text: // Copyright 2014 PDFium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
   
  // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
  
  #ifndef _FX_STREAM_H_
  #define _FX_STREAM_H_
  #ifndef _FX_MEMORY_H_
  #include "fx_memory.h"
  #endif
  void* FX_OpenFolder(FX_LPCSTR path);
  void* FX_OpenFolder(FX_LPCWSTR path);
  FX_BOOL FX_GetNextFile(void* handle, CFX_ByteString& filename, FX_BOOL& bFolder);
  FX_BOOL FX_GetNextFile(void* handle, CFX_WideString& filename, FX_BOOL& bFolder);
  void FX_CloseFolder(void* handle);
  FX_WCHAR FX_GetFolderSeparator();
  FX_DEFINEHANDLE(FX_HFILE)
  #if _FXM_PLATFORM_ == _FXM_PLATFORM_WINDOWS_
  #define FX_FILESIZE			FX_INT32
  #else
  #include <fcntl.h>
  #include <unistd.h>
  #include <sys/stat.h>
  #ifndef O_BINARY
  #define O_BINARY 		0
  #endif
  #ifndef O_LARGEFILE
  #define O_LARGEFILE		0
  #endif
  #define FX_FILESIZE			off_t
  #endif
  #define FX_GETBYTEOFFSET32(a)	0
  #define FX_GETBYTEOFFSET40(a)	0
  #define FX_GETBYTEOFFSET48(a)	0
  #define FX_GETBYTEOFFSET56(a)	0
  #define FX_GETBYTEOFFSET24(a)  ((FX_BYTE)(a>>24))
  #define FX_GETBYTEOFFSET16(a)  ((FX_BYTE)(a>>16))
  #define FX_GETBYTEOFFSET8(a)   ((FX_BYTE)(a>>8))
  #define FX_GETBYTEOFFSET0(a)   ((FX_BYTE)(a))
  #define FX_FILEMODE_Write		0
  #define FX_FILEMODE_ReadOnly	1
  #define FX_FILEMODE_Truncate	2
  FX_HFILE	FX_File_Open(FX_BSTR fileName, FX_DWORD dwMode, IFX_Allocator* pAllocator = NULL);
  FX_HFILE	FX_File_Open(FX_WSTR fileName, FX_DWORD dwMode, IFX_Allocator* pAllocator = NULL);
  void		FX_File_Close(FX_HFILE hFile, IFX_Allocator* pAllocator = NULL);
  FX_FILESIZE	FX_File_GetSize(FX_HFILE hFile);
  FX_FILESIZE	FX_File_GetPosition(FX_HFILE hFile);
  FX_FILESIZE	FX_File_SetPosition(FX_HFILE hFile, FX_FILESIZE pos);
  size_t		FX_File_Read(FX_HFILE hFile, void* pBuffer, size_t szBuffer);
  size_t		FX_File_ReadPos(FX_HFILE hFile, void* pBuffer, size_t szBuffer, FX_FILESIZE pos);
  size_t		FX_File_Write(FX_HFILE hFile, const void* pBuffer, size_t szBuffer);
  size_t		FX_File_WritePos(FX_HFILE hFile, const void* pBuffer, size_t szBuffer, FX_FILESIZE pos);
  FX_BOOL		FX_File_Flush(FX_HFILE hFile);
  FX_BOOL		FX_File_Truncate(FX_HFILE hFile, FX_FILESIZE szFile);
  FX_BOOL		FX_File_Exist(FX_BSTR fileName);
  FX_BOOL		FX_File_Exist(FX_WSTR fileName);
  FX_BOOL		FX_File_Delete(FX_BSTR fileName);
  FX_BOOL		FX_File_Delete(FX_WSTR fileName);
  FX_BOOL		FX_File_Copy(FX_BSTR fileNameSrc, FX_BSTR fileNameDst);
  FX_BOOL		FX_File_Copy(FX_WSTR fileNameSrc, FX_WSTR fileNameDst);
  FX_BOOL		FX_File_Move(FX_BSTR fileNameSrc, FX_BSTR fileNameDst);
  FX_BOOL		FX_File_Move(FX_WSTR fileNameSrc, FX_WSTR fileNameDst);
  class IFX_StreamWrite
  {
  public:
  
      virtual void		Release() = 0;
  
      virtual	FX_BOOL		WriteBlock(const void* pData, size_t size) = 0;
  };
  class IFX_FileWrite : public IFX_StreamWrite
  {
  public:
  
      virtual void			Release() = 0;
  
      virtual FX_FILESIZE		GetSize() = 0;
  
      virtual FX_BOOL			Flush() = 0;
  
      virtual	FX_BOOL			WriteBlock(const void* pData, FX_FILESIZE offset, size_t size) = 0;
      virtual	FX_BOOL			WriteBlock(const void* pData, size_t size)
      {
          return WriteBlock(pData, GetSize(), size);
      }
  };
  IFX_FileWrite* FX_CreateFileWrite(FX_LPCSTR filename, IFX_Allocator* pAllocator = NULL);
  IFX_FileWrite* FX_CreateFileWrite(FX_LPCWSTR filename, IFX_Allocator* pAllocator = NULL);
  class IFX_StreamRead
  {
  public:
  
      virtual void			Release() = 0;
  
      virtual FX_BOOL			IsEOF() = 0;
  
      virtual FX_FILESIZE		GetPosition() = 0;
  
      virtual size_t			ReadBlock(void* buffer, size_t size) = 0;
  };
  class IFX_FileRead : IFX_StreamRead
  {
  public:
  
      virtual void			Release() = 0;
  
      virtual FX_FILESIZE		GetSize() = 0;
  
      virtual FX_BOOL			IsEOF()
      {
          return FALSE;
      }
  
      virtual FX_FILESIZE		GetPosition()
      {
          return 0;
      }
  
      virtual FX_BOOL			SetRange(FX_FILESIZE offset, FX_FILESIZE size)
      {
          return FALSE;
      }
  
      virtual void			ClearRange() {}
  
      virtual FX_BOOL			ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) = 0;
  
      virtual size_t			ReadBlock(void* buffer, size_t size)
      {
          return 0;
      }
  };
  IFX_FileRead* FX_CreateFileRead(FX_LPCSTR filename, IFX_Allocator* pAllocator = NULL);
  IFX_FileRead* FX_CreateFileRead(FX_LPCWSTR filename, IFX_Allocator* pAllocator = NULL);
  class IFX_FileStream : public IFX_FileRead, public IFX_FileWrite
  {
  public:
  
      virtual IFX_FileStream*		Retain() = 0;
  
      virtual void				Release() = 0;
  
      virtual FX_FILESIZE			GetSize() = 0;
  
      virtual FX_BOOL				IsEOF() = 0;
  
      virtual FX_FILESIZE			GetPosition() = 0;
  
      virtual FX_BOOL				ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) = 0;
  
      virtual size_t				ReadBlock(void* buffer, size_t size) = 0;
  
      virtual	FX_BOOL				WriteBlock(const void* buffer, FX_FILESIZE offset, size_t size) = 0;
      virtual	FX_BOOL				WriteBlock(const void* buffer, size_t size)
      {
          return WriteBlock(buffer, GetSize(), size);
      }
  
      virtual FX_BOOL				Flush() = 0;
  };
  IFX_FileStream*		FX_CreateFileStream(FX_LPCSTR filename, FX_DWORD dwModes, IFX_Allocator* pAllocator = NULL);
  IFX_FileStream*		FX_CreateFileStream(FX_LPCWSTR filename, FX_DWORD dwModes, IFX_Allocator* pAllocator = NULL);
  class IFX_MemoryStream : public IFX_FileStream
  {
  public:
  
      virtual FX_BOOL			IsConsecutive() const = 0;
  
      virtual void			EstimateSize(size_t nInitSize, size_t nGrowSize) = 0;
  
      virtual FX_LPBYTE		GetBuffer() const = 0;
  
      virtual void			AttachBuffer(FX_LPBYTE pBuffer, size_t nSize, FX_BOOL bTakeOver = FALSE) = 0;
  
      virtual void			DetachBuffer() = 0;
  };
  IFX_MemoryStream*	FX_CreateMemoryStream(FX_LPBYTE pBuffer, size_t nSize, FX_BOOL bTakeOver = FALSE, IFX_Allocator* pAllocator = NULL);
  IFX_MemoryStream*	FX_CreateMemoryStream(FX_BOOL bConsecutive = FALSE, IFX_Allocator* pAllocator = NULL);
  class IFX_BufferRead : public IFX_StreamRead
  {
  public:
  
      virtual void			Release() = 0;
  
      virtual FX_BOOL			IsEOF() = 0;
  
      virtual FX_FILESIZE		GetPosition() = 0;
  
      virtual size_t			ReadBlock(void* buffer, size_t size) = 0;
  
      virtual FX_BOOL			ReadNextBlock(FX_BOOL bRestart = FALSE) = 0;
  
      virtual FX_LPCBYTE		GetBlockBuffer() = 0;
  
      virtual size_t			GetBlockSize() = 0;
  
      virtual FX_FILESIZE		GetBlockOffset() = 0;
  };
  #endif
  