Change order of lock to prevent deadlock. (#368)

FabianSchurig · web-flow · commit 178a6266a31a · 2022-04-27T15:57:36.000+02:00
Resolves #367.
diff --git a/include/behaviortree_cpp_v3/blackboard.h b/include/behaviortree_cpp_v3/blackboard.h
@@ -116,8 +116,8 @@ class Blackboard
     template <typename T>
     void set(const std::string& key, const T& value)
     {
-        std::unique_lock<std::mutex> lock(mutex_);
         std::unique_lock<std::mutex> lock_entry(entry_mutex_);
+        std::unique_lock<std::mutex> lock(mutex_);
         auto it = storage_.find(key);
 
         if( auto parent = parent_bb_.lock())

Original file line number	Diff line number	Diff line change
`@@ -116,8 +116,8 @@ class Blackboard`
`116`	`116`	`template <typename T>`
`117`	`117`	`void set(const std::string& key, const T& value)`
`118`	`118`	`{`
`119`		`- std::unique_lock<std::mutex> lock(mutex_);`
`120`	`119`	`std::unique_lock<std::mutex> lock_entry(entry_mutex_);`
	`120`	`+ std::unique_lock<std::mutex> lock(mutex_);`
`121`	`121`	`auto it = storage_.find(key);`
`122`	`122`
`123`	`123`	`if( auto parent = parent_bb_.lock())`