// stdafx.cpp : 只包括标准包含文件的源文件
// test.pch 将作为预编译头
// stdafx.obj 将包含预编译类型信息

#include "stdafx.h"


HMODULE g_hlzma = NULL;
lzma_compress g_PtrCompress = NULL;
lzma_uncompress g_PtrUnCompress = NULL;

BOOL LoadlzmaLibarary()
{
	if ( g_hlzma == NULL )
	{
		g_hlzma = (HMODULE)LoadLibrary(_T("Lzmalib.dll"));
		if (!g_hlzma)
			return FALSE;
	}

	g_PtrCompress = (lzma_compress)GetProcAddress(g_hlzma, "LzmaCompress");
	if ( !g_PtrCompress )
	{
		FreelzmaLibarary();
		return FALSE;
	}

	g_PtrUnCompress = (lzma_uncompress)GetProcAddress(g_hlzma, "LzmaUncompress");
	if ( !g_PtrUnCompress )
	{
		FreelzmaLibarary();
		return FALSE;
	}

	return TRUE;
}

void FreelzmaLibarary()
{
	if ( g_hlzma )
	{
		if ( FreeLibrary(g_hlzma) )
		{
			g_hlzma = NULL;
			g_PtrCompress = NULL;
			g_PtrUnCompress = NULL;
		}
	}
}


const TCHAR g_szLzma[] = _T("#LZMA#");

BOOL CompressFile(CString strCompressFile)
{
	//////////////////////////////////////////////////////////////////////////
	// 压缩文件;
	//////////////////////////////////////////////////////////////////////////
	byte prop[5] = {0};  
	size_t nPropSize = 5;  

	ULONGLONG ulTickCount = GetTickCount64();
	CString strSaveFile = strCompressFile.Mid(0,strCompressFile.ReverseFind('.')) + ".lam";
	if ( PathFileExists(strSaveFile) )
	{
		// 已经压缩了;
		return TRUE;
	}

	FILE* fp = fopen(strCompressFile, "rb");  
	if ( NULL != fp )  
	{  
		fseek(fp, 0, SEEK_END);  
		size_t nSrcLen = ftell(fp);  
		fseek(fp, 0, SEEK_SET);  
		byte* pSrcData = (byte*)malloc(nSrcLen);  
		fread(pSrcData, nSrcLen, 1, fp);  
		fclose(fp);  
		size_t nDesLen = nSrcLen;  
		byte* pDesData = (byte*)malloc(nDesLen);  
#ifdef USE_LIB
		int nRet = LzmaCompress(pDesData, &nDesLen, pSrcData, nSrcLen, prop, &nPropSize, 9, (1<<24), 8, 0, 2, 32, 2);  
#else
		int nRet = LzmaCompress(pDesData, &nDesLen, pSrcData, nSrcLen, prop, &nPropSize, 9, (1<<24), 3, 0, 2, 32, 2);  
#endif
		if ( SZ_ERROR_OUTPUT_EOF == nRet )  
		{//申请内存不足; 
			free(pDesData);  
			nDesLen += nSrcLen;  
			pDesData = (byte*)malloc(nDesLen);  
#ifdef USE_LIB
			nRet = LzmaCompress(pDesData, &nDesLen, pSrcData, nSrcLen, prop, &nPropSize, 5, (1<<24), 8, 0, 2, 32, 2); 
#else
			nRet = LzmaCompress(pDesData, &nDesLen, pSrcData, nSrcLen, prop, &nPropSize, 9, (1<<24), 3, 0, 2, 32, 2);  
#endif
		}  

		if ( SZ_OK == nRet )  
		{//压缩完成,保存文件;  
			fp = fopen(strSaveFile, "wb+");  
			if ( NULL != fp )  
			{  			
				// 写入压缩标记;
				fwrite(g_szLzma, strlen(g_szLzma), 1, fp);
				// 写入prop;
				fwrite(prop, 5, 1, fp);
				// 写入nPropSize;
				fwrite(&nPropSize, sizeof(size_t), 1, fp);
				// 写入文件大小;
				fwrite(&nSrcLen, sizeof(size_t), 1, fp);
				// 写入压缩数据;
				fwrite(pDesData, nDesLen, 1, fp);  

				fclose(fp);  
			}  
			else
			{
				nRet = SZ_ERROR_FAIL;
			}
		}  

		free(pDesData);  
		free(pSrcData);  

		if ( nRet != SZ_OK )
			return FALSE;
	} 
	else
	{
		return FALSE;
	}

	return TRUE;
}