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** General Public License version 2.1 as published by the Free Software

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****************************************************************************/

/*************************************************************************

 *

 * 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;

#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);

}