/**************************************************************************/
/* crash_handler_linuxbsd.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "crash_handler_linuxbsd.h"
#include "core/config/project_settings.h"
#include "core/io/file_access.h"
#include "core/object/script_language.h"
#include "core/os/main_loop.h"
#include "core/os/os.h"
#include "core/string/print_string.h"
#include "core/version.h"
#include "main/main.h"
#ifndef DEBUG_ENABLED
#undef CRASH_HANDLER_ENABLED
#endif
#ifdef CRASH_HANDLER_ENABLED
#include <cxxabi.h>
#include <dlfcn.h>
#include <execinfo.h>
#include <link.h>
#include <csignal>
#include <cstdio>
#include <cstdlib>
inline String find_addr2line_executable() {
List<String> args;
args.push_back("--version");
String output;
OS *os = OS::get_singleton();
int ret = 0;
Error err = OK;
// First, check for addr2line in the home directory's cargo bin.
if (os->has_environment("HOME")) {
// Faster implementation from gimli-rs/addr2line.
const String cargo_addr2line = os->get_environment("HOME").path_join(String("/.cargo/bin/addr2line"));
err = os->execute(cargo_addr2line, args, &output, &ret);
if (err == OK && ret == 0) {
return cargo_addr2line;
}
}
// Otherwise, check for llvm-addr2line.
err = os->execute(String("llvm-addr2line"), args, &output, &ret);
if (err == OK && ret == 0) {
return String("llvm-addr2line");
}
// Fallback guess if none of the above returned a definitive result.
return String("addr2line");
}
static void handle_crash(int sig) {
signal(SIGSEGV, SIG_DFL);
signal(SIGFPE, SIG_DFL);
signal(SIGILL, SIG_DFL);
if (OS::get_singleton() == nullptr) {
abort();
}
if (OS::get_singleton()->is_crash_handler_silent()) {
std::_Exit(0);
}
void *bt_buffer[256];
size_t size = backtrace(bt_buffer, 256);
String _execpath = OS::get_singleton()->get_executable_path();
if (FileAccess::exists(_execpath + ".debugsymbols")) {
_execpath = _execpath + ".debugsymbols";
}
String msg;
if (ProjectSettings::get_singleton()) {
msg = GLOBAL_GET("debug/settings/crash_handler/message");
}
// Tell MainLoop about the crash. This can be handled by users too in Node.
if (OS::get_singleton()->get_main_loop()) {
OS::get_singleton()->get_main_loop()->notification(MainLoop::NOTIFICATION_CRASH);
}
// Dump the backtrace to stderr with a message to the user
print_error("\n================================================================");
print_error(vformat("%s: Program crashed with signal %d", __FUNCTION__, sig));
// Print the engine version just before, so that people are reminded to include the version in backtrace reports.
if (String(GODOT_VERSION_HASH).is_empty()) {
print_error(vformat("Engine version: %s", GODOT_VERSION_FULL_NAME));
} else {
print_error(vformat("Engine version: %s (%s)", GODOT_VERSION_FULL_NAME, GODOT_VERSION_HASH));
}
print_error(vformat("Dumping the backtrace. %s", msg));
char **strings = backtrace_symbols(bt_buffer, size);
// PIE executable relocation, zero for non-PIE executables
#ifdef __GLIBC__
// This is a glibc only thing apparently.
uintptr_t relocation = _r_debug.r_map->l_addr;
#else
// Non glibc systems apparently don't give PIE relocation info.
uintptr_t relocation = 0;
#endif //__GLIBC__
void *load_addr = nullptr;
{
Dl_info info;
if (dladdr(bt_buffer[size - 1], &info)) {
load_addr = info.dli_fbase;
}
}
print_error(vformat("Load address: %x\n", (uint64_t)load_addr));
if (strings) {
int ret;
const String exe_name = find_addr2line_executable();
List<String> args;
for (size_t i = 0; i < size; i++) {
char str[1024];
snprintf(str, 1024, "%p", (void *)((uintptr_t)bt_buffer[i] - relocation));
args.push_back(str);
}
args.push_back("-e");
args.push_back(_execpath);
args.push_back("-f");
args.push_back("-p");
args.push_back("-C");
// Try to get the file/line number using addr2line
String addr2line_output;
Error err = OS::get_singleton()->execute(exe_name, args, &addr2line_output, &ret);
if (err == OK) {
Vector<String> addr2line_results = addr2line_output.substr(0, addr2line_output.length() - 1).split("\n", false);
for (size_t i = 1; i < size; i++) {
String output = addr2line_results[i].replace("/./", "/");
String mod_name = "main";
uint64_t mod_off = (uint64_t)load_addr;
bool addr2line_fail = output.strip_edges().ends_with("??:0");
if (addr2line_fail) {
output = String(strings[i]);
}
Dl_info info;
if (dladdr(bt_buffer[i], &info)) {
mod_off = (uint64_t)info.dli_fbase;
if (mod_off != (uint64_t)load_addr) {
mod_name = String(info.dli_fname).get_file();
}
if (addr2line_fail && info.dli_sname && info.dli_sname[0] == '_') {
int status = 0;
char *demangled = abi::__cxa_demangle(info.dli_sname, nullptr, nullptr, &status);
if (status == 0 && demangled) {
output = String(demangled);
}
if (demangled) {
free(demangled);
}
}
} else {
mod_name = "<unknown module>";
}
// Simplify printed file paths to remove redundant `/./` sections (e.g. `/opt/godot/./core` -> `/opt/godot/core`).
print_error(vformat("[%d] %x (%s+%x) - %s", (int64_t)i, (uint64_t)bt_buffer[i], mod_name, (uint64_t)bt_buffer[i] - mod_off, output));
}
} else {
// Otherwise fall back to trace symbols.
for (size_t i = 1; i < size; i++) {
String output = String(strings[i]);
String mod_name = "main";
uint64_t mod_off = (uint64_t)load_addr;
Dl_info info;
// Try to demangle the function name to provide a more readable one.
if (dladdr(bt_buffer[i], &info)) {
mod_off = (uint64_t)info.dli_fbase;
if (mod_off != (uint64_t)load_addr) {
mod_name = String(info.dli_fname).get_file();
}
if (info.dli_sname && info.dli_sname[0] == '_') {
int status = 0;
char *demangled = abi::__cxa_demangle(info.dli_sname, nullptr, nullptr, &status);
if (status == 0 && demangled) {
output = String(demangled);
}
if (demangled) {
free(demangled);
}
}
} else {
mod_name = "<unknown module>";
}
print_error(vformat("[%d] %x (%s+%x) - %s", (int64_t)i, (uint64_t)bt_buffer[i], mod_name, (uint64_t)bt_buffer[i] - mod_off, output));
}
}
free(strings);
}
print_error("-- END OF C++ BACKTRACE --");
print_error("================================================================");
for (const Ref<ScriptBacktrace> &backtrace : ScriptServer::capture_script_backtraces(false)) {
if (!backtrace->is_empty()) {
print_error(backtrace->format());
print_error(vformat("-- END OF %s BACKTRACE --", backtrace->get_language_name().to_upper()));
print_error("================================================================");
}
}
// Abort to pass the error to the OS
abort();
}
#endif
CrashHandler::CrashHandler() {
disabled = false;
}
CrashHandler::~CrashHandler() {
disable();
}
void CrashHandler::disable() {
if (disabled) {
return;
}
#ifdef CRASH_HANDLER_ENABLED
signal(SIGSEGV, SIG_DFL);
signal(SIGFPE, SIG_DFL);
signal(SIGILL, SIG_DFL);
#endif
disabled = true;
}
void CrashHandler::initialize() {
#ifdef CRASH_HANDLER_ENABLED
signal(SIGSEGV, handle_crash);
signal(SIGFPE, handle_crash);
signal(SIGILL, handle_crash);
#endif
}