您现在的位置：程式碼之家 >> 編程語言 > >> 網頁程式設計 >> PHP 程式設計 >> PHP 綜合知識

PHP TCP 端口檢測類：Health 非阻塞連接實現

編輯：PHP 綜合知識

核心原理

使用 socket_create + socket_set_nonblock + socket_connect + socket_select 實現帶超時的非阻塞連接，避免 fsockopen 無法精確控制連接超時的問題。

完整類代碼

<?php
class Health {
    public static $status;

    public function check($ip, $port) {
        $sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
        if (!$sock) return false;

        socket_set_nonblock($sock);
        @socket_connect($sock, $ip, $port); // 非阻塞下立即返回
        socket_set_block($sock);            // 恢復阻塞模式供 select 使用

        // select 監聽寫就緒（連接建立）或異常，超時 5 秒
        $r = [$sock]; $w = [$sock]; $e = [$sock];
        self::$status = socket_select($r, $w, $e, 5);

        socket_close($sock);
        return self::$status;
    }

    public function status() {
        switch (self::$status) {
            case 1: echo "Open\n"; break;   // 可寫 → 連接成功
            case 0: echo "Timeout\n"; break; // 超時
            default: echo "Closed/Error\n"; break; // 異常/拒絕
        }
    }
}

// 使用
$health = new Health();
$health->check('192.168.2.10', 80);
$health->status();

狀態碼含義

返回值	含義	socket_select 就緒數組
1	端口開放（連接成功）	$w 包含 socket
0	超時（5 秒內無響應）	三個數組均為空
-1 / false	錯誤（創建失敗、權限等）	—

進階：批量檢測與異步並發

function checkPorts(array $targets, $timeout=3) {
    $sockets = [];
    foreach ($targets as $i => [$ip, $port]) {
        $sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
        socket_set_nonblock($sock);
        @socket_connect($sock, $ip, $port);
        $sockets[$i] = ['sock'=>$sock, 'ip'=>$ip, 'port'=>$port];
    }

    $start = microtime(true);
    $results = [];
    while ($sockets && microtime(true) - $start < $timeout) {
        $r = []; $w = []; $e = [];
        foreach ($sockets as $i => $s) {
            $w[] = $s['sock']; $e[] = $s['sock'];
        }
        $n = @socket_select($r, $w, $e, 0, 500000); // 0.5 秒輪詢
        if ($n > 0) {
            foreach ($w as $sock) {
                foreach ($sockets as $i => $s) {
                    if ($s['sock'] === $sock) {
                        $results[$i] = ['ip'=>$s['ip'], 'port'=>$s['port'], 'status'=>'open'];
                        socket_close($sock);
                        unset($sockets[$i]);
                        break;
                    }
                }
            }
            foreach ($e as $sock) {
                foreach ($sockets as $i => $s) {
                    if ($s['sock'] === $sock && isset($sockets[$i])) {
                        $results[$i] = ['ip'=>$s['ip'], 'port'=>$s['port'], 'status'=>'error'];
                        socket_close($sock);
                        unset($sockets[$i]);
                        break;
                    }
                }
            }
        }
    }
    // 剩餘為 timeout
    foreach ($sockets as $i => $s) {
        $results[$i] = ['ip'=>$s['ip'], 'port'=>$s['port'], 'status'=>'timeout'];
        socket_close($s['sock']);
    }
    return $results;
}