1/**************************************************************************/
2/* crash_handler_linuxbsd.cpp */
3/**************************************************************************/
4/* This file is part of: */
5/* GODOT ENGINE */
6/* https://godotengine.org */
7/**************************************************************************/
8/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
9/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
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28/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
29/**************************************************************************/
30
31#include "crash_handler_linuxbsd.h"
32
33#include "core/config/project_settings.h"
34#include "core/os/os.h"
35#include "core/string/print_string.h"
36#include "core/version.h"
37#include "main/main.h"
38
39#ifdef DEBUG_ENABLED
40#define CRASH_HANDLER_ENABLED 1
41#endif
42
43#ifdef CRASH_HANDLER_ENABLED
44#include <cxxabi.h>
45#include <dlfcn.h>
46#include <execinfo.h>
47#include <link.h>
48#include <signal.h>
49#include <stdlib.h>
50
51static void handle_crash(int sig) {
52 if (OS::get_singleton() == nullptr) {
53 abort();
54 }
55
56 void *bt_buffer[256];
57 size_t size = backtrace(bt_buffer, 256);
58 String _execpath = OS::get_singleton()->get_executable_path();
59
60 String msg;
61 const ProjectSettings *proj_settings = ProjectSettings::get_singleton();
62 if (proj_settings) {
63 msg = proj_settings->get("debug/settings/crash_handler/message");
64 }
65
66 // Tell MainLoop about the crash. This can be handled by users too in Node.
67 if (OS::get_singleton()->get_main_loop()) {
68 OS::get_singleton()->get_main_loop()->notification(MainLoop::NOTIFICATION_CRASH);
69 }
70
71 // Dump the backtrace to stderr with a message to the user
72 print_error("\n================================================================");
73 print_error(vformat("%s: Program crashed with signal %d", __FUNCTION__, sig));
74
75 // Print the engine version just before, so that people are reminded to include the version in backtrace reports.
76 if (String(VERSION_HASH).is_empty()) {
77 print_error(vformat("Engine version: %s", VERSION_FULL_NAME));
78 } else {
79 print_error(vformat("Engine version: %s (%s)", VERSION_FULL_NAME, VERSION_HASH));
80 }
81 print_error(vformat("Dumping the backtrace. %s", msg));
82 char **strings = backtrace_symbols(bt_buffer, size);
83 // PIE executable relocation, zero for non-PIE executables
84#ifdef __GLIBC__
85 // This is a glibc only thing apparently.
86 uintptr_t relocation = _r_debug.r_map->l_addr;
87#else
88 // Non glibc systems apparently don't give PIE relocation info.
89 uintptr_t relocation = 0;
90#endif //__GLIBC__
91 if (strings) {
92 List<String> args;
93 for (size_t i = 0; i < size; i++) {
94 char str[1024];
95 snprintf(str, 1024, "%p", (void *)((uintptr_t)bt_buffer[i] - relocation));
96 args.push_back(str);
97 }
98 args.push_back("-e");
99 args.push_back(_execpath);
100
101 // Try to get the file/line number using addr2line
102 int ret;
103 String output = "";
104 Error err = OS::get_singleton()->execute(String("addr2line"), args, &output, &ret);
105 Vector<String> addr2line_results;
106 if (err == OK) {
107 addr2line_results = output.substr(0, output.length() - 1).split("\n", false);
108 }
109
110 for (size_t i = 1; i < size; i++) {
111 char fname[1024];
112 Dl_info info;
113
114 snprintf(fname, 1024, "%s", strings[i]);
115
116 // Try to demangle the function name to provide a more readable one
117 if (dladdr(bt_buffer[i], &info) && info.dli_sname) {
118 if (info.dli_sname[0] == '_') {
119 int status = 0;
120 char *demangled = abi::__cxa_demangle(info.dli_sname, nullptr, nullptr, &status);
121
122 if (status == 0 && demangled) {
123 snprintf(fname, 1024, "%s", demangled);
124 }
125
126 if (demangled) {
127 free(demangled);
128 }
129 }
130 }
131
132 print_error(vformat("[%d] %s (%s)", (int64_t)i, fname, err == OK ? addr2line_results[i] : ""));
133 }
134
135 free(strings);
136 }
137 print_error("-- END OF BACKTRACE --");
138 print_error("================================================================");
139
140 // Abort to pass the error to the OS
141 abort();
142}
143#endif
144
145CrashHandler::CrashHandler() {
146 disabled = false;
147}
148
149CrashHandler::~CrashHandler() {
150 disable();
151}
152
153void CrashHandler::disable() {
154 if (disabled) {
155 return;
156 }
157
158#ifdef CRASH_HANDLER_ENABLED
159 signal(SIGSEGV, nullptr);
160 signal(SIGFPE, nullptr);
161 signal(SIGILL, nullptr);
162#endif
163
164 disabled = true;
165}
166
167void CrashHandler::initialize() {
168#ifdef CRASH_HANDLER_ENABLED
169 signal(SIGSEGV, handle_crash);
170 signal(SIGFPE, handle_crash);
171 signal(SIGILL, handle_crash);
172#endif
173}
174