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   InternalScopedString dedup_token(GetPageSizeCached());
  27   int dedup_frames = common_flags()->dedup_token_length;
  28   uptr frame_num = 0;
  29   for (uptr i = 0; i < size && trace[i]; i++) {
  30     // PCs in stack traces are actually the return addresses, that is,
  31     // addresses of the next instructions after the call.
  32     uptr pc = GetPreviousInstructionPc(trace[i]);
  33     SymbolizedStack *frames = Symbolizer::GetOrInit()->SymbolizePC(pc);
  34     CHECK(frames);
  35     for (SymbolizedStack *cur = frames; cur; cur = cur->next) {
  36       frame_desc.clear();
  37       RenderFrame(&frame_desc, common_flags()->stack_trace_format, frame_num++,
  38                   cur->info, common_flags()->symbolize_vs_style,
  39                   common_flags()->strip_path_prefix);
  40       Printf("%s\n", frame_desc.data());
  41       if (dedup_frames-- > 0) {
  42         if (dedup_token.length())
  43           dedup_token.append("--");
  44         if (cur->info.function != nullptr)
  45           dedup_token.append(cur->info.function);
  46       }
  47     }
  48     frames->ClearAll();
  49   }
  50   // Always print a trailing empty line after stack trace.
  51   Printf("\n");
  52   if (dedup_token.length())
  53     Printf("DEDUP_TOKEN: %s\n", dedup_token.data());
  54 }
  55
  56 void BufferedStackTrace::Unwind(u32 max_depth, uptr pc, uptr bp, void *context,
  57                                 uptr stack_top, uptr stack_bottom,
  58                                 bool request_fast_unwind) {
  59   top_frame_bp = (max_depth > 0) ? bp : 0;
  60   // Avoid doing any work for small max_depth.
  61   if (max_depth == 0) {
  62     size = 0;
  63     return;
  64   }
  65   if (max_depth == 1) {
  66     size = 1;
  67     trace_buffer[0] = pc;
  68     return;
  69   }
  70   if (!WillUseFastUnwind(request_fast_unwind)) {
  71 #if SANITIZER_CAN_SLOW_UNWIND
  72     if (context)
  73       SlowUnwindStackWithContext(pc, context, max_depth);
  74     else
  75       SlowUnwindStack(pc, max_depth);
  76 #else
  77     UNREACHABLE("slow unwind requested but not available");
  78 #endif
  79   } else {
  80     FastUnwindStack(pc, bp, stack_top, stack_bottom, max_depth);
  81   }
  82 }
  83
  84 static int GetModuleAndOffsetForPc(uptr pc, char *module_name,
  85                                    uptr module_name_len, uptr *pc_offset) {
  86   const char *found_module_name = nullptr;
  87   bool ok = Symbolizer::GetOrInit()->GetModuleNameAndOffsetForPC(
  88       pc, &found_module_name, pc_offset);
  89
  90   if (!ok) return false;
  91
  92   if (module_name && module_name_len) {
  93     internal_strncpy(module_name, found_module_name, module_name_len);
  94     module_name[module_name_len - 1] = '\x00';
  95   }
  96   return true;
  97 }
  98
  99 }  // namespace __sanitizer
 100 using namespace __sanitizer;
 101
 102 extern "C" {
 103 SANITIZER_INTERFACE_ATTRIBUTE
 104 void __sanitizer_symbolize_pc(uptr pc, const char *fmt, char *out_buf,
 105                               uptr out_buf_size) {
 106   if (!out_buf_size) return;
 107   pc = StackTrace::GetPreviousInstructionPc(pc);
 108   SymbolizedStack *frame = Symbolizer::GetOrInit()->SymbolizePC(pc);
 109   if (!frame) {
 110     internal_strncpy(out_buf, "<can't symbolize>", out_buf_size);
 111     out_buf[out_buf_size - 1] = 0;
 112     return;
 113   }
 114   InternalScopedString frame_desc(GetPageSizeCached());
 115   uptr frame_num = 0;
 116   // Reserve one byte for the final 0.
 117   char *out_end = out_buf + out_buf_size - 1;
 118   for (SymbolizedStack *cur = frame; cur && out_buf < out_end;
 119        cur = cur->next) {
 120     frame_desc.clear();
 121     RenderFrame(&frame_desc, fmt, frame_num++, cur->info,
 122                 common_flags()->symbolize_vs_style,
 123                 common_flags()->strip_path_prefix);
 124     if (!frame_desc.length())
 125       continue;
 126     // Reserve one byte for the terminating 0.
 127     uptr n = out_end - out_buf - 1;
 128     internal_strncpy(out_buf, frame_desc.data(), n);
 129     out_buf += __sanitizer::Min<uptr>(n, frame_desc.length());
 130     *out_buf++ = 0;
 131   }
 132   CHECK(out_buf <= out_end);
 133   *out_buf = 0;
 134 }
 135
 136 SANITIZER_INTERFACE_ATTRIBUTE
 137 void __sanitizer_symbolize_global(uptr data_addr, const char *fmt,
 138                                   char *out_buf, uptr out_buf_size) {
 139   if (!out_buf_size) return;
 140   out_buf[0] = 0;
 141   DataInfo DI;
 142   if (!Symbolizer::GetOrInit()->SymbolizeData(data_addr, &DI)) return;
 143   InternalScopedString data_desc(GetPageSizeCached());
 144   RenderData(&data_desc, fmt, &DI, common_flags()->strip_path_prefix);
 145   internal_strncpy(out_buf, data_desc.data(), out_buf_size);
 146   out_buf[out_buf_size - 1] = 0;
 147 }
 148
 149 SANITIZER_INTERFACE_ATTRIBUTE
 150 int __sanitizer_get_module_and_offset_for_pc( // NOLINT
 151     uptr pc, char *module_name, uptr module_name_len, uptr *pc_offset) {
 152   return __sanitizer::GetModuleAndOffsetForPc(pc, module_name, module_name_len,
 153                                               pc_offset);
 154 }
 155 }  // extern "C"