cpl_vsil_curl_class.h

/******************************************************************************
 *
 * Project:  CPL - Common Portability Library
 * Purpose:  Declarations for /vsicurl/ and related file systems
 * Author:   Even Rouault, even.rouault at spatialys.com
 *
 ******************************************************************************
 * Copyright (c) 2010-2018, Even Rouault <even.rouault at spatialys.com>
 *
 * SPDX-License-Identifier: MIT
 ****************************************************************************/
 
#ifndef CPL_VSIL_CURL_CLASS_H_INCLUDED
#define CPL_VSIL_CURL_CLASS_H_INCLUDED
 
#ifdef HAVE_CURL
 
#include "cpl_aws.h"
#include "cpl_azure.h"
#include "cpl_port.h"
#include "cpl_json.h"
#include "cpl_http.h"
#include "cpl_string.h"
#include "cpl_vsil_curl_priv.h"
#include "cpl_mem_cache.h"
#include "cpl_multiproc.h"
 
#include "cpl_curl_priv.h"
 
#include <algorithm>
#include <atomic>
#include <condition_variable>
#include <set>
#include <map>
#include <memory>
#include <mutex>
#include <thread>
#include <utility>
 
// To avoid aliasing to CopyFile to CopyFileA on Windows
#ifdef CopyFile
#undef CopyFile
#endif

 
// Leave it for backward compatibility, but deprecate.
#define HAVE_CURLINFO_REDIRECT_URL
 
void VSICurlStreamingClearCache(void);  // from cpl_vsil_curl_streaming.cpp
 
struct curl_slist *VSICurlSetOptions(CURL *hCurlHandle, const char *pszURL,
                                     const char *const *papszOptions);
 
struct curl_slist *VSICurlSetContentTypeFromExt(struct curl_slist *polist,
                                                const char *pszPath);
 
struct curl_slist *VSICurlSetCreationHeadersFromOptions(
    struct curl_slist *headers, CSLConstList papszOptions, const char *pszPath);
 
namespace cpl
{
 
typedef enum
{
    EXIST_UNKNOWN = -1,
    EXIST_NO,
    EXIST_YES,
} ExistStatus;
 
class FileProp
{
  public:
    unsigned int nGenerationAuthParameters = 0;
    ExistStatus eExists = EXIST_UNKNOWN;
    int nHTTPCode = 0;
    vsi_l_offset fileSize = 0;
    time_t mTime = 0;
    time_t nExpireTimestampLocal = 0;
    std::string osRedirectURL{};
    bool bHasComputedFileSize = false;
    bool bIsDirectory = false;
    bool bIsAzureFolder = false;
    int nMode = 0;  // st_mode member of struct stat
    bool bS3LikeRedirect = false;
    std::string ETag{};
};
 
struct CachedDirList
{
    bool bGotFileList = false;
    unsigned int nGenerationAuthParameters = 0;
    CPLStringList oFileList{}; /* only file name without path */
};
 
struct WriteFuncStruct
{
    char *pBuffer = nullptr;
    size_t nSize = 0;
    bool bIsHTTP = false;
    bool bMultiRange = false;
    vsi_l_offset nStartOffset = 0;
    vsi_l_offset nEndOffset = 0;
    int nHTTPCode = 0;       // potentially after redirect
    int nFirstHTTPCode = 0;  // the one of the redirect
    vsi_l_offset nContentLength = 0;
    bool bFoundContentRange = false;
    bool bError = false;
    bool bInterruptDownload = false;
    bool bDetectRangeDownloadingError = false;
    GIntBig nTimestampDate = 0;  // Corresponds to Date: header field
 
    VSILFILE *fp = nullptr;
    VSICurlReadCbkFunc pfnReadCbk = nullptr;
    void *pReadCbkUserData = nullptr;
    bool bInterrupted = false;
};
 
struct PutData
{
    const GByte *pabyData = nullptr;
    size_t nOff = 0;
    size_t nTotalSize = 0;
 
    static size_t ReadCallBackBuffer(char *buffer, size_t size, size_t nitems,
                                     void *instream)
    {
        PutData *poThis = static_cast<PutData *>(instream);
        const size_t nSizeMax = size * nitems;
        const size_t nSizeToWrite =
            std::min(nSizeMax, poThis->nTotalSize - poThis->nOff);
        memcpy(buffer, poThis->pabyData + poThis->nOff, nSizeToWrite);
        poThis->nOff += nSizeToWrite;
        return nSizeToWrite;
    }
};
 
/************************************************************************/
/*                     VSICurlFilesystemHandler                         */
/************************************************************************/
 
class VSICurlHandle;
 
class VSICurlFilesystemHandlerBase : public VSIFilesystemHandler
{
    CPL_DISALLOW_COPY_ASSIGN(VSICurlFilesystemHandlerBase)
 
    struct FilenameOffsetPair
    {
        std::string filename_;
        vsi_l_offset offset_;
 
        FilenameOffsetPair(const std::string &filename, vsi_l_offset offset)
            : filename_(filename), offset_(offset)
        {
        }
 
        bool operator==(const FilenameOffsetPair &other) const
        {
            return filename_ == other.filename_ && offset_ == other.offset_;
        }
    };
 
    struct FilenameOffsetPairHasher
    {
        std::size_t operator()(const FilenameOffsetPair &k) const
        {
            return std::hash<std::string>()(k.filename_) ^
                   std::hash<vsi_l_offset>()(k.offset_);
        }
    };
 
    using RegionCacheType = lru11::Cache<
        FilenameOffsetPair, std::shared_ptr<std::string>, lru11::NullLock,
        std::unordered_map<
            FilenameOffsetPair,
            typename std::list<lru11::KeyValuePair<
                FilenameOffsetPair, std::shared_ptr<std::string>>>::iterator,
            FilenameOffsetPairHasher>>;
 
    std::unique_ptr<RegionCacheType>
        m_poRegionCacheDoNotUseDirectly{};  // do not access directly. Use
                                            // GetRegionCache();
    RegionCacheType *GetRegionCache();
 
    // LRU cache that just keeps in memory if this file system handler is
    // spposed to know the file properties of a file. The actual cache is a
    // shared one among all network file systems.
    // The aim of that design is that invalidating /vsis3/foo results in
    // /vsis3_streaming/foo to be invalidated as well.
    lru11::Cache<std::string, bool> oCacheFileProp;
 
    int nCachedFilesInDirList = 0;
    lru11::Cache<std::string, CachedDirList> oCacheDirList;
 
    char **ParseHTMLFileList(const char *pszFilename, int nMaxFiles,
                             char *pszData, bool *pbGotFileList);
 
    // Data structure and map to store regions that are in progress, to
    // avoid simultaneous downloads of the same region in different threads
    // Cf https://github.com/OSGeo/gdal/issues/8041
    struct RegionInDownload
    {
        std::mutex oMutex{};
        std::condition_variable oCond{};
        bool bDownloadInProgress = false;
        int nWaiters = 0;
        std::string osData{};
    };
 
    std::mutex m_oMutex{};
    std::map<std::string, std::unique_ptr<RegionInDownload>>
        m_oMapRegionInDownload{};
 
  protected:
    CPLMutex *hMutex = nullptr;
 
    virtual VSICurlHandle *CreateFileHandle(const char *pszFilename);
    virtual char **GetFileList(const char *pszFilename, int nMaxFiles,
                               bool *pbGotFileList);
 
    void RegisterEmptyDir(const std::string &osDirname);
 
    bool
    AnalyseS3FileList(const std::string &osBaseURL, const char *pszXML,
                      CPLStringList &osFileList, int nMaxFiles,
                      const std::set<std::string> &oSetIgnoredStorageClasses,
                      bool &bIsTruncated);
 
    void AnalyseSwiftFileList(const std::string &osBaseURL,
                              const std::string &osPrefix, const char *pszJson,
                              CPLStringList &osFileList, int nMaxFilesThisQuery,
                              int nMaxFiles, bool &bIsTruncated,
                              std::string &osNextMarker);
 
    static const char *GetOptionsStatic();
 
    VSICurlFilesystemHandlerBase();
 
  public:
    ~VSICurlFilesystemHandlerBase() override;
 
    static bool IsAllowedFilename(const char *pszFilename);
 
    VSIVirtualHandleUniquePtr Open(const char *pszFilename,
                                   const char *pszAccess, bool bSetError,
                                   CSLConstList /* papszOptions */) override;
 
    int Stat(const char *pszFilename, VSIStatBufL *pStatBuf,
             int nFlags) override;
    char **ReadDirEx(const char *pszDirname, int nMaxFiles) override;
    char **SiblingFiles(const char *pszFilename) override;
 
    int HasOptimizedReadMultiRange(const char * /* pszPath */) override
    {
        return true;
    }
 
    const char *GetActualURL(const char *pszFilename) override;
 
    const char *GetOptions() override;
 
    char **GetFileMetadata(const char *pszFilename, const char *pszDomain,
                           CSLConstList papszOptions) override;
 
    char **ReadDirInternal(const char *pszDirname, int nMaxFiles,
                           bool *pbGotFileList);
    void InvalidateDirContent(const std::string &osDirname);
 
    virtual const char *GetDebugKey() const = 0;
 
    virtual std::string GetFSPrefix() const = 0;
    virtual bool AllowCachedDataFor(const char *pszFilename);
 
    bool IsLocal(const char * /* pszPath */) const override
    {
        return false;
    }
 
    virtual bool
    SupportsSequentialWrite(const char * /* pszPath */,
                            bool /* bAllowLocalTempFile */) override
    {
        return false;
    }
 
    virtual bool SupportsRandomWrite(const char * /* pszPath */,
                                     bool /* bAllowLocalTempFile */) override
    {
        return false;
    }
 
    std::shared_ptr<std::string> GetRegion(const char *pszURL,
                                           vsi_l_offset nFileOffsetStart);
 
    void AddRegion(const char *pszURL, vsi_l_offset nFileOffsetStart,
                   size_t nSize, const char *pData);
 
    std::pair<bool, std::string>
    NotifyStartDownloadRegion(const std::string &osURL,
                              vsi_l_offset startOffset, int nBlocks);
    void NotifyStopDownloadRegion(const std::string &osURL,
                                  vsi_l_offset startOffset, int nBlocks,
                                  const std::string &osData);
 
    bool GetCachedFileProp(const char *pszURL, FileProp &oFileProp);
    void SetCachedFileProp(const char *pszURL, FileProp &oFileProp);
    void InvalidateCachedData(const char *pszURL);
 
    CURLM *GetCurlMultiHandleFor(const std::string &osURL);
 
    virtual void ClearCache();
    virtual void PartialClearCache(const char *pszFilename);
 
    bool GetCachedDirList(const char *pszURL, CachedDirList &oCachedDirList);
    void SetCachedDirList(const char *pszURL, CachedDirList &oCachedDirList);
    bool ExistsInCacheDirList(const std::string &osDirname, bool *pbIsDir);
 
    virtual std::string GetURLFromFilename(const std::string &osFilename) const;
 
    std::string
    GetStreamingFilename(const std::string &osFilename) const override = 0;
 
    static std::set<std::string> GetS3IgnoredStorageClasses();
};
 
class VSICurlFilesystemHandler final : public VSICurlFilesystemHandlerBase
{
    CPL_DISALLOW_COPY_ASSIGN(VSICurlFilesystemHandler)
 
  public:
    VSICurlFilesystemHandler() = default;
 
    const char *GetDebugKey() const override
    {
        return "VSICURL";
    }
 
    std::string GetFSPrefix() const override
    {
        return "/vsicurl/";
    }
 
    std::string
    GetStreamingFilename(const std::string &osFilename) const override;
};
 
/************************************************************************/
/*                           VSICurlHandle                              */
/************************************************************************/
 
class VSICurlHandle /* non final*/ : public VSIVirtualHandle
{
    CPL_DISALLOW_COPY_ASSIGN(VSICurlHandle)
 
  protected:
    VSICurlFilesystemHandlerBase *poFS = nullptr;
 
    bool m_bCached = true;
 
    mutable FileProp oFileProp{};
 
    mutable std::mutex m_oMutex{};
    std::string m_osFilename{};  // e.g "/vsicurl/http://example.com/foo"
    char *m_pszURL = nullptr;    // e.g "http://example.com/foo"
    mutable std::string m_osQueryString{};  // e.g. an Azure SAS
 
    CPLStringList m_aosHTTPOptions{};
    CPLHTTPRetryParameters
        m_oRetryParameters;  // must be initialized in constructor
 
    vsi_l_offset lastDownloadedOffset = VSI_L_OFFSET_MAX;
    int nBlocksToDownload = 1;
 
    bool bStopOnInterruptUntilUninstall = false;
    bool bInterrupted = false;
    VSICurlReadCbkFunc pfnReadCbk = nullptr;
    void *pReadCbkUserData = nullptr;
 
    CPLStringList m_aosHeaders{};
 
    void DownloadRegionPostProcess(const vsi_l_offset startOffset,
                                   const int nBlocks, const char *pBuffer,
                                   size_t nSize);
 
  private:
    vsi_l_offset curOffset = 0;
 
    bool bEOF = false;
    bool bError = false;
 
    virtual std::string DownloadRegion(vsi_l_offset startOffset, int nBlocks);
 
    bool m_bUseHead = false;
    bool m_bUseRedirectURLIfNoQueryStringParams = false;
 
    mutable std::atomic<bool> m_bInterrupt = false;
 
    // Specific to Planetary Computer signing:
    // https://planetarycomputer.microsoft.com/docs/concepts/sas/
    mutable bool m_bPlanetaryComputerURLSigning = false;
    mutable std::string m_osPlanetaryComputerCollection{};
    void ManagePlanetaryComputerSigning() const;
 
    void UpdateQueryString() const;
 
    int ReadMultiRangeSingleGet(int nRanges, void **ppData,
                                const vsi_l_offset *panOffsets,
                                const size_t *panSizes);
    std::string GetRedirectURLIfValid(bool &bHasExpired,
                                      CPLStringList &aosHTTPOptions) const;
 
    void UpdateRedirectInfo(CURL *hCurlHandle,
                            const WriteFuncStruct &sWriteFuncHeaderData);
 
    // Used by AdviseRead()
    struct AdviseReadRange
    {
        bool bDone = false;
        bool bToRetry = true;
        double dfSleepDelay = 0.0;
        std::mutex oMutex{};
        std::condition_variable oCV{};
        vsi_l_offset nStartOffset = 0;
        size_t nSize = 0;
        std::vector<GByte> abyData{};
        CPLHTTPRetryContext retryContext;
 
        explicit AdviseReadRange(const CPLHTTPRetryParameters &oRetryParameters)
            : retryContext(oRetryParameters)
        {
        }
 
        AdviseReadRange(const AdviseReadRange &) = delete;
        AdviseReadRange &operator=(const AdviseReadRange &) = delete;
        AdviseReadRange(AdviseReadRange &&) = delete;
        AdviseReadRange &operator=(AdviseReadRange &&) = delete;
    };
 
    std::vector<std::unique_ptr<AdviseReadRange>> m_aoAdviseReadRanges{};
    std::thread m_oThreadAdviseRead{};
    CURLM *m_hCurlMultiHandleForAdviseRead = nullptr;
 
  protected:
    virtual struct curl_slist *GetCurlHeaders(const std::string & /*osVerb*/,
                                              struct curl_slist *psHeaders)
    {
        return psHeaders;
    }
 
    virtual bool AllowAutomaticRedirection()
    {
        return true;
    }
 
    virtual bool CanRestartOnError(const char *, const char *, bool)
    {
        return false;
    }
 
    virtual bool UseLimitRangeGetInsteadOfHead()
    {
        return false;
    }
 
    virtual bool IsDirectoryFromExists(const char * /*pszVerb*/,
                                       int /*response_code*/)
    {
        return false;
    }
 
    virtual void ProcessGetFileSizeResult(const char * /* pszContent */)
    {
    }
 
    void SetURL(const char *pszURL);
 
    virtual bool Authenticate(const char * /* pszFilename */)
    {
        return false;
    }
 
  public:
    VSICurlHandle(VSICurlFilesystemHandlerBase *poFS, const char *pszFilename,
                  const char *pszURLIn = nullptr);
    ~VSICurlHandle() override;
 
    int Seek(vsi_l_offset nOffset, int nWhence) override;
    vsi_l_offset Tell() override;
    size_t Read(void *pBuffer, size_t nSize, size_t nMemb) override;
    int ReadMultiRange(int nRanges, void **ppData,
                       const vsi_l_offset *panOffsets,
                       const size_t *panSizes) override;
    size_t Write(const void *pBuffer, size_t nSize, size_t nMemb) override;
    void ClearErr() override;
    int Eof() override;
    int Error() override;
    int Flush() override;
    int Close() override;
 
    void Interrupt() override
    {
        m_bInterrupt = true;
    }
 
    bool HasPRead() const override
    {
        return true;
    }
 
    size_t PRead(void *pBuffer, size_t nSize,
                 vsi_l_offset nOffset) const override;
 
    void AdviseRead(int nRanges, const vsi_l_offset *panOffsets,
                    const size_t *panSizes) override;
 
    size_t GetAdviseReadTotalBytesLimit() const override;
 
    bool IsKnownFileSize() const
    {
        return oFileProp.bHasComputedFileSize;
    }
 
    vsi_l_offset GetFileSizeOrHeaders(bool bSetError, bool bGetHeaders);
 
    virtual vsi_l_offset GetFileSize(bool bSetError)
    {
        return GetFileSizeOrHeaders(bSetError, false);
    }
 
    bool Exists(bool bSetError);
 
    bool IsDirectory() const
    {
        return oFileProp.bIsDirectory;
    }
 
    int GetMode() const
    {
        return oFileProp.nMode;
    }
 
    time_t GetMTime() const
    {
        return oFileProp.mTime;
    }
 
    const CPLStringList &GetHeaders()
    {
        return m_aosHeaders;
    }
 
    int InstallReadCbk(VSICurlReadCbkFunc pfnReadCbk, void *pfnUserData,
                       int bStopOnInterruptUntilUninstall);
    int UninstallReadCbk();
 
    const char *GetURL() const
    {
        return m_pszURL;
    }

    void SetCache(bool bCache)
    {
        m_bCached = bCache;
    }
};
 
/************************************************************************/
/*                  VSICurlFilesystemHandlerBaseWritable                */
/************************************************************************/
 
class VSICurlFilesystemHandlerBaseWritable /* non final */
    : public VSICurlFilesystemHandlerBase
{
    CPL_DISALLOW_COPY_ASSIGN(VSICurlFilesystemHandlerBaseWritable)
 
  protected:
    VSICurlFilesystemHandlerBaseWritable() = default;
 
    virtual VSIVirtualHandleUniquePtr
    CreateWriteHandle(const char *pszFilename, CSLConstList papszOptions) = 0;
 
  public:
    VSIVirtualHandleUniquePtr Open(const char *pszFilename,
                                   const char *pszAccess, bool bSetError,
                                   CSLConstList /* papszOptions */) override;
 
    bool SupportsSequentialWrite(const char * /* pszPath */,
                                 bool /* bAllowLocalTempFile */) override
    {
        return true;
    }
 
    bool SupportsRandomWrite(const char * /* pszPath */,
                             bool /* bAllowLocalTempFile */) override;
};
 
/************************************************************************/
/*                        IVSIS3LikeFSHandler                           */
/************************************************************************/
 
class IVSIS3LikeFSHandler /* non final */
    : public VSICurlFilesystemHandlerBaseWritable
{
    CPL_DISALLOW_COPY_ASSIGN(IVSIS3LikeFSHandler)
 
    virtual int MkdirInternal(const char *pszDirname, long nMode,
                              bool bDoStatCheck);
 
  protected:
    char **GetFileList(const char *pszFilename, int nMaxFiles,
                       bool *pbGotFileList) override;
 
    virtual IVSIS3LikeHandleHelper *CreateHandleHelper(const char *pszURI,
                                                       bool bAllowNoObject) = 0;
 
    virtual int CopyObject(const char *oldpath, const char *newpath,
                           CSLConstList papszMetadata);
 
    int RmdirRecursiveInternal(const char *pszDirname, int nBatchSize);
 
    virtual bool
    IsAllowedHeaderForObjectCreation(const char * /* pszHeaderName */)
    {
        return false;
    }
 
    IVSIS3LikeFSHandler() = default;
 
  public:
    int Unlink(const char *pszFilename) override;
    int Mkdir(const char *pszDirname, long nMode) override;
    int Rmdir(const char *pszDirname) override;
    int Stat(const char *pszFilename, VSIStatBufL *pStatBuf,
             int nFlags) override;
    int Rename(const char *oldpath, const char *newpath, GDALProgressFunc,
               void *) override;
 
    virtual int CopyFile(const char *pszSource, const char *pszTarget,
                         VSILFILE *fpSource, vsi_l_offset nSourceSize,
                         const char *const *papszOptions,
                         GDALProgressFunc pProgressFunc,
                         void *pProgressData) override;
 
    virtual int DeleteObject(const char *pszFilename);
 
    virtual int *DeleteObjectBatch(CSLConstList papszFilesOrDirs);
 
    bool Sync(const char *pszSource, const char *pszTarget,
              const char *const *papszOptions, GDALProgressFunc pProgressFunc,
              void *pProgressData, char ***ppapszOutputs) override;
 
    VSIDIR *OpenDir(const char *pszPath, int nRecurseDepth,
                    const char *const *papszOptions) override;
};
 
/************************************************************************/
/*                 IVSIS3LikeFSHandlerWithMultipartUpload               */
/************************************************************************/
 
class IVSIS3LikeFSHandlerWithMultipartUpload /* non final */
    : public IVSIS3LikeFSHandler
{
    CPL_DISALLOW_COPY_ASSIGN(IVSIS3LikeFSHandlerWithMultipartUpload)
 
  protected:
    IVSIS3LikeFSHandlerWithMultipartUpload() = default;
 
  public:
    virtual bool SupportsNonSequentialMultipartUpload() const
    {
        return true;
    }
 
    virtual bool SupportsParallelMultipartUpload() const
    {
        return true;
    }
 
    virtual bool SupportsMultipartAbort() const = 0;
 
    size_t GetUploadChunkSizeInBytes(const char *pszFilename,
                                     const char *pszSpecifiedValInBytes);
 
    virtual int CopyFileRestartable(const char *pszSource,
                                    const char *pszTarget,
                                    const char *pszInputPayload,
                                    char **ppszOutputPayload,
                                    CSLConstList papszOptions,
                                    GDALProgressFunc pProgressFunc,
                                    void *pProgressData) override;

    // Limit currently used by S3 and GS.
    // Cf https://docs.aws.amazon.com/AmazonS3/latest/userguide/qfacts.html
    // and https://cloud.google.com/storage/quotas#requests
    virtual int GetMaximumPartCount()
    {
        return 10000;
    }

    // Limit currently used by S3 and GS.
    // Cf https://docs.aws.amazon.com/AmazonS3/latest/userguide/qfacts.html
    // and https://cloud.google.com/storage/quotas#requests
    virtual int GetMinimumPartSizeInMiB()
    {
        return 5;
    }

    // Limit currently used by S3 and GS.
    // Cf https://docs.aws.amazon.com/AmazonS3/latest/userguide/qfacts.html
    // and https://cloud.google.com/storage/quotas#requests
    virtual int GetMaximumPartSizeInMiB()
    {
#if SIZEOF_VOIDP == 8
        return 5 * 1024;
#else
        // Cannot be larger than 4, otherwise integer overflow would occur
        // 1 GiB is the maximum reasonable value on a 32-bit machine
        return 1 * 1024;
#endif
    }

    virtual int GetDefaultPartSizeInMiB()
    {
        return 50;
    }
 
    virtual std::string
    InitiateMultipartUpload(const std::string &osFilename,
                            IVSIS3LikeHandleHelper *poS3HandleHelper,
                            const CPLHTTPRetryParameters &oRetryParameters,
                            CSLConstList papszOptions);
 
    virtual std::string
    UploadPart(const std::string &osFilename, int nPartNumber,
               const std::string &osUploadID, vsi_l_offset nPosition,
               const void *pabyBuffer, size_t nBufferSize,
               IVSIS3LikeHandleHelper *poS3HandleHelper,
               const CPLHTTPRetryParameters &oRetryParameters,
               CSLConstList papszOptions);
 
    virtual bool CompleteMultipart(
        const std::string &osFilename, const std::string &osUploadID,
        const std::vector<std::string> &aosEtags, vsi_l_offset nTotalSize,
        IVSIS3LikeHandleHelper *poS3HandleHelper,
        const CPLHTTPRetryParameters &oRetryParameters);
 
    virtual bool AbortMultipart(const std::string &osFilename,
                                const std::string &osUploadID,
                                IVSIS3LikeHandleHelper *poS3HandleHelper,
                                const CPLHTTPRetryParameters &oRetryParameters);
 
    bool AbortPendingUploads(const char *pszFilename) override;
 
    bool MultipartUploadGetCapabilities(int *pbNonSequentialUploadSupported,
                                        int *pbParallelUploadSupported,
                                        int *pbAbortSupported,
                                        size_t *pnMinPartSize,
                                        size_t *pnMaxPartSize,
                                        int *pnMaxPartCount) override;
 
    char *MultipartUploadStart(const char *pszFilename,
                               CSLConstList papszOptions) override;
 
    char *MultipartUploadAddPart(const char *pszFilename,
                                 const char *pszUploadId, int nPartNumber,
                                 vsi_l_offset nFileOffset, const void *pData,
                                 size_t nDataLength,
                                 CSLConstList papszOptions) override;
 
    bool MultipartUploadEnd(const char *pszFilename, const char *pszUploadId,
                            size_t nPartIdsCount,
                            const char *const *apszPartIds,
                            vsi_l_offset nTotalSize,
                            CSLConstList papszOptions) override;
 
    bool MultipartUploadAbort(const char *pszFilename, const char *pszUploadId,
                              CSLConstList papszOptions) override;
};
 
/************************************************************************/
/*                          IVSIS3LikeHandle                            */
/************************************************************************/
 
class IVSIS3LikeHandle /* non final */ : public VSICurlHandle
{
    CPL_DISALLOW_COPY_ASSIGN(IVSIS3LikeHandle)
 
  protected:
    bool UseLimitRangeGetInsteadOfHead() override
    {
        return true;
    }
 
    bool IsDirectoryFromExists(const char *pszVerb, int response_code) override
    {
        // A bit dirty, but on S3, a GET on a existing directory returns a 416
        return response_code == 416 && EQUAL(pszVerb, "GET") &&
               std::string(m_pszURL).back() == '/';
    }
 
    void ProcessGetFileSizeResult(const char *pszContent) override
    {
        oFileProp.bIsDirectory =
            strstr(pszContent, "ListBucketResult") != nullptr;
    }
 
  public:
    IVSIS3LikeHandle(VSICurlFilesystemHandlerBase *poFSIn,
                     const char *pszFilename, const char *pszURLIn)
        : VSICurlHandle(poFSIn, pszFilename, pszURLIn)
    {
    }
 
    ~IVSIS3LikeHandle() override;
};
 
/************************************************************************/
/*                       VSIMultipartWriteHandle                        */
/************************************************************************/
 
class VSIMultipartWriteHandle final : public VSIVirtualHandle
{
    CPL_DISALLOW_COPY_ASSIGN(VSIMultipartWriteHandle)
 
    IVSIS3LikeFSHandlerWithMultipartUpload *m_poFS = nullptr;
    std::string m_osFilename{};
    IVSIS3LikeHandleHelper *m_poS3HandleHelper = nullptr;
    CPLStringList m_aosOptions{};
    CPLStringList m_aosHTTPOptions{};
    CPLHTTPRetryParameters m_oRetryParameters;
 
    vsi_l_offset m_nCurOffset = 0;
    size_t m_nBufferOff = 0;
    size_t m_nBufferSize = 0;
    bool m_bClosed = false;
    GByte *m_pabyBuffer = nullptr;
    std::string m_osUploadID{};
    int m_nPartNumber = 0;
    std::vector<std::string> m_aosEtags{};
    bool m_bError = false;
 
    WriteFuncStruct m_sWriteFuncHeaderData{};
 
    bool UploadPart();
    bool DoSinglePartPUT();
 
    void InvalidateParentDirectory();
 
  public:
    VSIMultipartWriteHandle(IVSIS3LikeFSHandlerWithMultipartUpload *poFS,
                            const char *pszFilename,
                            IVSIS3LikeHandleHelper *poS3HandleHelper,
                            CSLConstList papszOptions);
    ~VSIMultipartWriteHandle() override;
 
    int Seek(vsi_l_offset nOffset, int nWhence) override;
    vsi_l_offset Tell() override;
    size_t Read(void *pBuffer, size_t nSize, size_t nMemb) override;
    size_t Write(const void *pBuffer, size_t nSize, size_t nMemb) override;
 
    void ClearErr() override
    {
    }
 
    int Error() override
    {
        return FALSE;
    }
 
    int Eof() override
    {
        return FALSE;
    }
 
    int Close() override;
 
    bool IsOK()
    {
        return m_pabyBuffer != nullptr;
    }
};
 
/************************************************************************/
/*                         VSIChunkedWriteHandle()                      */
/************************************************************************/

class VSIChunkedWriteHandle final : public VSIVirtualHandle
{
    CPL_DISALLOW_COPY_ASSIGN(VSIChunkedWriteHandle)
 
    IVSIS3LikeFSHandler *m_poFS = nullptr;
    std::string m_osFilename{};
    IVSIS3LikeHandleHelper *m_poS3HandleHelper = nullptr;
    CPLStringList m_aosOptions{};
    CPLStringList m_aosHTTPOptions{};
    CPLHTTPRetryParameters m_oRetryParameters;
 
    vsi_l_offset m_nCurOffset = 0;
    size_t m_nBufferOff = 0;
    bool m_bError = false;
    bool m_bClosed = false;
 
    CURLM *m_hCurlMulti = nullptr;
    CURL *m_hCurl = nullptr;
    const void *m_pBuffer = nullptr;
    std::string m_osCurlErrBuf{};
    size_t m_nChunkedBufferOff = 0;
    size_t m_nChunkedBufferSize = 0;
    size_t m_nWrittenInPUT = 0;
 
    WriteFuncStruct m_sWriteFuncHeaderData{};
 
    static size_t ReadCallBackBufferChunked(char *buffer, size_t size,
                                            size_t nitems, void *instream);
    int FinishChunkedTransfer();
 
    bool DoEmptyPUT();
 
    void InvalidateParentDirectory();
 
  public:
    VSIChunkedWriteHandle(IVSIS3LikeFSHandler *poFS, const char *pszFilename,
                          IVSIS3LikeHandleHelper *poS3HandleHelper,
                          CSLConstList papszOptions);
    ~VSIChunkedWriteHandle() override;
 
    int Seek(vsi_l_offset nOffset, int nWhence) override;
    vsi_l_offset Tell() override;
    size_t Read(void *pBuffer, size_t nSize, size_t nMemb) override;
    size_t Write(const void *pBuffer, size_t nSize, size_t nMemb) override;
 
    void ClearErr() override
    {
    }
 
    int Error() override
    {
        return FALSE;
    }
 
    int Eof() override
    {
        return FALSE;
    }
 
    int Close() override;
};
 
/************************************************************************/
/*                        VSIAppendWriteHandle                          */
/************************************************************************/
 
class VSIAppendWriteHandle CPL_NON_FINAL : public VSIVirtualHandle
{
    CPL_DISALLOW_COPY_ASSIGN(VSIAppendWriteHandle)
 
  protected:
    VSICurlFilesystemHandlerBase *m_poFS = nullptr;
    std::string m_osFSPrefix{};
    std::string m_osFilename{};
    CPLHTTPRetryParameters m_oRetryParameters{};
 
    vsi_l_offset m_nCurOffset = 0;
    int m_nBufferOff = 0;
    int m_nBufferSize = 0;
    int m_nBufferOffReadCallback = 0;
    bool m_bClosed = false;
    GByte *m_pabyBuffer = nullptr;
    bool m_bError = false;
 
    static size_t ReadCallBackBuffer(char *buffer, size_t size, size_t nitems,
                                     void *instream);
    virtual bool Send(bool bIsLastBlock) = 0;
 
  public:
    VSIAppendWriteHandle(VSICurlFilesystemHandlerBase *poFS,
                         const char *pszFSPrefix, const char *pszFilename,
                         int nChunkSize);
    ~VSIAppendWriteHandle() override;
 
    int Seek(vsi_l_offset nOffset, int nWhence) override;
    vsi_l_offset Tell() override;
    size_t Read(void *pBuffer, size_t nSize, size_t nMemb) override;
    size_t Write(const void *pBuffer, size_t nSize, size_t nMemb) override;
 
    void ClearErr() override
    {
    }
 
    int Error() override
    {
        return FALSE;
    }
 
    int Eof() override
    {
        return FALSE;
    }
 
    int Close() override;
 
    bool IsOK()
    {
        return m_pabyBuffer != nullptr;
    }
};
 
/************************************************************************/
/*                     VSIDIRWithMissingDirSynthesis                    */
/************************************************************************/
 
struct VSIDIRWithMissingDirSynthesis /* non final */ : public VSIDIR
{
    std::vector<std::unique_ptr<VSIDIREntry>> aoEntries{};
 
  protected:
    ~VSIDIRWithMissingDirSynthesis() override;
 
    std::vector<std::string> m_aosSubpathsStack{};
 
    void SynthetizeMissingDirectories(const std::string &osCurSubdir,
                                      bool bAddEntryForThisSubdir);
};
 
/************************************************************************/
/*                          VSIDIRS3Like                                */
/************************************************************************/
 
struct VSIDIRS3Like /* non final */ : public VSIDIRWithMissingDirSynthesis
{
    const std::string m_osDirName;
 
    int nRecurseDepth = 0;
 
    std::string osNextMarker{};
    int nPos = 0;
 
    std::string osBucket{};
    std::string osObjectKey{};
    VSICurlFilesystemHandlerBase *poFS = nullptr;
    IVSIS3LikeFSHandler *poS3FS = nullptr;
    std::unique_ptr<IVSIS3LikeHandleHelper> poHandleHelper{};
    int nMaxFiles = 0;
    bool bCacheEntries = true;
    bool m_bSynthetizeMissingDirectories = false;
    std::string m_osFilterPrefix{};
 
    // used when listing only the file system prefix
    std::unique_ptr<VSIDIR, decltype(&VSICloseDir)> m_subdir{nullptr,
                                                             VSICloseDir};
 
    VSIDIRS3Like(const std::string &osDirName, IVSIS3LikeFSHandler *poFSIn)
        : m_osDirName(osDirName), poFS(poFSIn), poS3FS(poFSIn)
    {
    }
 
    VSIDIRS3Like(const std::string &osDirName,
                 VSICurlFilesystemHandlerBase *poFSIn)
        : m_osDirName(osDirName), poFS(poFSIn)
    {
    }
 
    VSIDIRS3Like(const VSIDIRS3Like &) = delete;
    VSIDIRS3Like &operator=(const VSIDIRS3Like &) = delete;
 
    const VSIDIREntry *NextDirEntry() override;
 
    virtual bool IssueListDir() = 0;
    void clear();
};
 
/************************************************************************/
/*                         CurlRequestHelper                            */
/************************************************************************/
 
struct CurlRequestHelper
{
    WriteFuncStruct sWriteFuncData{};
    WriteFuncStruct sWriteFuncHeaderData{};
    char szCurlErrBuf[CURL_ERROR_SIZE + 1] = {};
 
    CurlRequestHelper();
    ~CurlRequestHelper();
    long perform(CURL *hCurlHandle,
                 struct curl_slist *headers,  // ownership transferred
                 VSICurlFilesystemHandlerBase *poFS,
                 IVSIS3LikeHandleHelper *poS3HandleHelper);
};
 
/************************************************************************/
/*                       NetworkStatisticsLogger                        */
/************************************************************************/
 
class NetworkStatisticsLogger
{
    static int gnEnabled;
    static NetworkStatisticsLogger gInstance;
 
    NetworkStatisticsLogger() = default;
 
    std::mutex m_mutex{};
 
    struct Counters
    {
        GIntBig nHEAD = 0;
        GIntBig nGET = 0;
        GIntBig nPUT = 0;
        GIntBig nPOST = 0;
        GIntBig nDELETE = 0;
        GIntBig nGETDownloadedBytes = 0;
        GIntBig nPUTUploadedBytes = 0;
        GIntBig nPOSTDownloadedBytes = 0;
        GIntBig nPOSTUploadedBytes = 0;
    };
 
    enum class ContextPathType
    {
        FILESYSTEM,
        FILE,
        ACTION,
    };
 
    struct ContextPathItem
    {
        ContextPathType eType;
        std::string osName;
 
        ContextPathItem(ContextPathType eTypeIn, const std::string &osNameIn)
            : eType(eTypeIn), osName(osNameIn)
        {
        }
 
        bool operator<(const ContextPathItem &other) const
        {
            if (static_cast<int>(eType) < static_cast<int>(other.eType))
                return true;
            if (static_cast<int>(eType) > static_cast<int>(other.eType))
                return false;
            return osName < other.osName;
        }
    };
 
    struct Stats
    {
        Counters counters{};
        std::map<ContextPathItem, Stats> children{};
 
        void AsJSON(CPLJSONObject &oJSON) const;
    };
 
    // Workaround bug in Coverity Scan
    // coverity[generated_default_constructor_used_in_field_initializer]
    Stats m_stats{};
    std::map<GIntBig, std::vector<ContextPathItem>>
        m_mapThreadIdToContextPath{};
 
    static void ReadEnabled();
 
    std::vector<Counters *> GetCountersForContext();
 
  public:
    static inline bool IsEnabled()
    {
        if (gnEnabled < 0)
        {
            ReadEnabled();
        }
        return gnEnabled == TRUE;
    }
 
    static void EnterFileSystem(const char *pszName);
 
    static void LeaveFileSystem();
 
    static void EnterFile(const char *pszName);
 
    static void LeaveFile();
 
    static void EnterAction(const char *pszName);
 
    static void LeaveAction();
 
    static void LogHEAD();
 
    static void LogGET(size_t nDownloadedBytes);
 
    static void LogPUT(size_t nUploadedBytes);
 
    static void LogPOST(size_t nUploadedBytes, size_t nDownloadedBytes);
 
    static void LogDELETE();
 
    static void Reset();
 
    static std::string GetReportAsSerializedJSON();
};
 
struct NetworkStatisticsFileSystem
{
    inline explicit NetworkStatisticsFileSystem(const char *pszName)
    {
        NetworkStatisticsLogger::EnterFileSystem(pszName);
    }
 
    inline ~NetworkStatisticsFileSystem()
    {
        NetworkStatisticsLogger::LeaveFileSystem();
    }
};
 
struct NetworkStatisticsFile
{
    inline explicit NetworkStatisticsFile(const char *pszName)
    {
        NetworkStatisticsLogger::EnterFile(pszName);
    }
 
    inline ~NetworkStatisticsFile()
    {
        NetworkStatisticsLogger::LeaveFile();
    }
};
 
struct NetworkStatisticsAction
{
    inline explicit NetworkStatisticsAction(const char *pszName)
    {
        NetworkStatisticsLogger::EnterAction(pszName);
    }
 
    inline ~NetworkStatisticsAction()
    {
        NetworkStatisticsLogger::LeaveAction();
    }
};
 
}  // namespace cpl
 
int VSICURLGetDownloadChunkSize();
 
void VSICURLInitWriteFuncStruct(cpl::WriteFuncStruct *psStruct, VSILFILE *fp,
                                VSICurlReadCbkFunc pfnReadCbk,
                                void *pReadCbkUserData);
size_t VSICurlHandleWriteFunc(void *buffer, size_t count, size_t nmemb,
                              void *req);
void VSICURLMultiPerform(CURLM *hCurlMultiHandle, CURL *hEasyHandle = nullptr,
                         std::atomic<bool> *pbInterrupt = nullptr);
void VSICURLResetHeaderAndWriterFunctions(CURL *hCurlHandle);
 
int VSICurlParseUnixPermissions(const char *pszPermissions);
 
// Cache of file properties (size, etc.)
bool VSICURLGetCachedFileProp(const char *pszURL, cpl::FileProp &oFileProp);
void VSICURLSetCachedFileProp(const char *pszURL, cpl::FileProp &oFileProp);
void VSICURLInvalidateCachedFileProp(const char *pszURL);
void VSICURLInvalidateCachedFilePropPrefix(const char *pszURL);
void VSICURLDestroyCacheFileProp();
 
void VSICURLMultiCleanup(CURLM *hCurlMultiHandle);

 
#endif  // HAVE_CURL
 
#endif  // CPL_VSIL_CURL_CLASS_H_INCLUDED