557 lines
18 KiB
C++
557 lines
18 KiB
C++
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#include "base/debug/stack_trace.h"
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#include <errno.h>
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#include <execinfo.h>
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#include <fcntl.h>
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#include <signal.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/param.h>
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <unistd.h>
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#include <ostream>
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#if defined(__GLIBCXX__)
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#include <cxxabi.h>
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#endif
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#if defined(OS_MACOSX)
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#include <AvailabilityMacros.h>
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#endif
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#include "base/basictypes.h"
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#include "base/debug/debugger.h"
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#include "base/logging.h"
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#include "base/memory/scoped_ptr.h"
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#include "base/posix/eintr_wrapper.h"
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#include "base/strings/string_number_conversions.h"
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#if defined(USE_SYMBOLIZE)
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#include "base/third_party/symbolize/symbolize.h"
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#endif
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namespace base {
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namespace debug {
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namespace {
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volatile sig_atomic_t in_signal_handler = 0;
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// The prefix used for mangled symbols, per the Itanium C++ ABI:
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// http://www.codesourcery.com/cxx-abi/abi.html#mangling
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const char kMangledSymbolPrefix[] = "_Z";
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// Characters that can be used for symbols, generated by Ruby:
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// (('a'..'z').to_a+('A'..'Z').to_a+('0'..'9').to_a + ['_']).join
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const char kSymbolCharacters[] =
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"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
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#if !defined(USE_SYMBOLIZE)
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// Demangles C++ symbols in the given text. Example:
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//
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// "out/Debug/base_unittests(_ZN10StackTraceC1Ev+0x20) [0x817778c]"
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// =>
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// "out/Debug/base_unittests(StackTrace::StackTrace()+0x20) [0x817778c]"
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void DemangleSymbols(std::string* text) {
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// Note: code in this function is NOT async-signal safe (std::string uses
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// malloc internally).
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#if defined(__GLIBCXX__)
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std::string::size_type search_from = 0;
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while (search_from < text->size()) {
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// Look for the start of a mangled symbol, from search_from.
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std::string::size_type mangled_start =
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text->find(kMangledSymbolPrefix, search_from);
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if (mangled_start == std::string::npos) {
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break; // Mangled symbol not found.
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}
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// Look for the end of the mangled symbol.
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std::string::size_type mangled_end =
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text->find_first_not_of(kSymbolCharacters, mangled_start);
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if (mangled_end == std::string::npos) {
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mangled_end = text->size();
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}
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std::string mangled_symbol =
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text->substr(mangled_start, mangled_end - mangled_start);
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// Try to demangle the mangled symbol candidate.
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int status = 0;
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scoped_ptr_malloc<char> demangled_symbol(
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abi::__cxa_demangle(mangled_symbol.c_str(), NULL, 0, &status));
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if (status == 0) { // Demangling is successful.
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// Remove the mangled symbol.
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text->erase(mangled_start, mangled_end - mangled_start);
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// Insert the demangled symbol.
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text->insert(mangled_start, demangled_symbol.get());
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// Next time, we'll start right after the demangled symbol we inserted.
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search_from = mangled_start + strlen(demangled_symbol.get());
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} else {
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// Failed to demangle. Retry after the "_Z" we just found.
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search_from = mangled_start + 2;
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}
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}
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#endif // defined(__GLIBCXX__)
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}
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#endif // !defined(USE_SYMBOLIZE)
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class BacktraceOutputHandler {
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public:
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virtual void HandleOutput(const char* output) = 0;
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protected:
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virtual ~BacktraceOutputHandler() {}
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};
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void OutputPointer(void* pointer, BacktraceOutputHandler* handler) {
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char buf[1024] = { '\0' };
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handler->HandleOutput(" [0x");
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internal::itoa_r(reinterpret_cast<intptr_t>(pointer),
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buf, sizeof(buf), 16, 12);
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handler->HandleOutput(buf);
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handler->HandleOutput("]");
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}
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void ProcessBacktrace(void *const *trace,
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int size,
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BacktraceOutputHandler* handler) {
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// NOTE: This code MUST be async-signal safe (it's used by in-process
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// stack dumping signal handler). NO malloc or stdio is allowed here.
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#if defined(USE_SYMBOLIZE)
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for (int i = 0; i < size; ++i) {
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OutputPointer(trace[i], handler);
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handler->HandleOutput(" ");
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char buf[1024] = { '\0' };
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// Subtract by one as return address of function may be in the next
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// function when a function is annotated as noreturn.
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void* address = static_cast<char*>(trace[i]) - 1;
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if (google::Symbolize(address, buf, sizeof(buf)))
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handler->HandleOutput(buf);
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else
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handler->HandleOutput("<unknown>");
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handler->HandleOutput("\n");
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}
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#else
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bool printed = false;
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// Below part is async-signal unsafe (uses malloc), so execute it only
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// when we are not executing the signal handler.
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if (in_signal_handler == 0) {
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scoped_ptr_malloc<char*> trace_symbols(backtrace_symbols(trace, size));
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if (trace_symbols.get()) {
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for (int i = 0; i < size; ++i) {
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std::string trace_symbol = trace_symbols.get()[i];
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DemangleSymbols(&trace_symbol);
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handler->HandleOutput(trace_symbol.c_str());
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handler->HandleOutput("\n");
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}
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printed = true;
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}
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}
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if (!printed) {
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for (int i = 0; i < size; ++i) {
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OutputPointer(trace[i], handler);
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handler->HandleOutput("\n");
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}
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}
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#endif // defined(USE_SYMBOLIZE)
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}
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void PrintToStderr(const char* output) {
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// NOTE: This code MUST be async-signal safe (it's used by in-process
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// stack dumping signal handler). NO malloc or stdio is allowed here.
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ignore_result(HANDLE_EINTR(write(STDERR_FILENO, output, strlen(output))));
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}
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void StackDumpSignalHandler(int signal, siginfo_t* info, void* void_context) {
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// NOTE: This code MUST be async-signal safe.
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// NO malloc or stdio is allowed here.
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// Record the fact that we are in the signal handler now, so that the rest
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// of StackTrace can behave in an async-signal-safe manner.
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in_signal_handler = 1;
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if (BeingDebugged())
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BreakDebugger();
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PrintToStderr("Received signal ");
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char buf[1024] = { 0 };
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internal::itoa_r(signal, buf, sizeof(buf), 10, 0);
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PrintToStderr(buf);
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if (signal == SIGBUS) {
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if (info->si_code == BUS_ADRALN)
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PrintToStderr(" BUS_ADRALN ");
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else if (info->si_code == BUS_ADRERR)
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PrintToStderr(" BUS_ADRERR ");
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else if (info->si_code == BUS_OBJERR)
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PrintToStderr(" BUS_OBJERR ");
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else
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PrintToStderr(" <unknown> ");
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} else if (signal == SIGFPE) {
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if (info->si_code == FPE_FLTDIV)
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PrintToStderr(" FPE_FLTDIV ");
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else if (info->si_code == FPE_FLTINV)
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PrintToStderr(" FPE_FLTINV ");
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else if (info->si_code == FPE_FLTOVF)
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PrintToStderr(" FPE_FLTOVF ");
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else if (info->si_code == FPE_FLTRES)
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PrintToStderr(" FPE_FLTRES ");
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else if (info->si_code == FPE_FLTSUB)
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PrintToStderr(" FPE_FLTSUB ");
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else if (info->si_code == FPE_FLTUND)
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PrintToStderr(" FPE_FLTUND ");
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else if (info->si_code == FPE_INTDIV)
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PrintToStderr(" FPE_INTDIV ");
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else if (info->si_code == FPE_INTOVF)
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PrintToStderr(" FPE_INTOVF ");
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else
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PrintToStderr(" <unknown> ");
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} else if (signal == SIGILL) {
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if (info->si_code == ILL_BADSTK)
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PrintToStderr(" ILL_BADSTK ");
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else if (info->si_code == ILL_COPROC)
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PrintToStderr(" ILL_COPROC ");
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else if (info->si_code == ILL_ILLOPN)
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PrintToStderr(" ILL_ILLOPN ");
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else if (info->si_code == ILL_ILLADR)
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PrintToStderr(" ILL_ILLADR ");
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else if (info->si_code == ILL_ILLTRP)
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PrintToStderr(" ILL_ILLTRP ");
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else if (info->si_code == ILL_PRVOPC)
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PrintToStderr(" ILL_PRVOPC ");
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else if (info->si_code == ILL_PRVREG)
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PrintToStderr(" ILL_PRVREG ");
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else
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PrintToStderr(" <unknown> ");
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} else if (signal == SIGSEGV) {
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if (info->si_code == SEGV_MAPERR)
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PrintToStderr(" SEGV_MAPERR ");
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else if (info->si_code == SEGV_ACCERR)
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PrintToStderr(" SEGV_ACCERR ");
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else
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PrintToStderr(" <unknown> ");
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}
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if (signal == SIGBUS || signal == SIGFPE ||
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signal == SIGILL || signal == SIGSEGV) {
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internal::itoa_r(reinterpret_cast<intptr_t>(info->si_addr),
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buf, sizeof(buf), 16, 12);
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PrintToStderr(buf);
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}
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PrintToStderr("\n");
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debug::StackTrace().PrintBacktrace();
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#if defined(OS_LINUX)
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#if ARCH_CPU_X86_FAMILY
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ucontext_t* context = reinterpret_cast<ucontext_t*>(void_context);
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const struct {
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const char* label;
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greg_t value;
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} registers[] = {
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#if ARCH_CPU_32_BITS
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{ " gs: ", context->uc_mcontext.gregs[REG_GS] },
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{ " fs: ", context->uc_mcontext.gregs[REG_FS] },
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{ " es: ", context->uc_mcontext.gregs[REG_ES] },
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{ " ds: ", context->uc_mcontext.gregs[REG_DS] },
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{ " edi: ", context->uc_mcontext.gregs[REG_EDI] },
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{ " esi: ", context->uc_mcontext.gregs[REG_ESI] },
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{ " ebp: ", context->uc_mcontext.gregs[REG_EBP] },
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{ " esp: ", context->uc_mcontext.gregs[REG_ESP] },
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{ " ebx: ", context->uc_mcontext.gregs[REG_EBX] },
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{ " edx: ", context->uc_mcontext.gregs[REG_EDX] },
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{ " ecx: ", context->uc_mcontext.gregs[REG_ECX] },
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{ " eax: ", context->uc_mcontext.gregs[REG_EAX] },
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{ " trp: ", context->uc_mcontext.gregs[REG_TRAPNO] },
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{ " err: ", context->uc_mcontext.gregs[REG_ERR] },
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{ " ip: ", context->uc_mcontext.gregs[REG_EIP] },
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{ " cs: ", context->uc_mcontext.gregs[REG_CS] },
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{ " efl: ", context->uc_mcontext.gregs[REG_EFL] },
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{ " usp: ", context->uc_mcontext.gregs[REG_UESP] },
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{ " ss: ", context->uc_mcontext.gregs[REG_SS] },
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#elif ARCH_CPU_64_BITS
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{ " r8: ", context->uc_mcontext.gregs[REG_R8] },
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{ " r9: ", context->uc_mcontext.gregs[REG_R9] },
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{ " r10: ", context->uc_mcontext.gregs[REG_R10] },
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{ " r11: ", context->uc_mcontext.gregs[REG_R11] },
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{ " r12: ", context->uc_mcontext.gregs[REG_R12] },
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{ " r13: ", context->uc_mcontext.gregs[REG_R13] },
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{ " r14: ", context->uc_mcontext.gregs[REG_R14] },
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{ " r15: ", context->uc_mcontext.gregs[REG_R15] },
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{ " di: ", context->uc_mcontext.gregs[REG_RDI] },
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{ " si: ", context->uc_mcontext.gregs[REG_RSI] },
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{ " bp: ", context->uc_mcontext.gregs[REG_RBP] },
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{ " bx: ", context->uc_mcontext.gregs[REG_RBX] },
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{ " dx: ", context->uc_mcontext.gregs[REG_RDX] },
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{ " ax: ", context->uc_mcontext.gregs[REG_RAX] },
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{ " cx: ", context->uc_mcontext.gregs[REG_RCX] },
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{ " sp: ", context->uc_mcontext.gregs[REG_RSP] },
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{ " ip: ", context->uc_mcontext.gregs[REG_RIP] },
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{ " efl: ", context->uc_mcontext.gregs[REG_EFL] },
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{ " cgf: ", context->uc_mcontext.gregs[REG_CSGSFS] },
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{ " erf: ", context->uc_mcontext.gregs[REG_ERR] },
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{ " trp: ", context->uc_mcontext.gregs[REG_TRAPNO] },
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{ " msk: ", context->uc_mcontext.gregs[REG_OLDMASK] },
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{ " cr2: ", context->uc_mcontext.gregs[REG_CR2] },
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#endif
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};
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#if ARCH_CPU_32_BITS
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const int kRegisterPadding = 8;
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#elif ARCH_CPU_64_BITS
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const int kRegisterPadding = 16;
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#endif
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for (size_t i = 0; i < ARRAYSIZE_UNSAFE(registers); i++) {
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PrintToStderr(registers[i].label);
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internal::itoa_r(registers[i].value, buf, sizeof(buf),
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16, kRegisterPadding);
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PrintToStderr(buf);
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if ((i + 1) % 4 == 0)
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PrintToStderr("\n");
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}
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PrintToStderr("\n");
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#endif
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#elif defined(OS_MACOSX)
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// TODO(shess): Port to 64-bit.
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#if ARCH_CPU_X86_FAMILY && ARCH_CPU_32_BITS
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ucontext_t* context = reinterpret_cast<ucontext_t*>(void_context);
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size_t len;
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// NOTE: Even |snprintf()| is not on the approved list for signal
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// handlers, but buffered I/O is definitely not on the list due to
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// potential for |malloc()|.
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len = static_cast<size_t>(
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snprintf(buf, sizeof(buf),
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"ax: %x, bx: %x, cx: %x, dx: %x\n",
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context->uc_mcontext->__ss.__eax,
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context->uc_mcontext->__ss.__ebx,
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context->uc_mcontext->__ss.__ecx,
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context->uc_mcontext->__ss.__edx));
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write(STDERR_FILENO, buf, std::min(len, sizeof(buf) - 1));
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len = static_cast<size_t>(
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snprintf(buf, sizeof(buf),
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"di: %x, si: %x, bp: %x, sp: %x, ss: %x, flags: %x\n",
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context->uc_mcontext->__ss.__edi,
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context->uc_mcontext->__ss.__esi,
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context->uc_mcontext->__ss.__ebp,
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context->uc_mcontext->__ss.__esp,
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context->uc_mcontext->__ss.__ss,
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context->uc_mcontext->__ss.__eflags));
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write(STDERR_FILENO, buf, std::min(len, sizeof(buf) - 1));
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len = static_cast<size_t>(
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snprintf(buf, sizeof(buf),
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"ip: %x, cs: %x, ds: %x, es: %x, fs: %x, gs: %x\n",
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context->uc_mcontext->__ss.__eip,
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context->uc_mcontext->__ss.__cs,
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context->uc_mcontext->__ss.__ds,
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context->uc_mcontext->__ss.__es,
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context->uc_mcontext->__ss.__fs,
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context->uc_mcontext->__ss.__gs));
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write(STDERR_FILENO, buf, std::min(len, sizeof(buf) - 1));
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#endif // ARCH_CPU_32_BITS
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#endif // defined(OS_MACOSX)
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_exit(1);
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}
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class PrintBacktraceOutputHandler : public BacktraceOutputHandler {
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public:
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PrintBacktraceOutputHandler() {}
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virtual void HandleOutput(const char* output) OVERRIDE {
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// NOTE: This code MUST be async-signal safe (it's used by in-process
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// stack dumping signal handler). NO malloc or stdio is allowed here.
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PrintToStderr(output);
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}
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private:
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DISALLOW_COPY_AND_ASSIGN(PrintBacktraceOutputHandler);
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};
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class StreamBacktraceOutputHandler : public BacktraceOutputHandler {
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public:
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explicit StreamBacktraceOutputHandler(std::ostream* os) : os_(os) {
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}
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virtual void HandleOutput(const char* output) OVERRIDE {
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(*os_) << output;
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}
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private:
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std::ostream* os_;
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DISALLOW_COPY_AND_ASSIGN(StreamBacktraceOutputHandler);
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};
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void WarmUpBacktrace() {
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// Warm up stack trace infrastructure. It turns out that on the first
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// call glibc initializes some internal data structures using pthread_once,
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// and even backtrace() can call malloc(), leading to hangs.
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//
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// Example stack trace snippet (with tcmalloc):
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//
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// #8 0x0000000000a173b5 in tc_malloc
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// at ./third_party/tcmalloc/chromium/src/debugallocation.cc:1161
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// #9 0x00007ffff7de7900 in _dl_map_object_deps at dl-deps.c:517
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// #10 0x00007ffff7ded8a9 in dl_open_worker at dl-open.c:262
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// #11 0x00007ffff7de9176 in _dl_catch_error at dl-error.c:178
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// #12 0x00007ffff7ded31a in _dl_open (file=0x7ffff625e298 "libgcc_s.so.1")
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// at dl-open.c:639
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// #13 0x00007ffff6215602 in do_dlopen at dl-libc.c:89
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// #14 0x00007ffff7de9176 in _dl_catch_error at dl-error.c:178
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// #15 0x00007ffff62156c4 in dlerror_run at dl-libc.c:48
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// #16 __GI___libc_dlopen_mode at dl-libc.c:165
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// #17 0x00007ffff61ef8f5 in init
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// at ../sysdeps/x86_64/../ia64/backtrace.c:53
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// #18 0x00007ffff6aad400 in pthread_once
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// at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_once.S:104
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// #19 0x00007ffff61efa14 in __GI___backtrace
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// at ../sysdeps/x86_64/../ia64/backtrace.c:104
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// #20 0x0000000000752a54 in base::debug::StackTrace::StackTrace
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// at base/debug/stack_trace_posix.cc:175
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// #21 0x00000000007a4ae5 in
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// base::(anonymous namespace)::StackDumpSignalHandler
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// at base/process_util_posix.cc:172
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// #22 <signal handler called>
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StackTrace stack_trace;
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}
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|
} // namespace
|
|
|
|
#if !defined(OS_IOS)
|
|
bool EnableInProcessStackDumping() {
|
|
// When running in an application, our code typically expects SIGPIPE
|
|
// to be ignored. Therefore, when testing that same code, it should run
|
|
// with SIGPIPE ignored as well.
|
|
struct sigaction sigpipe_action;
|
|
memset(&sigpipe_action, 0, sizeof(sigpipe_action));
|
|
sigpipe_action.sa_handler = SIG_IGN;
|
|
sigemptyset(&sigpipe_action.sa_mask);
|
|
bool success = (sigaction(SIGPIPE, &sigpipe_action, NULL) == 0);
|
|
|
|
// Avoid hangs during backtrace initialization, see above.
|
|
WarmUpBacktrace();
|
|
|
|
struct sigaction action;
|
|
memset(&action, 0, sizeof(action));
|
|
action.sa_flags = SA_RESETHAND | SA_SIGINFO;
|
|
action.sa_sigaction = &StackDumpSignalHandler;
|
|
sigemptyset(&action.sa_mask);
|
|
|
|
success &= (sigaction(SIGILL, &action, NULL) == 0);
|
|
success &= (sigaction(SIGABRT, &action, NULL) == 0);
|
|
success &= (sigaction(SIGFPE, &action, NULL) == 0);
|
|
success &= (sigaction(SIGBUS, &action, NULL) == 0);
|
|
success &= (sigaction(SIGSEGV, &action, NULL) == 0);
|
|
success &= (sigaction(SIGSYS, &action, NULL) == 0);
|
|
|
|
return success;
|
|
}
|
|
#endif // !defined(OS_IOS)
|
|
|
|
StackTrace::StackTrace() {
|
|
// NOTE: This code MUST be async-signal safe (it's used by in-process
|
|
// stack dumping signal handler). NO malloc or stdio is allowed here.
|
|
|
|
// Though the backtrace API man page does not list any possible negative
|
|
// return values, we take no chance.
|
|
count_ = std::max(backtrace(trace_, arraysize(trace_)), 0);
|
|
}
|
|
|
|
void StackTrace::PrintBacktrace() const {
|
|
// NOTE: This code MUST be async-signal safe (it's used by in-process
|
|
// stack dumping signal handler). NO malloc or stdio is allowed here.
|
|
|
|
PrintBacktraceOutputHandler handler;
|
|
ProcessBacktrace(trace_, count_, &handler);
|
|
}
|
|
|
|
void StackTrace::OutputToStream(std::ostream* os) const {
|
|
StreamBacktraceOutputHandler handler(os);
|
|
ProcessBacktrace(trace_, count_, &handler);
|
|
}
|
|
|
|
namespace internal {
|
|
|
|
// NOTE: code from sandbox/linux/seccomp-bpf/demo.cc.
|
|
char *itoa_r(intptr_t i, char *buf, size_t sz, int base, size_t padding) {
|
|
// Make sure we can write at least one NUL byte.
|
|
size_t n = 1;
|
|
if (n > sz)
|
|
return NULL;
|
|
|
|
if (base < 2 || base > 16) {
|
|
buf[0] = '\000';
|
|
return NULL;
|
|
}
|
|
|
|
char *start = buf;
|
|
|
|
uintptr_t j = i;
|
|
|
|
// Handle negative numbers (only for base 10).
|
|
if (i < 0 && base == 10) {
|
|
j = -i;
|
|
|
|
// Make sure we can write the '-' character.
|
|
if (++n > sz) {
|
|
buf[0] = '\000';
|
|
return NULL;
|
|
}
|
|
*start++ = '-';
|
|
}
|
|
|
|
// Loop until we have converted the entire number. Output at least one
|
|
// character (i.e. '0').
|
|
char *ptr = start;
|
|
do {
|
|
// Make sure there is still enough space left in our output buffer.
|
|
if (++n > sz) {
|
|
buf[0] = '\000';
|
|
return NULL;
|
|
}
|
|
|
|
// Output the next digit.
|
|
*ptr++ = "0123456789abcdef"[j % base];
|
|
j /= base;
|
|
|
|
if (padding > 0)
|
|
padding--;
|
|
} while (j > 0 || padding > 0);
|
|
|
|
// Terminate the output with a NUL character.
|
|
*ptr = '\000';
|
|
|
|
// Conversion to ASCII actually resulted in the digits being in reverse
|
|
// order. We can't easily generate them in forward order, as we can't tell
|
|
// the number of characters needed until we are done converting.
|
|
// So, now, we reverse the string (except for the possible "-" sign).
|
|
while (--ptr > start) {
|
|
char ch = *ptr;
|
|
*ptr = *start;
|
|
*start++ = ch;
|
|
}
|
|
return buf;
|
|
}
|
|
|
|
} // namespace internal
|
|
|
|
} // namespace debug
|
|
} // namespace base
|