1 /*
2 * This file is part of OpenTTD.
3 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
4 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
5 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
6 */
7
8 /** @file crashlog_unix.cpp Unix crash log handler */
9
10 #include "../../stdafx.h"
11 #include "../../crashlog.h"
12 #include "../../string_func.h"
13 #include "../../gamelog.h"
14 #include "../../saveload/saveload.h"
15
16 #include <errno.h>
17 #include <signal.h>
18 #include <sys/utsname.h>
19
20 #if defined(__GLIBC__)
21 /* Execinfo (and thus making stacktraces) is a GNU extension */
22 # include <execinfo.h>
23 #elif defined(SUNOS)
24 # include <ucontext.h>
25 # include <dlfcn.h>
26 #endif
27
28 #if defined(__NetBSD__)
29 #include <unistd.h>
30 #endif
31
32 #include "../../safeguards.h"
33
34 /**
35 * Unix implementation for the crash logger.
36 */
37 class CrashLogUnix : public CrashLog {
38 /** Signal that has been thrown. */
39 int signum;
40
LogOSVersion(char * buffer,const char * last) const41 char *LogOSVersion(char *buffer, const char *last) const override
42 {
43 struct utsname name;
44 if (uname(&name) < 0) {
45 return buffer + seprintf(buffer, last, "Could not get OS version: %s\n", strerror(errno));
46 }
47
48 return buffer + seprintf(buffer, last,
49 "Operating system:\n"
50 " Name: %s\n"
51 " Release: %s\n"
52 " Version: %s\n"
53 " Machine: %s\n",
54 name.sysname,
55 name.release,
56 name.version,
57 name.machine
58 );
59 }
60
LogError(char * buffer,const char * last,const char * message) const61 char *LogError(char *buffer, const char *last, const char *message) const override
62 {
63 return buffer + seprintf(buffer, last,
64 "Crash reason:\n"
65 " Signal: %s (%d)\n"
66 " Message: %s\n\n",
67 strsignal(this->signum),
68 this->signum,
69 message == nullptr ? "<none>" : message
70 );
71 }
72
73 #if defined(SUNOS)
74 /** Data needed while walking up the stack */
75 struct StackWalkerParams {
76 char **bufptr; ///< Buffer
77 const char *last; ///< End of buffer
78 int counter; ///< We are at counter-th stack level
79 };
80
81 /**
82 * Callback used while walking up the stack.
83 * @param pc program counter
84 * @param sig 'active' signal (unused)
85 * @param params parameters
86 * @return always 0, continue walking up the stack
87 */
SunOSStackWalker(uintptr_t pc,int sig,void * params)88 static int SunOSStackWalker(uintptr_t pc, int sig, void *params)
89 {
90 StackWalkerParams *wp = (StackWalkerParams *)params;
91
92 /* Resolve program counter to file and nearest symbol (if possible) */
93 Dl_info dli;
94 if (dladdr((void *)pc, &dli) != 0) {
95 *wp->bufptr += seprintf(*wp->bufptr, wp->last, " [%02i] %s(%s+0x%x) [0x%x]\n",
96 wp->counter, dli.dli_fname, dli.dli_sname, (int)((byte *)pc - (byte *)dli.dli_saddr), (uint)pc);
97 } else {
98 *wp->bufptr += seprintf(*wp->bufptr, wp->last, " [%02i] [0x%x]\n", wp->counter, (uint)pc);
99 }
100 wp->counter++;
101
102 return 0;
103 }
104 #endif
105
LogStacktrace(char * buffer,const char * last) const106 char *LogStacktrace(char *buffer, const char *last) const override
107 {
108 buffer += seprintf(buffer, last, "Stacktrace:\n");
109 #if defined(__GLIBC__)
110 void *trace[64];
111 int trace_size = backtrace(trace, lengthof(trace));
112
113 char **messages = backtrace_symbols(trace, trace_size);
114 for (int i = 0; i < trace_size; i++) {
115 buffer += seprintf(buffer, last, " [%02i] %s\n", i, messages[i]);
116 }
117 free(messages);
118 #elif defined(SUNOS)
119 ucontext_t uc;
120 if (getcontext(&uc) != 0) {
121 buffer += seprintf(buffer, last, " getcontext() failed\n\n");
122 return buffer;
123 }
124
125 StackWalkerParams wp = { &buffer, last, 0 };
126 walkcontext(&uc, &CrashLogUnix::SunOSStackWalker, &wp);
127 #else
128 buffer += seprintf(buffer, last, " Not supported.\n");
129 #endif
130 return buffer + seprintf(buffer, last, "\n");
131 }
132 public:
133 /**
134 * A crash log is always generated by signal.
135 * @param signum the signal that was caused by the crash.
136 */
CrashLogUnix(int signum)137 CrashLogUnix(int signum) :
138 signum(signum)
139 {
140 }
141 };
142
143 /** The signals we want our crash handler to handle. */
144 static const int _signals_to_handle[] = { SIGSEGV, SIGABRT, SIGFPE, SIGBUS, SIGILL };
145
146 /**
147 * Entry point for the crash handler.
148 * @note Not static so it shows up in the backtrace.
149 * @param signum the signal that caused us to crash.
150 */
HandleCrash(int signum)151 static void CDECL HandleCrash(int signum)
152 {
153 /* Disable all handling of signals by us, so we don't go into infinite loops. */
154 for (const int *i = _signals_to_handle; i != endof(_signals_to_handle); i++) {
155 signal(*i, SIG_DFL);
156 }
157
158 if (GamelogTestEmergency()) {
159 printf("A serious fault condition occurred in the game. The game will shut down.\n");
160 printf("As you loaded an emergency savegame no crash information will be generated.\n");
161 abort();
162 }
163
164 if (SaveloadCrashWithMissingNewGRFs()) {
165 printf("A serious fault condition occurred in the game. The game will shut down.\n");
166 printf("As you loaded an savegame for which you do not have the required NewGRFs\n");
167 printf("no crash information will be generated.\n");
168 abort();
169 }
170
171 CrashLogUnix log(signum);
172 log.MakeCrashLog();
173
174 CrashLog::AfterCrashLogCleanup();
175 abort();
176 }
177
InitialiseCrashLog()178 /* static */ void CrashLog::InitialiseCrashLog()
179 {
180 for (const int *i = _signals_to_handle; i != endof(_signals_to_handle); i++) {
181 signal(*i, HandleCrash);
182 }
183 }
184
InitThread()185 /* static */ void CrashLog::InitThread()
186 {
187 }
188