当ctrl+c发生时如何优雅地退出D程序？

Question

我想通过停止事件循环来优雅地关闭vibe.d应用程序。

import vibe.vibe;
import core.sys.posix.signal;

void main()
{
  enum SIGINT = 2;
  signal(SIGINT, &stopapp);

  auto settings = new HTTPServerSettings;
  settings.port = 8080;
  settings.bindAddresses = ["::1", "127.0.0.1"];
  listenHTTP(settings, &hello);

  logInfo("Please open http://127.0.0.1:8080/ in your browser.");
  runApplication();

}

void hello(HTTPServerRequest req, HTTPServerResponse res)
{
  res.writeBody("Hello, World!");
}

void stopapp(int value){
  logInfo("Stopping app...");
  exitEventLoop();
}

不幸的是，这不起作用：

source/app.d(7,9): Error: function core.stdc.signal.signal(int sig, extern (C) void function(int) nothrow @nogc @system func) is not callable using argument types (int, void function(int value))
source/app.d(7,9):        cannot pass argument & stopapp of type void function(int value) to parameter extern (C) void function(int) nothrow @nogc @system func
dmd failed with exit code 1.

有一个简单的库可以做到这一点吗？

Answer 1

signal

是一个 C 函数。对于 C 函数调用 D 函数，D 函数应标记为

extern(C) signalHandler()

。

import  std.stdio;

extern(C) void signal(int sig, void function(int) );

// Our handler, callable by C
extern(C) void handle(int sig) {
    writeln("Signal:",sig);
}

void main()
{
    enum SIGINT = 2; // OS-specific

    signal(SIGINT,&handle);
    writeln("Hello!");
    readln();
    writeln("End!");
}

对于您的 vivi.d 示例，vib.d 自行处理 SIGINT。这应该有效：

import vibe.vibe;

void main()
{
    auto settings = new HTTPServerSettings;
    settings.port = 8080;
    settings.bindAddresses = ["::1", "127.0.0.1"];
    listenHTTP(settings, &hello);

    logInfo("Please open http://127.0.0.1:8080/ in your browser.");
    runApplication();
}

void hello(HTTPServerRequest req, HTTPServerResponse res)
{
    res.writeBody("Hello, World!");
}

运行此程序并按 C-c。

09:21:59 ~/code/d/stackoverflow/q1
$ ./q1
[main(----) INF] Listening for requests on http://[::1]:8080/
[main(----) INF] Listening for requests on http://127.0.0.1:8080/
[main(----) INF] Please open http://127.0.0.1:8080/ in your browser.
^C[main(----) INF] Received signal 2. Shutting down.
Warning (thread: main): leaking eventcore driver because there are still active handles
FD 6 (streamListen)
FD 7 (streamListen)
Warning (thread: main): leaking eventcore driver because there are still active handles
FD 6 (streamListen)
FD 7 (streamListen)
09:22:04 ~/code/d/stackoverflow/q1
$

Answer 2

而不是

    listenHTTP(settings, &hello);

使用

    auto listener = listenHTTP(settings, &hello);
    scope(exit) {listener.stopListening;}