LCOV - code coverage report
Current view: top level - frmts/vrt - vrtderivedrasterband.cpp (source / functions) Hit Total Coverage
Test: gdal_filtered.info Lines: 576 618 93.2 %
Date: 2024-11-21 22:18:42 Functions: 28 30 93.3 %

          Line data    Source code
       1             : /******************************************************************************
       2             :  *
       3             :  * Project:  Virtual GDAL Datasets
       4             :  * Purpose:  Implementation of a sourced raster band that derives its raster
       5             :  *           by applying an algorithm (GDALDerivedPixelFunc) to the sources.
       6             :  * Author:   Pete Nagy
       7             :  *
       8             :  ******************************************************************************
       9             :  * Copyright (c) 2005 Vexcel Corp.
      10             :  * Copyright (c) 2008-2011, Even Rouault <even dot rouault at spatialys.com>
      11             :  *
      12             :  * SPDX-License-Identifier: MIT
      13             :  *****************************************************************************/
      14             : 
      15             : #include "cpl_minixml.h"
      16             : #include "cpl_string.h"
      17             : #include "vrtdataset.h"
      18             : #include "cpl_multiproc.h"
      19             : #include "gdalpython.h"
      20             : 
      21             : #include <algorithm>
      22             : #include <map>
      23             : #include <vector>
      24             : #include <utility>
      25             : 
      26             : /*! @cond Doxygen_Suppress */
      27             : 
      28             : using namespace GDALPy;
      29             : 
      30             : // #define GDAL_VRT_DISABLE_PYTHON
      31             : 
      32             : #ifndef GDAL_VRT_ENABLE_PYTHON_DEFAULT
      33             : // Can be YES, NO or TRUSTED_MODULES
      34             : #define GDAL_VRT_ENABLE_PYTHON_DEFAULT "TRUSTED_MODULES"
      35             : #endif
      36             : 
      37             : /* Flags for getting buffers */
      38             : #define PyBUF_WRITABLE 0x0001
      39             : #define PyBUF_FORMAT 0x0004
      40             : #define PyBUF_ND 0x0008
      41             : #define PyBUF_STRIDES (0x0010 | PyBUF_ND)
      42             : #define PyBUF_INDIRECT (0x0100 | PyBUF_STRIDES)
      43             : #define PyBUF_FULL (PyBUF_INDIRECT | PyBUF_WRITABLE | PyBUF_FORMAT)
      44             : 
      45             : /************************************************************************/
      46             : /*                        GDALCreateNumpyArray()                        */
      47             : /************************************************************************/
      48             : 
      49         393 : static PyObject *GDALCreateNumpyArray(PyObject *pCreateArray, void *pBuffer,
      50             :                                       GDALDataType eType, int nHeight,
      51             :                                       int nWidth)
      52             : {
      53             :     PyObject *poPyBuffer;
      54             :     const size_t nSize =
      55         393 :         static_cast<size_t>(nHeight) * nWidth * GDALGetDataTypeSizeBytes(eType);
      56             :     Py_buffer pybuffer;
      57         393 :     if (PyBuffer_FillInfo(&pybuffer, nullptr, static_cast<char *>(pBuffer),
      58         393 :                           nSize, 0, PyBUF_FULL) != 0)
      59             :     {
      60           0 :         return nullptr;
      61             :     }
      62         393 :     poPyBuffer = PyMemoryView_FromBuffer(&pybuffer);
      63         393 :     PyObject *pArgsCreateArray = PyTuple_New(4);
      64         393 :     PyTuple_SetItem(pArgsCreateArray, 0, poPyBuffer);
      65         393 :     const char *pszDataType = nullptr;
      66         393 :     switch (eType)
      67             :     {
      68         358 :         case GDT_Byte:
      69         358 :             pszDataType = "uint8";
      70         358 :             break;
      71           2 :         case GDT_Int8:
      72           2 :             pszDataType = "int8";
      73           2 :             break;
      74           3 :         case GDT_UInt16:
      75           3 :             pszDataType = "uint16";
      76           3 :             break;
      77           8 :         case GDT_Int16:
      78           8 :             pszDataType = "int16";
      79           8 :             break;
      80           3 :         case GDT_UInt32:
      81           3 :             pszDataType = "uint32";
      82           3 :             break;
      83           3 :         case GDT_Int32:
      84           3 :             pszDataType = "int32";
      85           3 :             break;
      86           2 :         case GDT_Int64:
      87           2 :             pszDataType = "int64";
      88           2 :             break;
      89           2 :         case GDT_UInt64:
      90           2 :             pszDataType = "uint64";
      91           2 :             break;
      92           3 :         case GDT_Float32:
      93           3 :             pszDataType = "float32";
      94           3 :             break;
      95           3 :         case GDT_Float64:
      96           3 :             pszDataType = "float64";
      97           3 :             break;
      98           0 :         case GDT_CInt16:
      99             :         case GDT_CInt32:
     100           0 :             CPLAssert(FALSE);
     101             :             break;
     102           3 :         case GDT_CFloat32:
     103           3 :             pszDataType = "complex64";
     104           3 :             break;
     105           3 :         case GDT_CFloat64:
     106           3 :             pszDataType = "complex128";
     107           3 :             break;
     108           0 :         case GDT_Unknown:
     109             :         case GDT_TypeCount:
     110           0 :             CPLAssert(FALSE);
     111             :             break;
     112             :     }
     113         393 :     PyTuple_SetItem(
     114             :         pArgsCreateArray, 1,
     115             :         PyBytes_FromStringAndSize(pszDataType, strlen(pszDataType)));
     116         393 :     PyTuple_SetItem(pArgsCreateArray, 2, PyLong_FromLong(nHeight));
     117         393 :     PyTuple_SetItem(pArgsCreateArray, 3, PyLong_FromLong(nWidth));
     118             :     PyObject *poNumpyArray =
     119         393 :         PyObject_Call(pCreateArray, pArgsCreateArray, nullptr);
     120         393 :     Py_DecRef(pArgsCreateArray);
     121         393 :     if (PyErr_Occurred())
     122           0 :         PyErr_Print();
     123         393 :     return poNumpyArray;
     124             : }
     125             : 
     126             : /************************************************************************/
     127             : /* ==================================================================== */
     128             : /*                     VRTDerivedRasterBandPrivateData                  */
     129             : /* ==================================================================== */
     130             : /************************************************************************/
     131             : 
     132             : class VRTDerivedRasterBandPrivateData
     133             : {
     134             :     VRTDerivedRasterBandPrivateData(const VRTDerivedRasterBandPrivateData &) =
     135             :         delete;
     136             :     VRTDerivedRasterBandPrivateData &
     137             :     operator=(const VRTDerivedRasterBandPrivateData &) = delete;
     138             : 
     139             :   public:
     140             :     CPLString m_osCode{};
     141             :     CPLString m_osLanguage = "C";
     142             :     int m_nBufferRadius = 0;
     143             :     PyObject *m_poGDALCreateNumpyArray = nullptr;
     144             :     PyObject *m_poUserFunction = nullptr;
     145             :     bool m_bPythonInitializationDone = false;
     146             :     bool m_bPythonInitializationSuccess = false;
     147             :     bool m_bExclusiveLock = false;
     148             :     bool m_bFirstTime = true;
     149             :     std::vector<std::pair<CPLString, CPLString>> m_oFunctionArgs{};
     150             :     bool m_bSkipNonContributingSourcesSpecified = false;
     151             :     bool m_bSkipNonContributingSources = false;
     152             : 
     153         184 :     VRTDerivedRasterBandPrivateData() = default;
     154             : 
     155         368 :     virtual ~VRTDerivedRasterBandPrivateData()
     156         184 :     {
     157         184 :         if (m_poGDALCreateNumpyArray)
     158          43 :             Py_DecRef(m_poGDALCreateNumpyArray);
     159         184 :         if (m_poUserFunction)
     160          44 :             Py_DecRef(m_poUserFunction);
     161         368 :     }
     162             : };
     163             : 
     164             : /************************************************************************/
     165             : /* ==================================================================== */
     166             : /*                          VRTDerivedRasterBand                        */
     167             : /* ==================================================================== */
     168             : /************************************************************************/
     169             : 
     170             : /************************************************************************/
     171             : /*                        VRTDerivedRasterBand()                        */
     172             : /************************************************************************/
     173             : 
     174         163 : VRTDerivedRasterBand::VRTDerivedRasterBand(GDALDataset *poDSIn, int nBandIn)
     175             :     : VRTSourcedRasterBand(poDSIn, nBandIn), m_poPrivate(nullptr),
     176         163 :       pszFuncName(nullptr), eSourceTransferType(GDT_Unknown)
     177             : {
     178         163 :     m_poPrivate = new VRTDerivedRasterBandPrivateData;
     179         163 : }
     180             : 
     181             : /************************************************************************/
     182             : /*                        VRTDerivedRasterBand()                        */
     183             : /************************************************************************/
     184             : 
     185          21 : VRTDerivedRasterBand::VRTDerivedRasterBand(GDALDataset *poDSIn, int nBandIn,
     186             :                                            GDALDataType eType, int nXSize,
     187          21 :                                            int nYSize)
     188             :     : VRTSourcedRasterBand(poDSIn, nBandIn, eType, nXSize, nYSize),
     189             :       m_poPrivate(nullptr), pszFuncName(nullptr),
     190          21 :       eSourceTransferType(GDT_Unknown)
     191             : {
     192          21 :     m_poPrivate = new VRTDerivedRasterBandPrivateData;
     193          21 : }
     194             : 
     195             : /************************************************************************/
     196             : /*                       ~VRTDerivedRasterBand()                        */
     197             : /************************************************************************/
     198             : 
     199         368 : VRTDerivedRasterBand::~VRTDerivedRasterBand()
     200             : 
     201             : {
     202         184 :     CPLFree(pszFuncName);
     203         184 :     delete m_poPrivate;
     204         368 : }
     205             : 
     206             : /************************************************************************/
     207             : /*                               Cleanup()                              */
     208             : /************************************************************************/
     209             : 
     210         933 : void VRTDerivedRasterBand::Cleanup()
     211             : {
     212         933 : }
     213             : 
     214             : /************************************************************************/
     215             : /*                      GetGlobalMapPixelFunction()                     */
     216             : /************************************************************************/
     217             : 
     218             : static std::map<std::string,
     219             :                 std::pair<VRTDerivedRasterBand::PixelFunc, std::string>> &
     220       36286 : GetGlobalMapPixelFunction()
     221             : {
     222             :     static std::map<std::string,
     223             :                     std::pair<VRTDerivedRasterBand::PixelFunc, std::string>>
     224       36286 :         gosMapPixelFunction;
     225       36286 :     return gosMapPixelFunction;
     226             : }
     227             : 
     228             : /************************************************************************/
     229             : /*                           AddPixelFunction()                         */
     230             : /************************************************************************/
     231             : 
     232             : /*! @endcond */
     233             : 
     234             : /**
     235             :  * This adds a pixel function to the global list of available pixel
     236             :  * functions for derived bands.  Pixel functions must be registered
     237             :  * in this way before a derived band tries to access data.
     238             :  *
     239             :  * Derived bands are stored with only the name of the pixel function
     240             :  * that it will apply, and if a pixel function matching the name is not
     241             :  * found the IRasterIO() call will do nothing.
     242             :  *
     243             :  * @param pszName Name used to access pixel function
     244             :  * @param pfnNewFunction Pixel function associated with name.  An
     245             :  *  existing pixel function registered with the same name will be
     246             :  *  replaced with the new one.
     247             :  *
     248             :  * @return CE_None, invalid (NULL) parameters are currently ignored.
     249             :  */
     250       19382 : CPLErr CPL_STDCALL GDALAddDerivedBandPixelFunc(
     251             :     const char *pszName, GDALDerivedPixelFunc pfnNewFunction)
     252             : {
     253       19382 :     if (pszName == nullptr || pszName[0] == '\0' || pfnNewFunction == nullptr)
     254             :     {
     255           0 :         return CE_None;
     256             :     }
     257             : 
     258       38764 :     GetGlobalMapPixelFunction()[pszName] = {
     259          58 :         [pfnNewFunction](void **papoSources, int nSources, void *pData,
     260             :                          int nBufXSize, int nBufYSize, GDALDataType eSrcType,
     261             :                          GDALDataType eBufType, int nPixelSpace, int nLineSpace,
     262          58 :                          CSLConstList papszFunctionArgs)
     263             :         {
     264             :             (void)papszFunctionArgs;
     265          58 :             return pfnNewFunction(papoSources, nSources, pData, nBufXSize,
     266             :                                   nBufYSize, eSrcType, eBufType, nPixelSpace,
     267          58 :                                   nLineSpace);
     268             :         },
     269       58146 :         ""};
     270             : 
     271       19382 :     return CE_None;
     272             : }
     273             : 
     274             : /**
     275             :  * This adds a pixel function to the global list of available pixel
     276             :  * functions for derived bands.  Pixel functions must be registered
     277             :  * in this way before a derived band tries to access data.
     278             :  *
     279             :  * Derived bands are stored with only the name of the pixel function
     280             :  * that it will apply, and if a pixel function matching the name is not
     281             :  * found the IRasterIO() call will do nothing.
     282             :  *
     283             :  * @param pszName Name used to access pixel function
     284             :  * @param pfnNewFunction Pixel function associated with name.  An
     285             :  *  existing pixel function registered with the same name will be
     286             :  *  replaced with the new one.
     287             :  * @param pszMetadata Pixel function metadata (not currently implemented)
     288             :  *
     289             :  * @return CE_None, invalid (NULL) parameters are currently ignored.
     290             :  * @since GDAL 3.4
     291             :  */
     292       16798 : CPLErr CPL_STDCALL GDALAddDerivedBandPixelFuncWithArgs(
     293             :     const char *pszName, GDALDerivedPixelFuncWithArgs pfnNewFunction,
     294             :     const char *pszMetadata)
     295             : {
     296       16798 :     if (!pszName || pszName[0] == '\0' || !pfnNewFunction)
     297             :     {
     298           0 :         return CE_None;
     299             :     }
     300             : 
     301       33596 :     GetGlobalMapPixelFunction()[pszName] = {pfnNewFunction,
     302       50394 :                                             pszMetadata ? pszMetadata : ""};
     303             : 
     304       16798 :     return CE_None;
     305             : }
     306             : 
     307             : /*! @cond Doxygen_Suppress */
     308             : 
     309             : /**
     310             :  * This adds a pixel function to the global list of available pixel
     311             :  * functions for derived bands.
     312             :  *
     313             :  * This is the same as the C function GDALAddDerivedBandPixelFunc()
     314             :  *
     315             :  * @param pszFuncNameIn Name used to access pixel function
     316             :  * @param pfnNewFunction Pixel function associated with name.  An
     317             :  *  existing pixel function registered with the same name will be
     318             :  *  replaced with the new one.
     319             :  *
     320             :  * @return CE_None, invalid (NULL) parameters are currently ignored.
     321             :  */
     322             : CPLErr
     323           0 : VRTDerivedRasterBand::AddPixelFunction(const char *pszFuncNameIn,
     324             :                                        GDALDerivedPixelFunc pfnNewFunction)
     325             : {
     326           0 :     return GDALAddDerivedBandPixelFunc(pszFuncNameIn, pfnNewFunction);
     327             : }
     328             : 
     329           0 : CPLErr VRTDerivedRasterBand::AddPixelFunction(
     330             :     const char *pszFuncNameIn, GDALDerivedPixelFuncWithArgs pfnNewFunction,
     331             :     const char *pszMetadata)
     332             : {
     333           0 :     return GDALAddDerivedBandPixelFuncWithArgs(pszFuncNameIn, pfnNewFunction,
     334           0 :                                                pszMetadata);
     335             : }
     336             : 
     337             : /************************************************************************/
     338             : /*                           GetPixelFunction()                         */
     339             : /************************************************************************/
     340             : 
     341             : /**
     342             :  * Get a pixel function previously registered using the global
     343             :  * AddPixelFunction.
     344             :  *
     345             :  * @param pszFuncNameIn The name associated with the pixel function.
     346             :  *
     347             :  * @return A derived band pixel function, or NULL if none have been
     348             :  * registered for pszFuncName.
     349             :  */
     350             : const std::pair<VRTDerivedRasterBand::PixelFunc, std::string> *
     351         106 : VRTDerivedRasterBand::GetPixelFunction(const char *pszFuncNameIn)
     352             : {
     353         106 :     if (pszFuncNameIn == nullptr || pszFuncNameIn[0] == '\0')
     354             :     {
     355           0 :         return nullptr;
     356             :     }
     357             : 
     358         106 :     const auto &oMapPixelFunction = GetGlobalMapPixelFunction();
     359         106 :     const auto oIter = oMapPixelFunction.find(pszFuncNameIn);
     360             : 
     361         106 :     if (oIter == oMapPixelFunction.end())
     362           1 :         return nullptr;
     363             : 
     364         105 :     return &(oIter->second);
     365             : }
     366             : 
     367             : /************************************************************************/
     368             : /*                         SetPixelFunctionName()                       */
     369             : /************************************************************************/
     370             : 
     371             : /**
     372             :  * Set the pixel function name to be applied to this derived band.  The
     373             :  * name should match a pixel function registered using AddPixelFunction.
     374             :  *
     375             :  * @param pszFuncNameIn Name of pixel function to be applied to this derived
     376             :  * band.
     377             :  */
     378         185 : void VRTDerivedRasterBand::SetPixelFunctionName(const char *pszFuncNameIn)
     379             : {
     380         185 :     CPLFree(pszFuncName);
     381         185 :     pszFuncName = CPLStrdup(pszFuncNameIn);
     382         185 : }
     383             : 
     384             : /************************************************************************/
     385             : /*                         SetPixelFunctionLanguage()                   */
     386             : /************************************************************************/
     387             : 
     388             : /**
     389             :  * Set the language of the pixel function.
     390             :  *
     391             :  * @param pszLanguage Language of the pixel function (only "C" and "Python"
     392             :  * are supported currently)
     393             :  * @since GDAL 2.3
     394             :  */
     395           1 : void VRTDerivedRasterBand::SetPixelFunctionLanguage(const char *pszLanguage)
     396             : {
     397           1 :     m_poPrivate->m_osLanguage = pszLanguage;
     398           1 : }
     399             : 
     400             : /************************************************************************/
     401             : /*                         SetSourceTransferType()                      */
     402             : /************************************************************************/
     403             : 
     404             : /**
     405             :  * Set the transfer type to be used to obtain pixel information from
     406             :  * all of the sources.  If unset, the transfer type used will be the
     407             :  * same as the derived band data type.  This makes it possible, for
     408             :  * example, to pass CFloat32 source pixels to the pixel function, even
     409             :  * if the pixel function generates a raster for a derived band that
     410             :  * is of type Byte.
     411             :  *
     412             :  * @param eDataTypeIn Data type to use to obtain pixel information from
     413             :  * the sources to be passed to the derived band pixel function.
     414             :  */
     415          18 : void VRTDerivedRasterBand::SetSourceTransferType(GDALDataType eDataTypeIn)
     416             : {
     417          18 :     eSourceTransferType = eDataTypeIn;
     418          18 : }
     419             : 
     420             : /************************************************************************/
     421             : /*                           InitializePython()                         */
     422             : /************************************************************************/
     423             : 
     424         379 : bool VRTDerivedRasterBand::InitializePython()
     425             : {
     426         379 :     if (m_poPrivate->m_bPythonInitializationDone)
     427         321 :         return m_poPrivate->m_bPythonInitializationSuccess;
     428             : 
     429          58 :     m_poPrivate->m_bPythonInitializationDone = true;
     430          58 :     m_poPrivate->m_bPythonInitializationSuccess = false;
     431             : 
     432         116 :     const CPLString osPythonFullname(pszFuncName ? pszFuncName : "");
     433          58 :     const size_t nIdxDot = osPythonFullname.rfind(".");
     434         116 :     CPLString osPythonModule;
     435         116 :     CPLString osPythonFunction;
     436          58 :     if (nIdxDot != std::string::npos)
     437             :     {
     438          25 :         osPythonModule = osPythonFullname.substr(0, nIdxDot);
     439          25 :         osPythonFunction = osPythonFullname.substr(nIdxDot + 1);
     440             :     }
     441             :     else
     442             :     {
     443          33 :         osPythonFunction = osPythonFullname;
     444             :     }
     445             : 
     446             : #ifndef GDAL_VRT_DISABLE_PYTHON
     447             :     const char *pszPythonEnabled =
     448          58 :         CPLGetConfigOption("GDAL_VRT_ENABLE_PYTHON", nullptr);
     449             : #else
     450             :     const char *pszPythonEnabled = "NO";
     451             : #endif
     452             :     const CPLString osPythonEnabled(
     453         116 :         pszPythonEnabled ? pszPythonEnabled : GDAL_VRT_ENABLE_PYTHON_DEFAULT);
     454             : 
     455          58 :     if (EQUAL(osPythonEnabled, "TRUSTED_MODULES"))
     456             :     {
     457          12 :         bool bIsTrustedModule = false;
     458             :         const CPLString osVRTTrustedModules(
     459          12 :             CPLGetConfigOption("GDAL_VRT_PYTHON_TRUSTED_MODULES", ""));
     460          12 :         if (!osPythonModule.empty())
     461             :         {
     462             :             char **papszTrustedModules =
     463          10 :                 CSLTokenizeString2(osVRTTrustedModules, ",", 0);
     464          23 :             for (char **papszIter = papszTrustedModules;
     465          23 :                  !bIsTrustedModule && papszIter && *papszIter; ++papszIter)
     466             :             {
     467          13 :                 const char *pszIterModule = *papszIter;
     468          13 :                 size_t nIterModuleLen = strlen(pszIterModule);
     469          13 :                 if (nIterModuleLen > 2 &&
     470          12 :                     strncmp(pszIterModule + nIterModuleLen - 2, ".*", 2) == 0)
     471             :                 {
     472           2 :                     bIsTrustedModule =
     473           2 :                         (strncmp(osPythonModule, pszIterModule,
     474           3 :                                  nIterModuleLen - 2) == 0) &&
     475           1 :                         (osPythonModule.size() == nIterModuleLen - 2 ||
     476           0 :                          (osPythonModule.size() >= nIterModuleLen &&
     477           0 :                           osPythonModule[nIterModuleLen - 1] == '.'));
     478             :                 }
     479          11 :                 else if (nIterModuleLen >= 1 &&
     480          11 :                          pszIterModule[nIterModuleLen - 1] == '*')
     481             :                 {
     482           4 :                     bIsTrustedModule = (strncmp(osPythonModule, pszIterModule,
     483             :                                                 nIterModuleLen - 1) == 0);
     484             :                 }
     485             :                 else
     486             :                 {
     487           7 :                     bIsTrustedModule =
     488           7 :                         (strcmp(osPythonModule, pszIterModule) == 0);
     489             :                 }
     490             :             }
     491          10 :             CSLDestroy(papszTrustedModules);
     492             :         }
     493             : 
     494          12 :         if (!bIsTrustedModule)
     495             :         {
     496           7 :             if (osPythonModule.empty())
     497             :             {
     498           2 :                 CPLError(
     499             :                     CE_Failure, CPLE_AppDefined,
     500             :                     "Python code needs to be executed, but it uses inline code "
     501             :                     "in the VRT whereas the current policy is to trust only "
     502             :                     "code from external trusted modules (defined in the "
     503             :                     "GDAL_VRT_PYTHON_TRUSTED_MODULES configuration option). "
     504             :                     "If you trust the code in %s, you can set the "
     505             :                     "GDAL_VRT_ENABLE_PYTHON configuration option to YES.",
     506           2 :                     GetDataset() ? GetDataset()->GetDescription()
     507             :                                  : "(unknown VRT)");
     508             :             }
     509           5 :             else if (osVRTTrustedModules.empty())
     510             :             {
     511           2 :                 CPLError(
     512             :                     CE_Failure, CPLE_AppDefined,
     513             :                     "Python code needs to be executed, but it uses code "
     514             :                     "from module '%s', whereas the current policy is to "
     515             :                     "trust only code from modules defined in the "
     516             :                     "GDAL_VRT_PYTHON_TRUSTED_MODULES configuration option, "
     517             :                     "which is currently unset. "
     518             :                     "If you trust the code in '%s', you can add module '%s' "
     519             :                     "to GDAL_VRT_PYTHON_TRUSTED_MODULES (or set the "
     520             :                     "GDAL_VRT_ENABLE_PYTHON configuration option to YES).",
     521             :                     osPythonModule.c_str(),
     522           1 :                     GetDataset() ? GetDataset()->GetDescription()
     523             :                                  : "(unknown VRT)",
     524             :                     osPythonModule.c_str());
     525             :             }
     526             :             else
     527             :             {
     528           8 :                 CPLError(
     529             :                     CE_Failure, CPLE_AppDefined,
     530             :                     "Python code needs to be executed, but it uses code "
     531             :                     "from module '%s', whereas the current policy is to "
     532             :                     "trust only code from modules '%s' (defined in the "
     533             :                     "GDAL_VRT_PYTHON_TRUSTED_MODULES configuration option). "
     534             :                     "If you trust the code in '%s', you can add module '%s' "
     535             :                     "to GDAL_VRT_PYTHON_TRUSTED_MODULES (or set the "
     536             :                     "GDAL_VRT_ENABLE_PYTHON configuration option to YES).",
     537             :                     osPythonModule.c_str(), osVRTTrustedModules.c_str(),
     538           4 :                     GetDataset() ? GetDataset()->GetDescription()
     539             :                                  : "(unknown VRT)",
     540             :                     osPythonModule.c_str());
     541             :             }
     542           7 :             return false;
     543             :         }
     544             :     }
     545             : 
     546             : #ifdef disabled_because_this_is_probably_broken_by_design
     547             :     // See https://lwn.net/Articles/574215/
     548             :     // and http://nedbatchelder.com/blog/201206/eval_really_is_dangerous.html
     549             :     else if (EQUAL(osPythonEnabled, "IF_SAFE"))
     550             :     {
     551             :         bool bSafe = true;
     552             :         // If the function comes from another module, then we don't know
     553             :         if (!osPythonModule.empty())
     554             :         {
     555             :             CPLDebug("VRT", "Python function is from another module");
     556             :             bSafe = false;
     557             :         }
     558             : 
     559             :         CPLString osCode(m_poPrivate->m_osCode);
     560             : 
     561             :         // Reject all imports except a few trusted modules
     562             :         const char *const apszTrustedImports[] = {
     563             :             "import math",
     564             :             "from math import",
     565             :             "import numpy",  // caution: numpy has lots of I/O functions !
     566             :             "from numpy import",
     567             :             // TODO: not sure if importing arbitrary stuff from numba is OK
     568             :             // so let's just restrict to jit.
     569             :             "from numba import jit",
     570             : 
     571             :             // Not imports but still whitelisted, whereas other __ is banned
     572             :             "__init__",
     573             :             "__call__",
     574             :         };
     575             :         for (size_t i = 0; i < CPL_ARRAYSIZE(apszTrustedImports); ++i)
     576             :         {
     577             :             osCode.replaceAll(CPLString(apszTrustedImports[i]), "");
     578             :         }
     579             : 
     580             :         // Some dangerous built-in functions or numpy functions
     581             :         const char *const apszUntrusted[] = {
     582             :             "import",  // and __import__
     583             :             "eval",       "compile", "open",
     584             :             "load",        // reload, numpy.load
     585             :             "file",        // and exec_file, numpy.fromfile, numpy.tofile
     586             :             "input",       // and raw_input
     587             :             "save",        // numpy.save
     588             :             "memmap",      // numpy.memmap
     589             :             "DataSource",  // numpy.DataSource
     590             :             "genfromtxt",  // numpy.genfromtxt
     591             :             "getattr",
     592             :             "ctypeslib",  // numpy.ctypeslib
     593             :             "testing",    // numpy.testing
     594             :             "dump",       // numpy.ndarray.dump
     595             :             "fromregex",  // numpy.fromregex
     596             :             "__"};
     597             :         for (size_t i = 0; i < CPL_ARRAYSIZE(apszUntrusted); ++i)
     598             :         {
     599             :             if (osCode.find(apszUntrusted[i]) != std::string::npos)
     600             :             {
     601             :                 CPLDebug("VRT", "Found '%s' word in Python code",
     602             :                          apszUntrusted[i]);
     603             :                 bSafe = false;
     604             :             }
     605             :         }
     606             : 
     607             :         if (!bSafe)
     608             :         {
     609             :             CPLError(CE_Failure, CPLE_AppDefined,
     610             :                      "Python code needs to be executed, but we cannot verify "
     611             :                      "if it is safe, so this is disabled by default. "
     612             :                      "If you trust the code in %s, you can set the "
     613             :                      "GDAL_VRT_ENABLE_PYTHON configuration option to YES.",
     614             :                      GetDataset() ? GetDataset()->GetDescription()
     615             :                                   : "(unknown VRT)");
     616             :             return false;
     617             :         }
     618             :     }
     619             : #endif  // disabled_because_this_is_probably_broken_by_design
     620             : 
     621          47 :     else if (!EQUAL(osPythonEnabled, "YES") && !EQUAL(osPythonEnabled, "ON") &&
     622           1 :              !EQUAL(osPythonEnabled, "TRUE"))
     623             :     {
     624           1 :         if (pszPythonEnabled == nullptr)
     625             :         {
     626             :             // Note: this is dead code with our current default policy
     627             :             // GDAL_VRT_ENABLE_PYTHON == "TRUSTED_MODULES"
     628           0 :             CPLError(CE_Failure, CPLE_AppDefined,
     629             :                      "Python code needs to be executed, but this is "
     630             :                      "disabled by default. If you trust the code in %s, "
     631             :                      "you can set the GDAL_VRT_ENABLE_PYTHON configuration "
     632             :                      "option to YES.",
     633           0 :                      GetDataset() ? GetDataset()->GetDescription()
     634             :                                   : "(unknown VRT)");
     635             :         }
     636             :         else
     637             :         {
     638           1 :             CPLError(
     639             :                 CE_Failure, CPLE_AppDefined,
     640             :                 "Python code in %s needs to be executed, but this has been "
     641             :                 "explicitly disabled.",
     642           1 :                 GetDataset() ? GetDataset()->GetDescription()
     643             :                              : "(unknown VRT)");
     644             :         }
     645           1 :         return false;
     646             :     }
     647             : 
     648          50 :     if (!GDALPythonInitialize())
     649           2 :         return false;
     650             : 
     651             :     // Whether we should just use our own global mutex, in addition to Python
     652             :     // GIL locking.
     653          96 :     m_poPrivate->m_bExclusiveLock =
     654          48 :         CPLTestBool(CPLGetConfigOption("GDAL_VRT_PYTHON_EXCLUSIVE_LOCK", "NO"));
     655             : 
     656             :     // numba jit'ification doesn't seem to be thread-safe, so force use of
     657             :     // lock now and at first execution of function. Later executions seem to
     658             :     // be thread-safe. This problem doesn't seem to appear for code in
     659             :     // regular files
     660             :     const bool bUseExclusiveLock =
     661          96 :         m_poPrivate->m_bExclusiveLock ||
     662          48 :         m_poPrivate->m_osCode.find("@jit") != std::string::npos;
     663          96 :     GIL_Holder oHolder(bUseExclusiveLock);
     664             : 
     665             :     // As we don't want to depend on numpy C API/ABI, we use a trick to build
     666             :     // a numpy array object. We define a Python function to which we pass a
     667             :     // Python buffer object.
     668             : 
     669             :     // We need to build a unique module name, otherwise this will crash in
     670             :     // multithreaded use cases.
     671          96 :     CPLString osModuleName(CPLSPrintf("gdal_vrt_module_%p", this));
     672          96 :     PyObject *poCompiledString = Py_CompileString(
     673             :         ("import numpy\n"
     674             :          "def GDALCreateNumpyArray(buffer, dtype, height, width):\n"
     675             :          "    return numpy.frombuffer(buffer, str(dtype.decode('ascii')))."
     676             :          "reshape([height, width])\n"
     677          48 :          "\n" +
     678          48 :          m_poPrivate->m_osCode)
     679             :             .c_str(),
     680             :         osModuleName, Py_file_input);
     681          48 :     if (poCompiledString == nullptr || PyErr_Occurred())
     682             :     {
     683           1 :         CPLError(CE_Failure, CPLE_AppDefined, "Couldn't compile code:\n%s",
     684           2 :                  GetPyExceptionString().c_str());
     685           1 :         return false;
     686             :     }
     687             :     PyObject *poModule =
     688          47 :         PyImport_ExecCodeModule(osModuleName, poCompiledString);
     689          47 :     Py_DecRef(poCompiledString);
     690             : 
     691          47 :     if (poModule == nullptr || PyErr_Occurred())
     692             :     {
     693           1 :         CPLError(CE_Failure, CPLE_AppDefined, "%s",
     694           2 :                  GetPyExceptionString().c_str());
     695           1 :         return false;
     696             :     }
     697             : 
     698             :     // Fetch user computation function
     699          46 :     if (!osPythonModule.empty())
     700             :     {
     701          20 :         PyObject *poUserModule = PyImport_ImportModule(osPythonModule);
     702          20 :         if (poUserModule == nullptr || PyErr_Occurred())
     703             :         {
     704           1 :             CPLString osException = GetPyExceptionString();
     705           1 :             if (!osException.empty() && osException.back() == '\n')
     706             :             {
     707           1 :                 osException.pop_back();
     708             :             }
     709           1 :             if (osException.find("ModuleNotFoundError") == 0)
     710             :             {
     711           1 :                 osException += ". You may need to define PYTHONPATH";
     712             :             }
     713           1 :             CPLError(CE_Failure, CPLE_AppDefined, "%s", osException.c_str());
     714           1 :             Py_DecRef(poModule);
     715           1 :             return false;
     716             :         }
     717          38 :         m_poPrivate->m_poUserFunction =
     718          19 :             PyObject_GetAttrString(poUserModule, osPythonFunction);
     719          19 :         Py_DecRef(poUserModule);
     720             :     }
     721             :     else
     722             :     {
     723          52 :         m_poPrivate->m_poUserFunction =
     724          26 :             PyObject_GetAttrString(poModule, osPythonFunction);
     725             :     }
     726          45 :     if (m_poPrivate->m_poUserFunction == nullptr || PyErr_Occurred())
     727             :     {
     728           1 :         CPLError(CE_Failure, CPLE_AppDefined, "%s",
     729           2 :                  GetPyExceptionString().c_str());
     730           1 :         Py_DecRef(poModule);
     731           1 :         return false;
     732             :     }
     733          44 :     if (!PyCallable_Check(m_poPrivate->m_poUserFunction))
     734             :     {
     735           1 :         CPLError(CE_Failure, CPLE_AppDefined, "Object '%s' is not callable",
     736             :                  osPythonFunction.c_str());
     737           1 :         Py_DecRef(poModule);
     738           1 :         return false;
     739             :     }
     740             : 
     741             :     // Fetch our GDALCreateNumpyArray python function
     742          86 :     m_poPrivate->m_poGDALCreateNumpyArray =
     743          43 :         PyObject_GetAttrString(poModule, "GDALCreateNumpyArray");
     744          43 :     if (m_poPrivate->m_poGDALCreateNumpyArray == nullptr || PyErr_Occurred())
     745             :     {
     746             :         // Shouldn't happen normally...
     747           0 :         CPLError(CE_Failure, CPLE_AppDefined, "%s",
     748           0 :                  GetPyExceptionString().c_str());
     749           0 :         Py_DecRef(poModule);
     750           0 :         return false;
     751             :     }
     752          43 :     Py_DecRef(poModule);
     753             : 
     754          43 :     m_poPrivate->m_bPythonInitializationSuccess = true;
     755          43 :     return true;
     756             : }
     757             : 
     758          46 : CPLErr VRTDerivedRasterBand::GetPixelFunctionArguments(
     759             :     const CPLString &osMetadata,
     760             :     std::vector<std::pair<CPLString, CPLString>> &oAdditionalArgs)
     761             : {
     762             : 
     763          92 :     auto poArgs = CPLXMLTreeCloser(CPLParseXMLString(osMetadata));
     764          92 :     if (poArgs != nullptr && poArgs->eType == CXT_Element &&
     765          46 :         !strcmp(poArgs->pszValue, "PixelFunctionArgumentsList"))
     766             :     {
     767         117 :         for (CPLXMLNode *psIter = poArgs->psChild; psIter != nullptr;
     768          71 :              psIter = psIter->psNext)
     769             :         {
     770          72 :             if (psIter->eType == CXT_Element &&
     771          72 :                 !strcmp(psIter->pszValue, "Argument"))
     772             :             {
     773          72 :                 CPLString osName, osType, osValue;
     774          72 :                 auto pszName = CPLGetXMLValue(psIter, "name", nullptr);
     775          72 :                 if (pszName != nullptr)
     776          61 :                     osName = pszName;
     777          72 :                 auto pszType = CPLGetXMLValue(psIter, "type", nullptr);
     778          72 :                 if (pszType != nullptr)
     779          72 :                     osType = pszType;
     780          72 :                 auto pszValue = CPLGetXMLValue(psIter, "value", nullptr);
     781          72 :                 if (pszValue != nullptr)
     782          16 :                     osValue = pszValue;
     783          72 :                 if (osType == "constant" && osValue != "" && osName != "")
     784           1 :                     oAdditionalArgs.push_back(
     785           2 :                         std::pair<CPLString, CPLString>(osName, osValue));
     786          72 :                 if (osType == "builtin")
     787             :                 {
     788             :                     double dfVal;
     789             :                     int success;
     790          11 :                     if (osValue == "NoData")
     791           8 :                         dfVal = this->GetNoDataValue(&success);
     792           3 :                     else if (osValue == "scale")
     793           2 :                         dfVal = this->GetScale(&success);
     794           1 :                     else if (osValue == "offset")
     795           1 :                         dfVal = this->GetOffset(&success);
     796             :                     else
     797             :                     {
     798           0 :                         CPLError(CE_Failure, CPLE_NotSupported,
     799             :                                  "PixelFunction builtin %s not supported",
     800             :                                  osValue.c_str());
     801           1 :                         return CE_Failure;
     802             :                     }
     803          11 :                     if (!success)
     804             :                     {
     805           2 :                         if (CPLTestBool(
     806             :                                 CPLGetXMLValue(psIter, "optional", "false")))
     807           1 :                             continue;
     808             : 
     809           1 :                         CPLError(CE_Failure, CPLE_AppDefined,
     810             :                                  "Raster has no %s", osValue.c_str());
     811           1 :                         return CE_Failure;
     812             :                     }
     813             : 
     814           9 :                     oAdditionalArgs.push_back(std::pair<CPLString, CPLString>(
     815           9 :                         osValue, CPLSPrintf("%.17g", dfVal)));
     816           9 :                     CPLDebug("VRT",
     817             :                              "Added builtin pixel function argument %s = %s",
     818             :                              osValue.c_str(), CPLSPrintf("%.17g", dfVal));
     819             :                 }
     820             :             }
     821             :         }
     822             :     }
     823             : 
     824          45 :     return CE_None;
     825             : }
     826             : 
     827             : /************************************************************************/
     828             : /*                             IRasterIO()                              */
     829             : /************************************************************************/
     830             : 
     831             : /**
     832             :  * Read/write a region of image data for this band.
     833             :  *
     834             :  * Each of the sources for this derived band will be read and passed to
     835             :  * the derived band pixel function.  The pixel function is responsible
     836             :  * for applying whatever algorithm is necessary to generate this band's
     837             :  * pixels from the sources.
     838             :  *
     839             :  * The sources will be read using the transfer type specified for sources
     840             :  * using SetSourceTransferType().  If no transfer type has been set for
     841             :  * this derived band, the band's data type will be used as the transfer type.
     842             :  *
     843             :  * @see gdalrasterband
     844             :  *
     845             :  * @param eRWFlag Either GF_Read to read a region of data, or GT_Write to
     846             :  * write a region of data.
     847             :  *
     848             :  * @param nXOff The pixel offset to the top left corner of the region
     849             :  * of the band to be accessed.  This would be zero to start from the left side.
     850             :  *
     851             :  * @param nYOff The line offset to the top left corner of the region
     852             :  * of the band to be accessed.  This would be zero to start from the top.
     853             :  *
     854             :  * @param nXSize The width of the region of the band to be accessed in pixels.
     855             :  *
     856             :  * @param nYSize The height of the region of the band to be accessed in lines.
     857             :  *
     858             :  * @param pData The buffer into which the data should be read, or from which
     859             :  * it should be written.  This buffer must contain at least nBufXSize *
     860             :  * nBufYSize words of type eBufType.  It is organized in left to right,
     861             :  * top to bottom pixel order.  Spacing is controlled by the nPixelSpace,
     862             :  * and nLineSpace parameters.
     863             :  *
     864             :  * @param nBufXSize The width of the buffer image into which the desired
     865             :  * region is to be read, or from which it is to be written.
     866             :  *
     867             :  * @param nBufYSize The height of the buffer image into which the desired
     868             :  * region is to be read, or from which it is to be written.
     869             :  *
     870             :  * @param eBufType The type of the pixel values in the pData data buffer.  The
     871             :  * pixel values will automatically be translated to/from the GDALRasterBand
     872             :  * data type as needed.
     873             :  *
     874             :  * @param nPixelSpace The byte offset from the start of one pixel value in
     875             :  * pData to the start of the next pixel value within a scanline.  If defaulted
     876             :  * (0) the size of the datatype eBufType is used.
     877             :  *
     878             :  * @param nLineSpace The byte offset from the start of one scanline in
     879             :  * pData to the start of the next.  If defaulted the size of the datatype
     880             :  * eBufType * nBufXSize is used.
     881             :  *
     882             :  * @return CE_Failure if the access fails, otherwise CE_None.
     883             :  */
     884         493 : CPLErr VRTDerivedRasterBand::IRasterIO(
     885             :     GDALRWFlag eRWFlag, int nXOff, int nYOff, int nXSize, int nYSize,
     886             :     void *pData, int nBufXSize, int nBufYSize, GDALDataType eBufType,
     887             :     GSpacing nPixelSpace, GSpacing nLineSpace, GDALRasterIOExtraArg *psExtraArg)
     888             : {
     889         493 :     if (eRWFlag == GF_Write)
     890             :     {
     891           1 :         CPLError(CE_Failure, CPLE_AppDefined,
     892             :                  "Writing through VRTSourcedRasterBand is not supported.");
     893           1 :         return CE_Failure;
     894             :     }
     895             : 
     896         492 :     const int nBufTypeSize = GDALGetDataTypeSizeBytes(eBufType);
     897         492 :     GDALDataType eSrcType = eSourceTransferType;
     898         492 :     if (eSrcType == GDT_Unknown || eSrcType >= GDT_TypeCount)
     899             :     {
     900         409 :         eSrcType = eBufType;
     901             :     }
     902         492 :     const int nSrcTypeSize = GDALGetDataTypeSizeBytes(eSrcType);
     903             : 
     904             :     /* -------------------------------------------------------------------- */
     905             :     /*      Initialize the buffer to some background value. Use the         */
     906             :     /*      nodata value if available.                                      */
     907             :     /* -------------------------------------------------------------------- */
     908         492 :     if (SkipBufferInitialization())
     909             :     {
     910             :         // Do nothing
     911             :     }
     912         437 :     else if (nPixelSpace == nBufTypeSize &&
     913         437 :              (!m_bNoDataValueSet || m_dfNoDataValue == 0))
     914             :     {
     915         436 :         memset(pData, 0,
     916         436 :                static_cast<size_t>(nBufXSize) * nBufYSize * nBufTypeSize);
     917             :     }
     918           1 :     else if (m_bNoDataValueSet)
     919             :     {
     920           1 :         double dfWriteValue = m_dfNoDataValue;
     921             : 
     922          51 :         for (int iLine = 0; iLine < nBufYSize; iLine++)
     923             :         {
     924          50 :             GDALCopyWords(&dfWriteValue, GDT_Float64, 0,
     925          50 :                           static_cast<GByte *>(pData) + nLineSpace * iLine,
     926             :                           eBufType, static_cast<int>(nPixelSpace), nBufXSize);
     927             :         }
     928             :     }
     929             : 
     930             :     /* -------------------------------------------------------------------- */
     931             :     /*      Do we have overviews that would be appropriate to satisfy       */
     932             :     /*      this request?                                                   */
     933             :     /* -------------------------------------------------------------------- */
     934         492 :     if ((nBufXSize < nXSize || nBufYSize < nYSize) && GetOverviewCount() > 0)
     935             :     {
     936           0 :         if (OverviewRasterIO(eRWFlag, nXOff, nYOff, nXSize, nYSize, pData,
     937             :                              nBufXSize, nBufYSize, eBufType, nPixelSpace,
     938           0 :                              nLineSpace, psExtraArg) == CE_None)
     939           0 :             return CE_None;
     940             :     }
     941             : 
     942             :     /* ---- Get pixel function for band ---- */
     943         492 :     const std::pair<PixelFunc, std::string> *poPixelFunc = nullptr;
     944         984 :     std::vector<std::pair<CPLString, CPLString>> oAdditionalArgs;
     945             : 
     946         492 :     if (EQUAL(m_poPrivate->m_osLanguage, "C"))
     947             :     {
     948         106 :         poPixelFunc = VRTDerivedRasterBand::GetPixelFunction(pszFuncName);
     949         106 :         if (poPixelFunc == nullptr)
     950             :         {
     951           1 :             CPLError(CE_Failure, CPLE_IllegalArg,
     952             :                      "VRTDerivedRasterBand::IRasterIO:"
     953             :                      "Derived band pixel function '%s' not registered.",
     954             :                      this->pszFuncName);
     955           1 :             return CE_Failure;
     956             :         }
     957             : 
     958         105 :         if (poPixelFunc->second != "")
     959             :         {
     960          92 :             if (GetPixelFunctionArguments(poPixelFunc->second,
     961          46 :                                           oAdditionalArgs) != CE_None)
     962             :             {
     963           1 :                 return CE_Failure;
     964             :             }
     965             :         }
     966             :     }
     967             : 
     968             :     /* TODO: It would be nice to use a MallocBlock function for each
     969             :        individual buffer that would recycle blocks of memory from a
     970             :        cache by reassigning blocks that are nearly the same size.
     971             :        A corresponding FreeBlock might only truly free if the total size
     972             :        of freed blocks gets to be too great of a percentage of the size
     973             :        of the allocated blocks. */
     974             : 
     975             :     // Get buffers for each source.
     976         490 :     const int nBufferRadius = m_poPrivate->m_nBufferRadius;
     977         490 :     if (nBufferRadius > (INT_MAX - nBufXSize) / 2 ||
     978         490 :         nBufferRadius > (INT_MAX - nBufYSize) / 2)
     979             :     {
     980           0 :         return CE_Failure;
     981             :     }
     982         490 :     const int nExtBufXSize = nBufXSize + 2 * nBufferRadius;
     983         490 :     const int nExtBufYSize = nBufYSize + 2 * nBufferRadius;
     984         490 :     int nBufferCount = 0;
     985             :     void **pBuffers =
     986         490 :         static_cast<void **>(CPLMalloc(sizeof(void *) * nSources));
     987         980 :     std::vector<int> anMapBufferIdxToSourceIdx(nSources);
     988         667 :     for (int iSource = 0; iSource < nSources; iSource++)
     989             :     {
     990         185 :         if (m_poPrivate->m_bSkipNonContributingSources &&
     991           8 :             papoSources[iSource]->IsSimpleSource())
     992             :         {
     993           8 :             bool bError = false;
     994             :             double dfReqXOff, dfReqYOff, dfReqXSize, dfReqYSize;
     995             :             int nReqXOff, nReqYOff, nReqXSize, nReqYSize;
     996             :             int nOutXOff, nOutYOff, nOutXSize, nOutYSize;
     997           8 :             auto poSource =
     998           8 :                 static_cast<VRTSimpleSource *>(papoSources[iSource]);
     999           8 :             if (!poSource->GetSrcDstWindow(
    1000             :                     nXOff, nYOff, nXSize, nYSize, nBufXSize, nBufYSize,
    1001             :                     &dfReqXOff, &dfReqYOff, &dfReqXSize, &dfReqYSize, &nReqXOff,
    1002             :                     &nReqYOff, &nReqXSize, &nReqYSize, &nOutXOff, &nOutYOff,
    1003             :                     &nOutXSize, &nOutYSize, bError))
    1004             :             {
    1005           4 :                 if (bError)
    1006             :                 {
    1007           0 :                     for (int i = 0; i < nBufferCount; i++)
    1008             :                     {
    1009           0 :                         VSIFree(pBuffers[i]);
    1010             :                     }
    1011           0 :                     CPLFree(pBuffers);
    1012           0 :                     return CE_Failure;
    1013             :                 }
    1014             : 
    1015             :                 // Skip non contributing source
    1016           4 :                 continue;
    1017             :             }
    1018             :         }
    1019             : 
    1020         173 :         anMapBufferIdxToSourceIdx[nBufferCount] = iSource;
    1021         346 :         pBuffers[nBufferCount] =
    1022         173 :             VSI_MALLOC3_VERBOSE(nSrcTypeSize, nExtBufXSize, nExtBufYSize);
    1023         173 :         if (pBuffers[nBufferCount] == nullptr)
    1024             :         {
    1025           0 :             for (int i = 0; i < nBufferCount; i++)
    1026             :             {
    1027           0 :                 VSIFree(pBuffers[i]);
    1028             :             }
    1029           0 :             CPLFree(pBuffers);
    1030           0 :             return CE_Failure;
    1031             :         }
    1032             : 
    1033             :         /* ------------------------------------------------------------ */
    1034             :         /* #4045: Initialize the newly allocated buffers before handing */
    1035             :         /* them off to the sources. These buffers are packed, so we     */
    1036             :         /* don't need any special line-by-line handling when a nonzero  */
    1037             :         /* nodata value is set.                                         */
    1038             :         /* ------------------------------------------------------------ */
    1039         173 :         if (!m_bNoDataValueSet || m_dfNoDataValue == 0)
    1040             :         {
    1041         170 :             memset(pBuffers[nBufferCount], 0,
    1042         170 :                    static_cast<size_t>(nSrcTypeSize) * nExtBufXSize *
    1043         170 :                        nExtBufYSize);
    1044             :         }
    1045             :         else
    1046             :         {
    1047           3 :             GDALCopyWords(&m_dfNoDataValue, GDT_Float64, 0,
    1048           3 :                           static_cast<GByte *>(pBuffers[nBufferCount]),
    1049             :                           eSrcType, nSrcTypeSize, nExtBufXSize * nExtBufYSize);
    1050             :         }
    1051             : 
    1052         173 :         ++nBufferCount;
    1053             :     }
    1054             : 
    1055             :     // No contributing sources and SkipNonContributingSources mode ?
    1056             :     // Do not call the pixel function and just return the 0/nodata initialized
    1057             :     // output buffer.
    1058         490 :     if (nBufferCount == 0 && m_poPrivate->m_bSkipNonContributingSources)
    1059             :     {
    1060           1 :         CPLFree(pBuffers);
    1061           1 :         return CE_None;
    1062             :     }
    1063             : 
    1064             :     GDALRasterIOExtraArg sExtraArg;
    1065         489 :     GDALCopyRasterIOExtraArg(&sExtraArg, psExtraArg);
    1066             : 
    1067         489 :     int nXShiftInBuffer = 0;
    1068         489 :     int nYShiftInBuffer = 0;
    1069         489 :     int nExtBufXSizeReq = nExtBufXSize;
    1070         489 :     int nExtBufYSizeReq = nExtBufYSize;
    1071             : 
    1072         489 :     int nXOffExt = nXOff;
    1073         489 :     int nYOffExt = nYOff;
    1074         489 :     int nXSizeExt = nXSize;
    1075         489 :     int nYSizeExt = nYSize;
    1076             : 
    1077         489 :     if (nBufferRadius)
    1078             :     {
    1079           9 :         double dfXRatio = static_cast<double>(nXSize) / nBufXSize;
    1080           9 :         double dfYRatio = static_cast<double>(nYSize) / nBufYSize;
    1081             : 
    1082           9 :         if (!sExtraArg.bFloatingPointWindowValidity)
    1083             :         {
    1084           9 :             sExtraArg.dfXOff = nXOff;
    1085           9 :             sExtraArg.dfYOff = nYOff;
    1086           9 :             sExtraArg.dfXSize = nXSize;
    1087           9 :             sExtraArg.dfYSize = nYSize;
    1088             :         }
    1089             : 
    1090           9 :         sExtraArg.dfXOff -= dfXRatio * nBufferRadius;
    1091           9 :         sExtraArg.dfYOff -= dfYRatio * nBufferRadius;
    1092           9 :         sExtraArg.dfXSize += 2 * dfXRatio * nBufferRadius;
    1093           9 :         sExtraArg.dfYSize += 2 * dfYRatio * nBufferRadius;
    1094           9 :         if (sExtraArg.dfXOff < 0)
    1095             :         {
    1096           9 :             nXShiftInBuffer = -static_cast<int>(sExtraArg.dfXOff / dfXRatio);
    1097           9 :             nExtBufXSizeReq -= nXShiftInBuffer;
    1098           9 :             sExtraArg.dfXSize += sExtraArg.dfXOff;
    1099           9 :             sExtraArg.dfXOff = 0;
    1100             :         }
    1101           9 :         if (sExtraArg.dfYOff < 0)
    1102             :         {
    1103           9 :             nYShiftInBuffer = -static_cast<int>(sExtraArg.dfYOff / dfYRatio);
    1104           9 :             nExtBufYSizeReq -= nYShiftInBuffer;
    1105           9 :             sExtraArg.dfYSize += sExtraArg.dfYOff;
    1106           9 :             sExtraArg.dfYOff = 0;
    1107             :         }
    1108           9 :         if (sExtraArg.dfXOff + sExtraArg.dfXSize > nRasterXSize)
    1109             :         {
    1110           9 :             nExtBufXSizeReq -= static_cast<int>(
    1111           9 :                 (sExtraArg.dfXOff + sExtraArg.dfXSize - nRasterXSize) /
    1112             :                 dfXRatio);
    1113           9 :             sExtraArg.dfXSize = nRasterXSize - sExtraArg.dfXOff;
    1114             :         }
    1115           9 :         if (sExtraArg.dfYOff + sExtraArg.dfYSize > nRasterYSize)
    1116             :         {
    1117           9 :             nExtBufYSizeReq -= static_cast<int>(
    1118           9 :                 (sExtraArg.dfYOff + sExtraArg.dfYSize - nRasterYSize) /
    1119             :                 dfYRatio);
    1120           9 :             sExtraArg.dfYSize = nRasterYSize - sExtraArg.dfYOff;
    1121             :         }
    1122             : 
    1123           9 :         nXOffExt = static_cast<int>(sExtraArg.dfXOff);
    1124           9 :         nYOffExt = static_cast<int>(sExtraArg.dfYOff);
    1125          18 :         nXSizeExt = std::min(static_cast<int>(sExtraArg.dfXSize + 0.5),
    1126           9 :                              nRasterXSize - nXOffExt);
    1127          18 :         nYSizeExt = std::min(static_cast<int>(sExtraArg.dfYSize + 0.5),
    1128           9 :                              nRasterYSize - nYOffExt);
    1129             :     }
    1130             : 
    1131             :     // Load values for sources into packed buffers.
    1132         489 :     CPLErr eErr = CE_None;
    1133         489 :     VRTSource::WorkingState oWorkingState;
    1134         662 :     for (int iBuffer = 0; iBuffer < nBufferCount && eErr == CE_None; iBuffer++)
    1135             :     {
    1136         173 :         const int iSource = anMapBufferIdxToSourceIdx[iBuffer];
    1137         173 :         GByte *pabyBuffer = static_cast<GByte *>(pBuffers[iBuffer]);
    1138         173 :         eErr = static_cast<VRTSource *>(papoSources[iSource])
    1139         346 :                    ->RasterIO(
    1140             :                        eSrcType, nXOffExt, nYOffExt, nXSizeExt, nYSizeExt,
    1141         173 :                        pabyBuffer +
    1142         173 :                            (nYShiftInBuffer * nExtBufXSize + nXShiftInBuffer) *
    1143             :                                nSrcTypeSize,
    1144             :                        nExtBufXSizeReq, nExtBufYSizeReq, eSrcType, nSrcTypeSize,
    1145         173 :                        static_cast<GSpacing>(nSrcTypeSize) * nExtBufXSize,
    1146         173 :                        &sExtraArg, oWorkingState);
    1147             : 
    1148             :         // Extend first lines
    1149         182 :         for (int iY = 0; iY < nYShiftInBuffer; iY++)
    1150             :         {
    1151           9 :             memcpy(pabyBuffer +
    1152           9 :                        static_cast<size_t>(iY) * nExtBufXSize * nSrcTypeSize,
    1153           9 :                    pabyBuffer + static_cast<size_t>(nYShiftInBuffer) *
    1154           9 :                                     nExtBufXSize * nSrcTypeSize,
    1155           9 :                    static_cast<size_t>(nExtBufXSize) * nSrcTypeSize);
    1156             :         }
    1157             :         // Extend last lines
    1158         182 :         for (int iY = nYShiftInBuffer + nExtBufYSizeReq; iY < nExtBufYSize;
    1159             :              iY++)
    1160             :         {
    1161           9 :             memcpy(pabyBuffer +
    1162           9 :                        static_cast<size_t>(iY) * nExtBufXSize * nSrcTypeSize,
    1163           9 :                    pabyBuffer + static_cast<size_t>(nYShiftInBuffer +
    1164           9 :                                                     nExtBufYSizeReq - 1) *
    1165           9 :                                     nExtBufXSize * nSrcTypeSize,
    1166           9 :                    static_cast<size_t>(nExtBufXSize) * nSrcTypeSize);
    1167             :         }
    1168             :         // Extend first cols
    1169         173 :         if (nXShiftInBuffer)
    1170             :         {
    1171        1116 :             for (int iY = 0; iY < nExtBufYSize; iY++)
    1172             :             {
    1173        2214 :                 for (int iX = 0; iX < nXShiftInBuffer; iX++)
    1174             :                 {
    1175        1107 :                     memcpy(pabyBuffer +
    1176        1107 :                                static_cast<size_t>(iY * nExtBufXSize + iX) *
    1177        1107 :                                    nSrcTypeSize,
    1178        1107 :                            pabyBuffer +
    1179        1107 :                                (static_cast<size_t>(iY) * nExtBufXSize +
    1180        1107 :                                 nXShiftInBuffer) *
    1181        1107 :                                    nSrcTypeSize,
    1182             :                            nSrcTypeSize);
    1183             :                 }
    1184             :             }
    1185             :         }
    1186             :         // Extent last cols
    1187         173 :         if (nXShiftInBuffer + nExtBufXSizeReq < nExtBufXSize)
    1188             :         {
    1189        1116 :             for (int iY = 0; iY < nExtBufYSize; iY++)
    1190             :             {
    1191        1107 :                 for (int iX = nXShiftInBuffer + nExtBufXSizeReq;
    1192        2214 :                      iX < nExtBufXSize; iX++)
    1193             :                 {
    1194        1107 :                     memcpy(pabyBuffer +
    1195        1107 :                                (static_cast<size_t>(iY) * nExtBufXSize + iX) *
    1196        1107 :                                    nSrcTypeSize,
    1197        1107 :                            pabyBuffer +
    1198        1107 :                                (static_cast<size_t>(iY) * nExtBufXSize +
    1199        1107 :                                 nXShiftInBuffer + nExtBufXSizeReq - 1) *
    1200        1107 :                                    nSrcTypeSize,
    1201             :                            nSrcTypeSize);
    1202             :                 }
    1203             :             }
    1204             :         }
    1205             :     }
    1206             : 
    1207             :     // Apply pixel function.
    1208         489 :     if (eErr == CE_None && EQUAL(m_poPrivate->m_osLanguage, "Python"))
    1209             :     {
    1210         385 :         eErr = CE_Failure;
    1211             : 
    1212             :         // numpy doesn't have native cint16/cint32
    1213         385 :         if (eSrcType == GDT_CInt16 || eSrcType == GDT_CInt32)
    1214             :         {
    1215           2 :             CPLError(
    1216             :                 CE_Failure, CPLE_AppDefined,
    1217             :                 "CInt16/CInt32 data type not supported for SourceTransferType");
    1218           2 :             goto end;
    1219             :         }
    1220         383 :         if (eDataType == GDT_CInt16 || eDataType == GDT_CInt32)
    1221             :         {
    1222           4 :             CPLError(CE_Failure, CPLE_AppDefined,
    1223             :                      "CInt16/CInt32 data type not supported for data type");
    1224           4 :             goto end;
    1225             :         }
    1226             : 
    1227         379 :         if (!InitializePython())
    1228          15 :             goto end;
    1229             : 
    1230         364 :         GByte *pabyTmpBuffer = nullptr;
    1231             :         // Do we need a temporary buffer or can we use directly the output
    1232             :         // buffer ?
    1233         364 :         if (nBufferRadius != 0 || eDataType != eBufType ||
    1234          24 :             nPixelSpace != nBufTypeSize ||
    1235          24 :             nLineSpace != static_cast<GSpacing>(nBufTypeSize) * nBufXSize)
    1236             :         {
    1237         340 :             pabyTmpBuffer = static_cast<GByte *>(VSI_CALLOC_VERBOSE(
    1238             :                 static_cast<size_t>(nExtBufXSize) * nExtBufYSize,
    1239             :                 GDALGetDataTypeSizeBytes(eDataType)));
    1240         340 :             if (!pabyTmpBuffer)
    1241           0 :                 goto end;
    1242             :         }
    1243             : 
    1244             :         {
    1245             :             const bool bUseExclusiveLock =
    1246         728 :                 m_poPrivate->m_bExclusiveLock ||
    1247         407 :                 (m_poPrivate->m_bFirstTime &&
    1248          43 :                  m_poPrivate->m_osCode.find("@jit") != std::string::npos);
    1249         364 :             m_poPrivate->m_bFirstTime = false;
    1250         364 :             GIL_Holder oHolder(bUseExclusiveLock);
    1251             : 
    1252             :             // Prepare target numpy array
    1253             :             PyObject *poPyDstArray =
    1254         364 :                 GDALCreateNumpyArray(m_poPrivate->m_poGDALCreateNumpyArray,
    1255             :                                      pabyTmpBuffer ? pabyTmpBuffer : pData,
    1256             :                                      eDataType, nExtBufYSize, nExtBufXSize);
    1257         364 :             if (!poPyDstArray)
    1258             :             {
    1259           0 :                 VSIFree(pabyTmpBuffer);
    1260           0 :                 goto end;
    1261             :             }
    1262             : 
    1263             :             // Wrap source buffers as input numpy arrays
    1264         364 :             PyObject *pyArgInputArray = PyTuple_New(nBufferCount);
    1265         393 :             for (int i = 0; i < nBufferCount; i++)
    1266             :             {
    1267          29 :                 GByte *pabyBuffer = static_cast<GByte *>(pBuffers[i]);
    1268          58 :                 PyObject *poPySrcArray = GDALCreateNumpyArray(
    1269          29 :                     m_poPrivate->m_poGDALCreateNumpyArray, pabyBuffer, eSrcType,
    1270             :                     nExtBufYSize, nExtBufXSize);
    1271          29 :                 CPLAssert(poPySrcArray);
    1272          29 :                 PyTuple_SetItem(pyArgInputArray, i, poPySrcArray);
    1273             :             }
    1274             : 
    1275             :             // Create arguments
    1276         364 :             PyObject *pyArgs = PyTuple_New(10);
    1277         364 :             PyTuple_SetItem(pyArgs, 0, pyArgInputArray);
    1278         364 :             PyTuple_SetItem(pyArgs, 1, poPyDstArray);
    1279         364 :             PyTuple_SetItem(pyArgs, 2, PyLong_FromLong(nXOff));
    1280         364 :             PyTuple_SetItem(pyArgs, 3, PyLong_FromLong(nYOff));
    1281         364 :             PyTuple_SetItem(pyArgs, 4, PyLong_FromLong(nXSize));
    1282         364 :             PyTuple_SetItem(pyArgs, 5, PyLong_FromLong(nYSize));
    1283         364 :             PyTuple_SetItem(pyArgs, 6, PyLong_FromLong(nRasterXSize));
    1284         364 :             PyTuple_SetItem(pyArgs, 7, PyLong_FromLong(nRasterYSize));
    1285         364 :             PyTuple_SetItem(pyArgs, 8, PyLong_FromLong(nBufferRadius));
    1286             : 
    1287             :             double adfGeoTransform[6];
    1288         364 :             adfGeoTransform[0] = 0;
    1289         364 :             adfGeoTransform[1] = 1;
    1290         364 :             adfGeoTransform[2] = 0;
    1291         364 :             adfGeoTransform[3] = 0;
    1292         364 :             adfGeoTransform[4] = 0;
    1293         364 :             adfGeoTransform[5] = 1;
    1294         364 :             if (GetDataset())
    1295         364 :                 GetDataset()->GetGeoTransform(adfGeoTransform);
    1296         364 :             PyObject *pyGT = PyTuple_New(6);
    1297        2548 :             for (int i = 0; i < 6; i++)
    1298        2184 :                 PyTuple_SetItem(pyGT, i,
    1299             :                                 PyFloat_FromDouble(adfGeoTransform[i]));
    1300         364 :             PyTuple_SetItem(pyArgs, 9, pyGT);
    1301             : 
    1302             :             // Prepare kwargs
    1303         364 :             PyObject *pyKwargs = PyDict_New();
    1304         374 :             for (size_t i = 0; i < m_poPrivate->m_oFunctionArgs.size(); ++i)
    1305             :             {
    1306             :                 const char *pszKey =
    1307          10 :                     m_poPrivate->m_oFunctionArgs[i].first.c_str();
    1308             :                 const char *pszValue =
    1309          10 :                     m_poPrivate->m_oFunctionArgs[i].second.c_str();
    1310          10 :                 PyDict_SetItemString(
    1311             :                     pyKwargs, pszKey,
    1312             :                     PyBytes_FromStringAndSize(pszValue, strlen(pszValue)));
    1313             :             }
    1314             : 
    1315             :             // Call user function
    1316             :             PyObject *pRetValue =
    1317         364 :                 PyObject_Call(m_poPrivate->m_poUserFunction, pyArgs, pyKwargs);
    1318             : 
    1319         364 :             Py_DecRef(pyArgs);
    1320         364 :             Py_DecRef(pyKwargs);
    1321             : 
    1322         364 :             if (ErrOccurredEmitCPLError())
    1323             :             {
    1324             :                 // do nothing
    1325             :             }
    1326             :             else
    1327             :             {
    1328         362 :                 eErr = CE_None;
    1329             :             }
    1330         364 :             if (pRetValue)
    1331         362 :                 Py_DecRef(pRetValue);
    1332             :         }  // End of GIL section
    1333             : 
    1334         364 :         if (pabyTmpBuffer)
    1335             :         {
    1336             :             // Copy numpy destination array to user buffer
    1337       41177 :             for (int iY = 0; iY < nBufYSize; iY++)
    1338             :             {
    1339             :                 size_t nSrcOffset =
    1340       40837 :                     (static_cast<size_t>(iY + nBufferRadius) * nExtBufXSize +
    1341       40837 :                      nBufferRadius) *
    1342       40837 :                     GDALGetDataTypeSizeBytes(eDataType);
    1343       40830 :                 GDALCopyWords(pabyTmpBuffer + nSrcOffset, eDataType,
    1344             :                               GDALGetDataTypeSizeBytes(eDataType),
    1345       40824 :                               static_cast<GByte *>(pData) + iY * nLineSpace,
    1346             :                               eBufType, static_cast<int>(nPixelSpace),
    1347             :                               nBufXSize);
    1348             :             }
    1349             : 
    1350         340 :             VSIFree(pabyTmpBuffer);
    1351             :         }
    1352             :     }
    1353         104 :     else if (eErr == CE_None && poPixelFunc != nullptr)
    1354             :     {
    1355         104 :         char **papszArgs = nullptr;
    1356             : 
    1357         104 :         oAdditionalArgs.insert(oAdditionalArgs.end(),
    1358         104 :                                m_poPrivate->m_oFunctionArgs.begin(),
    1359         208 :                                m_poPrivate->m_oFunctionArgs.end());
    1360         152 :         for (const auto &oArg : oAdditionalArgs)
    1361             :         {
    1362          48 :             const char *pszKey = oArg.first.c_str();
    1363          48 :             const char *pszValue = oArg.second.c_str();
    1364          48 :             papszArgs = CSLSetNameValue(papszArgs, pszKey, pszValue);
    1365             :         }
    1366             : 
    1367         104 :         eErr = (poPixelFunc->first)(
    1368             :             static_cast<void **>(pBuffers), nBufferCount, pData, nBufXSize,
    1369             :             nBufYSize, eSrcType, eBufType, static_cast<int>(nPixelSpace),
    1370             :             static_cast<int>(nLineSpace), papszArgs);
    1371             : 
    1372         104 :         CSLDestroy(papszArgs);
    1373             :     }
    1374           0 : end:
    1375             :     // Release buffers.
    1376         662 :     for (int iBuffer = 0; iBuffer < nBufferCount; iBuffer++)
    1377             :     {
    1378         173 :         VSIFree(pBuffers[iBuffer]);
    1379             :     }
    1380         489 :     CPLFree(pBuffers);
    1381             : 
    1382         489 :     return eErr;
    1383             : }
    1384             : 
    1385             : /************************************************************************/
    1386             : /*                         IGetDataCoverageStatus()                     */
    1387             : /************************************************************************/
    1388             : 
    1389           1 : int VRTDerivedRasterBand::IGetDataCoverageStatus(
    1390             :     int /* nXOff */, int /* nYOff */, int /* nXSize */, int /* nYSize */,
    1391             :     int /* nMaskFlagStop */, double *pdfDataPct)
    1392             : {
    1393           1 :     if (pdfDataPct != nullptr)
    1394           0 :         *pdfDataPct = -1.0;
    1395             :     return GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED |
    1396           1 :            GDAL_DATA_COVERAGE_STATUS_DATA;
    1397             : }
    1398             : 
    1399             : /************************************************************************/
    1400             : /*                              XMLInit()                               */
    1401             : /************************************************************************/
    1402             : 
    1403         163 : CPLErr VRTDerivedRasterBand::XMLInit(const CPLXMLNode *psTree,
    1404             :                                      const char *pszVRTPath,
    1405             :                                      VRTMapSharedResources &oMapSharedSources)
    1406             : 
    1407             : {
    1408             :     const CPLErr eErr =
    1409         163 :         VRTSourcedRasterBand::XMLInit(psTree, pszVRTPath, oMapSharedSources);
    1410         163 :     if (eErr != CE_None)
    1411           0 :         return eErr;
    1412             : 
    1413             :     // Read derived pixel function type.
    1414         163 :     SetPixelFunctionName(CPLGetXMLValue(psTree, "PixelFunctionType", nullptr));
    1415         163 :     if (pszFuncName == nullptr || EQUAL(pszFuncName, ""))
    1416             :     {
    1417           1 :         CPLError(CE_Failure, CPLE_AppDefined, "PixelFunctionType missing");
    1418           1 :         return CE_Failure;
    1419             :     }
    1420             : 
    1421         162 :     m_poPrivate->m_osLanguage =
    1422         162 :         CPLGetXMLValue(psTree, "PixelFunctionLanguage", "C");
    1423         229 :     if (!EQUAL(m_poPrivate->m_osLanguage, "C") &&
    1424          67 :         !EQUAL(m_poPrivate->m_osLanguage, "Python"))
    1425             :     {
    1426           1 :         CPLError(CE_Failure, CPLE_NotSupported,
    1427             :                  "Unsupported PixelFunctionLanguage");
    1428           1 :         return CE_Failure;
    1429             :     }
    1430             : 
    1431         161 :     m_poPrivate->m_osCode = CPLGetXMLValue(psTree, "PixelFunctionCode", "");
    1432         198 :     if (!m_poPrivate->m_osCode.empty() &&
    1433          37 :         !EQUAL(m_poPrivate->m_osLanguage, "Python"))
    1434             :     {
    1435           1 :         CPLError(CE_Failure, CPLE_NotSupported,
    1436             :                  "PixelFunctionCode can only be used with Python");
    1437           1 :         return CE_Failure;
    1438             :     }
    1439             : 
    1440         160 :     m_poPrivate->m_nBufferRadius =
    1441         160 :         atoi(CPLGetXMLValue(psTree, "BufferRadius", "0"));
    1442         160 :     if (m_poPrivate->m_nBufferRadius < 0 || m_poPrivate->m_nBufferRadius > 1024)
    1443             :     {
    1444           1 :         CPLError(CE_Failure, CPLE_AppDefined, "Invalid value for BufferRadius");
    1445           1 :         return CE_Failure;
    1446             :     }
    1447         170 :     if (m_poPrivate->m_nBufferRadius != 0 &&
    1448          11 :         !EQUAL(m_poPrivate->m_osLanguage, "Python"))
    1449             :     {
    1450           1 :         CPLError(CE_Failure, CPLE_NotSupported,
    1451             :                  "BufferRadius can only be used with Python");
    1452           1 :         return CE_Failure;
    1453             :     }
    1454             : 
    1455             :     const CPLXMLNode *const psArgs =
    1456         158 :         CPLGetXMLNode(psTree, "PixelFunctionArguments");
    1457         158 :     if (psArgs != nullptr)
    1458             :     {
    1459          90 :         for (const CPLXMLNode *psIter = psArgs->psChild; psIter;
    1460          58 :              psIter = psIter->psNext)
    1461             :         {
    1462          58 :             if (psIter->eType == CXT_Attribute)
    1463             :             {
    1464          58 :                 m_poPrivate->m_oFunctionArgs.push_back(
    1465          58 :                     std::pair<CPLString, CPLString>(psIter->pszValue,
    1466          58 :                                                     psIter->psChild->pszValue));
    1467             :             }
    1468             :         }
    1469             :     }
    1470             : 
    1471             :     // Read optional source transfer data type.
    1472             :     const char *pszTypeName =
    1473         158 :         CPLGetXMLValue(psTree, "SourceTransferType", nullptr);
    1474         158 :     if (pszTypeName != nullptr)
    1475             :     {
    1476          74 :         eSourceTransferType = GDALGetDataTypeByName(pszTypeName);
    1477             :     }
    1478             : 
    1479             :     // Whether to skip non contributing sources
    1480             :     const char *pszSkipNonContributiongSources =
    1481         158 :         CPLGetXMLValue(psTree, "SkipNonContributingSources", nullptr);
    1482         158 :     if (pszSkipNonContributiongSources)
    1483             :     {
    1484           2 :         m_poPrivate->m_bSkipNonContributingSourcesSpecified = true;
    1485           4 :         m_poPrivate->m_bSkipNonContributingSources =
    1486           2 :             CPLTestBool(pszSkipNonContributiongSources);
    1487             :     }
    1488             : 
    1489         158 :     return CE_None;
    1490             : }
    1491             : 
    1492             : /************************************************************************/
    1493             : /*                           SerializeToXML()                           */
    1494             : /************************************************************************/
    1495             : 
    1496           7 : CPLXMLNode *VRTDerivedRasterBand::SerializeToXML(const char *pszVRTPath,
    1497             :                                                  bool &bHasWarnedAboutRAMUsage,
    1498             :                                                  size_t &nAccRAMUsage)
    1499             : {
    1500           7 :     CPLXMLNode *psTree = VRTSourcedRasterBand::SerializeToXML(
    1501             :         pszVRTPath, bHasWarnedAboutRAMUsage, nAccRAMUsage);
    1502             : 
    1503             :     /* -------------------------------------------------------------------- */
    1504             :     /*      Set subclass.                                                   */
    1505             :     /* -------------------------------------------------------------------- */
    1506           7 :     CPLCreateXMLNode(CPLCreateXMLNode(psTree, CXT_Attribute, "subClass"),
    1507             :                      CXT_Text, "VRTDerivedRasterBand");
    1508             : 
    1509             :     /* ---- Encode DerivedBand-specific fields ---- */
    1510           7 :     if (!EQUAL(m_poPrivate->m_osLanguage, "C"))
    1511             :     {
    1512           5 :         CPLSetXMLValue(psTree, "PixelFunctionLanguage",
    1513           5 :                        m_poPrivate->m_osLanguage);
    1514             :     }
    1515           7 :     if (pszFuncName != nullptr && strlen(pszFuncName) > 0)
    1516           6 :         CPLSetXMLValue(psTree, "PixelFunctionType", pszFuncName);
    1517           7 :     if (!m_poPrivate->m_oFunctionArgs.empty())
    1518             :     {
    1519             :         CPLXMLNode *psArgs =
    1520           1 :             CPLCreateXMLNode(psTree, CXT_Element, "PixelFunctionArguments");
    1521           3 :         for (size_t i = 0; i < m_poPrivate->m_oFunctionArgs.size(); ++i)
    1522             :         {
    1523           2 :             const char *pszKey = m_poPrivate->m_oFunctionArgs[i].first.c_str();
    1524             :             const char *pszValue =
    1525           2 :                 m_poPrivate->m_oFunctionArgs[i].second.c_str();
    1526           2 :             CPLCreateXMLNode(CPLCreateXMLNode(psArgs, CXT_Attribute, pszKey),
    1527             :                              CXT_Text, pszValue);
    1528             :         }
    1529             :     }
    1530           7 :     if (!m_poPrivate->m_osCode.empty())
    1531             :     {
    1532           4 :         if (m_poPrivate->m_osCode.find("<![CDATA[") == std::string::npos)
    1533             :         {
    1534           4 :             CPLCreateXMLNode(
    1535             :                 CPLCreateXMLNode(psTree, CXT_Element, "PixelFunctionCode"),
    1536             :                 CXT_Literal,
    1537           8 :                 ("<![CDATA[" + m_poPrivate->m_osCode + "]]>").c_str());
    1538             :         }
    1539             :         else
    1540             :         {
    1541           0 :             CPLSetXMLValue(psTree, "PixelFunctionCode", m_poPrivate->m_osCode);
    1542             :         }
    1543             :     }
    1544           7 :     if (m_poPrivate->m_nBufferRadius != 0)
    1545           1 :         CPLSetXMLValue(psTree, "BufferRadius",
    1546           1 :                        CPLSPrintf("%d", m_poPrivate->m_nBufferRadius));
    1547           7 :     if (this->eSourceTransferType != GDT_Unknown)
    1548           2 :         CPLSetXMLValue(psTree, "SourceTransferType",
    1549             :                        GDALGetDataTypeName(eSourceTransferType));
    1550             : 
    1551           7 :     if (m_poPrivate->m_bSkipNonContributingSourcesSpecified)
    1552             :     {
    1553           1 :         CPLSetXMLValue(psTree, "SkipNonContributingSources",
    1554           1 :                        m_poPrivate->m_bSkipNonContributingSources ? "true"
    1555             :                                                                   : "false");
    1556             :     }
    1557             : 
    1558           7 :     return psTree;
    1559             : }
    1560             : 
    1561             : /************************************************************************/
    1562             : /*                             GetMinimum()                             */
    1563             : /************************************************************************/
    1564             : 
    1565           5 : double VRTDerivedRasterBand::GetMinimum(int *pbSuccess)
    1566             : {
    1567           5 :     return GDALRasterBand::GetMinimum(pbSuccess);
    1568             : }
    1569             : 
    1570             : /************************************************************************/
    1571             : /*                             GetMaximum()                             */
    1572             : /************************************************************************/
    1573             : 
    1574           5 : double VRTDerivedRasterBand::GetMaximum(int *pbSuccess)
    1575             : {
    1576           5 :     return GDALRasterBand::GetMaximum(pbSuccess);
    1577             : }
    1578             : 
    1579             : /************************************************************************/
    1580             : /*                       ComputeRasterMinMax()                          */
    1581             : /************************************************************************/
    1582             : 
    1583           1 : CPLErr VRTDerivedRasterBand::ComputeRasterMinMax(int bApproxOK,
    1584             :                                                  double *adfMinMax)
    1585             : {
    1586           1 :     return GDALRasterBand::ComputeRasterMinMax(bApproxOK, adfMinMax);
    1587             : }
    1588             : 
    1589             : /************************************************************************/
    1590             : /*                         ComputeStatistics()                          */
    1591             : /************************************************************************/
    1592             : 
    1593           1 : CPLErr VRTDerivedRasterBand::ComputeStatistics(int bApproxOK, double *pdfMin,
    1594             :                                                double *pdfMax, double *pdfMean,
    1595             :                                                double *pdfStdDev,
    1596             :                                                GDALProgressFunc pfnProgress,
    1597             :                                                void *pProgressData)
    1598             : 
    1599             : {
    1600           1 :     return GDALRasterBand::ComputeStatistics(bApproxOK, pdfMin, pdfMax, pdfMean,
    1601             :                                              pdfStdDev, pfnProgress,
    1602           1 :                                              pProgressData);
    1603             : }
    1604             : 
    1605             : /************************************************************************/
    1606             : /*                            GetHistogram()                            */
    1607             : /************************************************************************/
    1608             : 
    1609           1 : CPLErr VRTDerivedRasterBand::GetHistogram(double dfMin, double dfMax,
    1610             :                                           int nBuckets, GUIntBig *panHistogram,
    1611             :                                           int bIncludeOutOfRange, int bApproxOK,
    1612             :                                           GDALProgressFunc pfnProgress,
    1613             :                                           void *pProgressData)
    1614             : 
    1615             : {
    1616           1 :     return VRTRasterBand::GetHistogram(dfMin, dfMax, nBuckets, panHistogram,
    1617             :                                        bIncludeOutOfRange, bApproxOK,
    1618           1 :                                        pfnProgress, pProgressData);
    1619             : }
    1620             : 
    1621             : /*! @endcond */

Generated by: LCOV version 1.14