Merge pull request #5872 from ipfs/misc/move-intr-handler

 main: move InterruptHandler to util

cmd/ipfs/main.go

@@ -5,17 +5,14 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io"
 	"math/rand"
 	"os"
-	"os/signal"
 	"path/filepath"
 	"runtime/pprof"
 	"strings"
-	"sync"
-	"syscall"
 	"time"
 
+	util "github.com/ipfs/go-ipfs/cmd/ipfs/util"
 	oldcmds "github.com/ipfs/go-ipfs/commands"
 	core "github.com/ipfs/go-ipfs/core"
 	corecmds "github.com/ipfs/go-ipfs/core/commands"
@@ -106,7 +103,7 @@ func mainRet() int {
 	}
 	defer stopFunc() // to be executed as late as possible
 
-	intrh, ctx := setupInterruptHandler(ctx)
+	intrh, ctx := util.SetupInterruptHandler(ctx)
 	defer intrh.Close()
 
 	// Handle `ipfs version` or `ipfs help`
@@ -355,70 +352,6 @@ func writeHeapProfileToFile() error {
 	return pprof.WriteHeapProfile(mprof)
 }
 
-// IntrHandler helps set up an interrupt handler that can
-// be cleanly shut down through the io.Closer interface.
-type IntrHandler struct {
-	sig chan os.Signal
-	wg  sync.WaitGroup
-}
-
-func NewIntrHandler() *IntrHandler {
-	ih := &IntrHandler{}
-	ih.sig = make(chan os.Signal, 1)
-	return ih
-}
-
-func (ih *IntrHandler) Close() error {
-	close(ih.sig)
-	ih.wg.Wait()
-	return nil
-}
-
-// Handle starts handling the given signals, and will call the handler
-// callback function each time a signal is catched. The function is passed
-// the number of times the handler has been triggered in total, as
-// well as the handler itself, so that the handling logic can use the
-// handler's wait group to ensure clean shutdown when Close() is called.
-func (ih *IntrHandler) Handle(handler func(count int, ih *IntrHandler), sigs ...os.Signal) {
-	signal.Notify(ih.sig, sigs...)
-	ih.wg.Add(1)
-	go func() {
-		defer ih.wg.Done()
-		count := 0
-		for range ih.sig {
-			count++
-			handler(count, ih)
-		}
-		signal.Stop(ih.sig)
-	}()
-}
-
-func setupInterruptHandler(ctx context.Context) (io.Closer, context.Context) {
-	intrh := NewIntrHandler()
-	ctx, cancelFunc := context.WithCancel(ctx)
-
-	handlerFunc := func(count int, ih *IntrHandler) {
-		switch count {
-		case 1:
-			fmt.Println() // Prevent un-terminated ^C character in terminal
-
-			ih.wg.Add(1)
-			go func() {
-				defer ih.wg.Done()
-				cancelFunc()
-			}()
-
-		default:
-			fmt.Println("Received another interrupt before graceful shutdown, terminating...")
-			os.Exit(-1)
-		}
-	}
-
-	intrh.Handle(handlerFunc, syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM)
-
-	return intrh, ctx
-}
-
 func profileIfEnabled() (func(), error) {
 	// FIXME this is a temporary hack so profiling of asynchronous operations
 	// works as intended.

cmd/ipfs/util/signal.go

@@ -0,0 +1,77 @@
+// +build !wasm
+
+package util
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"os/signal"
+	"sync"
+	"syscall"
+)
+
+// IntrHandler helps set up an interrupt handler that can
+// be cleanly shut down through the io.Closer interface.
+type IntrHandler struct {
+	sig chan os.Signal
+	wg  sync.WaitGroup
+}
+
+func NewIntrHandler() *IntrHandler {
+	ih := &IntrHandler{}
+	ih.sig = make(chan os.Signal, 1)
+	return ih
+}
+
+func (ih *IntrHandler) Close() error {
+	close(ih.sig)
+	ih.wg.Wait()
+	return nil
+}
+
+// Handle starts handling the given signals, and will call the handler
+// callback function each time a signal is catched. The function is passed
+// the number of times the handler has been triggered in total, as
+// well as the handler itself, so that the handling logic can use the
+// handler's wait group to ensure clean shutdown when Close() is called.
+func (ih *IntrHandler) Handle(handler func(count int, ih *IntrHandler), sigs ...os.Signal) {
+	signal.Notify(ih.sig, sigs...)
+	ih.wg.Add(1)
+	go func() {
+		defer ih.wg.Done()
+		count := 0
+		for range ih.sig {
+			count++
+			handler(count, ih)
+		}
+		signal.Stop(ih.sig)
+	}()
+}
+
+func SetupInterruptHandler(ctx context.Context) (io.Closer, context.Context) {
+	intrh := NewIntrHandler()
+	ctx, cancelFunc := context.WithCancel(ctx)
+
+	handlerFunc := func(count int, ih *IntrHandler) {
+		switch count {
+		case 1:
+			fmt.Println() // Prevent un-terminated ^C character in terminal
+
+			ih.wg.Add(1)
+			go func() {
+				defer ih.wg.Done()
+				cancelFunc()
+			}()
+
+		default:
+			fmt.Println("Received another interrupt before graceful shutdown, terminating...")
+			os.Exit(-1)
+		}
+	}
+
+	intrh.Handle(handlerFunc, syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM)
+
+	return intrh, ctx
+}

cmd/ipfs/util/signal_wasm.go

@@ -0,0 +1,18 @@
+package util
+
+import (
+	"context"
+	"io"
+)
+
+type ctxCloser context.CancelFunc
+
+func (c ctxCloser) Close() error {
+	c()
+	return nil
+}
+
+func SetupInterruptHandler(ctx context.Context) (io.Closer, context.Context) {
+	ctx, cancel := context.WithCancel(ctx)
+	return ctxCloser(cancel), ctx
+}