From 618a6acd592f98e770f104021273bfa95c8e893e Mon Sep 17 00:00:00 2001
From: Strahinja Val Markovic <val@markovic.io>
Date: Wed, 1 Aug 2012 20:09:01 -0700
Subject: [PATCH] Protecting ALL clang access with a mutex now

---
 cpp/ycm/ClangCompleter.cpp | 18 +++++++++++++-----
 cpp/ycm/ClangCompleter.h   |  5 +++++
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/cpp/ycm/ClangCompleter.cpp b/cpp/ycm/ClangCompleter.cpp
index d483d3d6..26350d11 100644
--- a/cpp/ycm/ClangCompleter.cpp
+++ b/cpp/ycm/ClangCompleter.cpp
@@ -41,6 +41,7 @@ using boost::lock_guard;
 using boost::unique_lock;
 using boost::mutex;
 using boost::unordered_map;
+using boost::try_to_lock_t;
 
 namespace YouCompleteMe
 {
@@ -326,7 +327,7 @@ std::vector< Diagnostic > ClangCompleter::DiagnosticsForFile(
     const std::string &filename )
 {
   std::vector< Diagnostic > diagnostics;
-  unique_lock< mutex > lock( file_parse_task_mutex_, boost::try_to_lock_t );
+  unique_lock< mutex > lock( clang_access_mutex_, try_to_lock_t() );
   if ( !lock.owns_lock() )
     return diagnostics;
 
@@ -354,8 +355,8 @@ std::vector< Diagnostic > ClangCompleter::DiagnosticsForFile(
 
 bool ClangCompleter::UpdatingTranslationUnit()
 {
-  lock_guard< mutex > lock( file_parse_task_mutex_ );
-  return bool( file_parse_task_ );
+  unique_lock< mutex > lock( clang_access_mutex_, try_to_lock_t() );
+  return !lock.owns_lock();
 }
 
 
@@ -651,7 +652,10 @@ void ClangCompleter::FileParseThreadMain()
       }
     }
 
-    ( *file_parse_task_ )();
+    {
+      unique_lock< mutex > lock( clang_access_mutex_ );
+      ( *file_parse_task_ )();
+    }
 
     lock_guard< mutex > lock( file_parse_task_mutex_ );
     file_parse_task_ = VoidTask();
@@ -675,7 +679,11 @@ void ClangCompleter::ClangCompletionsThreadMain()
         continue;
     }
 
-    ( *task )();
+    {
+      unique_lock< mutex > lock( clang_access_mutex_ );
+      ( *task )();
+    }
+
     unique_future< AsyncCompletions > future = task->get_future();
 
     {
diff --git a/cpp/ycm/ClangCompleter.h b/cpp/ycm/ClangCompleter.h
index 5c8f412b..5848ffed 100644
--- a/cpp/ycm/ClangCompleter.h
+++ b/cpp/ycm/ClangCompleter.h
@@ -132,6 +132,11 @@ private:
 
   mutable LatestTask sorting_task_;
 
+  // TODO: wrap the entire clang API with an internal class that then uses this
+  // mutex... actually a TU class with an internal mutex
+  // Only the thread that is holding this mutex can access clang functions
+  boost::mutex clang_access_mutex_;
+
   // Only the clang thread can make this NULL and only the GUI thread can make
   // it non-NULL. The file_parse_task_mutex_ is used before checking the state
   // of NULL. [ NULL for a shared_ptr naturally means default-constructed