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-rw-r--r--absl/debugging/internal/stacktrace_libunwind-inl.inc128
1 files changed, 0 insertions, 128 deletions
diff --git a/absl/debugging/internal/stacktrace_libunwind-inl.inc b/absl/debugging/internal/stacktrace_libunwind-inl.inc
deleted file mode 100644
index e9c2d26..0000000
--- a/absl/debugging/internal/stacktrace_libunwind-inl.inc
+++ /dev/null
@@ -1,128 +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
-//
-// http://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.
-
-#ifndef ABSL_DEBUGGING_INTERNAL_STACKTRACE_LIBUNWIND_INL_H_
-#define ABSL_DEBUGGING_INTERNAL_STACKTRACE_LIBUNWIND_INL_H_
-
-// We only need local unwinder.
-#define UNW_LOCAL_ONLY
-
-extern "C" {
-#include "third_party/libunwind/include/libunwind.h"
-}
-#include "absl/debugging/stacktrace.h"
-
-#include "absl/base/dynamic_annotations.h"
-#include "absl/base/internal/raw_logging.h"
-
-// Sometimes, we can try to get a stack trace from within a stack
-// trace, because we don't block signals inside libunwind (which would be too
-// expensive: the two extra system calls per stack trace do matter here).
-// That can cause a self-deadlock (as in http://b/5722312).
-// 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.
-// In particular, using PerThread or STATIC_THREAD_LOCAL_POD
-// here will cause infinite recursion for at least dbg/piii builds with
-// crosstool-v12.
-static __thread int recursive;
-
-template <bool IS_STACK_FRAMES, bool IS_WITH_CONTEXT>
-static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
- const void *, int *min_dropped_frames) {
- if (recursive) {
- return 0;
- }
- ++recursive;
-
- int n = 0;
- if (IS_STACK_FRAMES) {
- void *ip;
- unw_cursor_t cursor;
- unw_context_t uc;
- unw_word_t sp = 0, next_sp = 0;
-
- unw_getcontext(&uc);
- ABSL_RAW_CHECK(unw_init_local(&cursor, &uc) >= 0, "unw_init_local failed");
- skip_count++; // Do not include current frame
-
- while (skip_count--) {
- if (unw_step(&cursor) <= 0) {
- goto out;
- }
- if (unw_get_reg(&cursor, UNW_REG_SP, &next_sp)) {
- goto out;
- }
- }
-
- while (n < max_depth) {
- if (unw_get_reg(&cursor, UNW_REG_IP, (unw_word_t *) &ip) < 0) {
- break;
- }
- sizes[n] = 0;
- result[n++] = ip;
- if (unw_step(&cursor) <= 0) {
- break;
- }
- sp = next_sp;
- if (unw_get_reg(&cursor, UNW_REG_SP, &next_sp) , 0) {
- break;
- }
- sizes[n - 1] = next_sp - sp;
- }
- if (min_dropped_frames != nullptr) {
- // Implementation detail: we clamp the max of frames we are willing to
- // count, so as not to spend too much time in the loop below.
- const int kMaxUnwind = 200;
- int j = 0;
- for (; j < kMaxUnwind; j++) {
- if (unw_step(&cursor) < 0) {
- break;
- }
- }
- *min_dropped_frames = j;
- }
- } else {
- skip_count++; // Do not include current frame.
- void **result_all = reinterpret_cast<void**>(
- alloca(sizeof(void*) * (max_depth + skip_count)));
- int rc = unw_backtrace(result_all, max_depth + skip_count);
-
- if (rc > 0) {
- // Tell MSan that result_all has been initialized. b/34965936.
- ANNOTATE_MEMORY_IS_INITIALIZED(result_all, rc * sizeof(void*));
- }
-
- if (rc > skip_count) {
- memcpy(result, &result_all[skip_count],
- sizeof(void*) * (rc - skip_count));
- n = rc - skip_count;
- } else {
- n = 0;
- }
-
- if (min_dropped_frames != nullptr) {
- // Not implemented.
- *min_dropped_frames = 0;
- }
- }
-
- out:
- --recursive;
- return n;
-}
-
-#endif // ABSL_DEBUGGING_INTERNAL_STACKTRACE_LIBUNWIND_INL_H_