From f4021f0c68b680e1b2a1fc027e81a54c700dd245 Mon Sep 17 00:00:00 2001
From: mmentovai <mmentovai@4c0a9323-5329-0410-9bdc-e9ce6186880e>
Date: Thu, 18 Oct 2007 20:54:20 +0000
Subject: [PATCH] Make Breakpad's debug-exception-ignoring configurable. 
 r=Nicolas Sylvain

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@224 4c0a9323-5329-0410-9bdc-e9ce6186880e
---
 src/client/windows/handler/exception_handler.cc | 10 +++++++---
 src/client/windows/handler/exception_handler.h  | 11 +++++++++++
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/src/client/windows/handler/exception_handler.cc b/src/client/windows/handler/exception_handler.cc
index 4bb67b21..0e6c43c9 100644
--- a/src/client/windows/handler/exception_handler.cc
+++ b/src/client/windows/handler/exception_handler.cc
@@ -72,7 +72,8 @@ ExceptionHandler::ExceptionHandler(const wstring &dump_path,
       requesting_thread_id_(0),
       exception_info_(NULL),
       assertion_(NULL),
-      handler_return_value_(false) {
+      handler_return_value_(false),
+      handle_debug_exceptions_(false) {
 #if _MSC_VER >= 1400  // MSVC 2005/8
   previous_iph_ = NULL;
 #endif  // _MSC_VER >= 1400
@@ -274,10 +275,13 @@ LONG ExceptionHandler::HandleException(EXCEPTION_POINTERS *exinfo) {
   // Ignore EXCEPTION_BREAKPOINT and EXCEPTION_SINGLE_STEP exceptions.  This
   // logic will short-circuit before calling WriteMinidumpOnHandlerThread,
   // allowing something else to handle the breakpoint without incurring the
-  // overhead transitioning to and from the handler thread.
+  // overhead transitioning to and from the handler thread.  This behavior
+  // can be overridden by calling ExceptionHandler::set_handle_debug_exceptions.
   DWORD code = exinfo->ExceptionRecord->ExceptionCode;
   LONG action;
-  if (code != EXCEPTION_BREAKPOINT && code != EXCEPTION_SINGLE_STEP &&
+  bool is_debug_exception = (code == EXCEPTION_BREAKPOINT) ||
+                            (code == EXCEPTION_SINGLE_STEP);
+  if ((!is_debug_exception || current_handler->get_handle_debug_exceptions()) &&
       current_handler->WriteMinidumpOnHandlerThread(exinfo, NULL)) {
     // The handler fully handled the exception.  Returning
     // EXCEPTION_EXECUTE_HANDLER indicates this to the system, and usually
diff --git a/src/client/windows/handler/exception_handler.h b/src/client/windows/handler/exception_handler.h
index 433b6bf4..7d82564c 100644
--- a/src/client/windows/handler/exception_handler.h
+++ b/src/client/windows/handler/exception_handler.h
@@ -175,6 +175,12 @@ class ExceptionHandler {
   // dumps.
   DWORD get_requesting_thread_id() const { return requesting_thread_id_; }
 
+  // Controls behavior of EXCEPTION_BREAKPOINT and EXCEPTION_SINGLE_STEP.
+  bool get_handle_debug_exceptions() const { return handle_debug_exceptions_; }
+  void set_handle_debug_exceptions(bool handle_debug_exceptions) {
+    handle_debug_exceptions_ = handle_debug_exceptions;
+  }
+
  private:
   friend class AutoExceptionHandler;
 
@@ -322,6 +328,11 @@ class ExceptionHandler {
   // the requesting thread.
   bool handler_return_value_;
 
+  // If true, the handler will intercept EXCEPTION_BREAKPOINT and
+  // EXCEPTION_SINGLE_STEP exceptions.  Leave this false (the default)
+  // to not interfere with debuggers.
+  bool handle_debug_exceptions_;
+
   // A stack of ExceptionHandler objects that have installed unhandled
   // exception filters.  This vector is used by HandleException to determine
   // which ExceptionHandler object to route an exception to.  When an