuthorization += osAccessKeyId;
    osAuthorization += ":";
    osAuthorization += GetSignature(osStringToSign, osSecretAccessKey);

#ifdef DEBUG_VERBOSE
    CPLDebug("OSS", "osAuthorization='%s'", osAuthorization.c_str());
#endif

    struct curl_slist *headers=nullptr;
    headers = curl_slist_append(
        headers, CPLSPrintf("Date: %s", osDate.c_str()));
    headers = curl_slist_append(
        headers, CPLSPrintf("Authorization: %s", osAuthorization.c_str()));
    return headers;
}

static bool IsValidXPath(const CPLString& osXPath )
{
    // Check that the XPath syntax belongs to the subset we
    // understand
    bool bOK = !osXPath.empty();
    for(size_t i = 0; i < osXPath.size(); ++i )
    {
        const char chCur = osXPath[i];
        if( chCur == '/' )
        {
            // OK
        }
        else if( chCur == '@' &&
                 (i == 0 || osXPath[i-1] == '/') &&
                 i < osXPath.size()-1 &&
                 isalpha( static_cast<int>(osXPath[i+1]) ) )
        {
            // OK
        }
        else if( chCur == '_' ||
                    isalpha( static_cast<int>(chCur) ) )
        {
            // OK
        }
        else if( isdigit( static_cast<int>(chCur) ) &&
                    i > 0 &&
                    (isalnum( static_cast<int>(osXPath[i-1]) ) ||
                    osXPath[i-1] == '_') )
        {
            // OK
        }
        else if( chCur == ':' &&
                 i > 0 &&
                 (isalnum( static_cast<int>(osXPath[i-1]) ) ||
                  osXPath[i-1] == '_') &&
                 i < osXPath.size()-1 &&
                 isalpha( static_cast<int>(osXPath[i+1]) ) )
        {
            // OK
        }
        else
        {
            bOK = false;
            break;
        }
    }
    return bOK;
}

OGRErr OGRAmigoCloudDataSource::DeleteLayer(int iLayer)
{
    if( !bReadWrite )
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "Operation not available in read-only mode");
        return OGRERR_FAILURE;
    }

    if( iLayer < 0 || iLayer >= nLayers )
    {
        CPLError( CE_Failure, CPLE_AppDefined,
                  "Layer %d not in legal range of 0 to %d.",
                  iLayer, nLayers-1 );
        return OGRERR_FAILURE;
    }

/* -------------------------------------------------------------------- */
/*      Blow away our OGR structures related to the layer.  This is     */
/*      pretty dangerous if anything has a reference to this layer!     */
/* -------------------------------------------------------------------- */
    CPLString osDatasetId = papoLayers[iLayer]->GetDatasetId();

    CPLDebug( "AMIGOCLOUD", "DeleteLayer(%s)", osDatasetId.c_str() );

    int bDeferredCreation = papoLayers[iLayer]->GetDeferredCreation();
    papoLayers[iLayer]->CancelDeferredCreation();
    delete papoLayers[iLayer];
    memmove( papoLayers + iLayer, papoLayers + iLayer + 1,
             sizeof(void *) * (nLayers - iLayer - 1) );
    nLayers--;

    if (osDatasetId.empty())
        return OGRERR_NONE;

    if( !bDeferredCreation )
    {
        std::stringstream url;
        url << std::string(GetAPIURL()) << "/users/0/projects/" + std::string(GetProjectId()) + "/datasets/"+ osDatasetId.c_str();
        if( !RunDELETE(url.str().c_str()) ) {
            return OGRERR_FAILURE;
        }
    }

    return OGRERR_NONE;
}

std::vector<CPLString> GetOutputDriversFor(const char* pszDestFilename,
                                           int nFlagRasterVector)
{
    std::vector<CPLString> aoDriverList;

    CPLString osExt = CPLGetExtension(pszDestFilename);
    const int nDriverCount = GDALGetDriverCount();
    for( int i = 0; i < nDriverCount; i++ )
    {
        GDALDriverH hDriver = GDALGetDriver(i);
        if( (GDALGetMetadataItem( hDriver, GDAL_DCAP_CREATE, nullptr ) != nullptr ||
             GDALGetMetadataItem( hDriver, GDAL_DCAP_CREATECOPY, nullptr ) != nullptr ) &&
            (((nFlagRasterVector & GDAL_OF_RASTER) &&
                GDALGetMetadataItem( hDriver, GDAL_DCAP_RASTER, nullptr ) != nullptr) ||
            ((nFlagRasterVector & GDAL_OF_VECTOR) &&
                GDALGetMetadataItem( hDriver, GDAL_DCAP_VECTOR, nullptr ) != nullptr)) )
        {
            if( !osExt.empty() && DoesDriverHandleExtension(hDriver, osExt) )
            {
                aoDriverList.push_back( GDALGetDriverShortName(hDriver) );
            }
            else
            {
                const char* pszPrefix = GDALGetMetadataItem(hDriver,
                    GDAL_DMD_CONNECTION_PREFIX, nullptr);
                if( pszPrefix && STARTS_WITH_CI(pszDestFilename, pszPrefix) )
                {
                    aoDriverList.push_back( GDALGetDriverShortName(hDriver) );
                }
            }
        }
    }

    // GMT is registered before netCDF for opening reasons, but we want
    // netCDF to be used by default for output.
    if( EQUAL(osExt, "nc") && aoDriverList.size() == 2 &&
        EQUAL(aoDriverList[0], "GMT") && EQUAL(aoDriverList[1], "NETCDF") )
    {
        aoDriverList.clear();
        aoDriverList.push_back("NETCDF");
        aoDriverList.push_back("GMT");
    }

    return aoDriverList;
}

bool GNMRule::CanConnect(const CPLString &soSrcLayerName,
                         const CPLString &soTgtLayerName,
                         const CPLString &soConnLayerName)
{
    if(IsAcceptAny())
        return m_bAllow;

    if(m_soSrcLayerName == soSrcLayerName &&
       m_soTgtLayerName == soTgtLayerName)
    {
        if(soConnLayerName.empty())
            return m_bAllow;
        else
            return m_bAllow && m_soConnLayerName == soConnLayerName;
    }

    return false;
}

OGRErr      OGRDataSourceWithTransaction::DeleteLayer(int iIndex)
{
    if( !m_poBaseDataSource ) return OGRERR_FAILURE;
    OGRLayer* poLayer = GetLayer(iIndex);
    CPLString osName;
    if( poLayer )
        osName = poLayer->GetName();
    OGRErr eErr = m_poBaseDataSource->DeleteLayer(iIndex);
    if( eErr == OGRERR_NONE && !osName.empty() )
    {
        std::map<CPLString, OGRLayerWithTransaction*>::iterator oIter = m_oMapLayers.find(osName);
        if(oIter != m_oMapLayers.end())
        {
            delete oIter->second;
            m_oSetLayers.erase(oIter->second);
            m_oMapLayers.erase(oIter);
        }
    }
    return eErr;
}

VSILFILE *VSIFileFromMemBuffer( const char *pszFilename,
                                GByte *pabyData,
                                vsi_l_offset nDataLength,
                                int bTakeOwnership )

{
    if( VSIFileManager::GetHandler("")
        == VSIFileManager::GetHandler("/vsimem/") )
        VSIInstallMemFileHandler();

    VSIMemFilesystemHandler *poHandler =
        static_cast<VSIMemFilesystemHandler *>(
                VSIFileManager::GetHandler("/vsimem/"));

    if( pszFilename == nullptr )
        return nullptr;

    CPLString osFilename = pszFilename;
    VSIMemFilesystemHandler::NormalizePath( osFilename );
    if( osFilename.empty() )
        return nullptr;

    VSIMemFile *poFile = new VSIMemFile;

    poFile->osFilename = osFilename;
    poFile->bOwnData = CPL_TO_BOOL(bTakeOwnership);
    poFile->pabyData = pabyData;
    poFile->nLength = nDataLength;
    poFile->nAllocLength = nDataLength;

    {
        CPLMutexHolder oHolder( &poHandler->hMutex );
        poHandler->Unlink_unlocked(osFilename);
        poHandler->oFileList[poFile->osFilename] = poFile;
        CPLAtomicInc(&(poFile->nRefCount));
    }

    // TODO(schwehr): Fix this so that the using statement is not needed.
    // Will just adding the bool for bSetError be okay?
    return reinterpret_cast<VSILFILE *>( poHandler->Open( osFilename, "r+" ) );
}

/**
 * CPLStrip()
 */
CPLString CPLStrip(const CPLString& sString, const char cChar)
{
    if(sString.empty())
        return sString;

    size_t dCopyFrom = 0;
    size_t dCopyCount = sString.size();

    if (sString[0] == cChar)
    {
        dCopyFrom++;
        dCopyCount--;
    }

    if (sString[sString.size() - 1] == cChar)
        dCopyCount--;

    if(dCopyCount == 0)
        return CPLString();
    
    return sString.substr(dCopyFrom, dCopyCount);
}

int ROIPACDataset::Identify( GDALOpenInfo *poOpenInfo )
{
/* -------------------------------------------------------------------- */
/*      Check if:                                                       */
/*      * 1. The data file extension is known                           */
/* -------------------------------------------------------------------- */
    const char *pszExtension = CPLGetExtension(poOpenInfo->pszFilename);
    if ( strcmp( pszExtension, "raw" ) == 0 )
    {
        /* Since gdal do not read natively CInt8, more work is needed
         * to read raw files */
        return false;
    }
    bool bExtensionIsValid = strcmp( pszExtension, "int" ) == 0
                               || strcmp( pszExtension, "slc" ) == 0
                               || strcmp( pszExtension, "amp" ) == 0
                               || strcmp( pszExtension, "cor" ) == 0
                               || strcmp( pszExtension, "hgt" ) == 0
                               || strcmp( pszExtension, "unw" ) == 0
                               || strcmp( pszExtension, "msk" ) == 0
                               || strcmp( pszExtension, "trans" ) == 0
                               || strcmp( pszExtension, "dem" ) == 0
                               || strcmp( pszExtension, "flg" ) == 0;
    if ( !bExtensionIsValid )
    {
        return false;
    }

/* -------------------------------------------------------------------- */
/*      * 2. there is a .rsc file                                      */
/* -------------------------------------------------------------------- */
    CPLString osRscFilename = getRscFilename( poOpenInfo );
    if ( osRscFilename.empty() )
    {
        return false;
    }

    return true;
}

CPLString VSIOSSHandleHelper::BuildURL(const CPLString& osEndpoint,
                                       const CPLString& osBucket,
                                       const CPLString& osObjectKey,
                                       bool bUseHTTPS, bool bUseVirtualHosting)
{
    const char* pszProtocol = (bUseHTTPS) ? "https" : "http";
    if( osBucket.empty()  )
    {
        return CPLSPrintf("%s://%s", pszProtocol,
                          osEndpoint.c_str());
    }
    else if( bUseVirtualHosting )
        return CPLSPrintf("%s://%s.%s/%s", pszProtocol,
                                        osBucket.c_str(),
                                        osEndpoint.c_str(),
                                        CPLAWSURLEncode(osObjectKey, false).c_str());
    else
        return CPLSPrintf("%s://%s/%s/%s", pszProtocol,
                                        osEndpoint.c_str(),
                                        osBucket.c_str(),
                                        CPLAWSURLEncode(osObjectKey, false).c_str());
}