ClamAV学习【2】——clamscan入口函数浏览

就简单给代码加上些注释，方便理解。第一次浏览，应该会有不正确的理解。后面会继续学习修改。

文件：clamscan\clamscan.c

代码如下：

nt main(int argc, char **argv)
{
    int ds, dms, ret;
    double mb;
    struct timeval t1, t2;
#ifndef C_WINDOWS
    struct timezone tz;
#endif
    struct optstruct *opt;
    const char *pt;  

    //pthread是一个通用的跨平台高性能线程库
    //暂时没发现加入的地方
    //在程序开始的时候要调用
#if defined(C_WINDOWS) && defined(CL_THREAD_SAFE)
    if(!pthread_win32_process_attach_np()) {
    mprintf("!Can't start the win32 pthreads layer\n");
    return 72;
    }
#endif  

    //这里进行参数解析
    //具体规则待会查看下
    opt = opt_parse(argc, argv, clamscan_shortopt, clamscan_longopt, NULL);
    if(!opt) {
    mprintf("!Can't parse the command line\n");
    return 40;
    }  

    //以下开始进行命令判断
    if(opt_check(opt, "verbose")) {
    mprintf_verbose = 1;
    logg_verbose = 1;
    }  

    if(opt_check(opt, "quiet"))
    mprintf_quiet = 1;  

    if(opt_check(opt, "stdout"))
    mprintf_stdout = 1;  

    if(opt_check(opt, "debug")) {
#if defined(C_LINUX)
        /* [e-mail]: create a dump if needed */
        struct rlimit rlim;  

    rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
    if(setrlimit(RLIMIT_CORE, &rlim) < 0)
        perror("setrlimit");
#endif
    cl_debug(); /* enable debug messages */
    }  

    if(opt_check(opt, "version")) {
    print_version(opt_arg(opt, "database"));
    opt_free(opt);
    return 0;
    }  

    if(opt_check(opt, "help")) {
    opt_free(opt);
        help();
    return 0;
    }  

    if(opt_check(opt, "recursive"))
    recursion = 1;  

    if(opt_check(opt, "infected"))
    printinfected = 1;  

    if(opt_check(opt, "bell"))
    bell = 1;  

    if(opt_check(opt, "tempdir"))
    cl_settempdir(opt_arg(opt, "tempdir"), 0);  

    if(opt_check(opt, "leave-temps"))
    cl_settempdir(NULL, 1);  

    //日志初始化
    if(opt_check(opt, "log")) {
    logg_file = opt_arg(opt, "log");
    if(logg("#\n-------------------------------------------------------------------------------\n\n")) {
        mprintf("!Problem with internal logger.\n");
        opt_free(opt);
        return 62;
    }
    } else
    logg_file = NULL;  

    //一些数字参数合法化检验  

    if(opt_check(opt, "max-scansize")) {
    pt = opt_arg(opt, "max-scansize");
    if(!strchr(pt, 'M') && !strchr(pt, 'm')) {
        if(!cli_isnumber(pt)) {
        logg("!--max-scansize requires a natural number\n");
        opt_free(opt);
        return 40;
        }
    }
    }  

    if(opt_check(opt, "max-filesize")) {
    pt = opt_arg(opt, "max-filesize");
    if(!strchr(pt, 'M') && !strchr(pt, 'm')) {
        if(!cli_isnumber(pt)) {
        logg("!--max-filesize requires a natural number\n");
        opt_free(opt);
        return 40;
        }
    }
    }  

    if(opt_check(opt, "max-files")) {
    if(!cli_isnumber(opt_arg(opt, "max-files"))) {
        logg("!--max-files requires a natural number\n");
        opt_free(opt);
        return 40;
    }
    }  

    if(opt_check(opt, "max-recursion")) {
    if(!cli_isnumber(opt_arg(opt, "max-recursion"))) {
        logg("!--max-recursion requires a natural number\n");
        opt_free(opt);
        return 40;
    }
    }  

    if(opt_check(opt, "max-mail-recursion")) {
    if(!cli_isnumber(opt_arg(opt, "max-mail-recursion"))) {
        logg("!--max-mail-recursion requires a natural number\n");
        opt_free(opt);
        return 40;
    }
    }  

    if(opt_check(opt, "max-dir-recursion")) {
    if(!cli_isnumber(opt_arg(opt, "max-dir-recursion"))) {
        logg("!--max-dir-recursion requires a natural number\n");
        opt_free(opt);
        return 40;
    }
    }  

    if(opt_check(opt, "max-ratio")) {
    if(!cli_isnumber(opt_arg(opt, "max-ratio"))) {
        logg("!--max-ratio requires a natural number\n");
        opt_free(opt);
        return 40;
    }
    }  

    memset(&info, 0, sizeof(struct s_info));  

    //设置默认的文件I/O操作
    //Windows下二进制
    //DEBUG下设置报告方式？
#ifdef C_WINDOWS
    _set_fmode(_O_BINARY);
#ifdef CL_DEBUG
    {
    _CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_FILE);
    _CrtSetReportFile(_CRT_ERROR, _CRTDBG_FILE_STDERR);
    }
#endif
    gettimeofday(&t1, NULL);
#else
    gettimeofday(&t1, &tz);
#endif  

    //这里就开始调用一个扫描的管理类方法来扫毒
    //返回的ret说明信息
    ret = scanmanager(opt);  

    //下面开始就是日志记录？
    if(!opt_check(opt, "disable-summary") && !opt_check(opt, "no-summary")) {
#ifdef C_WINDOWS
    gettimeofday(&t2, NULL);
#else
    gettimeofday(&t2, &tz);
#endif
    ds = t2.tv_sec - t1.tv_sec;
    dms = t2.tv_usec - t1.tv_usec;
    ds -= (dms < 0) ? (1):(0);
    dms += (dms < 0) ? (1000000):(0);
    logg("\n----------- SCAN SUMMARY -----------\n");
    logg("Known viruses: %u\n", info.sigs);
    logg("Engine version: %s\n", cl_retver());
    logg("Scanned directories: %u\n", info.dirs);
    logg("Scanned files: %u\n", info.files);
    logg("Infected files: %u\n", info.ifiles);
    if(info.notremoved) {
        logg("Not removed: %u\n", info.notremoved);
    }
    if(info.notmoved) {
        logg("Not %s: %u\n", opt_check(opt, "copy") ? "moved" : "copied", info.notmoved);
    }
    mb = info.blocks * (CL_COUNT_PRECISION / 1024) / 1024.0;
    logg("Data scanned: %2.2lf MB\n", mb);
    logg("Time: %u.%3.3u sec (%u m %u s)\n", ds, dms/1000, ds/60, ds%60);
    }  

    opt_free(opt);  

    //对应于上面的pthread开始函数
#if defined(C_WINDOWS) && defined(CL_THREAD_SAFE)
    if(!pthread_win32_process_detach_np()) {
    logg("!Can't stop the win32 pthreads layer\n");
    return 72;
    }
#endif  

    return ret;
}

原文：http://blog.csdn.net/betabin/article/details/7421910