THUAI6/CAPI/cpp/grpc/include/absl/debugging/internal/examine_stack.h

//
// Copyright 2018 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.
//

#ifndef ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
#define ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_

#include "absl/base/config.h"

namespace absl
{
    ABSL_NAMESPACE_BEGIN
    namespace debugging_internal
    {

        // Type of function used for printing in stack trace dumping, etc.
        // We avoid closures to keep things simple.
        typedef void OutputWriter(const char*, void*);

        // RegisterDebugStackTraceHook() allows to register a single routine
        // `hook` that is called each time DumpStackTrace() is called.
        // `hook` may be called from a signal handler.
        typedef void (*SymbolizeUrlEmitter)(void* const stack[], int depth, OutputWriter* writer, void* writer_arg);

        // Registration of SymbolizeUrlEmitter for use inside of a signal handler.
        // This is inherently unsafe and must be signal safe code.
        void RegisterDebugStackTraceHook(SymbolizeUrlEmitter hook);
        SymbolizeUrlEmitter GetDebugStackTraceHook();

        // Returns the program counter from signal context, or nullptr if
        // unknown. `vuc` is a ucontext_t*. We use void* to avoid the use of
        // ucontext_t on non-POSIX systems.
        void* GetProgramCounter(void* const vuc);

        // Uses `writer` to dump the program counter, stack trace, and stack
        // frame sizes.
        void DumpPCAndFrameSizesAndStackTrace(void* const pc, void* const stack[], int frame_sizes[], int depth, int min_dropped_frames, bool symbolize_stacktrace, OutputWriter* writer, void* writer_arg);

        // Dump current stack trace omitting the topmost `min_dropped_frames` stack
        // frames.
        void DumpStackTrace(int min_dropped_frames, int max_num_frames, bool symbolize_stacktrace, OutputWriter* writer, void* writer_arg);

    }  // namespace debugging_internal
    ABSL_NAMESPACE_END
}  // namespace absl

#endif  // ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_