Return immediately from GetLogLines if logging to memory isn't enabled.

src/log.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 405 matching lines @@
 
   delete mutex_;
   mutex_ = NULL;
 
   DeleteArray(message_buffer_);
   message_buffer_ = NULL;
 }
 
 
 int Log::GetLogLines(int from_pos, char* dest_buf, int max_size) {
+  if (Write != WriteToMemory) return 0;

[Søren Thygesen Gjesse, 2009/05/08 09:59:33]

Maybe we should consider having an enum to indicate to where log output is going
instead of checking the write function.

[Mikhail Naganov, 2009/05/08 10:06:15]

And end up have two variables for specifying mode (Write and the new enum)? No.
I think the current semantics is fine.

   ASSERT(output_.buffer != NULL);
   ASSERT(output_buffer_write_pos_ >= output_.buffer);
   ASSERT(from_pos >= 0);
   ASSERT(max_size >= 0);
   int actual_size = max_size;
   char* buffer_read_pos = output_.buffer + from_pos;
   ScopedLock sl(mutex_);
   if (actual_size == 0
       || output_buffer_write_pos_ == output_.buffer
       || buffer_read_pos >= output_buffer_write_pos_) {
@@ skipping 877 matching lines @@
     } else if (previous_->state_ == EXTERNAL) {
       // We are leaving V8.
       Heap::Protect();
     }
   }
 #endif
 }
 #endif
 
 } }  // namespace v8::internal