summaryrefslogtreecommitdiffstats
path: root/src/corelib/kernel/qcrashhandler.cpp
blob: 979e215997a87ed4741ddc817f0b2dc595b914e3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this
** file. Please review the following information to ensure the GNU Lesser
** General Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU General
** Public License version 3.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of this
** file. Please review the following information to ensure the GNU General
** Public License version 3.0 requirements will be met:
** http://www.gnu.org/copyleft/gpl.html.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

/*************************************************************************
 *
 * stacktrace.c 1.2 1998/12/21
 *
 * Copyright (c) 1998 by Bjorn Reese <breese@imada.ou.dk>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE AUTHORS AND
 * CONTRIBUTORS ACCEPT NO RESPONSIBILITY IN ANY CONCEIVABLE MANNER.
 *
 ************************************************************************/

#include "qplatformdefs.h"
#include "private/qcrashhandler_p.h"
#include "qbytearray.h" // for qvsnprintf()

#ifndef QT_NO_CRASHHANDLER

#include <stdio.h>
#include <signal.h>
#include <stdlib.h>

QT_BEGIN_NAMESPACE

QtCrashHandler QSegfaultHandler::callback = 0;

#if defined(__GLIBC__) && (__GLIBC__ >= 2) && !defined(__UCLIBC__) && !defined(QT_LINUXBASE)
QT_BEGIN_INCLUDE_NAMESPACE
# include "qstring.h"
# include <execinfo.h>
QT_END_INCLUDE_NAMESPACE

static void print_backtrace(FILE *outb)
{
    void *stack[128];
    int stack_size = backtrace(stack, sizeof(stack) / sizeof(void *));
    char **stack_symbols = backtrace_symbols(stack, stack_size);
    fprintf(outb, "Stack [%d]:\n", stack_size);
    if(FILE *cppfilt = popen("c++filt", "rw")) {
        dup2(fileno(outb), fileno(cppfilt));
        for(int i = stack_size-1; i>=0; --i)
            fwrite(stack_symbols[i], 1, strlen(stack_symbols[i]), cppfilt);
        pclose(cppfilt);
    } else {
        for(int i = stack_size-1; i>=0; --i)
            fprintf(outb, "#%d  %p [%s]\n", i, stack[i], stack_symbols[i]);
    }
}
static void init_backtrace(char **, int)
{
}

#else /* Don't use the GLIBC callback */
/* Code sourced from: */
QT_BEGIN_INCLUDE_NAMESPACE
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/wait.h>
#if defined(Q_OS_IRIX) && defined(USE_LIBEXC)
# include <libexc.h>
#endif
QT_END_INCLUDE_NAMESPACE


static char *globalProgName = NULL;
static bool backtrace_command(FILE *outb, const char *format, ...)
{

    bool ret = false;
    char buffer[50];

    /*
     * Please note that vsnprintf() is not ASync safe (ie. cannot safely
     * be used from a signal handler.) If this proves to be a problem
     * then the cmd string can be built by more basic functions such as
     * strcpy, strcat, and a home-made integer-to-ascii function.
     */
    va_list args;
    char cmd[512];
    va_start(args, format);
    qvsnprintf(cmd, 512, format, args);
    va_end(args);

    char *foo = cmd;
#if 0
    foo = "echo hi";
#endif
    if(FILE *inb = popen(foo, "r")) {
        while(!feof(inb)) {
            int len = fread(buffer, 1, sizeof(buffer), inb);
            if(!len)
                break;
            if(!ret) {
                fwrite("Output from ", 1, strlen("Output from "), outb);
                strtok(cmd, " ");
                fwrite(cmd, 1, strlen(cmd), outb);
                fwrite("\n", 1, 1, outb);
                ret = true;
            }
            fwrite(buffer, 1, len, outb);
        }
        fclose(inb);
    }
    return ret;
}

static void init_backtrace(char **argv, int argc)
{
    if(argc >= 1)
        globalProgName = argv[0];
}

static void print_backtrace(FILE *outb)
{
    /*
     * In general dbx seems to do a better job than gdb.
     *
     * Different dbx implementations require different flags/commands.
     */
#if defined(Q_OS_AIX)
    if(backtrace_command(outb, "dbx -a %d 2>/dev/null <<EOF\n"
                         "where\n"
                         "detach\n"
                         "EOF\n",
                         (int)getpid()))
        return;
    if(backtrace_command(outb, "gdb -q %s %d 2>/dev/null <<EOF\n"
                         "set prompt\n"
                         "where\n"
                         "detach\n"
                         "quit\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
#elif defined(Q_OS_FREEBSD)
    /*
     * FreeBSD insists on sending a SIGSTOP to the process we
     * attach to, so we let the debugger send a SIGCONT to that
     * process after we have detached.
     */
    if(backtrace_command(outb, "gdb -q %s %d 2>/dev/null <<EOF\n"
                         "set prompt\n"
                         "where\n"
                         "detach\n"
                         "shell kill -CONT %d\n"
                         "quit\n"
                         "EOF\n",
                         globalProgName, (int)getpid(), (int)getpid()))
        return;
#elif defined(Q_OS_HPUX)
    /*
     * HP decided to call their debugger xdb.
     *
     * This does not seem to work properly yet. The debugger says
     * "Note: Stack traces may not be possible until you are
     *  stopped in user code." on HP-UX 09.01
     *
     * -L = line-oriented interface.
     * "T [depth]" gives a stacktrace with local variables.
     * The final "y" is confirmation to the quit command.
     */
    if(backtrace_command(outb, "xdb -P %d -L %s 2>&1 <<EOF\n"
                         "T 50\n"
                         "q\ny\n"
                         "EOF\n",
                         (int)getpid(), globalProgName))
        return;
    if(backtrace_command(outb, "gdb -q %s %d 2>/dev/null <<EOF\n"
                         "set prompt\n"
                         "where\n"
                         "detach\n"
                         "quit\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
#elif defined(Q_OS_IRIX)
    /*
     * "set $page=0" drops hold mode
     * "dump ." displays the contents of the variables
     */
    if(backtrace_command(outb, "dbx -p %d 2>/dev/null <<EOF\n"
                         "set \\$page=0\n"
                         "where\n"
# if !defined(__GNUC__)
                         /* gcc does not generate this information */
                         "dump .\n"
# endif
                         "detach\n"
                         "EOF\n",
                         (int)getpid()))
        return;

# if defined(USE_LIBEXC)
    if(trace_back_stack_and_print())
        return;
# endif
    if(backtrace_command(outb, "gdb -q %s %d 2>/dev/null <<EOF\n"
                         "set prompt\n"
                         "where\n"
                         "echo ---\\n\n"
                         "frame 5\n"      /* Skip signal handler frames */
                         "set \\$x = 50\n"
                         "while (\\$x)\n" /* Print local variables for each frame */
                         "info locals\n"
                         "up\n"
                         "set \\$x--\n"
                         "end\n"
                         "echo ---\\n\n"
                         "detach\n"
                         "quit\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
#elif defined(Q_OS_OSF)
    if(backtrace_command(outb, "dbx -pid %d %s 2>/dev/null <<EOF\n"
                         "where\n"
                         "detach\n"
                         "quit\n"
                         "EOF\n",
                         (int)getpid(), globalProgName))
        return;
    if(backtrace_command(outb, "gdb -q %s %d 2>/dev/null <<EOF\n"
                         "set prompt\n"
                         "where\n"
                         "detach\n"
                         "quit\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
#elif defined(Q_OS_SCO)
    /*
     * SCO OpenServer dbx is like a catch-22. The 'detach' command
     * depends on whether ptrace(S) support detaching or not. If it
     * is supported then 'detach' must be used, otherwise the process
     * will be killed upon dbx exit. If it isn't supported then 'detach'
     * will cause the process to be killed. We do not want it to be
     * killed.
     *
     * Out of two evils, the omission of 'detach' was chosen because
     * it worked on our system.
     */
    if(backtrace_command(outb, "dbx %s %d 2>/dev/null <<EOF\n"
                         "where\n"
                         "quit\nEOF\n",
                         globalProgName, (int)getpid()))
        return;
    if(backtrace_command(outb, "gdb -q %s %d 2>/dev/null <<EOF\n"
                         "set prompt\n"
                         "where\n"
                         "detach\n"
                         "quit\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
#elif defined(Q_OS_SOLARIS)
    if(backtrace_command(outb, "dbx %s %d 2>/dev/null <<EOF\n"
                         "where\n"
                         "detach\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
    if(backtrace_command(outb, "gdb -q %s %d 2>/dev/null <<EOF\n"
                         "set prompt\n"
                         "where\n"
                         "echo ---\\n\n"
                         "frame 5\n"      /* Skip signal handler frames */
                         "set \\$x = 50\n"
                         "while (\\$x)\n" /* Print local variables for each frame */
                         "info locals\n"
                         "up\n"
                         "set \\$x--\n"
                         "end\n"
                         "echo ---\\n\n"
                         "detach\n"
                         "quit\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
    if(backtrace_command(outb, "/usr/proc/bin/pstack %d",
                         (int)getpid()))
        return;
    /*
     * Other Unices (AIX, HPUX, SCO) also have adb, but
     * they seem unable to attach to a running process.)
     */
    if(backtrace_command(outb, "adb %s 2>&1 <<EOF\n"
                         "0t%d:A\n" /* Attach to pid */
                         "\\$c\n"   /* print stacktrace */
                         ":R\n"     /* Detach */
                         "\\$q\n"   /* Quit */
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
#elif defined(Q_OS_INTEGRITY)
    /* abort */
    CheckSuccess(Failure);
#else /* All other platforms */
    /*
     * TODO: SCO/UnixWare 7 must be something like (not tested)
     *  debug -i c <pid> <<EOF\nstack -f 4\nquit\nEOF\n
     */
# if !defined(__GNUC__)
    if(backtrace_command(outb, "dbx %s %d 2>/dev/null <<EOF\n"
                         "where\n"
                         "detach\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
# endif
    if(backtrace_command(outb, "gdb -q %s %d 2>/dev/null <<EOF\n"
                         "set prompt\n"
                         "where\n"
#if 0
                         "echo ---\\n\n"
                         "frame 4\n"
                         "set \\$x = 50\n"
                         "while (\\$x)\n"
                         "info locals\n"
                         "up\n"
                         "set \\$x--\n"
                         "end\n"
                         "echo ---\\n\n"
#endif
                         "detach\n"
                         "quit\n"
                         "EOF\n",
                         globalProgName, (int)getpid()))
        return;
#endif
    const char debug_err[] = "No debugger found\n";
    fwrite(debug_err, strlen(debug_err), 1, outb);
}
/* end of copied code */
#endif


void qt_signal_handler(int sig)
{
    signal(sig, SIG_DFL);
    if(QSegfaultHandler::callback) {
        (*QSegfaultHandler::callback)();
        _exit(1);
    }
    FILE *outb = stderr;
    if(char *crash_loc = ::getenv("QT_CRASH_OUTPUT")) {
        if(FILE *new_outb = fopen(crash_loc, "w")) {
            fprintf(stderr, "Crash (backtrace written to %s)!!!\n", crash_loc);
            outb = new_outb;
        }
    } else {
        fprintf(outb, "Crash!!!\n");
    }
    print_backtrace(outb);
    if(outb != stderr)
        fclose(outb);
    _exit(1);
}


void
QSegfaultHandler::initialize(char **argv, int argc)
{
    init_backtrace(argv, argc);

    struct sigaction SignalAction;
    SignalAction.sa_flags = 0;
    SignalAction.sa_handler = qt_signal_handler;
    sigemptyset(&SignalAction.sa_mask);
    sigaction(SIGSEGV, &SignalAction, NULL);
    sigaction(SIGBUS, &SignalAction, NULL);
}

QT_END_NAMESPACE

#endif // QT_NO_CRASHHANDLER