From 75797c33c3cfd3b3b27b434521972f53fd2f12a6 Mon Sep 17 00:00:00 2001
From: Cedric Beust <cedric@beust.com>
Date: Wed, 3 Aug 2016 19:16:40 -0800
Subject: [PATCH] Better synchronization for the incremental manager.

---
 .../com/beust/kobalt/internal/IncrementalManager.kt  | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/internal/IncrementalManager.kt b/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/internal/IncrementalManager.kt
index d44a6752..09214fc0 100644
--- a/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/internal/IncrementalManager.kt
+++ b/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/internal/IncrementalManager.kt
@@ -72,17 +72,23 @@ class IncrementalManager @Inject constructor(val args: Args, @Assisted val fileN
     }
 
     fun inputChecksumFor(taskName: String) : String? =
+        synchronized(BUILD_INFO_FILE) {
             taskInfoFor(taskInfos(), taskName).inputChecksum
+        }
 
     fun saveOutputChecksum(taskName: String, outputChecksum: String) {
-        with(taskInfos()) {
-            taskInfoFor(this, taskName).outputChecksum = outputChecksum
-            save(this)
+        synchronized(BUILD_INFO_FILE) {
+            with(taskInfos()) {
+                taskInfoFor(this, taskName).outputChecksum = outputChecksum
+                save(this)
+            }
         }
     }
 
     fun outputChecksumFor(taskName: String) : String? =
+        synchronized(BUILD_INFO_FILE) {
             taskInfoFor(taskInfos(), taskName).outputChecksum
+        }
 
     /**
      * @param method is assumed to return an IncrementalTaskInfo.