Import google-glog's Symbolize() and use it in debug_util_posix.cc.

Unlike glibc's backtrace_symbols(), google-glog's Symbolize() can
resolve symbols in binaries built with -fvisibility=hidden. This is
because Symbolize() uses both dynamic and regular symbols, while
backtrace_symbols() only uses dynamic symbols.

As shown below, the new backtrace is slightly less informative as it
does not have the binary name like out/Debug/base_unittests and the
distance information like +0x20, but it should be ok.

BUG=32762
TEST=out/Debug/base_unittests --gtest_filter='StackTrace*' --gtest_also_run_disabled_tests; and manually:

BEFORE
	out/Debug/base_unittests(StackTrace::StackTrace()+0x20) [0x81d38f6]
	out/Debug/base_unittests(StackTrace_DISABLED_DebugOutputToStream_Test::TestBody()+0x17) [0x806633d]
	out/Debug/base_unittests(testing::Test::Run()+0x7a) [0x8242f96]
	out/Debug/base_unittests(testing::internal::TestInfoImpl::Run()+0xb9) [0x824347b]
	out/Debug/base_unittests(testing::TestCase::Run()+0xb7) [0x8243a7f]
	out/Debug/base_unittests(testing::internal::UnitTestImpl::RunAllTests()+0x256) [0x824777e]
	out/Debug/base_unittests(testing::UnitTest::Run()+0x14) [0x824680a]
	out/Debug/base_unittests [0x8048cc5]
	out/Debug/base_unittests(main+0x50) [0x80482a4]
	/lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xe6) [0xb6b41b56]
	out/Debug/base_unittests [0x80481c1]

AFTER
% out/Debug/base_unittests --gtest_filter='*DebugOutputToStream' --gtest_also_run_disabled_tests
	StackTrace::StackTrace() [0x81d3910]
	StackTrace_DISABLED_DebugOutputToStream_Test::TestBody() [0x806633d]
	testing::Test::Run() [0x8242f66]
	testing::internal::TestInfoImpl::Run() [0x824344b]
	testing::TestCase::Run() [0x8243a4f]
	testing::internal::UnitTestImpl::RunAllTests() [0x824774e]
	testing::UnitTest::Run() [0x82467da]
	TestSuite::Run() [0x8048cc5]
	main [0x80482a4]
	0xb6c0db56
	0x80481c1

Review URL: http://codereview.chromium.org/545148

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@36997 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 61 insertions, 16 deletions

diff --git a/base/debug_util_posix.cc b/base/debug_util_posix.cc
index 73b756b..a57f102 100644
--- a/base/debug_util_posix.cc
+++ b/base/debug_util_posix.cc
@@ -17,6 +17,7 @@
 #include <cxxabi.h>
 #endif
 
+#include <iostream>
 #include <string>
 
 #if defined(OS_MACOSX)
@@ -30,6 +31,11 @@
 #include "base/safe_strerror_posix.h"
 #include "base/scoped_ptr.h"
 #include "base/string_piece.h"
+#include "base/string_util.h"
+
+#if defined(USE_SYMBOLIZE)
+#include "base/third_party/symbolize/symbolize.h"
+#endif
 
 namespace {
 // The prefix used for mangled symbols, per the Itanium C++ ABI:
@@ -86,6 +92,48 @@ void DemangleSymbols(std::string* text) {
 
 #endif  // defined(__GLIBCXX__)
 }
+
+// Gets the backtrace as a vector of strings. If possible, resolve symbol
+// names and attach these. Otherwise just use raw addresses. Returns true
+// if any symbol name is resolved.
+bool GetBacktraceStrings(void **trace, int size,
+                         std::vector<std::string>* trace_strings) {
+  bool symbolized = false;
+
+#if defined(USE_SYMBOLIZE)
+  for (int i = 0; i < size; ++i) {
+    char symbol[1024];
+    // Subtract by one as return address of function may be in the next
+    // function when a function is annotated as noreturn.
+    if (google::Symbolize(static_cast<char *>(trace[i]) - 1,
+                          symbol, sizeof(symbol))) {
+      // Don't call DemangleSymbols() here as the symbol is demangled by
+      // google::Symbolize().
+      trace_strings->push_back(StringPrintf("%s [%p]", symbol, trace[i]));
+      symbolized = true;
+    } else {
+      trace_strings->push_back(StringPrintf("%p", trace[i]));
+    }
+  }
+#else
+  scoped_ptr_malloc<char*> trace_symbols(backtrace_symbols(trace, size));
+  if (trace_symbols.get()) {
+    for (int i = 0; i < size; ++i) {
+      std::string trace_symbol = trace_symbols.get()[i];
+      DemangleSymbols(&trace_symbol);
+      trace_strings->push_back(trace_symbol);
+    }
+    symbolized = true;
+  } else {
+    for (int i = 0; i < size; ++i) {
+      trace_strings->push_back(StringPrintf("%p", trace[i]));
+    }
+  }
+#endif  // defined(USE_SYMBOLIZE)
+
+  return symbolized;
+}
+
 }  // namespace
 
 // static
@@ -209,7 +257,11 @@ void StackTrace::PrintBacktrace() {
     return;
 #endif
   fflush(stderr);
-  backtrace_symbols_fd(trace_, count_, STDERR_FILENO);
+  std::vector<std::string> trace_strings;
+  GetBacktraceStrings(trace_, count_, &trace_strings);
+  for (size_t i = 0; i < trace_strings.size(); ++i) {
+    std::cerr << "\t" << trace_strings[i] << "\n";
+  }
 }
 
 void StackTrace::OutputToStream(std::ostream* os) {
@@ -217,22 +269,15 @@ void StackTrace::OutputToStream(std::ostream* os) {
   if (backtrace_symbols == NULL)
     return;
 #endif
-  scoped_ptr_malloc<char*> trace_symbols(backtrace_symbols(trace_, count_));
-
-  // If we can't retrieve the symbols, print an error and just dump the raw
-  // addresses.
-  if (trace_symbols.get() == NULL) {
+  std::vector<std::string> trace_strings;
+  if (GetBacktraceStrings(trace_, count_, &trace_strings)) {
+    (*os) << "Backtrace:\n";
+  } else {
     (*os) << "Unable get symbols for backtrace (" << safe_strerror(errno)
           << "). Dumping raw addresses in trace:\n";
-    for (int i = 0; i < count_; ++i) {
-      (*os) << "\t" << trace_[i] << "\n";
-    }
-  } else {
-    (*os) << "Backtrace:\n";
-    for (int i = 0; i < count_; ++i) {
-      std::string trace_symbol(trace_symbols.get()[i]);
-      DemangleSymbols(&trace_symbol);
-      (*os) << "\t" << trace_symbol << "\n";
-    }
+  }
+
+  for (size_t i = 0; i < trace_strings.size(); ++i) {
+    (*os) << "\t" << trace_strings[i] << "\n";
   }
 }