1 files changed, 46 insertions, 10 deletions

diff --git a/libbutl/diagnostics.cxx b/libbutl/diagnostics.cxx
index 8525d60..6ac8192 100644
--- a/libbutl/diagnostics.cxx
+++ b/libbutl/diagnostics.cxx
@@ -17,6 +17,14 @@
 #include <cstddef>  // size_t
 #include <iostream> // cerr
 
+#ifndef LIBBUTL_MINGW_STDTHREAD
+#  include <mutex>
+#else
+#  include <libbutl/mingw-mutex.hxx>
+#endif
+
+#include <libbutl/ft/lang.hxx> // thread_local
+
 #include <libbutl/utility.hxx>
 #include <libbutl/optional.hxx>
 #include <libbutl/fdstream.hxx>
@@ -27,7 +35,11 @@ namespace butl
 {
   ostream* diag_stream = &cerr;
 
-  static mutex diag_mutex;
+#ifndef LIBBUTL_MINGW_STDTHREAD
+  static std::mutex diag_mutex;
+#else
+  static mingw_stdthread::mutex diag_mutex;
+#endif
 
   string diag_progress;
   static string diag_progress_blank; // Being printed blanks out the line.
@@ -131,28 +143,28 @@ namespace butl
   default_writer (const diag_record& r)
   {
     r.os.put ('\n');
-    diag_stream_lock () << r.os.str ();
+
+    diag_stream_lock l;
+    (*diag_stream) << r.os.str ();
 
     // We can endup flushing the result of several writes. The last one may
     // possibly be incomplete, but that's not a problem as it will also be
     // followed by the flush() call.
     //
-    // @@ Strange: why not just hold the lock for both write and flush?
-    //
     diag_stream->flush ();
   }
 
-  void (*diag_record::writer) (const diag_record&) = &default_writer;
+  diag_writer* diag_record::writer = &default_writer;
 
   void diag_record::
-  flush () const
+  flush (void (*w) (const diag_record&)) const
   {
     if (!empty_)
     {
       if (epilogue_ == nullptr)
       {
-        if (writer != nullptr)
-          writer (*this);
+        if (w != nullptr || (w = writer) != nullptr)
+          w (*this);
 
         empty_ = true;
       }
@@ -162,8 +174,8 @@ namespace butl
         //
         auto e (epilogue_);
         epilogue_ = nullptr;
-        e (*this); // Can throw.
-        flush ();  // Call ourselves to write the data in case it returns.
+        e (*this, w); // Can throw.
+        flush (w);    // Call ourselves to write the data in case it returns.
       }
     }
   }
@@ -186,4 +198,28 @@ namespace butl
       flush ();
 #endif
   }
+
+  // Diagnostics stack.
+  //
+  static
+#ifdef __cpp_thread_local
+  thread_local
+#else
+  __thread
+#endif
+  const diag_frame* diag_frame_stack = nullptr;
+
+  const diag_frame* diag_frame::
+  stack () noexcept
+  {
+    return diag_frame_stack;
+  }
+
+  const diag_frame* diag_frame::
+  stack (const diag_frame* f) noexcept
+  {
+    const diag_frame* r (diag_frame_stack);
+    diag_frame_stack = f;
+    return r;
+  }
 }