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Diffstat (limited to 'third_party/abseil-cpp/absl/debugging/internal/stacktrace_emscripten-inl.inc')
| -rw-r--r-- | third_party/abseil-cpp/absl/debugging/internal/stacktrace_emscripten-inl.inc | 110 |
1 files changed, 0 insertions, 110 deletions
diff --git a/third_party/abseil-cpp/absl/debugging/internal/stacktrace_emscripten-inl.inc b/third_party/abseil-cpp/absl/debugging/internal/stacktrace_emscripten-inl.inc deleted file mode 100644 index 0f44451438..0000000000 --- a/third_party/abseil-cpp/absl/debugging/internal/stacktrace_emscripten-inl.inc +++ /dev/null @@ -1,110 +0,0 @@ -// Copyright 2017 The Abseil Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// https://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. -// -// Portable implementation - just use glibc -// -// Note: The glibc implementation may cause a call to malloc. -// This can cause a deadlock in HeapProfiler. - -#ifndef ABSL_DEBUGGING_INTERNAL_STACKTRACE_EMSCRIPTEN_INL_H_ -#define ABSL_DEBUGGING_INTERNAL_STACKTRACE_EMSCRIPTEN_INL_H_ - -#include <emscripten.h> - -#include <atomic> -#include <cstring> - -#include "absl/base/attributes.h" -#include "absl/debugging/stacktrace.h" - -extern "C" { -uintptr_t emscripten_stack_snapshot(); -uint32_t emscripten_stack_unwind_buffer(uintptr_t pc, void *buffer, - uint32_t depth); -} - -// Sometimes, we can try to get a stack trace from within a stack -// trace, which can cause a self-deadlock. -// Protect against such reentrant call by failing to get a stack trace. -// -// We use __thread here because the code here is extremely low level -- it is -// called while collecting stack traces from within malloc and mmap, and thus -// can not call anything which might call malloc or mmap itself. -static __thread int recursive = 0; - -// The stack trace function might be invoked very early in the program's -// execution (e.g. from the very first malloc). -// As such, we suppress usage of backtrace during this early stage of execution. -static std::atomic<bool> disable_stacktraces(true); // Disabled until healthy. -// Waiting until static initializers run seems to be late enough. -// This file is included into stacktrace.cc so this will only run once. -ABSL_ATTRIBUTE_UNUSED static int stacktraces_enabler = []() { - // Check if we can even create stacktraces. If not, bail early and leave - // disable_stacktraces set as-is. - // clang-format off - if (!EM_ASM_INT({ return (typeof wasmOffsetConverter !== 'undefined'); })) { - return 0; - } - // clang-format on - disable_stacktraces.store(false, std::memory_order_relaxed); - return 0; -}(); - -template <bool IS_STACK_FRAMES, bool IS_WITH_CONTEXT> -static int UnwindImpl(void **result, int *sizes, int max_depth, int skip_count, - const void *ucp, int *min_dropped_frames) { - if (recursive || disable_stacktraces.load(std::memory_order_relaxed)) { - return 0; - } - ++recursive; - - static_cast<void>(ucp); // Unused. - constexpr int kStackLength = 64; - void *stack[kStackLength]; - - int size; - uintptr_t pc = emscripten_stack_snapshot(); - size = emscripten_stack_unwind_buffer(pc, stack, kStackLength); - - int result_count = size - skip_count; - if (result_count < 0) result_count = 0; - if (result_count > max_depth) result_count = max_depth; - for (int i = 0; i < result_count; i++) result[i] = stack[i + skip_count]; - - if (IS_STACK_FRAMES) { - // No implementation for finding out the stack frame sizes yet. - memset(sizes, 0, sizeof(*sizes) * result_count); - } - if (min_dropped_frames != nullptr) { - if (size - skip_count - max_depth > 0) { - *min_dropped_frames = size - skip_count - max_depth; - } else { - *min_dropped_frames = 0; - } - } - - --recursive; - - return result_count; -} - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace debugging_internal { -bool StackTraceWorksForTest() { return true; } -} // namespace debugging_internal -ABSL_NAMESPACE_END -} // namespace absl - -#endif // ABSL_DEBUGGING_INTERNAL_STACKTRACE_EMSCRIPTEN_INL_H_ |