zipcentraldir.h

ZIP压缩代码：基于开源ZipArchive和zlib

////////////////////////////////////////////////////////////////////////////////
// $Workfile: ZipCentralDir.h $
// $Archive: /ZipArchive/ZipCentralDir.h $
// $Date: 02-03-31 16:59 $ $Author: Tadeusz Dracz $
////////////////////////////////////////////////////////////////////////////////
// This source file is part of the ZipArchive library source distribution and
// is Copyright 2000-2003 by Tadeusz Dracz (http://www.artpol-software.com/)
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
// 
// For the licensing details see the file License.txt
////////////////////////////////////////////////////////////////////////////////

/**
* \file ZipCentralDir.h
*	Interface for the CZipCentralDir class.
*
*/

#if !defined(AFX_CENTRALDIR_H__859029E8_8927_4717_9D4B_E26E5DA12BAE__INCLUDED_)
#define AFX_CENTRALDIR_H__859029E8_8927_4717_9D4B_E26E5DA12BAE__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000

#if (_MSC_VER > 1000) && (defined ZIP_HAS_DLL)
	#pragma warning( disable : 4251 ) // needs to have dll-interface to be used by clients of class
#endif

#include "ZipException.h"
#include "ZipFileHeader.h"
#include "ZipAutoBuffer.h"
#include "ZipCollections.h"
#include "ZipCompatibility.h"
#include "ZipExport.h"
#define ZIPARCHIVE_DATADESCRIPTOR_LEN 12

/**
	A class representing the central directory record in the archive.
*/
class ZIP_API CZipCentralDir  
{
	/**
		Used in fast finding files by the filename.
		A structure for the internal use only.
		\see CZipCentralDir::m_findarray
		\see CZipArchive::GetFindFastElement
		\see CZipArchive::FindFile
		\see CZipArchive::EnableFindFast
	*/
	struct ZIP_API CZipFindFast
	{
		CZipFindFast()
		{
			m_uIndex = 0;
			m_pHeader= NULL;
		}
		CZipFindFast(CZipFileHeader* pHeader, WORD uIndex):m_pHeader(pHeader), m_uIndex(uIndex){}
		/**
			A pointer to the structure in CZipCentralDir. We extract a name from it.
		*/
		CZipFileHeader* m_pHeader;

		/**
			The index in the central directory of the \e m_pHeader.
		*/
		WORD m_uIndex;
	};
	
public:
	/**
		Stores general information about the central directory record.
	*/
	struct ZIP_API Info
	{
		DWORD m_uCentrDirPos;	///< the position of the beginning of the central directory (as located by #Locate)
		DWORD m_uBytesBeforeZip;///< The number of bytes before the actual zip archive in a file. It is non-zero for self-extracting archives.
		WORD m_uThisDisk;		///< number of the disk with the central directory end record (the number of disks in the disk-spanning archive)
		WORD m_uDiskWithCD;		///< number of the disk with the start of the central directory
		WORD m_uDiskEntriesNo;	///< total number of entries in the central dir on this disk
		WORD m_uEntriesNumber;	///< total number of entries in the central dir
		DWORD m_uSize;			///< size of the central directory (valid only if #m_bOnDisk is \c true; use #GetSize instead)
		DWORD m_uOffset;		///< offset of start of central directory with respect to the starting disk number 
								///< (as written in the central directory record);
								///< valid only if #m_bOnDisk is \c true
		bool m_bOnDisk;			///< \c true if the central directory is physically present in the archive

	protected:
		friend CZipCentralDir;
		bool CheckIfOK_1()
		{
			return ((DWORD)m_uCentrDirPos >= m_uOffset + m_uSize);
		}
		void SetBytesBeforeZip(bool bIsSpan)
		{
			m_uBytesBeforeZip = bIsSpan ? 0 : m_uCentrDirPos - m_uSize - m_uOffset;
		}
		bool CheckIfOK_2()
		{
			return (m_uSize || !m_uEntriesNumber) && (m_uEntriesNumber || !m_uSize);
		}
		void DiskChange(int iCurrentDisk)
		{
			m_uThisDisk = (WORD)iCurrentDisk;
			if (m_uEntriesNumber)
			{
				m_uDiskEntriesNo = 0;	
			}
			else
			{
				m_uDiskWithCD = m_uThisDisk;
				m_uOffset = 0;
			}
		}
	};

	CZipCentralDir();
	virtual ~CZipCentralDir();

	static char m_gszSignature[]; ///< central dir signature

	char m_szSignature[4];	///< end of central dir signature (must be 0x06054b50)

	CZipAutoBuffer m_pszComment;	///< the archive comment
	CZipAutoBuffer m_pLocalExtraField; ///< a local extra field
	CZipFileHeader* m_pOpenedFile;	///< points to a currently opened file or NULL if no file is opened

	/**
		Called by CZipArchive::OpenInternal.
	*/
	void Init();

	/**
		Read the central directory from the archive.
		\note Throws exceptions.
	*/
	void Read();

	/**
		Open the file.
		\param uIndex
			zero-based index of the file to open
		\note Throws exceptions.
	*/
	void OpenFile(WORD uIndex);

/**	
	Test if the given file header index is valid.
	\param	uIndex
		a zero-based index 
	\return	\c true if the file with the given index exists inside the archive; otherwise \c false;
*/
	bool IsValidIndex(int uIndex)const;

/**
	Remove the file header from the central directory.
	\param	pHeader
		the header to remove
	\param iIndex if index is not known set it to -1
	\param bShift 
	\note Throws exceptions.
*/
	void RemoveFile(CZipFileHeader* pHeader, int iIndex = -1, bool bShift = true);


    /**
       Remove last file from the central directory.
       
     */
	void RemoveLastFile(CZipFileHeader* pHeader = NULL, int iIndex = -1)
	{
		if (iIndex == -1)
		{
			iIndex = m_headers.GetSize() - 1;
			if (iIndex == -1)
				return;
		}
		if (!pHeader)
			pHeader = m_headers[iIndex];
		DWORD uNewSize = pHeader->m_uOffset + GetBytesBefore();
		// then remove
		RemoveFile(pHeader, iIndex);

		m_pStorage->Flush();
		m_pStorage->m_pFile->SetLength(uNewSize);
		m_info.m_bOnDisk = false; // it is true when AutoFlush is set to true
	}


	/**
		Remove all files
		\note Throws exceptions.
	*/
	void RemoveAll();
/**
	Cleanup the structure.
	\param	bEverything
		- \c true - clear some attributes and remove all the file headers from memory
		- \c false - do not remove the file headers. It is called in that manner
		from CZipArchive::CloseFileAfterTestFailed so that the 
		next file can be tested for the integrity
	\see CZipArchive::CloseFileAfterTestFailed
*/
	void Clear(bool bEverything = true);

/**
	Add a new file to the central directory.
	\param	header
		copy data from it to the new file header	
	\param iReplaceIndex if different from -1, the index of the file to be replaced
	\return the pointer to the new header
	\note Throws exceptions.
*/
	CZipFileHeader* AddNewFile(const CZipFileHeader & header, int iReplaceIndex = -1);

	/**
		return the header filename, converted if needed
	*/
	CZipString GetProperHeaderFileName(const CZipFileHeader* pHeader) const
	{
		if (!m_bConvertAfterOpen)
		{
			CZipFileHeader fh = *pHeader;
			ConvertFileName(true, false, &fh);
			return fh.GetFileName();
		}
		else
			return pHeader->GetFileName();
	}

/**
	Remove physically the central directory from the archive.
	Called during adding or deleting files.
	\note Throws exceptions.
*/
	void RemoveFromDisk();

/**
	Get the central directory size.
	\param	bWhole
		if \c true, include the size of the file headers
	\return	the size of the central directory
	\see CZipArchive::GetCentralDirSize
*/
	DWORD GetSize(bool bWhole = false) const;

	/**
		Close a file inside archive opened for reading.
		\param bAfterException \c true if closing after exception
		\note Throws exceptions.
	*/
	void CloseFile(bool bAfterException = false);

	/**
		Close a file inside archive opened for reading.
		\note Throws exceptions.
	*/
	void CloseNewFile();

	/**
		Write the central directory to the archive.
		\note Throws exceptions.
	*/
	void Write(CZipActionCallback* pCallback);
	
	/**
		\see CZipArchive::EnableFindFast
	*/
	void EnableFindFast(bool bEnable, bool bCaseSensitive);

	/**
		\see CZipArchive::FindFile