CMake/Source/cmGeneratedFileStream.h

120 lines
3.7 KiB
C++

/*=========================================================================
Program: CMake - Cross-Platform Makefile Generator
Module: $RCSfile$
Language: C++
Date: $Date$
Version: $Revision$
Copyright (c) 2002 Kitware, Inc., Insight Consortium. All rights reserved.
See Copyright.txt or http://www.cmake.org/HTML/Copyright.html for details.
This software is distributed WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the above copyright notices for more information.
=========================================================================*/
#ifndef cmGeneratedFileStream_h
#define cmGeneratedFileStream_h
#include "cmStandardIncludes.h"
// This is the first base class of cmGeneratedFileStream. It will be
// created before and destroyed after the ofstream portion and can
// therefore be used to manage the temporary file.
class cmGeneratedFileStreamBase
{
protected:
// This constructor does not prepare the temporary file. The open
// method must be used.
cmGeneratedFileStreamBase();
// This constructor prepares the temporary output file.
cmGeneratedFileStreamBase(const char* name);
// The destructor renames the temporary output file to the real name.
~cmGeneratedFileStreamBase();
// Internal method to setup the instance for a given file name.
void Open(const char* name);
// Internal file replacement implementation.
int RenameFile(const char* oldname, const char* newname);
// Internal file compression implementation.
int CompressFile(const char* oldname, const char* newname);
// The name of the final destination file for the output.
std::string m_Name;
// The name of the temporary file.
std::string m_TempName;
// Whether to do a copy-if-different.
bool m_CopyIfDifferent;
// Whether the destination file should be replaced.
bool m_Okay;
// Whether the destionation file is compressed
bool m_Compress;
};
/** \class cmGeneratedFileStream
* \brief Output stream for generated files.
*
* File generation should be atomic so that if CMake is killed then a
* generated file is either the original version or the complete new
* version. This stream is used to make sure file generation is
* atomic. Optionally the output file is only replaced if its
* contents have changed to prevent the file modification time from
* being updated.
*/
class cmGeneratedFileStream: private cmGeneratedFileStreamBase,
public std::ofstream
{
public:
typedef std::ofstream Stream;
/**
* This constructor prepares a default stream. The open method must
* be used before writing to the stream.
*/
cmGeneratedFileStream();
/**
* This constructor takes the name of the file to be generated. It
* automatically generates a name for the temporary file. If the
* file cannot be opened an error message is produced unless the
* second argument is set to true.
*/
cmGeneratedFileStream(const char* name, bool quiet=false);
/**
* The destructor checks the stream status to be sure the temporary
* file was successfully written before allowing the original to be
* replaced.
*/
~cmGeneratedFileStream();
/**
* Open an output file by name. This should be used only with a
* default-constructed stream. It automatically generates a name
* for the temporary file. If the file cannot be opened an error
* message is produced unless the second argument is set to true.
*/
cmGeneratedFileStream& Open(const char* name, bool quiet=false);
/**
* Set whether copy-if-different is done.
*/
void SetCopyIfDifferent(bool copy_if_different);
/**
* Set whether compression is done.
*/
void SetCompression(bool compression);
};
#endif