libsanitizer/sanitizer_common/sanitizer_stacktrace_libcdep.cc

   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
  18 namespace __sanitizer {
  19
  20 void StackTrace::Print() const {
  21   if (trace == nullptr || size == 0) {
  22     Printf("    <empty stack>\n\n");
  23     return;
  24   }
  25   InternalScopedString frame_desc(GetPageSizeCached() * 2);
  26   uptr frame_num = 0;
  27   for (uptr i = 0; i < size && trace[i]; i++) {
  28     // PCs in stack traces are actually the return addresses, that is,
  29     // addresses of the next instructions after the call.
  30     uptr pc = GetPreviousInstructionPc(trace[i]);
  31     SymbolizedStack *frames = Symbolizer::GetOrInit()->SymbolizePC(pc);
  32     CHECK(frames);
  33     for (SymbolizedStack *cur = frames; cur; cur = cur->next) {
  34       frame_desc.clear();
  35       RenderFrame(&frame_desc, common_flags()->stack_trace_format, frame_num++,
  36                   cur->info, common_flags()->symbolize_vs_style,
  37                   common_flags()->strip_path_prefix);
  38       Printf("%s\n", frame_desc.data());
  39     }
  40     frames->ClearAll();
  41   }
  42   // Always print a trailing empty line after stack trace.
  43   Printf("\n");
  44 }
  45
  46 void BufferedStackTrace::Unwind(u32 max_depth, uptr pc, uptr bp, void *context,
  47                                 uptr stack_top, uptr stack_bottom,
  48                                 bool request_fast_unwind) {
  49   top_frame_bp = (max_depth > 0) ? bp : 0;
  50   // Avoid doing any work for small max_depth.
  51   if (max_depth == 0) {
  52     size = 0;
  53     return;
  54   }
  55   if (max_depth == 1) {
  56     size = 1;
  57     trace_buffer[0] = pc;
  58     return;
  59   }
  60   if (!WillUseFastUnwind(request_fast_unwind)) {
  61 #if SANITIZER_CAN_SLOW_UNWIND
  62     if (context)
  63       SlowUnwindStackWithContext(pc, context, max_depth);
  64     else
  65       SlowUnwindStack(pc, max_depth);
  66 #else
  67     UNREACHABLE("slow unwind requested but not available");
  68 #endif
  69   } else {
  70     FastUnwindStack(pc, bp, stack_top, stack_bottom, max_depth);
  71   }
  72 }
  73
  74 }  // namespace __sanitizer