From 4ab48165563861a9d82a4f7d717e0ec198958294 Mon Sep 17 00:00:00 2001
From: Jakob Borg <jakob@nym.se>
Date: Sat, 21 Jun 2014 09:43:12 +0200
Subject: [PATCH] Detect deadlock in model and panic

---
 Godeps/Godeps.json            |  2 +-
 cmd/syncthing/usage_report.go |  1 +
 model/model.go                |  4 ++++
 model/util.go                 | 26 ++++++++++++++++++++++++++
 4 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/Godeps/Godeps.json b/Godeps/Godeps.json
index 80dac6605..9ad57d438 100644
--- a/Godeps/Godeps.json
+++ b/Godeps/Godeps.json
@@ -1,6 +1,6 @@
 {
 	"ImportPath": "github.com/calmh/syncthing",
-	"GoVersion": "go1.2.2",
+	"GoVersion": "go1.3",
 	"Packages": [
 		"./cmd/syncthing",
 		"./cmd/assets",
diff --git a/cmd/syncthing/usage_report.go b/cmd/syncthing/usage_report.go
index 430f9b8b3..cee7196aa 100644
--- a/cmd/syncthing/usage_report.go
+++ b/cmd/syncthing/usage_report.go
@@ -25,6 +25,7 @@ func reportData(m *model.Model) map[string]interface{} {
 	res := make(map[string]interface{})
 	res["uniqueID"] = strings.ToLower(certID([]byte(myID)))[:6]
 	res["version"] = Version
+	res["longVersion"] = LongVersion
 	res["platform"] = runtime.GOOS + "-" + runtime.GOARCH
 	res["numRepos"] = len(cfg.Repositories)
 	res["numNodes"] = len(cfg.Nodes)
diff --git a/model/model.go b/model/model.go
index c87e5c11b..e0ca693a5 100644
--- a/model/model.go
+++ b/model/model.go
@@ -15,6 +15,7 @@ import (
 	"path/filepath"
 	"sync"
 	"time"
+
 	"github.com/calmh/syncthing/cid"
 	"github.com/calmh/syncthing/config"
 	"github.com/calmh/syncthing/files"
@@ -96,6 +97,9 @@ func NewModel(indexDir string, cfg *config.Configuration, clientName, clientVers
 		sup:           suppressor{threshold: int64(cfg.Options.MaxChangeKbps)},
 	}
 
+	deadlockDetect(&m.rmut, 60*time.Second)
+	deadlockDetect(&m.smut, 60*time.Second)
+	deadlockDetect(&m.pmut, 60*time.Second)
 	go m.broadcastIndexLoop()
 	return m
 }
diff --git a/model/util.go b/model/util.go
index 9445e61e6..35a620d09 100644
--- a/model/util.go
+++ b/model/util.go
@@ -7,6 +7,8 @@ package model
 import (
 	"fmt"
 	"path/filepath"
+	"sync"
+	"time"
 
 	"github.com/calmh/syncthing/protocol"
 	"github.com/calmh/syncthing/scanner"
@@ -90,3 +92,27 @@ func compareClusterConfig(local, remote protocol.ClusterConfigMessage) error {
 
 	return nil
 }
+
+func deadlockDetect(mut sync.Locker, timeout time.Duration) {
+	go func() {
+		for {
+			time.Sleep(timeout / 4)
+			ok := make(chan bool, 2)
+
+			go func() {
+				mut.Lock()
+				mut.Unlock()
+				ok <- true
+			}()
+
+			go func() {
+				time.Sleep(timeout)
+				ok <- false
+			}()
+
+			if r := <-ok; !r {
+				panic("deadlock detected")
+			}
+		}
+	}()
+}