[测试]socket_read和socket_recvfrom 单次ping[B君笔记][博客]

noscript{position: fixed}[测试]socket_read和socket_recvfrom 单次pingsocketphppingicmp创建时间：2022-01-12 23:30:02

前文

自从[udpate]php ping ipv4 by socket后，我就一直思考socket_sendto + socket_select + socket_recvfrom 与 socket_connect + socket_send + socket_read 之间的区别，两个方案有何不同，有什么差别呢。

socket_read 和 socket_recv 和 socket_recvfrom 区别

socket_read 和 socket_recv

socket_recv returns the number of bytes received socket_read returns the data that has been received

With socket_recv you can read bytes from the buffer AND know how many bytes have been recevied. With socket_read you can only read a specific amount of data from the buffer

socket_recv 和 socket_recvfrom

socket_recv — Receives data from a connected socket
socket_recvfrom — Receives data from a socket whether or not it is connection-oriented

单次ping测试代码

直接写2个版本，用ping来测试一波。

源码

socket_read

<?php
$t = microtime(1);
$host = 'baidu.com';

$type = "\x08";
$code = "\x00";
$checksum = "\x00\x00";
$identifier = "\x00\x00";
$seq_number = "\x00\x00";
$package = $type . $code . $checksum . $identifier . $seq_number . '';

// Calculate the checksum.
$checksum = calculateChecksum($package);

// Finalize the package.
$package = $type . $code . $checksum . $identifier . $seq_number . '';

// Create a socket, connect to server, then read socket and calculate.
if ($socket = socket_create(AF_INET, SOCK_RAW, 1)) {
    socket_set_option($socket, SOL_SOCKET, SO_RCVTIMEO, array(
        'sec' => 0,
        'usec' => 1000*1000,
    ));
    // Prevent errors from being printed when host is unreachable.
    socket_connect($socket, $host, 0);
    $start = microtime(true);
    // Send the package.
    socket_send($socket, $package, strlen($package), 0);
    if (socket_read($socket, 255) !== false) {
        $latency = microtime(true) - $start;
        $latency = round($latency * 1000, 4);
    }
    else {
        $latency = false;
    }
}
else {
    $latency = false;
}
// Close the socket.
socket_close($socket);
echo $latency.PHP_EOL;
echo microtime(1)-$t;

function calculateChecksum($data) {
    if (strlen($data) % 2) {
        $data .= "\x00";
    }

    $bit = unpack('n*', $data);
    $sum = array_sum($bit);

    while ($sum >> 16) {
        $sum = ($sum >> 16) + ($sum & 0xffff);
    }

    return pack('n*', ~$sum);
}

socket_recvfrom

<?php
$t = microtime(1);
$host = 'baidu.com';

$type = "\x08";
$code = "\x00";
$checksum = "\x00\x00";
$identifier = "\x00\x00";
$seq_number = "\x00\x00";
$package = $type . $code . $checksum . $identifier . $seq_number . '';

// Calculate the checksum.
$checksum = calculateChecksum($package);

// Finalize the package.
$package = $type . $code . $checksum . $identifier . $seq_number . '';

// Create a socket, connect to server, then read socket and calculate.
if ($socket = socket_create(AF_INET, SOCK_RAW, 1)) {
    // Prevent errors from being printed when host is unreachable.
    $start = microtime(true);
    // Send the package.
    socket_sendto($socket, $package, strlen($package), 0, $host, 0);
    $latency = false;
    $read = [$socket];
    $write = null;
    $except = null;
    if($select = socket_select($read, $write, $except, 0, 1000 * 1000)){
        if (socket_recvfrom($socket, $recv, 255, 0, $r_host, $r_port)) {
            $latency = microtime(true) - $start;
            $latency = round($latency * 1000, 4);
        }
    }

}
else {
    $latency = false;
}
// Close the socket.
socket_close($socket);
echo $latency.PHP_EOL;
echo microtime(1)-$t;
function calculateChecksum($data) {
    if (strlen($data) % 2) {
        $data .= "\x00";
    }

    $bit = unpack('n*', $data);
    $sum = array_sum($bit);

    while ($sum >> 16) {
        $sum = ($sum >> 16) + ($sum & 0xffff);
    }

    return pack('n*', ~$sum);
}

结果

ping 3 times	ping avg	spend avg
socket_read	50.66436667	0.058893681
socket_recvfrom	58.74896667	0.059391737

代码运行时间并没有太大差别
ping值socket_recvfrom则会稍微偏大，不确定是否有参考意义，实际的话，返回的ping值波动还是比较大的。

参考

PHP socket_recv and socket_read