/* We ignore errors in the $ZYERROR routine. When an error occurs, we unwind all stack frames upto and including
* zyerr_frame. MUM_TSTART then transfers control to the $ZTRAP frame.
*/
boolean_t clean_mum_tstart(void)
{
stack_frame *save_zyerr_frame, *fp, *fpprev;
boolean_t save_check_flag;
if (NULL != zyerr_frame)
{
while ((NULL != frame_pointer) && (NULL != zyerr_frame))
{
GOFRAMES(1, TRUE, FALSE);
}
assert(NULL != frame_pointer);
proc_act_type = 0;
if (indr_stringpool.base == stringpool.base)
{ /* switch to run time stringpool */
indr_stringpool = stringpool;
stringpool = rts_stringpool;
}
return TRUE;
}
return (NULL != err_act);
}
int gtm_trigger(gv_trigger_t *trigdsc, gtm_trigger_parms *trigprm)
{
mval *lvvalue;
lnr_tabent *lbl_offset_p;
uchar_ptr_t transfer_addr;
lv_val *lvval;
mname_entry *mne_p;
uint4 *indx_p;
ht_ent_mname *tabent;
boolean_t added;
int clrlen, rc, i, unwinds;
mval **lvvalarray;
mv_stent *mv_st_ent;
symval *new_symval;
uint4 dollar_tlevel_start;
stack_frame *fp, *fpprev;
DCL_THREADGBL_ACCESS;
SETUP_THREADGBL_ACCESS;
assert(!skip_dbtriggers); /* should not come here if triggers are not supposed to be invoked */
assert(trigdsc);
assert(trigprm);
assert((NULL != trigdsc->rtn_desc.rt_adr) || ((MV_STR & trigdsc->xecute_str.mvtype)
&& (0 != trigdsc->xecute_str.str.len)
&& (NULL != trigdsc->xecute_str.str.addr)));
assert(dollar_tlevel);
/* Determine if trigger needs to be compiled */
if (NULL == trigdsc->rtn_desc.rt_adr)
{ /* No routine hdr addr exists. Need to do compile */
if (0 != gtm_trigger_complink(trigdsc, TRUE))
{
PRN_ERROR; /* Leave record of what error caused the compilation failure if any */
rts_error(VARLSTCNT(4) ERR_TRIGCOMPFAIL, 2, trigdsc->rtn_desc.rt_name.len, trigdsc->rtn_desc.rt_name.addr);
}
}
assert(trigdsc->rtn_desc.rt_adr);
assert(trigdsc->rtn_desc.rt_adr == CURRENT_RHEAD_ADR(trigdsc->rtn_desc.rt_adr));
/* Setup trigger environment stack frame(s) for execution */
if (!(frame_pointer->type & SFT_TRIGR))
{ /* Create new trigger base frame first that back-stops stack unrolling and return to us */
if (GTM_TRIGGER_DEPTH_MAX < (gtm_trigger_depth + 1)) /* Verify we won't nest too deep */
rts_error(VARLSTCNT(3) ERR_MAXTRIGNEST, 1, GTM_TRIGGER_DEPTH_MAX);
DBGTRIGR((stderr, "gtm_trigger: PUSH: frame_pointer 0x%016lx ctxt value: 0x%016lx\n", frame_pointer, ctxt));
/* Protect against interrupts while we have only a trigger base frame on the stack */
DEFER_INTERRUPTS(INTRPT_IN_TRIGGER_NOMANS_LAND);
/* The current frame invoked a trigger. We cannot return to it for a TP restart or other reason unless
* either the total operation (including trigger) succeeds and we unwind normally or unless the mpc is reset
* (like what happens in various error or restart conditions) because right now it returns to where a database
* command (KILL, SET or ZTRIGGER) was entered. Set flag in the frame to prevent MUM_TSTART unless the frame gets
* reset.
*/
frame_pointer->flags |= SFF_TRIGR_CALLD; /* Do not return to this frame via MUM_TSTART */
DBGTRIGR((stderr, "gtm_trigger: Setting SFF_TRIGR_CALLD in frame 0x"lvaddr"\n", frame_pointer));
base_frame(trigdsc->rtn_desc.rt_adr);
/* Finish base frame initialization - reset mpc/context to return to us without unwinding base frame */
frame_pointer->type |= SFT_TRIGR;
# if defined(__hpux) && defined(__hppa)
/* For HPUX-HPPA (PA-RISC), we use longjmp() to return to gtm_trigger() to avoid some some space register
* corruption issues. Use call-ins already existing mechanism for doing this. Although we no longer support
* HPUX-HPPA for triggers due to some unlocated space register error, this code (effectively always ifdef'd
* out) left in in case it gets resurrected in the future (01/2010 SE).
*/
frame_pointer->mpc = CODE_ADDRESS(ci_ret_code);
frame_pointer->ctxt = GTM_CONTEXT(ci_ret_code);
# else
frame_pointer->mpc = CODE_ADDRESS(gtm_levl_ret_code);
frame_pointer->ctxt = GTM_CONTEXT(gtm_levl_ret_code);
# endif
/* This base stack frame is also where we save environmental info for all triggers invoked at this stack level.
* Subsequent triggers fired at this level in this trigger invocation need only reinitialize a few things but
* can avoid "the big save".
*/
if (NULL == trigr_symval_list)
{ /* No available symvals for use with this trigger, create one */
symbinit(); /* Initialize a symbol table the trigger will use */
curr_symval->trigr_symval = TRUE; /* Mark as trigger symval so will be saved not decommissioned */
} else
{ /* Trigger symval is available for reuse */
new_symval = trigr_symval_list;
assert(new_symval->trigr_symval);
trigr_symval_list = new_symval->last_tab; /* dequeue new curr_symval from list */
REINIT_SYMVAL_BLK(new_symval, curr_symval);
curr_symval = new_symval;
PUSH_MV_STENT(MVST_STAB);
mv_chain->mv_st_cont.mvs_stab = new_symval; /* So unw_mv_ent() can requeue it for later use */
}
/* Push our trigger environment save mv_stent onto the chain */
PUSH_MV_STENT(MVST_TRIGR);
mv_st_ent = mv_chain;
/* Initialize the mv_stent elements processed by stp_gcol which can be called by either op_gvsavtarg() or
* by the extnam saving code below. This initialization keeps stp_gcol - should it be called - from attempting
* to process unset fields filled with garbage in them as valid mstr address/length pairs.
*/
mv_st_ent->mv_st_cont.mvs_trigr.savtarg.str.len = 0;
mv_st_ent->mv_st_cont.mvs_trigr.savextref.len = 0;
mv_st_ent->mv_st_cont.mvs_trigr.dollar_etrap_save.str.len = 0;
mv_st_ent->mv_st_cont.mvs_trigr.dollar_ztrap_save.str.len = 0;
mv_st_ent->mv_st_cont.mvs_trigr.saved_dollar_truth = dollar_truth;
op_gvsavtarg(&mv_st_ent->mv_st_cont.mvs_trigr.savtarg);
if (extnam_str.len)
{
ENSURE_STP_FREE_SPACE(extnam_str.len);
mv_st_ent->mv_st_cont.mvs_trigr.savextref.addr = (char *)stringpool.free;
memcpy(mv_st_ent->mv_st_cont.mvs_trigr.savextref.addr, extnam_str.addr, extnam_str.len);
stringpool.free += extnam_str.len;
assert(stringpool.free <= stringpool.top);
}
mv_st_ent->mv_st_cont.mvs_trigr.savextref.len = extnam_str.len;
mv_st_ent->mv_st_cont.mvs_trigr.ztname_save = dollar_ztname;
mv_st_ent->mv_st_cont.mvs_trigr.ztdata_save = dollar_ztdata;
mv_st_ent->mv_st_cont.mvs_trigr.ztoldval_save = dollar_ztoldval;
mv_st_ent->mv_st_cont.mvs_trigr.ztriggerop_save = dollar_ztriggerop;
mv_st_ent->mv_st_cont.mvs_trigr.ztupdate_save = dollar_ztupdate;
mv_st_ent->mv_st_cont.mvs_trigr.ztvalue_save = dollar_ztvalue;
mv_st_ent->mv_st_cont.mvs_trigr.ztvalue_changed_ptr = ztvalue_changed_ptr;
# ifdef DEBUG
/* In a debug process, these fields give clues of what trigger we are working on */
mv_st_ent->mv_st_cont.mvs_trigr.gtm_trigdsc_last_save = trigdsc;
mv_st_ent->mv_st_cont.mvs_trigr.gtm_trigprm_last_save = trigprm;
# endif
assert(((0 == gtm_trigger_depth) && (ch_at_trigger_init == ctxt->ch))
|| ((0 < gtm_trigger_depth) && (&mdb_condition_handler == ctxt->ch)));
mv_st_ent->mv_st_cont.mvs_trigr.ctxt_save = ctxt;
mv_st_ent->mv_st_cont.mvs_trigr.gtm_trigger_depth_save = gtm_trigger_depth;
if (0 == gtm_trigger_depth)
{ /* Only back up $*trap settings when initiating the first trigger level */
mv_st_ent->mv_st_cont.mvs_trigr.dollar_etrap_save = dollar_etrap;
mv_st_ent->mv_st_cont.mvs_trigr.dollar_ztrap_save = dollar_ztrap;
mv_st_ent->mv_st_cont.mvs_trigr.ztrap_explicit_null_save = ztrap_explicit_null;
dollar_ztrap.str.len = 0;
ztrap_explicit_null = FALSE;
if (NULL != gtm_trigger_etrap.str.addr)
/* An etrap was defined for the trigger environment - Else existing $etrap persists */
dollar_etrap = gtm_trigger_etrap;
}
mv_st_ent->mv_st_cont.mvs_trigr.mumps_status_save = mumps_status;
mv_st_ent->mv_st_cont.mvs_trigr.run_time_save = run_time;
/* See if a MERGE launched the trigger. If yes, save some state so ZWRITE, ZSHOW and/or MERGE can be
* run in the trigger we dispatch. */
if ((0 != merge_args) || TREF(in_zwrite))
PUSH_MVST_MRGZWRSV;
mumps_status = 0;
run_time = TRUE; /* Previous value saved just above restored when frame pops */
} else
{ /* Trigger base frame exists so reinitialize the symbol table for new trigger invocation */
REINIT_SYMVAL_BLK(curr_symval, curr_symval->last_tab);
/* Locate the MVST_TRIGR mv_stent containing the backed up values. Some of those values need
* to be restored so the 2nd trigger has the same environment as the previous trigger at this level
*/
for (mv_st_ent = mv_chain;
(NULL != mv_st_ent) && (MVST_TRIGR != mv_st_ent->mv_st_type);
mv_st_ent = (mv_stent *)(mv_st_ent->mv_st_next + (char *)mv_st_ent))
;
assert(NULL != mv_st_ent);
assert((char *)mv_st_ent < (char *)frame_pointer); /* Ensure mv_stent associated this trigger frame */
/* Reinit backed up values from the trigger environment backup */
dollar_truth = mv_st_ent->mv_st_cont.mvs_trigr.saved_dollar_truth;
op_gvrectarg(&mv_st_ent->mv_st_cont.mvs_trigr.savtarg);
extnam_str.len = mv_st_ent->mv_st_cont.mvs_trigr.savextref.len;
if (extnam_str.len)
memcpy(extnam_str.addr, mv_st_ent->mv_st_cont.mvs_trigr.savextref.addr, extnam_str.len);
mumps_status = 0;
assert(run_time);
/* Note we do not reset the handlers for parallel triggers - set one time only when enter first level
* trigger. After that, whatever happens in trigger world, stays in trigger world.
*/
}
assert(frame_pointer->type & SFT_TRIGR);
# ifdef DEBUG
gtm_trigdsc_last = trigdsc;
gtm_trigprm_last = trigprm;
# endif
/* Set new value of trigger ISVs. Previous values already saved in trigger base frame */
dollar_ztname = &trigdsc->rtn_desc.rt_name;
dollar_ztdata = (mval *)trigprm->ztdata_new;
dollar_ztoldval = trigprm->ztoldval_new;
dollar_ztriggerop = (mval *)trigprm->ztriggerop_new;
dollar_ztupdate = trigprm->ztupdate_new;
dollar_ztvalue = trigprm->ztvalue_new;
ztvalue_changed_ptr = &trigprm->ztvalue_changed;
/* Set values associated with trigger into symbol table */
lvvalarray = trigprm->lvvalarray;
for (i = 0, mne_p = trigdsc->lvnamearray, indx_p = trigdsc->lvindexarray;
i < trigdsc->numlvsubs; ++i, ++mne_p, ++indx_p)
{ /* Once thru for each subscript we are to set */
lvvalue = lvvalarray[*indx_p]; /* Locate mval that contains value */
assert(NULL != lvvalue);
assert(MV_DEFINED(lvvalue)); /* No sense in defining the undefined */
lvval = lv_getslot(curr_symval); /* Allocate an lvval to put into symbol table */
LVVAL_INIT(lvval, curr_symval);
lvval->v = *lvvalue; /* Copy mval into lvval */
added = add_hashtab_mname_symval(&curr_symval->h_symtab, mne_p, lvval, &tabent);
assert(added);
assert(NULL != tabent);
}
/* While the routine header is available in trigdsc, we also need the <null> label address associated with
* the first (and only) line of code.
*/
lbl_offset_p = LNRTAB_ADR(trigdsc->rtn_desc.rt_adr);
transfer_addr = (uchar_ptr_t)LINE_NUMBER_ADDR(trigdsc->rtn_desc.rt_adr, lbl_offset_p);
/* Create new stack frame for invoked trigger in same fashion as gtm_init_env() creates its 2ndary frame */
# ifdef HAS_LITERAL_SECT
new_stack_frame(trigdsc->rtn_desc.rt_adr, (unsigned char *)LINKAGE_ADR(trigdsc->rtn_desc.rt_adr), transfer_addr);
# else
/* Any platform that does not follow pv-based linkage model either
* (1) uses the following calculation to determine the context pointer value, or
* (2) doesn't need a context pointer
*/
new_stack_frame(trigdsc->rtn_desc.rt_adr, PTEXT_ADR(trigdsc->rtn_desc.rt_adr), transfer_addr);
# endif
dollar_tlevel_start = dollar_tlevel;
assert(gv_target->gd_csa == cs_addrs);
gv_target->trig_local_tn = local_tn; /* Record trigger being driven for this global */
/* Invoke trigger generated code */
rc = gtm_trigger_invoke();
if (1 == rc)
{ /* Normal return code (from dm_start). Check if TP has been unwound or not */
assert(dollar_tlevel <= dollar_tlevel_start); /* Bigger would be quite the surprise */
if (dollar_tlevel < dollar_tlevel_start)
{ /* Our TP level was unwound during the trigger so throw an error */
DBGTRIGR((stderr, "gtm_trigger: $TLEVEL less than at start - throwing TRIGTLVLCHNG\n"));
gtm_trigger_fini(TRUE, FALSE); /* dump this trigger level */
rts_error(VARLSTCNT(4) ERR_TRIGTLVLCHNG, 2, trigdsc->rtn_desc.rt_name.len,
trigdsc->rtn_desc.rt_name.addr);
}
rc = 0; /* Be polite and return 0 for the (hopefully common) success case */
} else if (ERR_TPRETRY == rc)
{ /* We are restarting the entire transaction. There are two possibilities here:
* 1) This is a nested trigger level in which case we need to unwind further or
* the outer trigger level was created by M code. If either is true, just
* rethrow the TPRETRY error.
* 2) This is the outer trigger and the call to op_tstart() was done by our caller.
* In this case, we just return to our caller with a code signifying they need
* to restart the implied transaction.
*/
assert(dollar_tlevel && (tstart_trigger_depth <= gtm_trigger_depth));
if ((tstart_trigger_depth < gtm_trigger_depth) || !tp_pointer->implicit_tstart || !tp_pointer->implicit_trigger)
{ /* Unwind a trigger level to restart level or to next trigger boundary */
gtm_trigger_fini(FALSE, FALSE); /* Get rid of this trigger level - we won't be returning */
DBGTRIGR((stderr, "gtm_trigger: dm_start returned rethrow code - rethrowing ERR_TPRETRY\n"));
INVOKE_RESTART;
} else
{ /* It is possible we are restarting a transaction that never got around to creating a base
* frame yet the implicit TStart was done. So if there is no trigger base frame, do not
* run gtm_trigger_fini() but instead do the one piece of cleanup it does that we still need.
*/
assert(donot_INVOKE_MUMTSTART);
if (SFT_TRIGR & frame_pointer->type)
{ /* Normal case when TP restart unwinding back to implicit beginning */
gtm_trigger_fini(FALSE, FALSE);
DBGTRIGR((stderr, "gtm_trigger: dm_start returned rethrow code - returning to gvcst_<caller>\n"));
} else
{ /* Unusual case of trigger that died in no-mans-land before trigger base frame established.
* Remove the "do not return to me" flag only on non-error unwinds */
assert(tp_pointer->implicit_tstart);
assert(SFF_TRIGR_CALLD & frame_pointer->flags);
frame_pointer->flags &= SFF_TRIGR_CALLD_OFF;
DBGTRIGR((stderr, "gtm_trigger: turning off SFF_TRIGR_CALLD (1) in frame 0x"lvaddr"\n",
frame_pointer));
DBGTRIGR((stderr, "gtm_trigger: unwinding no-base-frame trigger for TP restart\n"));
}
}
/* Fall out and return ERR_TPRETRY to caller */
} else if (0 == rc)
/* We should never get a return code of 0. This would be out-of-design and a signal that something
* is quite broken. We cannot "rethrow" outside the trigger because it was not initially an error so
* mdb_condition_handler would have no record of it (rethrown errors must have originally occurred in
* or to be RE-thrown) and assert fail at best.
*/
GTMASSERT;
else
{ /* We have an unexpected return code due to some error during execution of the trigger that tripped
* gtm_trigger's safety handler (i.e. an error occurred in mdb_condition_handler() established by
* dm_start(). Since we are going to unwind the trigger frame and rethrow the error, we also have
* to unwind all the stack frames on top of the trigger frame. Figure out how many frames that is,
* unwind them all plus the trigger base frame before rethrowing the error.
*/
for (unwinds = 0, fp = frame_pointer; (NULL != fp) && !(SFT_TRIGR & fp->type); fp = fp->old_frame_pointer)
unwinds++;
assert((NULL != fp) && (SFT_TRIGR & fp->type));
GOFRAMES(unwinds, TRUE, FALSE);
assert((NULL != frame_pointer) && !(SFT_TRIGR & frame_pointer->type));
DBGTRIGR((stderr, "gtm_trigger: Unsupported return code (%d) - unwound %d frames and now rethrowing error\n",
rc, unwinds));
rts_error(VARLSTCNT(1) ERR_REPEATERROR);
}
return rc;
}