文件打包代码更新 使用json记录打包文件信息

经过之前的几次试验 决定使用json记录打包文件信息

#include "Package.h"

#include "json/json.h"

#include <string>

#include <iostream>

 

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bool Package::CreatePackage(const char* packFileName) {

    bool bRet = false;

 

    fpPackage_ = fopen(packFileName,"wb+");

    if (NULL == fpPackage_)

        return bRet;

 

    bRet = true;

    return bRet;

}

 

void Package::AddFileToList(const char* fileName) {

    fileList.push_back(fileName);

}

 

bool Package::OpenPackageForUnPack(const char* packFileName) {

    if (NULL != fpPackage_)

        fclose(fpPackage_);

 

    fpPackage_ = fopen(packFileName, "rb");

    if (NULL == fpPackage_)

        return false;

 

    return true;

}

 

bool Package::CopyFileContent(FILE* src, FILE* dsc) {

    char* buf = new char[CopyBufSize];

    if (NULL == buf)

        return false;

 

    while (1) {

        int nReadBytes = fread(buf,1, CopyBufSize, src);

        //写入包裹

        fwrite(buf, 1, nReadBytes, dsc);

        //如果读取到的数据比缓冲区小，那么说明读取结束了

        if (nReadBytes < sizeof(buf))

        {

            break;

        }

    }

    //fflush是确保我们的数据写入到磁盘上了

    fflush(dsc);

    return true;

}

 

bool  Package::PackageOneFile(const char*name)

{

    bool bRet = false;

 

    FILE* fp = fopen(name, "rb");

    if (NULL == fp)

    return bRet;

 

    //获取文件长度

    _fseeki64(fp, 0, SEEK_END); //定位到文件末

    __int64 filelength = _ftelli64(fp);

    _fseeki64(fp, 0, SEEK_SET);

 

    //获取PACKAGE文件当前偏移

    __int64 currentOffset = _ftelli64(fpPackage_);

 

    //开始打包

    CopyFileContent(fp, fpPackage_);

 

    FILEINFO fileInfo;

    fileInfo.filename = name;

    fileInfo.fileSize = filelength;

    fileInfo.offsetInPackFile = currentOffset;

 

    fileInfoList.push_back(fileInfo);

    fclose(fp);

    return bRet;

}

 

bool Package::GetUnpackFileInfo() {

    fileInfoList.clear();

    __int64 jsonOffset = 0;

    fread(&jsonOffset,1,sizeof(jsonOffset), fpPackage_);

 

    //获取文件长度

    _fseeki64(fpPackage_, 0, SEEK_END); //定位到文件末

    __int64 filelength = _ftelli64(fpPackage_);

    _fseeki64(fpPackage_, 0, SEEK_SET);

 

    _fseeki64(fpPackage_, jsonOffset, SEEK_SET);

    char* jsonBuf = new char[filelength - jsonOffset];

    if (NULL == jsonBuf)

        return false;

    fread(jsonBuf,filelength - jsonOffset,1, fpPackage_);

 

    //解析json字符串

    Json::Reader pJsonParser;;

    Json::Value tempVal;

 

    if (!pJsonParser.parse(jsonBuf, tempVal))

    {

        std::cout << "parse error" << std::endl;

        delete[] jsonBuf;

        return false;

    }

 

    Json::Value array = tempVal["array"];

    for (int i = 0; i < array.size(); i++) {

        std::cout << array[i]["Filename"].asString() << std::endl;

        std::cout << array[i]["FileSize"].asInt64() << std::endl;

        std::cout << array[i]["Offset"].asInt64() << std::endl;

    }

 

    delete[] jsonBuf;

    return true;

}

 

 

bool Package::WriteFileInfoToPackFile() {

 

    //获取PACKAGE文件当前偏移 写入JSON文件信息的偏移

    __int64 currentOffset = _ftelli64(fpPackage_);

    //生成JSON

    Json::Value root;

    Json::Value array;

    Json::FastWriter writer;

    Json::Value fileInfo;

 

    for (std::deque<FILEINFO>::iterator it = fileInfoList.begin();

        it != fileInfoList.end(); it++) {

        fileInfo["Filename"] = it->filename;

        fileInfo["FileSize"] = it->fileSize;

        fileInfo["Offset"] = it->offsetInPackFile;

        array.append(fileInfo);

    }

    root["array"] = array;

     

    std::string s = writer.write(root);

 

    //写入文件信息

    fwrite(s.c_str(),1,s.size(), fpPackage_);

 

    //跳转到文件头 写入JOSN偏移

    _fseeki64(fpPackage_, 0, SEEK_SET);

    fwrite(&currentOffset,1,sizeof(currentOffset), fpPackage_);

    fflush(fpPackage_);

    return true;

}

 

bool Package::PackFile() {

    bool bRet = false;

    //预留 打包文件的信息的偏移位置

    __int64 jsonOffset = 0;

    fwrite(&jsonOffset, 1, sizeof(jsonOffset), fpPackage_);

    for (std::deque<std::string>::iterator it = fileList.begin();

        it != fileList.end(); it++) {

        std::string fileName = *it;

        PackageOneFile(fileName.c_str());

    }

    fileList.clear();

    WriteFileInfoToPackFile();

 

    return bRet;

}

 

打包文件格式如下

文件信息格式类似

代码运行结果

具体代码见

http://www.oschina.net/code/snippet_614253_56938