Add event - Ev::CLOSE for EvIo watcher

[Alex Sky]

Now event CLOSE of the socket, fire as Ev::READ event, you can add a new Ev::CLOSE event, to appoint a separate handler?

Something like this

$loop->io($fd, Ev::CLOSE, function ($w) {...});

[Ruslan Osmanov]

There is no such kind of event as "closed file descriptor(socket)" neither in libev, nor in the back ends supported by libev, AFAIK.

Also, I don't know how to check if a socket is open or closed without actually accessing it(recv or write system calls, for example). You might think of feof() or stream_get_meta_data(), but these won't work with EvIo::$fd because the underlying logic is based on internal flags changed by performing PHP stream operations. So EvIo::$fd is not quite true PHP stream.

Thus, you have to check if corresponding operation on socket succeeds in the Ev::READ callback. For example, a server based on sockets extension might look like the following:

<?php
$address = '127.0.0.1';
$port = 10000;

error_reporting(E_ALL);
ob_implicit_flush();

// Writing to a socket that has been closed by the other end will result in
// the process receiving SIGPIPE signal. The default action for this signal is
// to terminate process. Although it may not happen in PHP, we'll ignore this
// signal explicitly.
pcntl_signal(SIGPIPE, SIG_IGN);


if (($sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP)) === false) {
    fprintf(STDERR, "socket_create failed: %s\n",
        socket_strerror(socket_last_error()) );
    exit(1);
}

if (socket_bind($sock, $address, $port) === false) {
    fprintf(STDERR, "socket_bind failed: %s\n",
        socket_strerror(socket_last_error()) );
    exit(1);
}

if (socket_listen($sock, 5) === false) {
    fprintf(STDERR, "socket_listen failed: %s\n",
        socket_strerror(socket_last_error()) );
    exit(1);
}

do {
    if (($msgsock = socket_accept($sock)) === false) {
        fprintf(STDERR, "socket_accept failed: %s\n",
            socket_strerror(socket_last_error()) );
        break;
    }

    // Set O_NONBLOCK flag
    socket_set_nonblock($msgsock);

    $msg = "Welcome to the test server. To quit tpe 'quit'.\n";
    socket_write($msgsock, $msg, strlen($msg));

    $read_watcher = new EvIo($msgsock, Ev::READ,
        function ($watcher, $events) use ($msgsock)
    {
        if ($events & Ev::ERROR) {
            $watcher->stop();
            Ev::stop(Ev::BREAK_ALL);
            return;
        }

        if (false === ($buf = socket_read($msgsock, 2048, PHP_NORMAL_READ))) {
            fprintf(STDERR, "socket_read failed: %s\n",
                socket_strerror(socket_last_error()));
            return;
        }

        $buf = trim($buf);

        if ($buf == 'quit') {
            $watcher->stop();
            socket_close($msgsock);
            return;
        }

        $talkback = "You said: $buf\n";
        if (! socket_write($msgsock, $talkback, strlen($talkback))) {
            $errno = socket_last_error();
            fprintf(STDERR, "socket_write failed: %s\n", socket_strerror($errno));

            $watcher->stop();
            socket_close($msgsock);
            echo "Connection closed\n";

            return;
        }
        echo "$buf\n";
    });

    echo "Running Ev loop\n";

    Ev::run();

    if (is_resource($msgsock)) {
        socket_close($msgsock);
    }
} while (true);

socket_close($sock);

[Ruslan Osmanov]

You might want to check if socket_last_error() == SIGPIPE.

[Alex Sky]

Ok, thank.