Add a segfault handler to dump the backtrace on Windows, Linux and OS X

core/os/os.h

@@ -279,6 +279,9 @@ class OS {
 
 	bool is_stdout_verbose() const;
 
+	virtual void disable_crash_handler() {}
+	virtual bool is_disable_crash_handler() const { return false; }
+
 	enum CursorShape {
 		CURSOR_ARROW,
 		CURSOR_IBEAM,

editor/editor_run.cpp

@@ -72,6 +72,10 @@ Error EditorRun::run(const String &p_scene, const String p_custom_args, const Li
 		screen--;
 	}
 
+	if (OS::get_singleton()->is_disable_crash_handler()) {
+		args.push_back("--disable-crash-handler");
+	}
+
 	Rect2 screen_rect;
 	screen_rect.position = OS::get_singleton()->get_screen_position(screen);
 	screen_rect.size = OS::get_singleton()->get_screen_size(screen);

editor/project_manager.cpp

@@ -948,6 +948,10 @@ void ProjectManager::_open_project_confirm() {
 
 		args.push_back("--editor");
 
+		if (OS::get_singleton()->is_disable_crash_handler()) {
+			args.push_back("--disable-crash-handler");
+		}
+
 		String exec = OS::get_singleton()->get_executable_path();
 
 		OS::ProcessID pid = 0;
@@ -999,6 +1003,10 @@ void ProjectManager::_run_project_confirm() {
 		args.push_back("--path");
 		args.push_back(path);
 
+		if (OS::get_singleton()->is_disable_crash_handler()) {
+			args.push_back("--disable-crash-handler");
+		}
+
 		String exec = OS::get_singleton()->get_executable_path();
 
 		OS::ProcessID pid = 0;

main/main.cpp

@@ -194,6 +194,7 @@ void Main::print_help(const char *p_binary) {
 	OS::get_singleton()->print("  --frame-delay <ms>               Simulate high CPU load (delay each frame by <ms> milliseconds).\n");
 	OS::get_singleton()->print("  --time-scale <scale>             Force time scale (higher values are faster, 1.0 is normal speed).\n");
 	OS::get_singleton()->print("  --disable-render-loop            Disable render loop so rendering only occurs when called explicitly from script.\n");
+	OS::get_singleton()->print("  --disable-crash-handler          Disable crash handler when supported by the platform code.\n");
 	OS::get_singleton()->print("  --fixed-fps <fps>                Forces a fixed ratio between process and fixed_process timing, for use when precision is required, or when rendering to video files. Setting this will disable real-time syncronization, so that run speed is only capped by performance\n");
 	OS::get_singleton()->print("\n");
 
@@ -247,6 +248,8 @@ Error Main::setup(const char *execpath, int argc, char *argv[], bool p_second_ph
 	performance = memnew(Performance);
 	globals->add_singleton(ProjectSettings::Singleton("Performance", performance));
 
+	GLOBAL_DEF("debug/settings/backtrace/message", String("Please include this when reporting the bug on https://github.com/godotengine/godot/issues"));
+
 	MAIN_PRINT("Main: Parse CMDLine");
 
 	/* argument parsing and main creation */
@@ -582,6 +585,8 @@ Error Main::setup(const char *execpath, int argc, char *argv[], bool p_second_ph
 				OS::get_singleton()->print("Missing fixed-fps argument, aborting.\n");
 				goto error;
 			}
+		} else if (I->get() == "--disable-crash-handler") {
+			OS::get_singleton()->disable_crash_handler();
 		} else {
 
 			//test for game path

platform/osx/SCsub

@@ -3,6 +3,7 @@
 Import('env')
 
 files = [
+    'crash_handler_osx.mm',
     'os_osx.mm',
     'godot_main_osx.mm',
     'audio_driver_osx.cpp',
@@ -12,4 +13,8 @@ files = [
     'power_osx.cpp',
 ]
 
-env.Program('#bin/godot', files)
+prog = env.Program('#bin/godot', files)
+if (env['target'] == "debug" or env['target'] == "release_debug"):
+    # Build the .dSYM file for atos
+    action = "dsymutil " + File(prog)[0].path + " -o " + File(prog)[0].path + ".dSYM"
+    env.AddPostAction(prog, action)

platform/osx/crash_handler_osx.h

@@ -0,0 +1,47 @@
+/*************************************************************************/
+/*  crash_handler_osx.h                                                  */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* 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.                */
+/*************************************************************************/
+#ifndef CRASH_HANDLER_OSX_H
+#define CRASH_HANDLER_OSX_H
+
+class CrashHandler {
+
+	bool disabled;
+
+public:
+	void initialize();
+
+	void disable();
+	bool is_disabled() const { return disabled; };
+
+	CrashHandler();
+	~CrashHandler();
+};
+
+#endif

platform/osx/crash_handler_osx.mm

@@ -0,0 +1,178 @@
+/*************************************************************************/
+/*  crash_handler_osx.mm                                                 */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* 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 "main/main.h"
+#include "os_osx.h"
+
+#include <string.h>
+#include <unistd.h>
+
+// Note: Dump backtrace in 32bit mode is getting a bus error on the fgets by the ->execute, so enable only on 64bit
+#if defined(DEBUG_ENABLED) && defined(__x86_64__)
+#define CRASH_HANDLER_ENABLED 1
+#endif
+
+#ifdef CRASH_HANDLER_ENABLED
+#include <cxxabi.h>
+#include <dlfcn.h>
+#include <execinfo.h>
+#include <signal.h>
+
+#include <mach-o/dyld.h>
+#include <mach-o/getsect.h>
+
+#ifdef __x86_64__
+static uint64_t load_address() {
+	const struct segment_command_64 *cmd = getsegbyname("__TEXT");
+#else
+static uint32_t load_address() {
+	const struct segment_command *cmd = getsegbyname("__TEXT");
+#endif
+	char full_path[1024];
+	uint32_t size = sizeof(full_path);
+
+	if (cmd && !_NSGetExecutablePath(full_path, &size)) {
+		uint32_t dyld_count = _dyld_image_count();
+		for (uint32_t i = 0; i < dyld_count; i++) {
+			const char *image_name = _dyld_get_image_name(i);
+			if (image_name && strncmp(image_name, full_path, 1024) == 0) {
+				return cmd->vmaddr + _dyld_get_image_vmaddr_slide(i);
+			}
+		}
+	}
+
+	return 0;
+}
+
+static void handle_crash(int sig) {
+	if (OS::get_singleton() == NULL)
+		return;
+
+	void *bt_buffer[256];
+	size_t size = backtrace(bt_buffer, 256);
+	String _execpath = OS::get_singleton()->get_executable_path();
+	String msg = GLOBAL_GET("debug/settings/backtrace/message");
+
+	// Dump the backtrace to stderr with a message to the user
+	fprintf(stderr, "%s: Program crashed with signal %d\n", __FUNCTION__, sig);
+	fprintf(stderr, "Dumping the backtrace. %ls\n", msg.c_str());
+	char **strings = backtrace_symbols(bt_buffer, size);
+	if (strings) {
+		void *load_addr = (void *)load_address();
+
+		for (int i = 1; i < size; i++) {
+			char fname[1024];
+			Dl_info info;
+
+			snprintf(fname, 1024, "%s", strings[i]);
+
+			// Try to demangle the function name to provide a more readable one
+			if (dladdr(bt_buffer[i], &info) && info.dli_sname) {
+				if (info.dli_sname[0] == '_') {
+					int status;
+					char *demangled = abi::__cxa_demangle(info.dli_sname, NULL, 0, &status);
+
+					if (status == 0 && demangled) {
+						snprintf(fname, 1024, "%s", demangled);
+					}
+
+					if (demangled)
+						free(demangled);
+				}
+			}
+
+			String output = fname;
+
+			// Try to get the file/line number using atos
+			if (bt_buffer[i] > (void *)0x0 && OS::get_singleton()) {
+				List<String> args;
+				char str[1024];
+
+				args.push_back("-o");
+				args.push_back(_execpath);
+				args.push_back("-arch");
+#ifdef __x86_64__
+				args.push_back("x86_64");
+#else
+				args.push_back("i386");
+#endif
+				args.push_back("-l");
+				snprintf(str, 1024, "%p", load_addr);
+				args.push_back(str);
+				snprintf(str, 1024, "%p", bt_buffer[i]);
+				args.push_back(str);
+
+				int ret;
+				String out = "";
+				Error err = OS::get_singleton()->execute(String("atos"), args, true, NULL, &out, &ret);
+				if (err == OK && out.substr(0, 2) != "0x") {
+					out.erase(out.length() - 1, 1);
+					output = out;
+				}
+			}
+
+			fprintf(stderr, "[%d] %ls\n", i, output.c_str());
+		}
+
+		free(strings);
+	}
+	fprintf(stderr, "-- END OF BACKTRACE --\n");
+
+	// Abort to pass the error to the OS
+	abort();
+}
+#endif
+
+CrashHandler::CrashHandler() {
+	disabled = false;
+}
+
+CrashHandler::~CrashHandler() {
+}
+
+void CrashHandler::disable() {
+	if (disabled)
+		return;
+
+#ifdef CRASH_HANDLER_ENABLED
+	signal(SIGSEGV, NULL);
+	signal(SIGFPE, NULL);
+	signal(SIGILL, NULL);
+#endif
+
+	disabled = true;
+}
+
+void CrashHandler::initialize() {
+#ifdef CRASH_HANDLER_ENABLED
+	signal(SIGSEGV, handle_crash);
+	signal(SIGFPE, handle_crash);
+	signal(SIGILL, handle_crash);
+#endif
+}

platform/osx/godot_main_osx.mm

@@ -35,7 +35,6 @@
 #include <unistd.h>
 
 int main(int argc, char **argv) {
-
 	int first_arg = 1;
 	const char *dbg_arg = "-NSDocumentRevisionsDebugMode";
 	printf("arguments\n");

platform/osx/os_osx.h

@@ -30,6 +30,7 @@
 #ifndef OS_OSX_H
 #define OS_OSX_H
 
+#include "crash_handler_osx.h"
 #include "drivers/alsa/audio_driver_alsa.h"
 #include "drivers/rtaudio/audio_driver_rtaudio.h"
 #include "drivers/unix/os_unix.h"
@@ -110,6 +111,8 @@ class OS_OSX : public OS_Unix {
 
 	power_osx *power_manager;
 
+	CrashHandler crash_handler;
+
 	float _mouse_scale(float p_scale) {
 		if (display_scale > 1.0)
 			return p_scale;
@@ -224,6 +227,9 @@ class OS_OSX : public OS_Unix {
 	void set_mouse_mode(MouseMode p_mode);
 	MouseMode get_mouse_mode() const;
 
+	void disable_crash_handler();
+	bool is_disable_crash_handler() const;
+
 	OS_OSX();
 };
 

platform/osx/os_osx.mm

@@ -910,6 +910,8 @@ - (BOOL)canBecomeKeyWindow {
 
 void OS_OSX::initialize_core() {
 
+	crash_handler.initialize();
+
 	OS_Unix::initialize_core();
 
 	DirAccess::make_default<DirAccessOSX>(DirAccess::ACCESS_RESOURCES);
@@ -2022,3 +2024,11 @@ static void keyboardLayoutChanged(CFNotificationCenterRef center, void *observer
 bool OS_OSX::_check_internal_feature_support(const String &p_feature) {
 	return p_feature == "pc" || p_feature == "s3tc";
 }
+
+void OS_OSX::disable_crash_handler() {
+	crash_handler.disable();
+}
+
+bool OS_OSX::is_disable_crash_handler() const {
+	return crash_handler.is_disabled();
+}

platform/windows/SCsub

@@ -5,14 +5,15 @@ Import('env')
 
 common_win = [
     "context_gl_win.cpp",
+    "crash_handler_win.cpp",
     "os_windows.cpp",
     "ctxgl_procaddr.cpp",
     "key_mapping_win.cpp",
     "tcp_server_winsock.cpp",
     "packet_peer_udp_winsock.cpp",
     "stream_peer_winsock.cpp",
     "joypad.cpp",
-	"power_windows.cpp",
+    "power_windows.cpp",
 ]
 
 restarget = "godot_res" + env["OBJSUFFIX"]