contrib/llvm-project/compiler-rt/lib/gwp_asan/optional/backtrace_sanitizer_common.cpp

   1 //===-- backtrace_sanitizer_common.cpp --------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include <assert.h>
  10 #include <stddef.h>
  11 #include <stdint.h>
  12 #include <string.h>
  13
  14 #include "gwp_asan/optional/backtrace.h"
  15 #include "gwp_asan/options.h"
  16 #include "sanitizer_common/sanitizer_stacktrace.h"
  17
  18 void __sanitizer::BufferedStackTrace::UnwindImpl(uptr pc, uptr bp,
  19                                                  void *context,
  20                                                  bool request_fast,
  21                                                  u32 max_depth) {
  22   if (!StackTrace::WillUseFastUnwind(request_fast)) {
  23     return Unwind(max_depth, pc, bp, context, 0, 0, request_fast);
  24   }
  25   Unwind(max_depth, pc, 0, context, 0, 0, false);
  26 }
  27
  28 namespace {
  29 void Backtrace(uintptr_t *TraceBuffer, size_t Size) {
  30   __sanitizer::BufferedStackTrace Trace;
  31   Trace.Reset();
  32   if (Size > __sanitizer::kStackTraceMax)
  33     Size = __sanitizer::kStackTraceMax;
  34
  35   Trace.Unwind((__sanitizer::uptr)__builtin_return_address(0),
  36                (__sanitizer::uptr)__builtin_frame_address(0),
  37                /* ucontext */ nullptr,
  38                /* fast unwind */ true, Size - 1);
  39
  40   memcpy(TraceBuffer, Trace.trace, Trace.size * sizeof(uintptr_t));
  41   TraceBuffer[Trace.size] = 0;
  42 }
  43
  44 static void PrintBacktrace(uintptr_t *Trace,
  45                            gwp_asan::options::Printf_t Printf) {
  46   __sanitizer::StackTrace StackTrace;
  47   StackTrace.trace = reinterpret_cast<__sanitizer::uptr *>(Trace);
  48
  49   for (StackTrace.size = 0; StackTrace.size < __sanitizer::kStackTraceMax;
  50        ++StackTrace.size) {
  51     if (Trace[StackTrace.size] == 0)
  52       break;
  53   }
  54
  55   if (StackTrace.size == 0) {
  56     Printf("  <unknown (does your allocator support backtracing?)>\n\n");
  57     return;
  58   }
  59
  60   StackTrace.Print();
  61 }
  62 } // anonymous namespace
  63
  64 namespace gwp_asan {
  65 namespace options {
  66 Backtrace_t getBacktraceFunction() { return Backtrace; }
  67 PrintBacktrace_t getPrintBacktraceFunction() { return PrintBacktrace; }
  68 } // namespace options
  69 } // namespace gwp_asan