Add function to trace stack using frame pointers.

base/debug/stack_trace.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_DEBUG_STACK_TRACE_H_
 #define BASE_DEBUG_STACK_TRACE_H_
 
 #include <stddef.h>
 
 #include <iosfwd>
 #include <string>
 
 #include "base/base_export.h"
 #include "build/build_config.h"
 
 #if defined(OS_POSIX)
 #include <unistd.h>
 #endif
 
 #if defined(OS_WIN)
 struct _EXCEPTION_POINTERS;
 struct _CONTEXT;
 #endif
 
+#if defined(OS_POSIX) && (defined(__i386__) || defined(__x86_64__))

[Nico, 2016/04/15 20:00:00]

do we still have any 32-bit posix platforms we need this on?

+#define HAVE_TRACE_STACK_FRAME_POINTERS 1
+#else
+#define HAVE_TRACE_STACK_FRAME_POINTERS 0
+#endif
+
 namespace base {
 namespace debug {
 
 // Enables stack dump to console output on exception and signals.
 // When enabled, the process will quit immediately. This is meant to be used in
 // unit_tests only! This is not thread-safe: only call from main thread.
 // In sandboxed processes, this has to be called before the sandbox is turned
 // on.
 // Calling this function on Linux opens /proc/self/maps and caches its
 // contents. In non-official builds, this function also opens the object files
@@ skipping 34 matching lines @@
   void Print() const;
 
 #if !defined(__UCLIBC__)
   // Resolves backtrace to symbols and write to stream.
   void OutputToStream(std::ostream* os) const;
 #endif
 
   // Resolves backtrace to symbols and returns as string.
   std::string ToString() const;
 
+  static StackTrace FromFramePointers(size_t max_depth);
+
  private:
 #if defined(OS_WIN)
   void InitTrace(const _CONTEXT* context_record);
 #endif
 
   // From http://msdn.microsoft.com/en-us/library/bb204633.aspx,
   // the sum of FramesToSkip and FramesToCapture must be less than 63,
   // so set it to 62. Even if on POSIX it could be a larger value, it usually
   // doesn't give much more information.
   static const int kMaxTraces = 62;
 
   void* trace_[kMaxTraces];
 
   // The number of valid frames in |trace_|.
   size_t count_;
 };
 
+#if HAVE_TRACE_STACK_FRAME_POINTERS
+// Traces the stack by using frame pointers. This function is faster but less
+// reliable than StackTrace. It should work for debug and profiling builds,
+// but not for release builds (although there are some exceptions).
+//
+// Writes at most |max_depth| frames (instruction pointers) into |out_trace|
+// after skipping |skip_initial| frames. Note that the function itself is not
+// added to the trace so |skip_initial| should be 0 in most cases.
+// Returns number of frames written.
+BASE_EXPORT size_t TraceStackFramePointers(const void** out_trace,

[Primiano Tucci (use gerrit), 2016/04/18 20:18:07]

it's a bit conflicting that you have two APIs publicly exposed (this one and
FromFramePointers).
Maybe you want only the one up and this one should be an internal function?

[Dmitry Skiba, 2016/04/20 16:32:56]

Actually, the top one is a mistake. Thanks for noticing!

+                                           size_t max_depth,
+                                           size_t skip_initial);
+#endif  // HAVE_TRACE_STACK_FRAME_POINTERS
+
 namespace internal {
 
 #if defined(OS_POSIX) && !defined(OS_ANDROID)
 // POSIX doesn't define any async-signal safe function for converting
 // an integer to ASCII. We'll have to define our own version.
 // itoa_r() converts a (signed) integer to ASCII. It returns "buf", if the
 // conversion was successful or NULL otherwise. It never writes more than "sz"
 // bytes. Output will be truncated as needed, and a NUL character is always
 // appended.
 BASE_EXPORT char *itoa_r(intptr_t i,
                          char *buf,
                          size_t sz,
                          int base,
                          size_t padding);
 #endif  // defined(OS_POSIX) && !defined(OS_ANDROID)
 
 }  // namespace internal
 
 }  // namespace debug
 }  // namespace base
 
 #endif  // BASE_DEBUG_STACK_TRACE_H_