chore: use signal.NotifyContext over custom implementation (#10311)

Go 1.16 added the signal.NotifyContext helper utility. `installSignals` could be further inlined in a future iteration, if needed.

When reading the [function documentation](https://pkg.go.dev/os/signal#NotifyContext), it becomes clear that this is doing the exact same thing as the old code.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/10311
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: nachtjasmin <nachtjasmin@posteo.de>
Co-committed-by: nachtjasmin <nachtjasmin@posteo.de>

cmd/cmd.go

@@ -1,4 +1,5 @@
 // Copyright 2018 The Gitea Authors. All rights reserved.
+// Copyright 2026 The Forgejo Authors. All rights reserved.
 // SPDX-License-Identifier: MIT
 
 // Package cmd provides subcommands to the gitea binary - such as "web" or
@@ -89,26 +90,9 @@ If this is the intended configuration file complete the [database] section.`, se
 	return nil
 }
 
+// installSignals returns a context that's cancelled on the SIGINT and SIGTERM signals or if the passed ctx is cancelled.
 func installSignals(ctx context.Context) (context.Context, context.CancelFunc) {
-	ctx, cancel := context.WithCancel(ctx)
+	return signal.NotifyContext(ctx, syscall.SIGINT, syscall.SIGTERM)
-	go func() {
-		// install notify
-		signalChannel := make(chan os.Signal, 1)
-
-		signal.Notify(
-			signalChannel,
-			syscall.SIGINT,
-			syscall.SIGTERM,
-		)
-		select {
-		case <-signalChannel:
-		case <-ctx.Done():
-		}
-		cancel()
-		signal.Reset()
-	}()
-
-	return ctx, cancel
 }
 
 func setupConsoleLogger(level log.Level, colorize bool, out io.Writer) {

cmd/cmd_test.go

@@ -0,0 +1,39 @@
+// Copyright 2026 The Forgejo Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"runtime"
+	"syscall"
+	"testing"
+	"time"
+)
+
+func Test_installSignals(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skipf("Windows does not terminate in an awaitable manner")
+		return
+	}
+
+	for _, s := range []syscall.Signal{syscall.SIGTERM, syscall.SIGINT} {
+		t.Run(fmt.Sprintf("Context is terminated on %s", s), func(t *testing.T) {
+			// Register the signal handler. context.Background() is chosen deliberately,
+			// because unlike t.Context(), we can be sure that it's not cancelled by a
+			// different handler.
+			ctx, cancel := installSignals(context.Background())
+			t.Cleanup(cancel)
+
+			// Send the signal in the background.
+			go syscall.Kill(syscall.Getpid(), s)
+
+			select {
+			case <-time.Tick(time.Second * 10):
+				t.Fatalf("Context not cancelled via signal after 10 seconds")
+			case <-ctx.Done():
+				t.Logf("Context was cancelled")
+			}
+		})
+	}
+}