Prototype of fix for mac FTDI crash where the entire trace is read even if there is an error (e.g.,…

tools/battor_agent/battor_agent.h

Index: tools/battor_agent/battor_agent.h
diff --git a/tools/battor_agent/battor_agent.h b/tools/battor_agent/battor_agent.h
index 810df26936af2cf15d4c72845937aa7fac8da676..7854790f0538636229f58f2fc0a2cacc7d39d8a4 100644
--- a/tools/battor_agent/battor_agent.h
+++ b/tools/battor_agent/battor_agent.h
@@ -175,12 +175,15 @@ class BattOrAgent : public BattOrConnection::Listener,
   // The number of times we've attempted to init the BattOr.
   uint8_t num_init_attempts_;
 
-  // The number of times that we've attempted to read the last message.
-  uint8_t num_read_attempts_;
-
   // The timeout that's run when an action times out.
   base::CancelableClosure timeout_callback_;
 
+  // First error that was encountered while reading frames. It is necessary
+  // to handle read errors at the end of the read because the FTDI serial
+  // device crashes on OSX if there is data that arrives in the FTDI device's
+  // buffer after the file descriptor is closed.
+  BattOrError read_frame_error_;
+
   DISALLOW_COPY_AND_ASSIGN(BattOrAgent);
 };