对比文件MD5差异并保存

标签：c++   md5   文件操作   

参考

http://www.cnblogs.com/flying_bat/archive/2007/09/25/905133.html

http://www.cnblogs.com/Sniper-quay/archive/2011/04/23/2025643.html

http://www.2cto.com/kf/201501/367905.html

http://blog.csdn.net/hqw7286/article/details/5603442

http://jingyan.baidu.com/article/48b558e35d29c47f38c09a1f.html

http://www.cnblogs.com/luxiaoxun/archive/2012/08/03/2621803.html

http://www.cnblogs.com/TianFang/archive/2006/12/30/607859.html

http://blog.csdn.net/debugconsole/article/details/8677313

http://www.oschina.net/question/117937_146959

http://www.cnblogs.com/02xiaoma/archive/2012/07/18/2597576.html

http://www.cnblogs.com/ggjucheng/archive/2012/01/03/2311241.html

http://bbs.csdn.net/topics/80303224

以上参考资料中有部分MD5库有错（本人的测试结果，可能测试过程错误。错误结果是不同的两个文件，产生的MD5值是一样的）

以下是代码，代码中的MD5库是正确的（同样也是本人的测试结果，只供参考）

环境：vs2013

入口文件main

// updator.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h" //一定放在第一位载入
#include<iostream>     
#include<string>     
#include<io.h>
#include "MD5Hash.h"
#include<stdio.h>
#include<fstream>
#include<map>
#include<sstream>

using namespace std;

//文件格式
struct updateRecord {
	string searchPath;//用于搜索和比较
	string filename;//文件名
	string md5str;//文件的md5码
};

//保存文本
map<string, updateRecord> *data_;
//对比时候使用
map<string, updateRecord> *dataNew_;
map<string, updateRecord> *dataOld_;

//获取MD5字符串
// void PrintMD5(const string &str, MD5 &md5) {
// 	cout << "MD5(\"" << str << "\") = " << md5.toString() << endl;
// }

//截取路径
string getNewPath(string str)
{
	int spos = (&str)->rfind("src/");
	if (spos < 1) {
		spos = (&str)->rfind("res/");
	}

	string newpath = "";
	if (spos > 0) {
		newpath = str.erase(0, spos);
	}

	return newpath;
}

//读取文件MD5值
void readMD5(string fname, string fpath)
{
// 	MD5 md5;
// 	md5.reset();
// 	md5.update(ifstream(fpath));
	//PrintMD5(fpath, md5);
	wstring md5wstr = CalcFileMD5(fpath);

	std::string md5str(md5wstr.length(), ' ');
	std::copy(md5wstr.begin(), md5wstr.end(), md5str.begin());

	updateRecord recod;
	recod.filename = fname;
	recod.md5str = md5str;
	recod.searchPath = getNewPath(fpath);
	data_->insert(make_pair(recod.searchPath, recod));
}

//扫描文件
void visit(string path, int layer)
{
	struct _finddata_t   filefind;
	//string  curr = path + "\\*.*";
	string  curr = path + "/*.*";
	int   done = 0, i, handle;
	if ((handle = _findfirst(curr.c_str(), &filefind)) == -1)return;
	while (!(done = _findnext(handle, &filefind)))
	{
		//printf("%s\n", filefind.name);
		if (!strcmp(filefind.name, "..") || !strcmp(filefind.name, ".") || !strcmp(filefind.name, ".svn")){
			continue;
		}
		for (i = 0; i < layer; i++)cout << "     ";
		if ((_A_SUBDIR == filefind.attrib)) //是目录  
		{
			printf("----------%s\n", filefind.name);
			//cout << filefind.name << "(dir)" << endl;
			curr = path + "/" + filefind.name;
			visit(curr, 1);
			continue;
		}
		else//不是目录，是文件       
		{
			string filepath = path + "/" + filefind.name;
			printf("\n========== %s", filepath.c_str());
			//cout << path + "\\" + filefind.name << endl;
			readMD5(filefind.name, filepath);
		}
	}
	printf("\n");
	_findclose(handle);
}

//保存日志
void saveTxt(string path, string name, map<string, updateRecord> *dmap)
{
	cout << "******** 打印保存文件 **********" << endl;
	//日志打开路径
	string fp = path + "/" + name;
	ofstream in;
	in.open(fp, ios::trunc);//打开该文件，没有则创建。并清空

	map<string, updateRecord>::iterator it = dmap->begin();
	for (it; it != dmap->end(); it++) {
		updateRecord m = it->second;
		//按照搜索路径，文件名，MD5码顺序保存
		in << m.searchPath << "\t" << m.filename << "\t" << m.md5str << "\t";
		cout << m.searchPath << "\t" << m.filename << "\t" << m.md5str << "\n" << endl;
	}

	in.close();
}

//功能1，保存文件MD5值
void function1()
{
	data_->clear();

	//扫描文件
	string path; // = "d:/server/k7android"
	cout << "请输入目录(符号/)" << endl;
	cin >> path;
	visit(path, 1);

	//保存日志
	string txtPath;
	cout << "请输入日志保存路径(符号/)" << endl;
	cin >> txtPath;
	string txtName;
	cout << "请输入日志名（**.txt）" << endl;
	cin >> txtName;
	saveTxt(txtPath, txtName, data_);
}
//---------------------------------------以上功能1----------------------------------------------------

//读取文件数据
//path日志打开路径
bool readTxt(map<string, updateRecord> *data, string path)
{
	char buffer[256];
	data->clear();
	fstream out;
	out.open(path, ios::in);
	if (!out) {
		cout << "打开文件：" << path << "  失败！！！" << endl;
		return false;
	}

	while (!out.eof()) {
		updateRecord recod;
		//按照搜索路径，文件名，MD5码顺序读取
		for (int i = 0; i < 3; i++) {
			if (!out.eof()) {
				out.getline(buffer, 10000, '\t');//getline(char *,int,char) 表示该行字符达到10000个或遇到tab就结束
				//cout << buffer << endl;
				/*if (i == 0) {
					//字串转数字
					int num;
					stringstream ss((string)buffer);
					ss >> num;
					cout << "num: " << num << endl;
					recod.num = num;
				}*/
				if (i == 0) {
					string searchPath = (string)buffer;
					cout << "searchPath: " << searchPath << endl;
					recod.searchPath = searchPath;
				}
				else if (i == 1) {
					string filename = (string)buffer;
					cout << "filename: " << filename << endl;
					recod.filename = filename;
				}
				else if (i == 2) {
					string md5str = (string)buffer;
					cout << "md5: " << md5str << endl;
					recod.md5str = md5str;
				}
			}
			else {
				switch (i)
				{
				//case 0: recod.num = 0; break;
				case 0: recod.searchPath = ""; break;
				case 1: recod.filename = ""; break;
				case 2: recod.md5str = ""; break;
				default:break;
				}
			}
		}//for

		data->insert(make_pair(recod.searchPath, recod));
	}

	return true;
}

//比较两个文件
void compareTxt(string newTxtName)
{
	map<string, updateRecord> *updateData = new map<string, updateRecord>();
	//拿新的和旧的比
	map<string, updateRecord>::iterator itNew = dataNew_->begin();
	//遍历新的文件
	for (itNew; itNew != dataNew_->end(); itNew++) {
		updateRecord rnew = itNew->second;
		string sp = rnew.searchPath;
		updateRecord rold;
		map<string, updateRecord>::iterator itOld = dataOld_->find(sp);
		//旧文件中有的，新文件没有的不需要查询
		if (itOld == dataOld_->end()) {
			//在旧文件中没找到，说明这个是新加文件。视为差异文件，需要被保存
			updateData->insert(make_pair(rnew.searchPath, rnew));
		}
		else {
			rold = itOld->second;
			if (rnew.md5str != rold.md5str) {
				//新文件的MD5值和旧文件的MD5值不同，说明被改动。视为差异文件，需要被保存
				updateData->insert(make_pair(rnew.searchPath, rnew));
			}
		}
	}

	//保存差异文件
	string savePath;
	cout << "输入差异文件列表保存路径（符号/）" << endl;
	cin >> savePath;
	string newName = "diff_" + newTxtName;
	saveTxt(savePath, newName, updateData);
}

//返回 1相同  2不同  3不能比较
int compare2(string pnew, string pold) 
{
	char buffernew[256];
	fstream outnew;
	outnew.open(pnew, ios::in);
	if (!outnew) {
		cout << "打开新文件：" << pnew << "  失败！！！" << endl;
		return 3;
	}

	char bufferold[256];
	fstream outold;
	outold.open(pold, ios::in);
	if (!outold) {
		cout << "打开旧文件：" << pold << "  失败！！！" << endl;
		return 2;
	}

	while (!outnew.eof()) {
		outnew.getline(buffernew, 10000, '\n');
		if (!outold.eof()) {
			outold.getline(bufferold, 10000, '\n');
			if ((string)buffernew != (string)bufferold) {
				return 2;
			}
		}
		else {
			//不同
			return 2;
		}
	}

	return 1;
}

void visit2(string pathnew, string pathold)
{
	int layerNew = 1;
	struct _finddata_t   filefind;
	//string  curr = path + "\\*.*";
	string  curr = pathnew + "/*.*";
	int   done = 0, i, handle;
	if ((handle = _findfirst(curr.c_str(), &filefind)) == -1)return;
	while (!(done = _findnext(handle, &filefind)))
	{
		//printf("%s\n", filefind.name);
		if (!strcmp(filefind.name, "..") || !strcmp(filefind.name, ".") || !strcmp(filefind.name, ".svn")){
			continue;
		}
		for (i = 0; i < layerNew; i++)cout << "     ";
		if ((_A_SUBDIR == filefind.attrib)) //是目录  
		{
			printf("----------%s\n", filefind.name);
			//cout << filefind.name << "(dir)" << endl;
			curr = pathnew + "/" + filefind.name;
			visit2(curr, pathold);
			continue;
		}
		else//不是目录，是文件       
		{
			string curr = pathnew + "/" + filefind.name;
			string fileNewPath = curr;
			//oldpath
			int spos = (&curr)->rfind("src/");
			if (spos < 1) {
				spos = (&curr)->rfind("res/");
			}

			string newpath = "";
			if (spos > 0) {
				newpath = curr.erase(0, spos);
			}
			string fileOldPath = pathold + "/" + newpath;
			
			printf("\n newpath========== %s", fileNewPath.c_str());
			printf("\n oldpath========== %s", fileOldPath.c_str());
			//cout << path + "\\" + filefind.name << endl;
			//readMD5(filefind.name, filepath);

			int ret = compare2(fileNewPath, fileOldPath);
			//1相同  2不同  3不能比较
			if (ret == 1) {
				cout << "文件相同：" << filefind.name << endl;
			}
			else if (ret == 2) {
				cout << "文件不同：" << filefind.name << endl;
			}
			else if (ret == 3) {
				cout << "两个文件不能比较！！！" << endl;
			}
			else {
				cout << "对比出错啦！！！" << endl;
			}
		}
	}
	printf("\n");
	_findclose(handle);
}

//功能2，对比MD5文件
void function2()
{
	string fn1;
	cout << "输入较新文件的名字（*.txt）" << endl;
	cin >> fn1;
	string fp1;
	cout << "输入较新文件的路径（符号/）" << endl;
	cin >> fp1;

	string fn2;
	cout << "输入较旧文件的名字（*.txt）" << endl;
	cin >> fn2;
	string fp2;
	cout << "输入较旧文件的路径（符号/）" << endl;
	cin >> fp2;

	//读取文件数据
	string f1 = fp1 + "/" + fn1;
	string f2 = fp2 + "/" + fn2;
	bool openSuccess = true;
	openSuccess = readTxt(dataNew_, f1);
	if (openSuccess)
		openSuccess = readTxt(dataOld_, f2);

	//对比文件数据，获取差异文件
	if (openSuccess)
		compareTxt(fn1);

	//全文件对比
	//visit2(fp1, fp2);
}

//功能选择
int chooseFunc()
{
	string func;
	cout << "选择功能：1读取并保存文件MD5；2对比两个文件差异；3结束" << endl;
	cin >> func;
	int funcn;
	stringstream ss(func);
	ss >> funcn;

	return funcn;
}

//入口
int _tmain(int argc, _TCHAR* argv[])
{
	printf("\n hello!!!\n");

	//定义数据表
	data_ = new map<string, updateRecord>();
	dataNew_ = new map<string, updateRecord>();
	dataOld_ = new map<string, updateRecord>();

	//功能选择
	int funcn = chooseFunc();

	while (funcn==1 || funcn == 2)
	{
		if (funcn == 1) {
			cout << "功能1-------保存文件MD5\n" << endl;
			function1();
		}
		else if (funcn == 2) {
			cout << "功能2-------对比两个md5文件差异\n" << endl;
			function2();
		}
		/*else if (funcn == 3) {
			cout << "----test----\n" << endl;
		}*/

		funcn = chooseFunc();
	}

	return 0;
}

#pragma once
#include <string>
using std::wstring;
using namespace std;

#ifndef ULONG
typedef unsigned long ULONG;
#endif
#ifndef UINT
typedef unsigned int UINT;
#endif

#define MD5FILE 1
#define MD5STRING 2

wstring CalcMD5(int i_type, string lpcw_str);
wstring CalcFileMD5(string file_path);
wstring CalcStringMD5(int i_type, string str_name);


/* Data structure for MD5 (Message Digest) computation */
typedef struct {
	ULONG i[2];                   /* Number of _bits_ handled mod 2^64 */
	ULONG buf[4];                                    /* Scratch buffer */
	wchar_t in[64];                              /* Input buffer */
	wchar_t digest[16];     /* Actual digest after MD5Final call */
} MD5_CTX;

class MD5Hash
{
public:
	MD5Hash(void);
	~MD5Hash(void);
	void MD5_Transform(ULONG *buf, ULONG *in);
	void MD5Init(MD5_CTX *mdContext, ULONG pseudoRandomNumber = 0);
	void MD5Update(MD5_CTX *mdContext, wchar_t *inBuf, UINT inLen);
	void MD5Final(MD5_CTX *mdContext);
	int md5file(const wchar_t *fn , ULONG seed , MD5_CTX *mdContext) ;
};

MD5Hash.cpp

#include "StdAfx.h"
#include "MD5Hash.h"

wstring CalcMD5(int i_type, string lpcw_str)
{
	wstring result;
	if (i_type == MD5FILE) {
	}
	return 0;
}

wstring CalcFileMD5(string file_path)
{
	MD5Hash m_md5;
	MD5_CTX m_md5_ctx;
	wstring result;
	wchar_t tmp[3];

	FILE *fileToHash = NULL;
	//wstring fileName = file_path;
	std::wstring fileName(file_path.length(), L' ');
	std::copy(file_path.begin(), file_path.end(), fileName.begin());

	if(fileName.empty()) {
		return _T("");
	}
	if(m_md5.md5file(fileName.c_str(), 0, &m_md5_ctx)) {
		for(int i = 0; i < 16; i++) {
			//_itoa(m_md5_ctx.digest[i], tmp, 16);
			_itow_s(m_md5_ctx.digest[i], tmp, 16);

			if(wcsnlen_s(tmp, 3) == 1) {
				tmp[1] = tmp[0];
				tmp[0] = '0';
				tmp[2] = '\0';
			}

			result += tmp;
		}
	}
	return result;
}

wstring CalcStringMD5(int i_type, string str_name)
{
	return 0;
}

MD5Hash::MD5Hash(void)
{
}


MD5Hash::~MD5Hash(void)
{
}

/* Padding */
static wchar_t MD5_PADDING[64] = {
	0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

/* MD5_F, MD5_G and MD5_H are basic MD5 functions: selection, majority, parity */
#define MD5_F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define MD5_G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define MD5_H(x, y, z) ((x) ^ (y) ^ (z))
#define MD5_I(x, y, z) ((y) ^ ((x) | (~z)))

/* ROTATE_LEFT rotates x left n bits */
#ifndef ROTATE_LEFT
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
#endif

/* MD5_FF, MD5_GG, MD5_HH, and MD5_II transformations for rounds 1, 2, 3, and 4 */
/* Rotation is separate from addition to prevent recomputation */
#define MD5_FF(a, b, c, d, x, s, ac) {(a) += MD5_F ((b), (c), (d)) + (x) + (ULONG)(ac); (a) = ROTATE_LEFT ((a), (s)); (a) += (b); }
#define MD5_GG(a, b, c, d, x, s, ac) {(a) += MD5_G ((b), (c), (d)) + (x) + (ULONG)(ac); (a) = ROTATE_LEFT ((a), (s)); (a) += (b); }
#define MD5_HH(a, b, c, d, x, s, ac) {(a) += MD5_H ((b), (c), (d)) + (x) + (ULONG)(ac); (a) = ROTATE_LEFT ((a), (s)); (a) += (b); }
#define MD5_II(a, b, c, d, x, s, ac) {(a) += MD5_I ((b), (c), (d)) + (x) + (ULONG)(ac); (a) = ROTATE_LEFT ((a), (s)); (a) += (b); }

/* Constants for transformation */
#define MD5_S11 7  /* Round 1 */
#define MD5_S12 12
#define MD5_S13 17
#define MD5_S14 22
#define MD5_S21 5  /* Round 2 */
#define MD5_S22 9
#define MD5_S23 14
#define MD5_S24 20
#define MD5_S31 4  /* Round 3 */
#define MD5_S32 11
#define MD5_S33 16
#define MD5_S34 23
#define MD5_S41 6  /* Round 4 */
#define MD5_S42 10
#define MD5_S43 15
#define MD5_S44 21

void MD5Hash::MD5_Transform( ULONG *buf, ULONG *in )
{
	ULONG a = buf[0], b = buf[1], c = buf[2], d = buf[3];

	/* Round 1 */
	MD5_FF ( a, b, c, d, in[ 0], MD5_S11, (ULONG) 3614090360u); /* 1 */
	MD5_FF ( d, a, b, c, in[ 1], MD5_S12, (ULONG) 3905402710u); /* 2 */
	MD5_FF ( c, d, a, b, in[ 2], MD5_S13, (ULONG)  606105819u); /* 3 */
	MD5_FF ( b, c, d, a, in[ 3], MD5_S14, (ULONG) 3250441966u); /* 4 */
	MD5_FF ( a, b, c, d, in[ 4], MD5_S11, (ULONG) 4118548399u); /* 5 */
	MD5_FF ( d, a, b, c, in[ 5], MD5_S12, (ULONG) 1200080426u); /* 6 */
	MD5_FF ( c, d, a, b, in[ 6], MD5_S13, (ULONG) 2821735955u); /* 7 */
	MD5_FF ( b, c, d, a, in[ 7], MD5_S14, (ULONG) 4249261313u); /* 8 */
	MD5_FF ( a, b, c, d, in[ 8], MD5_S11, (ULONG) 1770035416u); /* 9 */
	MD5_FF ( d, a, b, c, in[ 9], MD5_S12, (ULONG) 2336552879u); /* 10 */
	MD5_FF ( c, d, a, b, in[10], MD5_S13, (ULONG) 4294925233u); /* 11 */
	MD5_FF ( b, c, d, a, in[11], MD5_S14, (ULONG) 2304563134u); /* 12 */
	MD5_FF ( a, b, c, d, in[12], MD5_S11, (ULONG) 1804603682u); /* 13 */
	MD5_FF ( d, a, b, c, in[13], MD5_S12, (ULONG) 4254626195u); /* 14 */
	MD5_FF ( c, d, a, b, in[14], MD5_S13, (ULONG) 2792965006u); /* 15 */
	MD5_FF ( b, c, d, a, in[15], MD5_S14, (ULONG) 1236535329u); /* 16 */

	/* Round 2 */
	MD5_GG ( a, b, c, d, in[ 1], MD5_S21, (ULONG) 4129170786u); /* 17 */
	MD5_GG ( d, a, b, c, in[ 6], MD5_S22, (ULONG) 3225465664u); /* 18 */
	MD5_GG ( c, d, a, b, in[11], MD5_S23, (ULONG)  643717713u); /* 19 */
	MD5_GG ( b, c, d, a, in[ 0], MD5_S24, (ULONG) 3921069994u); /* 20 */
	MD5_GG ( a, b, c, d, in[ 5], MD5_S21, (ULONG) 3593408605u); /* 21 */
	MD5_GG ( d, a, b, c, in[10], MD5_S22, (ULONG)   38016083u); /* 22 */
	MD5_GG ( c, d, a, b, in[15], MD5_S23, (ULONG) 3634488961u); /* 23 */
	MD5_GG ( b, c, d, a, in[ 4], MD5_S24, (ULONG) 3889429448u); /* 24 */
	MD5_GG ( a, b, c, d, in[ 9], MD5_S21, (ULONG)  568446438u); /* 25 */
	MD5_GG ( d, a, b, c, in[14], MD5_S22, (ULONG) 3275163606u); /* 26 */
	MD5_GG ( c, d, a, b, in[ 3], MD5_S23, (ULONG) 4107603335u); /* 27 */
	MD5_GG ( b, c, d, a, in[ 8], MD5_S24, (ULONG) 1163531501u); /* 28 */
	MD5_GG ( a, b, c, d, in[13], MD5_S21, (ULONG) 2850285829u); /* 29 */
	MD5_GG ( d, a, b, c, in[ 2], MD5_S22, (ULONG) 4243563512u); /* 30 */
	MD5_GG ( c, d, a, b, in[ 7], MD5_S23, (ULONG) 1735328473u); /* 31 */
	MD5_GG ( b, c, d, a, in[12], MD5_S24, (ULONG) 2368359562u); /* 32 */

	/* Round 3 */
	MD5_HH ( a, b, c, d, in[ 5], MD5_S31, (ULONG) 4294588738u); /* 33 */
	MD5_HH ( d, a, b, c, in[ 8], MD5_S32, (ULONG) 2272392833u); /* 34 */
	MD5_HH ( c, d, a, b, in[11], MD5_S33, (ULONG) 1839030562u); /* 35 */
	MD5_HH ( b, c, d, a, in[14], MD5_S34, (ULONG) 4259657740u); /* 36 */
	MD5_HH ( a, b, c, d, in[ 1], MD5_S31, (ULONG) 2763975236u); /* 37 */
	MD5_HH ( d, a, b, c, in[ 4], MD5_S32, (ULONG) 1272893353u); /* 38 */
	MD5_HH ( c, d, a, b, in[ 7], MD5_S33, (ULONG) 4139469664u); /* 39 */
	MD5_HH ( b, c, d, a, in[10], MD5_S34, (ULONG) 3200236656u); /* 40 */
	MD5_HH ( a, b, c, d, in[13], MD5_S31, (ULONG)  681279174u); /* 41 */
	MD5_HH ( d, a, b, c, in[ 0], MD5_S32, (ULONG) 3936430074u); /* 42 */
	MD5_HH ( c, d, a, b, in[ 3], MD5_S33, (ULONG) 3572445317u); /* 43 */
	MD5_HH ( b, c, d, a, in[ 6], MD5_S34, (ULONG)   76029189u); /* 44 */
	MD5_HH ( a, b, c, d, in[ 9], MD5_S31, (ULONG) 3654602809u); /* 45 */
	MD5_HH ( d, a, b, c, in[12], MD5_S32, (ULONG) 3873151461u); /* 46 */
	MD5_HH ( c, d, a, b, in[15], MD5_S33, (ULONG)  530742520u); /* 47 */
	MD5_HH ( b, c, d, a, in[ 2], MD5_S34, (ULONG) 3299628645u); /* 48 */

	/* Round 4 */
	MD5_II ( a, b, c, d, in[ 0], MD5_S41, (ULONG) 4096336452u); /* 49 */
	MD5_II ( d, a, b, c, in[ 7], MD5_S42, (ULONG) 1126891415u); /* 50 */
	MD5_II ( c, d, a, b, in[14], MD5_S43, (ULONG) 2878612391u); /* 51 */
	MD5_II ( b, c, d, a, in[ 5], MD5_S44, (ULONG) 4237533241u); /* 52 */
	MD5_II ( a, b, c, d, in[12], MD5_S41, (ULONG) 1700485571u); /* 53 */
	MD5_II ( d, a, b, c, in[ 3], MD5_S42, (ULONG) 2399980690u); /* 54 */
	MD5_II ( c, d, a, b, in[10], MD5_S43, (ULONG) 4293915773u); /* 55 */
	MD5_II ( b, c, d, a, in[ 1], MD5_S44, (ULONG) 2240044497u); /* 56 */
	MD5_II ( a, b, c, d, in[ 8], MD5_S41, (ULONG) 1873313359u); /* 57 */
	MD5_II ( d, a, b, c, in[15], MD5_S42, (ULONG) 4264355552u); /* 58 */
	MD5_II ( c, d, a, b, in[ 6], MD5_S43, (ULONG) 2734768916u); /* 59 */
	MD5_II ( b, c, d, a, in[13], MD5_S44, (ULONG) 1309151649u); /* 60 */
	MD5_II ( a, b, c, d, in[ 4], MD5_S41, (ULONG) 4149444226u); /* 61 */
	MD5_II ( d, a, b, c, in[11], MD5_S42, (ULONG) 3174756917u); /* 62 */
	MD5_II ( c, d, a, b, in[ 2], MD5_S43, (ULONG)  718787259u); /* 63 */
	MD5_II ( b, c, d, a, in[ 9], MD5_S44, (ULONG) 3951481745u); /* 64 */

	buf[0] += a;
	buf[1] += b;
	buf[2] += c;
	buf[3] += d;
}

void MD5Hash::MD5Init( MD5_CTX *mdContext, ULONG pseudoRandomNumber /*= 0*/ )
{
	mdContext->i[0] = mdContext->i[1] = (ULONG)0;

	/* Load magic initialization constants */
	mdContext->buf[0] = (ULONG)0x67452301 + (pseudoRandomNumber * 11);
	mdContext->buf[1] = (ULONG)0xefcdab89 + (pseudoRandomNumber * 71);
	mdContext->buf[2] = (ULONG)0x98badcfe + (pseudoRandomNumber * 37);
	mdContext->buf[3] = (ULONG)0x10325476 + (pseudoRandomNumber * 97);
}

void MD5Hash::MD5Update( MD5_CTX *mdContext, wchar_t *inBuf, UINT inLen )
{
	ULONG in[16];
	int mdi = 0;
	unsigned int i = 0, ii = 0;

	/* Compute number of bytes mod 64 */
	mdi = (int)((mdContext->i[0] >> 3) & 0x3F);

	/* Update number of bits */
	if ((mdContext->i[0] + ((ULONG)inLen << 3)) < mdContext->i[0]) {
		mdContext->i[1]++;
	}
	mdContext->i[0] += ((ULONG)inLen << 3);
	mdContext->i[1] += ((ULONG)inLen >> 29);

	while (inLen--) {
		/* Add new character to buffer, increment mdi */
		mdContext->in[mdi++] = *inBuf++;

		/* Transform if necessary */
		if (mdi == 0x40) {
			for (i = 0, ii = 0; i < 16; i++, ii += 4)
				in[i] = (((ULONG)mdContext->in[ii + 3]) << 24) |
				        (((ULONG)mdContext->in[ii + 2]) << 16) |
				        (((ULONG)mdContext->in[ii + 1]) << 8) |
				        ((ULONG)mdContext->in[ii]);

			MD5_Transform (mdContext->buf, in);
			mdi = 0;
		}
	}
}

void MD5Hash::MD5Final( MD5_CTX *mdContext )
{
	ULONG in[16];
	int mdi = 0;
	unsigned int i = 0, ii = 0, padLen = 0;

	/* Save number of bits */
	in[14] = mdContext->i[0];
	in[15] = mdContext->i[1];

	/* Compute number of bytes mod 64 */
	mdi = (int)((mdContext->i[0] >> 3) & 0x3F);

	/* Pad out to 56 mod 64 */
	padLen = (mdi < 56) ? (56 - mdi) : (120 - mdi);
	MD5Update (mdContext, MD5_PADDING, padLen);

	/* Append length in bits and transform */
	for (i = 0, ii = 0; i < 14; i++, ii += 4)
		in[i] = (((ULONG)mdContext->in[ii + 3]) << 24) |
		        (((ULONG)mdContext->in[ii + 2]) << 16) |
		        (((ULONG)mdContext->in[ii + 1]) <<  8) |
		        ((ULONG)mdContext->in[ii]);
	MD5_Transform (mdContext->buf, in);

	/* Store buffer in digest */
	for (i = 0, ii = 0; i < 4; i++, ii += 4) {
		mdContext->digest[ii]   = (unsigned char)( mdContext->buf[i]        & 0xFF);
		mdContext->digest[ii + 1] = (unsigned char)((mdContext->buf[i] >>  8) & 0xFF);
		mdContext->digest[ii + 2] = (unsigned char)((mdContext->buf[i] >> 16) & 0xFF);
		mdContext->digest[ii + 3] = (unsigned char)((mdContext->buf[i] >> 24) & 0xFF);
	}
}

int MD5Hash::md5file( const wchar_t *fn , ULONG seed , MD5_CTX *mdContext )
{
	ULONG size = 0;
	FILE *f;
	_wfopen_s(&f, fn, _T("rb"));

	if(f == NULL) {
		return 0 ;
	}

	MD5Init(mdContext , seed) ;
	wchar_t buf[2048] ;
	UINT trb = 0 ;

	for(;;) {
		int rb = fread(buf , 1 , 2048 , f) ;

		if(size > 0 && rb + trb > size) {
			rb = size - trb ;
		}

		trb += rb ;
		MD5Update(mdContext , buf , rb) ;

		if(rb < 2048 || (size > 0 && trb >= size)) {
			break ;
		}
	}

	fclose(f) ;
	MD5Final(mdContext) ;
	return trb ;
}

对比文件MD5差异并保存

标签：c++   md5   文件操作   

原文地址：http://blog.csdn.net/daydayup_chf/article/details/46534137