MemoryLocationsCollector::collectRealCallStackOnMemoryLimitViolation()

Size

Total Lines	88
Code Lines	56

Duplication

Lines	0
Ratio	0 %

Importance

Changes

0

<?php
    public function collectRealCallStackOnMemoryLimitViolation(
        UserFunctionDefinitionContext $memory_limit_error_function_context,
        int $max_challenge_depth,
        CallFramesContext $call_frames_context,
        ZendExecutorGlobals $eg,
        int $map_ptr_base,
        Dereferencer $dereferencer,
        ZendTypeReader $zend_type_reader,
        MemoryLocations $memory_locations,
        ContextPools $context_pools,
    ): CallFramesContext {
        $op_array_address = $memory_limit_error_function_context->getOpArrayAddress();

        if (is_null($eg->vm_stack)) {
            return $call_frames_context;
        }
        if (is_null($eg->vm_stack_top)) {
            return $call_frames_context;
        }

        $last_vm_stack = $dereferencer->deref($eg->vm_stack);
        $root_vm_stack = $last_vm_stack->getRootStack($dereferencer);
        if (is_null($root_vm_stack->top)) {
            return $call_frames_context;
        }

        $first_stack = true;
        foreach ($last_vm_stack->iterateStackChain($dereferencer) as $vm_stack) {
            if ($first_stack) {
                $first_stack = false;
                $stack_end_address = $eg->vm_stack_top->address;
            } else {
                if (is_null($vm_stack->end)) {
                    break;
                }
                $stack_end_address = $vm_stack->end->address;
            }
            $materialized_vm_stack = $vm_stack->materializeAsPointerArray(
                $dereferencer,
                $stack_end_address
            );
            foreach ($materialized_vm_stack->getReverseIteratorAsInt() as $key => $value) {
                if ($value !== $op_array_address) {
                    continue;
                }
                $pointer_address = $key * 8 + $materialized_vm_stack->getPointer()->address - 24;
                Log::debug('candidate frame found', ['frame_address' => $pointer_address]);
                $frame_candidate = new Pointer(
                    ZendExecuteData::class,
                    $pointer_address,
                    $zend_type_reader->sizeOf('zend_execute_data')
                );
                try {
                    $execute_data_candidate = $dereferencer->deref($frame_candidate);
                    $root_execute_data_candidate = $execute_data_candidate->getRootFrame(
                        $dereferencer,
                        $max_challenge_depth,
                    );
                    if ($root_vm_stack->top->address !== $root_execute_data_candidate->getPointer()->address) {
                        continue;
                    }
                    Log::debug('root candidate frame found', ['frame_address' => $root_vm_stack->top->address]);
                    $frame_start = count($call_frames_context->getLinks());
                    foreach ($execute_data_candidate->iterateStackChain($dereferencer) as $frame_no => $execute_data) {
                        $call_frame_context = $this->collectCallFrame(
                            $execute_data,
                            $map_ptr_base,
                            $dereferencer,
                            $zend_type_reader,
                            $memory_locations,
                            $context_pools,
                        );
                        $call_frames_context->add((string)($frame_no + $frame_start), $call_frame_context);
                    }
                    return $call_frames_context;
                } catch (\Throwable $e) {
                    Log::debug(
                        'failed to collect real call stack from this candidate',
                        [
                            'exception' => $e,
                            'frame_address' => $pointer_address
                        ]
                    );
                    continue;
                }
            }
        }
        return $call_frames_context;
    }