void
vfail(const char *format, va_list alist)
{
extern const char *volatile _mdb_abort_str;
static char buf[256];
static int nfail;
if (_mdb_abort_str == NULL) {
_mdb_abort_str = buf; /* Do this first so we don't recurse */
(void) mdb_iob_vsnprintf(buf, sizeof (buf), format, alist);
nfail = 1;
}
/*
* We'll try to print failure messages twice. Any more than that,
* and we're probably hitting an assertion or some other problem in
* the printing routines, and will recurse until we run out of stack.
*/
if (nfail++ < 3) {
mdb_iob_printf(mdb.m_err, "%s ABORT: ", mdb.m_pname);
mdb_iob_vprintf(mdb.m_err, format, alist);
mdb_iob_flush(mdb.m_err);
(void) mdb_signal_blockall();
(void) mdb_signal_raise(SIGABRT);
(void) mdb_signal_unblock(SIGABRT);
}
exit(1);
}
/*ARGSUSED*/
static void
flt_handler(int sig, siginfo_t *sip, ucontext_t *ucp, void *data)
{
static const struct rlimit rl = {
(rlim_t)RLIM_INFINITY, (rlim_t)RLIM_INFINITY
};
const mdb_idcmd_t *idcp = NULL;
if (mdb.m_frame != NULL && mdb.m_frame->f_cp != NULL)
idcp = mdb.m_frame->f_cp->c_dcmd;
if (sip != NULL)
bcopy(sip, &_mdb_abort_info, sizeof (_mdb_abort_info));
if (ucp != NULL)
bcopy(ucp, &_mdb_abort_ctx, sizeof (_mdb_abort_ctx));
_mdb_abort_info.si_signo = sig;
(void) mdb_signal_sethandler(sig, SIG_DFL, NULL);
/*
* If there is no current dcmd, or the current dcmd comes from a
* builtin module, we don't allow resume and always core dump.
*/
if (idcp == NULL || idcp->idc_modp == NULL ||
idcp->idc_modp == &mdb.m_rmod || idcp->idc_modp->mod_hdl == NULL)
goto dump;
if (mdb.m_term != NULL) {
struct frame *fr = (struct frame *)
(ucp->uc_mcontext.gregs[STACK_REGISTER] + STACK_BIAS);
char signame[SIG2STR_MAX];
int i = 1;
char c;
if (sig2str(sig, signame) == -1) {
mdb_iob_printf(mdb.m_err,
"\n*** %s: received signal %d at:\n",
mdb.m_pname, sig);
} else {
mdb_iob_printf(mdb.m_err,
"\n*** %s: received signal %s at:\n",
mdb.m_pname, signame);
}
if (ucp->uc_mcontext.gregs[REG_PC] != 0)
print_frame(ucp->uc_mcontext.gregs[REG_PC], i++);
while (fr != NULL && valid_frame(fr) && fr->fr_savpc != 0) {
print_frame(fr->fr_savpc, i++);
fr = (struct frame *)
((uintptr_t)fr->fr_savfp + STACK_BIAS);
}
query:
mdb_iob_printf(mdb.m_err, "\n%s: (c)ore dump, (q)uit, "
"(r)ecover, or (s)top for debugger [cqrs]? ", mdb.m_pname);
mdb_iob_flush(mdb.m_err);
for (;;) {
if (IOP_READ(mdb.m_term, &c, sizeof (c)) != sizeof (c))
goto dump;
switch (c) {
case 'c':
case 'C':
(void) setrlimit(RLIMIT_CORE, &rl);
mdb_iob_printf(mdb.m_err, "\n%s: attempting "
"to dump core ...\n", mdb.m_pname);
goto dump;
case 'q':
case 'Q':
mdb_iob_discard(mdb.m_out);
mdb_iob_nl(mdb.m_err);
(void) mdb_signal_unblockall();
terminate(1);
/*NOTREACHED*/
case 'r':
case 'R':
mdb_iob_printf(mdb.m_err, "\n%s: unloading "
"module '%s' ...\n", mdb.m_pname,
idcp->idc_modp->mod_name);
(void) mdb_module_unload(
idcp->idc_modp->mod_name, 0);
(void) mdb_signal_sethandler(sig,
flt_handler, NULL);
_mdb_abort_rcount++;
mdb.m_intr = 0;
mdb.m_pend = 0;
(void) mdb_signal_unblockall();
longjmp(mdb.m_frame->f_pcb, MDB_ERR_ABORT);
/*NOTREACHED*/
case 's':
case 'S':
mdb_iob_printf(mdb.m_err, "\n%s: "
"attempting to stop pid %d ...\n",
mdb.m_pname, (int)getpid());
/*
* Stop ourself; if this fails or we are
* subsequently continued, ask again.
*/
(void) mdb_signal_raise(SIGSTOP);
(void) mdb_signal_unblockall();
goto query;
}
}
}
dump:
if (SI_FROMUSER(sip)) {
(void) mdb_signal_block(sig);
(void) mdb_signal_raise(sig);
}
(void) sigfillset(&ucp->uc_sigmask);
(void) sigdelset(&ucp->uc_sigmask, sig);
if (_mdb_abort_str == NULL)
_mdb_abort_str = "fatal signal received";
ucp->uc_flags |= UC_SIGMASK;
(void) setcontext(ucp);
}
