Merge "Only copy mcontext data from sigcontext." (d917d64f) · Commits · e / os / android_system_core

libbacktrace/BacktraceThread.cpp

+7 −1

Original line number	Diff line number	Diff line
		@@ -117,6 +117,12 @@ void ThreadEntry::Wake() {
		futex(&futex_, FUTEX_WAKE, INT_MAX, NULL, NULL, 0);
		}

		void ThreadEntry::CopyUcontextFromSigcontext(void* sigcontext) {
		ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(sigcontext);
		// The only thing the unwinder cares about is the mcontext data.
		memcpy(&ucontext_.uc_mcontext, &ucontext->uc_mcontext, sizeof(ucontext->uc_mcontext));
		}

		//-------------------------------------------------------------------------
		// BacktraceThread functions.
		//-------------------------------------------------------------------------
		@@ -129,7 +135,7 @@ static void SignalHandler(int, siginfo_t, void sigcontext) {
		return;
		}

		entry->CopyUcontext(reinterpret_cast<ucontext_t*>(sigcontext));
		entry->CopyUcontextFromSigcontext(sigcontext);

		// Indicate the ucontext is now valid.
		entry->Wake();

+2 −4

Original line number	Diff line number	Diff line
		@@ -40,14 +40,12 @@ public:

		static void Remove(ThreadEntry* entry);

		inline void CopyUcontext(ucontext_t* ucontext) {
		memcpy(&ucontext_, ucontext, sizeof(ucontext_));
		}

		void Wake();

		void Wait(int);

		void CopyUcontextFromSigcontext(void*);

		inline void Lock() {
		pthread_mutex_lock(&mutex_);
		// Reset the futex value in case of multiple unwinds of the same thread.