1//===-- sanitizer_stacktrace_libcdep.cc -----------------------------------===//
2//
3// This file is distributed under the University of Illinois Open Source
4// License. See LICENSE.TXT for details.
5//
6//===----------------------------------------------------------------------===//
7//
8// This file is shared between AddressSanitizer and ThreadSanitizer
9// run-time libraries.
10//===----------------------------------------------------------------------===//
11
12#include "sanitizer_common.h"
13#include "sanitizer_placement_new.h"
14#include "sanitizer_stacktrace.h"
15#include "sanitizer_stacktrace_printer.h"
16#include "sanitizer_symbolizer.h"
17
18namespace __sanitizer {
19
20void StackTrace::Print() const {
21  if (trace == nullptr || size == 0) {
22    Printf("    <empty stack>\n\n");
23    return;
24  }
25  const int kMaxAddrFrames = 64;
26  InternalScopedBuffer<AddressInfo> addr_frames(kMaxAddrFrames);
27  for (uptr i = 0; i < kMaxAddrFrames; i++)
28    new(&addr_frames[i]) AddressInfo();
29  InternalScopedString frame_desc(GetPageSizeCached() * 2);
30  uptr frame_num = 0;
31  for (uptr i = 0; i < size && trace[i]; i++) {
32    // PCs in stack traces are actually the return addresses, that is,
33    // addresses of the next instructions after the call.
34    uptr pc = GetPreviousInstructionPc(trace[i]);
35    uptr addr_frames_num = Symbolizer::GetOrInit()->SymbolizePC(
36        pc, addr_frames.data(), kMaxAddrFrames);
37    if (addr_frames_num == 0) {
38      addr_frames[0].address = pc;
39      addr_frames_num = 1;
40    }
41    for (uptr j = 0; j < addr_frames_num; j++) {
42      AddressInfo &info = addr_frames[j];
43      frame_desc.clear();
44      RenderFrame(&frame_desc, common_flags()->stack_trace_format, frame_num++,
45                  info, common_flags()->strip_path_prefix);
46      Printf("%s\n", frame_desc.data());
47      info.Clear();
48    }
49  }
50  // Always print a trailing empty line after stack trace.
51  Printf("\n");
52}
53
54void BufferedStackTrace::Unwind(uptr max_depth, uptr pc, uptr bp, void *context,
55                                uptr stack_top, uptr stack_bottom,
56                                bool request_fast_unwind) {
57  top_frame_bp = (max_depth > 0) ? bp : 0;
58  // Avoid doing any work for small max_depth.
59  if (max_depth == 0) {
60    size = 0;
61    return;
62  }
63  if (max_depth == 1) {
64    size = 1;
65    trace_buffer[0] = pc;
66    return;
67  }
68  if (!WillUseFastUnwind(request_fast_unwind)) {
69    if (context)
70      SlowUnwindStackWithContext(pc, context, max_depth);
71    else
72      SlowUnwindStack(pc, max_depth);
73  } else {
74    FastUnwindStack(pc, bp, stack_top, stack_bottom, max_depth);
75  }
76}
77
78}  // namespace __sanitizer
79