/*
 * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2005 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart, 
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * Copyright (c) 2006      Sun Microsystems, Inc.  All rights reserved.
 * $COPYRIGHT$
 * 
 * Additional copyrights may follow
 * 
 * $HEADER$
 */

#include "opal_config.h"

#include <stdio.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef HAVE_STRING_H
#include <string.h>
#endif

#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif

#include "opal/util/stacktrace.h"
#include "opal/mca/base/mca_base_param.h"
#include "opal/mca/backtrace/backtrace.h"
#include "opal/constants.h"

#ifndef _NSIG
#define _NSIG 32
#endif

#define HOSTFORMAT "[%s:%05d] "

static char stacktrace_hostname[64];

/**
 * This function is being called as a signal-handler in response
 * to a user-specified signal (e.g. SIGFPE or SIGSEGV).
 * For Linux/Glibc, it then uses backtrace and backtrace_symbols
 * to figure the current stack and then prints that out to stdout.
 * Where available, the BSD libexecinfo is used to provide Linux/Glibc
 * compatible backtrace and backtrace_symbols functions.
 * Yes, printf and malloc are not signal-safe per se, but should be 
 * on Linux?
 *
 *  @param signo with the signal number raised 
 *  @param info with information regarding the reason/send of the signal
 *  @param p 
 *
 * FIXME: Should distinguish for systems, which don't have siginfo...
 */
#if OMPI_WANT_PRETTY_PRINT_STACKTRACE && ! defined(__WINDOWS__)
static void opal_show_stackframe (int signo, siginfo_t * info, void * p)
{   
    char print_buffer[1024];
    char * tmp = print_buffer;
    int size = sizeof (print_buffer);
    int ret, traces_size;
    char *si_code_str = "";
    char **traces;

    /* write out the footer information */
    memset (print_buffer, 0, sizeof (print_buffer));
    ret = snprintf(print_buffer, sizeof(print_buffer),
                   HOSTFORMAT "*** Process received signal ***\n",
                   stacktrace_hostname, getpid());
    write(fileno(stderr), print_buffer, ret);
    fflush(stderr);


    /*
     * Yes, we are doing printf inside a signal-handler.
     * However, backtrace itself calls malloc (which may not be signal-safe,
     * under linux, printf and malloc are)
     *
     * We could use backtrace_symbols_fd and write directly into an
     * filedescriptor, however, without formatting -- also this fd 
     * should be opened in a sensible way...
     */
    memset (print_buffer, 0, sizeof (print_buffer));

#ifdef HAVE_STRSIGNAL
    ret = snprintf (tmp, size, HOSTFORMAT "Signal: %s (%d)\n", 
                    stacktrace_hostname, getpid(), strsignal(signo), signo);
#else
    ret = snprintf (tmp, size, HOSTFORMAT "Signal: %d\n", 
                    stacktrace_hostname, getpid(), signo);
#endif
    size -= ret;
    tmp += ret;

    if (NULL != info) {
        switch (signo)
        {
        case SIGILL:
            switch (info->si_code)
            {
#ifdef ILL_ILLOPC
            case ILL_ILLOPC: si_code_str = "Illegal opcode"; break;
#endif
#ifdef ILL_ILLOPN
            case ILL_ILLOPN: si_code_str = "Illegal operand"; break;
#endif
#ifdef ILL_ILLADR
            case ILL_ILLADR: si_code_str = "Illegal addressing mode"; break;
#endif
#ifdef ILL_ILLTRP
            case ILL_ILLTRP: si_code_str = "Illegal trap"; break;
#endif
#ifdef ILL_PRVOPC
            case ILL_PRVOPC: si_code_str = "Privileged opcode"; break;
#endif
#ifdef ILL_PRVREG
            case ILL_PRVREG: si_code_str = "Privileged register"; break;
#endif
#ifdef ILL_COPROC
            case ILL_COPROC: si_code_str = "Coprocessor error"; break;
#endif
#ifdef ILL_BADSTK
            case ILL_BADSTK: si_code_str = "Internal stack error"; break;
#endif
            }
            break;
        case SIGFPE:
            switch (info->si_code)
            {
#ifdef FPE_INTDIV
            case FPE_INTDIV: si_code_str = "Integer divide-by-zero"; break;
#endif
#ifdef FPE_INTOVF
            case FPE_INTOVF: si_code_str = "Integer overflow"; break;
#endif
            case FPE_FLTDIV: si_code_str = "Floating point divide-by-zero"; break;
            case FPE_FLTOVF: si_code_str = "Floating point overflow"; break;
            case FPE_FLTUND: si_code_str = "Floating point underflow"; break;
            case FPE_FLTRES: si_code_str = "Floating point inexact result"; break;
#ifdef FBE_FLTINV
            case FPE_FLTINV: si_code_str = "Invalid floating point operation"; break;
#endif
#ifdef FPE_FLTSUB
            case FPE_FLTSUB: si_code_str = "Subscript out of range"; break;
#endif
            }
            break;
        case SIGSEGV:
            switch (info->si_code)
            {
#ifdef SEGV_MAPERR
            case SEGV_MAPERR: si_code_str = "Address not mapped"; break;
#endif
#ifdef SEGV_ACCERR
            case SEGV_ACCERR: si_code_str = "Invalid permissions"; break;
#endif
            }
            break;
        case SIGBUS:
            switch (info->si_code)
            {
#ifdef BUS_ADRALN
            case BUS_ADRALN: si_code_str = "Invalid address alignment"; break;
#endif
#ifdef BUSADRERR
            case BUS_ADRERR: si_code_str = "Non-existent physical address"; break;
#endif
#ifdef BUS_OBJERR
            case BUS_OBJERR: si_code_str = "Objet-specific hardware error"; break;
#endif
            }
            break;
        case SIGTRAP:
            switch (info->si_code)
            {
#ifdef TRAP_BRKPT
            case TRAP_BRKPT: si_code_str = "Process breakpoint"; break;
#endif
#ifdef TRAP_TRACE
            case TRAP_TRACE: si_code_str = "Process trace trap"; break;
#endif
            }
            break;
        case SIGCHLD:
            switch (info->si_code)
            {
#ifdef CLD_EXITED
            case CLD_EXITED: si_code_str = "Child has exited"; break;
#endif
#ifdef CLD_KILLED
            case CLD_KILLED: si_code_str = "Child has terminated abnormally and did not create a core file"; break;
#endif
#ifdef CLD_DUMPED
            case CLD_DUMPED: si_code_str = "Child has terminated abnormally and created a core file"; break;
#endif
#ifdef CLD_WTRAPPED
            case CLD_TRAPPED: si_code_str = "Traced child has trapped"; break;
#endif
#ifdef CLD_STOPPED
            case CLD_STOPPED: si_code_str = "Child has stopped"; break;
#endif
#ifdef CLD_CONTINUED
            case CLD_CONTINUED: si_code_str = "Stopped child has continued"; break;
#endif
            }
            break;
#ifdef SIGPOLL
        case SIGPOLL:
            switch (info->si_code)
            {
#ifdef POLL_IN
            case POLL_IN: si_code_str = "Data input available"; break;
#endif
#ifdef POLL_OUT
            case POLL_OUT: si_code_str = "Output buffers available"; break;
#endif
#ifdef POLL_MSG
            case POLL_MSG: si_code_str = "Input message available"; break;
#endif
#ifdef POLL_ERR
            case POLL_ERR: si_code_str = "I/O error"; break;
#endif
#ifdef POLL_PRI
            case POLL_PRI: si_code_str = "High priority input available"; break;
#endif
#ifdef POLL_HUP
            case POLL_HUP: si_code_str = "Device disconnected"; break;
#endif
            }
            break;
#endif /* SIGPOLL */
        default:
            switch (info->si_code)
            {
#ifdef SI_ASYNCNL
            case SI_ASYNCNL: si_code_str = "SI_ASYNCNL"; break;
#endif
#ifdef SI_SIGIO
            case SI_SIGIO: si_code_str = "Queued SIGIO"; break;
#endif
#ifdef SI_ASYNCIO
            case SI_ASYNCIO: si_code_str = "Asynchronous I/O request completed"; break;
#endif
#ifdef SI_MESGQ
            case SI_MESGQ: si_code_str = "Message queue state changed"; break;
#endif
            case SI_TIMER: si_code_str = "Timer expiration"; break;
            case SI_QUEUE: si_code_str = "Sigqueue() signal"; break;
            case SI_USER: si_code_str = "User function (kill, sigsend, abort, etc.)"; break;
#ifdef SI_KERNEL
            case SI_KERNEL: si_code_str = "Kernel signal"; break;
#endif
#ifdef SI_UNDEFINED
            case SI_UNDEFINED: si_code_str = "Undefined code"; break;
#endif
            }
        }

        /* print signal errno information */
        if (0 != info->si_errno) {
            ret = snprintf(tmp, size, HOSTFORMAT "Associated errno: %s (%d)\n",
                           stacktrace_hostname, getpid(), 
                           strerror (info->si_errno), info->si_errno);
            size -= ret;
            tmp += ret;
        }

        ret = snprintf(tmp, size, HOSTFORMAT "Signal code: %s (%d)\n",
                       stacktrace_hostname, getpid(), 
                       si_code_str, info->si_code);
        size -= ret;
        tmp += ret;

        switch (signo)
        {
        case SIGILL:
        case SIGFPE: 
        case SIGSEGV: 
        case SIGBUS:
        {
            ret = snprintf(tmp, size, HOSTFORMAT "Failing at address: %p\n",
                           stacktrace_hostname, getpid(), info->si_addr);
            size -= ret;
            tmp += ret;
            break;
        }
        case SIGCHLD: 
        {
            ret = snprintf(tmp, size, HOSTFORMAT "Sending PID: %d, Sending UID: %d, Status: %d\n",
                           stacktrace_hostname, getpid(), 
                           info->si_pid, info->si_uid, info->si_status);
            size -= ret;
            tmp += ret;
            break;
        }
#ifdef SIGPOLL
        case SIGPOLL:
        {
#ifdef HAVE_SIGINFO_T_SI_FD
            ret = snprintf(tmp, size, HOSTFORMAT "Band event: %ld, File Descriptor : %d\n",
                           stacktrace_hostname, getpid(), info->si_band, info->si_fd);
#elif HAVE_SIGINFO_T_SI_BAND
            ret = snprintf(tmp, size, HOSTFORMAT "Band event: %ld\n",
                           stacktrace_hostname, getpid(), info->si_band);
#else
            ret = 0;
#endif
            size -= ret;
            tmp += ret;
            break;
        }
#endif
        }
    } else {
        ret = snprintf(tmp, size,
                       HOSTFORMAT "siginfo is NULL, additional information unavailable\n",
                       stacktrace_hostname, getpid());
        size -= ret;
        tmp += ret;
    }

    /* write out the signal information generated above */
    write(fileno(stderr), print_buffer, sizeof(print_buffer)-size);
    fflush(stderr);

    /* print out the stack trace */
    ret = opal_backtrace_buffer(&traces, &traces_size);
    if (OPAL_SUCCESS == ret) {
        int i;
        /* since we have the opportunity, strip off the bottom two
           function calls, which will be this function and
           opa_backtrace_buffer(). */
        for (i = 2 ; i < traces_size ; ++i) {
            ret = snprintf(print_buffer, sizeof(print_buffer),
                           HOSTFORMAT "[%2d] %s\n",
                           stacktrace_hostname, getpid(), i - 2, traces[i]);
            write(fileno(stderr), print_buffer, ret);
        }
    } else {
        opal_backtrace_print(stderr);
    }

    /* write out the footer information */
    memset (print_buffer, 0, sizeof (print_buffer));
    ret = snprintf(print_buffer, sizeof(print_buffer), 
                   HOSTFORMAT "*** End of error message ***\n", 
                   stacktrace_hostname, getpid());
    write(fileno(stderr), print_buffer, ret);
    fflush(stderr);
}

#endif /* OMPI_WANT_PRETTY_PRINT_STACKTRACE && ! defined(__WINDOWS__) */


/**
 * Here we register the opal_show_stackframe function for signals
 * passed to OpenMPI by the mpi_signal-parameter passed to mpirun
 * by the user.
 *
 *  @returnvalue OPAL_SUCCESS
 *  @returnvalue OPAL_ERR_BAD_PARAM if the value in the signal-list
 *    is not a valid signal-number
 *               
 */
int opal_util_register_stackhandlers (void)
{
#if OMPI_WANT_PRETTY_PRINT_STACKTRACE && ! defined(__WINDOWS__)
    struct sigaction act;
    char * string_value;
    char * tmp;
    char * next;
    int param, i;

    gethostname(stacktrace_hostname, sizeof(stacktrace_hostname));
    stacktrace_hostname[sizeof(stacktrace_hostname) - 1] = '\0';
    /* to keep these somewhat readable, only print the machine name */
    for (i = 0 ; i < (int)sizeof(stacktrace_hostname) ; ++i) {
        if (stacktrace_hostname[i] == '.') {
            stacktrace_hostname[i] = '\0';
            break;
        }
    }

    param = mca_base_param_find ("opal", NULL, "signal");
    mca_base_param_lookup_string (param, &string_value);

    memset(&act, 0, sizeof(act));
    act.sa_sigaction = opal_show_stackframe;
    act.sa_flags = SA_SIGINFO;
#ifdef SA_ONESHOT
    act.sa_flags |= SA_ONESHOT;
#else
    act.sa_flags |= SA_RESETHAND;
#endif

    for (tmp = next = string_value ; 
	 next != NULL && *next != '\0'; 
	 tmp = next + 1)
    {
      int sig;
      int ret;

      sig = strtol (tmp, &next, 10);

      /*
       *  If there is no sensible number in the string, exit.
       *  Similarly for any number which is not in the signal-number range
       */
      if (((0 == sig) && (tmp == next)) || (0 > sig) || (_NSIG <= sig)) {
	 return OPAL_ERR_BAD_PARAM;
      }

      if ((next == NULL) || ((*next != ',') && (*next != '\0'))) {
	 return OPAL_ERR_BAD_PARAM;
      }

      ret = sigaction (sig, &act, NULL);
      if (ret != 0) {
        return OPAL_ERR_IN_ERRNO;
      }
    }
    free(string_value);
#endif /* OMPI_WANT_PRETTY_PRINT_STACKTRACE && ! defined(__WINDOWS__) */

    return OPAL_SUCCESS;
}