我是套接字的新手,正在尝试通过GJS/Gio中的一些套接字编程工作,碰壁创建了GLib.Source来处理从套接字接收消息。相关代码(我认为)是:
const DeviceChannel = new Lang.Class({
Name: "DeviceChannel",
_init: function (device) {
this.device = device;
this.connection = null;
this.inStream = null;
this.outStream = null;
this.socket = null;
this.sock_source = 0;
},
open: function () {
let client = new Gio.SocketClient();
this.addr = new Gio.InetSocketAddress({
address: this.device.tcpHost,
port: this.device.tcpPort
});
let conn = client.connect_async(
this.addr,
null,
Lang.bind(this, this.opened)
);
},
opened: function (client, res) {
this.connection = client.connect_finish(res);
// Streams
this.inStream = new Gio.DataInputStream({
base_stream: this.connection.get_input_stream()
});
this.outStream = new Gio.DataOutputStream({
base_stream: this.connection.get_output_stream()
});
// Socket
this.socket = this.connection.get_socket();
this.socket.set_option(6, 4, 10); // TCP_KEEPIDLE
this.socket.set_option(6, 5, 5); // TCP_KEEPINTVL
this.socket.set_option(6, 6, 3); // TCP_KEEPCNT
this.socket.set_keepalive(true);
this.sock_source = this.socket.create_source(GLib.IOCondition.IN, null);
this.sock_source.set_callback(Lang.bind(this, this._io_ready));
this.sock_source.attach(null);
},
_io_ready: function (condition) {
return true;
}
});
一切顺利,直到出现错误时我调用
this.sock_source.set_callback()
为止:(JSConnect:15118): Gjs-WARNING **: JS ERROR: TypeError: this.sock_source is null
DeviceChannel<.opened@application.js:184:9
wrapper@resource:///org/gnome/gjs/modules/lang.js:178:22
@application.js:427:2
我在代码正常工作的另一部分中的另一个套接字(尽管是UDP)上调用了
Gio.Socket.create_source()
。调用create_source()
本身不会引发任何错误(即使我使用G_MESSAGES_DEBUG=all
运行我的脚本),并且也没有提到该函数曾经返回null
in the documentation,因此我对自己的错误感到困惑。编辑:
有3岁的注释here指出:
This does not work since 1) Socket.create_source doesn't exist in typelib as it is marked with (skip) in Glib/gio/gsocket.c
但是我认为这不再正确,因为我已经在UDP套接字上创建了一个源,尽管该套接字是“手工制作的”,而不是使用
Gio.SocketClient()
构建的。
最佳答案
您可能无意中调用了 Gio.DatagramBased.create_source()
方法。查看源代码,这最终将调用g_socket_create_source()
,但首先进行一些检查,如果失败则返回null
。这是检查:https://github.com/GNOME/glib/blob/master/gio/gsocket.c#L1114
看来the method will simply return null
是一个小错误,甚至没有从check_datagram_based()
打印错误。
关于sockets - 为什么Gio.Socket.create_source()返回null?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/46111145/