static _Unwind_Reason_Code unwind_phase2_forced(struct _Unwind_Exception* exception_object, _Unwind_Stop_Fn stop, void* stop_parameter) { // walk each frame until we reach where search phase said to stop _Unwind_FunctionContext_t c = __Unwind_SjLj_GetTopOfFunctionStack(); while ( true ) { // get next frame (skip over first which is _Unwind_RaiseException) if ( c == NULL ) { DEBUG_PRINT_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step() reached bottom => _URC_END_OF_STACK\n", exception_object); return _URC_END_OF_STACK; } // call stop function at each frame _Unwind_Action action = (_Unwind_Action)(_UA_FORCE_UNWIND|_UA_CLEANUP_PHASE); _Unwind_Reason_Code stopResult = (*stop)(1, action, exception_object->exception_class, exception_object, (struct _Unwind_Context*)c, stop_parameter); DEBUG_PRINT_UNWINDING("unwind_phase2_forced(ex_ojb=%p): stop function returned %d\n", exception_object, stopResult); if ( stopResult != _URC_NO_REASON ) { DEBUG_PRINT_UNWINDING("unwind_phase2_forced(ex_ojb=%p): stopped by stop function\n", exception_object); return _URC_FATAL_PHASE2_ERROR; } // if there is a personality routine, tell it we are unwinding if ( c->personality != NULL ) { __personality_routine p = (__personality_routine)c->personality; DEBUG_PRINT_UNWINDING("unwind_phase2_forced(ex_ojb=%p): calling personality function %p\n", exception_object, p); _Unwind_Reason_Code personalityResult = (*p)(1, action, exception_object->exception_class, exception_object, (struct _Unwind_Context*)c); switch ( personalityResult ) { case _URC_CONTINUE_UNWIND: DEBUG_PRINT_UNWINDING("unwind_phase2_forced(ex_ojb=%p): personality returned _URC_CONTINUE_UNWIND\n", exception_object); // destructors called, continue unwinding break; case _URC_INSTALL_CONTEXT: DEBUG_PRINT_UNWINDING("unwind_phase2_forced(ex_ojb=%p): personality returned _URC_INSTALL_CONTEXT\n", exception_object); // we may get control back if landing pad calls _Unwind_Resume() __Unwind_SjLj_SetTopOfFunctionStack(c); __builtin_longjmp(c->jbuf, 1); break; default: // something went wrong DEBUG_PRINT_UNWINDING("unwind_phase2_forced(ex_ojb=%p): personality returned %d, _URC_FATAL_PHASE2_ERROR\n", exception_object, personalityResult); return _URC_FATAL_PHASE2_ERROR; } } c = c->prev; } // call stop function one last time and tell it we've reached the end of the stack DEBUG_PRINT_UNWINDING("unwind_phase2_forced(ex_ojb=%p): calling stop function with _UA_END_OF_STACK\n", exception_object); _Unwind_Action lastAction = (_Unwind_Action)(_UA_FORCE_UNWIND|_UA_CLEANUP_PHASE|_UA_END_OF_STACK); (*stop)(1, lastAction, exception_object->exception_class, exception_object, (struct _Unwind_Context*)c, stop_parameter); // clean up phase did not resume at the frame that the search phase said it would return _URC_FATAL_PHASE2_ERROR; }
static _Unwind_Reason_Code unwind_phase2(struct _Unwind_Exception* exception_object) { DEBUG_PRINT_UNWINDING("unwind_phase2(ex_ojb=%p)\n", exception_object); // walk each frame until we reach where search phase said to stop _Unwind_FunctionContext_t c = __Unwind_SjLj_GetTopOfFunctionStack(); while ( true ) { DEBUG_PRINT_UNWINDING("unwind_phase2s(ex_ojb=%p): function-context=%p\n", exception_object, c); // check for no more frames if ( c == NULL ) { DEBUG_PRINT_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step() reached bottom => _URC_END_OF_STACK\n", exception_object); return _URC_END_OF_STACK; } // if there is a personality routine, tell it we are unwinding if ( c->personality != NULL ) { _Unwind_Action action = _UA_CLEANUP_PHASE; if ( (uintptr_t)c == exception_object->private_2 ) action = (_Unwind_Action)(_UA_CLEANUP_PHASE|_UA_HANDLER_FRAME); // tell personality this was the frame it marked in phase 1 _Unwind_Reason_Code personalityResult = (*c->personality)(1, action, exception_object->exception_class, exception_object, (struct _Unwind_Context*)c); switch ( personalityResult ) { case _URC_CONTINUE_UNWIND: // continue unwinding DEBUG_PRINT_UNWINDING("unwind_phase2(ex_ojb=%p): _URC_CONTINUE_UNWIND\n", exception_object); if ( (uintptr_t)c == exception_object->private_2 ) { // phase 1 said we would stop at this frame, but we did not... ABORT("during phase1 personality function said it would stop here, but now if phase2 it did not stop here"); } break; case _URC_INSTALL_CONTEXT: DEBUG_PRINT_UNWINDING("unwind_phase2(ex_ojb=%p): _URC_INSTALL_CONTEXT, will resume at landing pad %p\n", exception_object, c->jbuf[1]); // personality routine says to transfer control to landing pad // we may get control back if landing pad calls _Unwind_Resume() __Unwind_SjLj_SetTopOfFunctionStack(c); __builtin_longjmp(c->jbuf, 1); // unw_resume() only returns if there was an error return _URC_FATAL_PHASE2_ERROR; default: // something went wrong DEBUG_MESSAGE("personality function returned unknown result %d", personalityResult); return _URC_FATAL_PHASE2_ERROR; } } c = c->prev; } // clean up phase did not resume at the frame that the search phase said it would return _URC_FATAL_PHASE2_ERROR; }
/// Called at end of each function that catches exceptions _LIBUNWIND_EXPORT void _Unwind_SjLj_Unregister(struct _Unwind_FunctionContext *fc) { __Unwind_SjLj_SetTopOfFunctionStack(fc->prev); }
/// Called at start of each function that catches exceptions _LIBUNWIND_EXPORT void _Unwind_SjLj_Register(struct _Unwind_FunctionContext *fc) { fc->prev = __Unwind_SjLj_GetTopOfFunctionStack(); __Unwind_SjLj_SetTopOfFunctionStack(fc); }