download

1.创建目录

(1)

void UpdateLayer::createDownloadedDir()

{

    pathToSave =CCFileUtils::sharedFileUtils()->getWritablePath();

    pathToSave +="tmpdir";

    

    // Create the folder if it doesn't exist

#if (CC_TARGET_PLATFORM != CC_PLATFORM_WIN32)

    DIR *pDir =NULL;

    pDir = opendir (pathToSave.c_str());

    if (! pDir)

    {

        mkdir(pathToSave.c_str(),S_IRWXU | S_IRWXG |S_IRWXO);                                    //目录属性设置：S_IRWXU、S_IRWXG、S_IRWXO

    }

#else

if ((GetFileAttributesA(pathToSave.c_str())) == INVALID_FILE_ATTRIBUTES)               //windows平台

{

CreateDirectoryA(pathToSave.c_str(),0);

}

#endif

}

(2)

bool AssetsManager::createDirectory(constchar *path)

{

#if (CC_TARGET_PLATFORM != CC_PLATFORM_WIN32)

    mode_t processMask =umask(0);                                                                                                    //umask：linux系统设置文件权限

    int ret =mkdir(path, S_IRWXU |S_IRWXG | S_IRWXO);                                                                //

    umask(processMask);

    if (ret !=0 && (errno !=EEXIST))

    {

        returnfalse;

    }

    returntrue;

#else

    BOOL ret = CreateDirectoryA(path, NULL);

if (!ret && ERROR_ALREADY_EXISTS != GetLastError())

{

returnfalse;

}

    returntrue;

#endif

}

2.删除某个目录下所有文件

voidUpdateLayer::reset(cocos2d::CCObject *pSender)

{

    // Remove downloaded files

#if (CC_TARGET_PLATFORM != CC_PLATFORM_WIN32)

    string command ="rm -r ";                                                                                 //命令删除

    // Path may include space.

    command += "\"" +pathToSave +"\"";

    system(command.c_str());

#else

    string command = "rd /s /q ";                                                                              //命令删除

    // Path may include space.

    command += "\"" + pathToSave +"\"";

    system(command.c_str());

#endif

}

3.AssetsManager类实现下载

(1)下载资源

//文件里写下载内容

static size_t downLoadPackage(void *ptr,size_t size, size_t nmemb,void *userdata)

{

    CCLog("static size_t downLoadPackage(void *ptr, size_t size, size_t nmemb, void *userdata)");

    FILE *fp = (FILE*)userdata;

    size_t written =fwrite(ptr, size, nmemb, fp);

    return written;

}

//记录下载进度

static int progressFunc(void *ptr,double totalToDownload,double nowDownloaded, double totalToUpLoad, double nowUpLoaded)

{

    CCLOG("downloading... %d%%", (int)(nowDownloaded/totalToDownload*100));

    CCLog("-----------");

    

    return0;

}

//#define TEMP_PACKAGE_FILE_NAME    "cocos2dx-update-temp-package.zip"

bool AssetsManager::downLoad()

{

    string outFileName =_storagePath + TEMP_PACKAGE_FILE_NAME;                    //_storagePath存储路径

    FILE *fp =fopen(outFileName.c_str(),"wb");

    if (! fp)

    {

        CCLOG("can not create file %s", outFileName.c_str());

        returnfalse;

    }

    CURLcode res;                                                                                                              //CURLcode枚举成功失败对应的编号

    

    /*下载地址、执行下载函数、写文件指针、？？、下载进度查看、执行、清理*/

    curl_easy_setopt(_curl,CURLOPT_URL,_packageUrl.c_str());

    curl_easy_setopt(_curl,CURLOPT_WRITEFUNCTION, downLoadPackage);

    curl_easy_setopt(_curl,CURLOPT_WRITEDATA, fp); //fp指针

    curl_easy_setopt(_curl,CURLOPT_NOPROGRESS, false);

    curl_easy_setopt(_curl,CURLOPT_PROGRESSFUNCTION,progressFunc);

    res = curl_easy_perform(_curl);

    curl_easy_cleanup(_curl);

    //执行结果

    if (res !=0)

    {

        CCLOG("error when download package");

        fclose(fp);

        returnfalse;

    }

    //全部下载完成

    CCLOG("succeed downloading package %s",_packageUrl.c_str());

    fclose(fp);

    returntrue;

}

(2)网络文字下载

//检查版本

static size_t getVersionCode(void *ptr, size_t size, size_t nmemb, void *userdata)

{

    string *version = (string*)userdata;

    version->append((char*)ptr, size * nmemb);

    return (size * nmemb);

}

//网络连接

bool AssetsManager::checkUpdate()

{

    if (_versionFileUrl.size() == 0) return false;

       _curl = curl_easy_init();

    if (! _curl)

    {

        CCLOG("can not init curl");

        return false;

    }

    _version.clear();

    

    CURLcode res;

    curl_easy_setopt(_curl, CURLOPT_URL, _versionFileUrl.c_str());

    curl_easy_setopt(_curl, CURLOPT_SSL_VERIFYPEER, 0L);

    curl_easy_setopt(_curl, CURLOPT_WRITEFUNCTION, getVersionCode);

    curl_easy_setopt(_curl, CURLOPT_WRITEDATA, &_version);                                      //_version：直接写字符串

    res = curl_easy_perform(_curl);

    

    if (res != 0)

    {

        CCLOG("can not get version file content, error code is %d", res);

        curl_easy_cleanup(_curl);

        return false;

    }

    

    string recordedVersion = CCUserDefault::sharedUserDefault()->getStringForKey(KEY_OF_VERSION);

    if (recordedVersion == _version)

    {

        CCLOG("there is not new version");

        // Set resource search path.

        setSearchPath();

        return false;

    }

    CCLOG("there is a new version: %s", _version.c_str());

    return true;

}