Fix #9854.

The post syscall debug events used for output capture have an unfortunate side effect: when asked to debug a thread, the thread is interrupted, which, if currently blocked in a syscall will cause it to unblock and send a post syscall event indicating such. However, this will also absorb the debug stop flag that was set by the initial debug request, and so we won't actually get the separate event indicating thread debugged. Consequently, we now set a pending stop request flag on the corresponding Thread object, and check if it's set when processing syscall events. If so, we treat such an event as having triggered a debug stop even though the received event type is not explicitly B_DEBUGGER_MESSAGE_THREAD_DEBUGGED.
2013-07-04 07:39:42 -04:00
parent cc6b4a3cb1
commit 3c26fbf06b
2 changed files with 15 additions and 2 deletions
@@ -1270,6 +1270,18 @@ TeamDebugger::_HandleDebuggerMessage(DebugEvent* event)
 			TRACE_EVENTS("B_DEBUGGER_MESSAGE_POST_SYSCALL: syscall: %"
 				B_PRIu32 "\n", postSyscallEvent->GetSyscallInfo().Syscall());
 			handled = _HandlePostSyscall(postSyscallEvent);
+
+			// if a thread was blocked in a syscall when we requested to
+			// stop it for debugging, then that request will interrupt
+			// said call, and the post syscall event will be all we get
+			// in response. Consequently, we need to treat this case as
+			// equivalent to having received a thread debugged event.
+			AutoLocker< ::Team> teamLocker(fTeam);
+			::Thread* thread = fTeam->ThreadByID(event->Thread());
+			if (handler != NULL && thread != NULL
+				&& thread->StopRequestPending()) {
+				handled = handler->HandleThreadDebugged(NULL);
+			}
 			break;
 		}
 		case B_DEBUGGER_MESSAGE_PRE_SYSCALL: