pkg/tool: add ServeHTTP function

Dedup code in syz-ci and syz-hub.

Author: dvyukov

pkg/tool/tool.go

@@ -7,6 +7,9 @@ package tool
 import (
 	"flag"
 	"fmt"
+	"log"
+	"net"
+	"net/http"
 	"os"
 )
 
@@ -25,6 +28,20 @@ func Init() func() {
 	return installProfiling(*flagCPUProfile, *flagMEMProfile)
 }
 
+// ServeHTPP serves default http mux on the specified address in a separate goroutine.
+// Terminates the process on any errors.
+func ServeHTTP(addr string) {
+	ln, err := net.Listen("tcp4", addr)
+	if err != nil {
+		log.Fatalf("failed to listen on %v: %v", addr, err)
+	}
+	log.Printf("serving http on http://%v", ln.Addr())
+	go func() {
+		err := http.Serve(ln, nil)
+		log.Fatalf("failed to serve http: %v", err)
+	}()
+}
+
 func Failf(msg string, args ...any) {
 	fmt.Fprintf(os.Stderr, msg+"\n", args...)
 	os.Exit(1)

syz-ci/syz-ci.go

@@ -57,7 +57,6 @@ import (
 	"errors"
 	"flag"
 	"fmt"
-	"net"
 	"net/http"
 	_ "net/http/pprof"
 	"os"
@@ -72,6 +71,7 @@ import (
 	"github.com/google/syzkaller/pkg/log"
 	"github.com/google/syzkaller/pkg/mgrconfig"
 	"github.com/google/syzkaller/pkg/osutil"
+	"github.com/google/syzkaller/pkg/tool"
 	"github.com/google/syzkaller/pkg/updater"
 	"github.com/google/syzkaller/pkg/vcs"
 )
@@ -265,7 +265,7 @@ func main() {
 	shutdownPending := make(chan struct{})
 	osutil.HandleInterrupts(shutdownPending)
 
-	serveHTTP(cfg)
+	tool.ServeHTTP(cfg.HTTP)
 
 	if cfg.Goroot != "" {
 		os.Setenv("GOROOT", cfg.Goroot)
@@ -396,18 +396,6 @@ loop:
 	}
 }
 
-func serveHTTP(cfg *Config) {
-	ln, err := net.Listen("tcp4", cfg.HTTP)
-	if err != nil {
-		log.Fatalf("failed to listen on %v: %v", cfg.HTTP, err)
-	}
-	log.Logf(0, "serving http on http://%v", ln.Addr())
-	go func() {
-		err := http.Serve(ln, nil)
-		log.Fatalf("failed to serve http: %v", err)
-	}()
-}
-
 func uploadSyzkallerBuildError(cfg *Config, commit *vcs.Commit, compilerID string, buildErr error) {
 	var output []byte
 	var verbose *osutil.VerboseError

syz-hub/http.go

@@ -6,28 +6,13 @@ package main
 import (
 	"fmt"
 	"html/template"
-	"net"
 	"net/http"
 	"sort"
 	"strings"
 
 	"github.com/google/syzkaller/pkg/log"
 )
 
-func (hub *Hub) initHTTP(addr string) {
-	http.HandleFunc("/", hub.httpSummary)
-
-	ln, err := net.Listen("tcp4", addr)
-	if err != nil {
-		log.Fatalf("failed to listen on %v: %v", addr, err)
-	}
-	log.Logf(0, "serving http on http://%v", ln.Addr())
-	go func() {
-		err := http.Serve(ln, nil)
-		log.Fatalf("failed to serve http: %v", err)
-	}()
-}
-
 func (hub *Hub) httpSummary(w http.ResponseWriter, r *http.Request) {
 	hub.mu.Lock()
 	defer hub.mu.Unlock()

syz-hub/hub.go

@@ -6,6 +6,7 @@ package main
 import (
 	"flag"
 	"fmt"
+	"net/http"
 	"strings"
 	"sync"
 	"time"
@@ -14,6 +15,7 @@ import (
 	"github.com/google/syzkaller/pkg/config"
 	"github.com/google/syzkaller/pkg/log"
 	"github.com/google/syzkaller/pkg/rpctype"
+	"github.com/google/syzkaller/pkg/tool"
 	"github.com/google/syzkaller/syz-hub/state"
 )
 
@@ -59,7 +61,8 @@ func main() {
 		hub.keys[mgr.Name] = mgr.Key
 	}
 
-	hub.initHTTP(cfg.HTTP)
+	http.HandleFunc("/", hub.httpSummary)
+	tool.ServeHTTP(cfg.HTTP)
 	go hub.purgeOldManagers()
 
 	s, err := rpctype.NewRPCServer(cfg.RPC, "Hub", hub)