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/*
* Copyright (C) 1985-1992 New York University
*
* This file is part of the Ada/Ed-C system. See the Ada/Ed README file for
* warranty (none) and distribution info and also the GNU General Public
* License for more details.
*/
/* action.c - temporarily pulled out from adaprs.c */
#include "ada.h"
#include "miscprots.h"
#include "actionprots.h"
/* Action: Return an action corresponding to a given state and input
symbol. Given a state and input symbol, we get a unique value uniquevalue,
which we use to get a hash value hashvalue. We use hashvalue as an index
into act_tab1. If the entry is 0, we return the default action for the
state. If the table entry is < NUM_ACTIONS, then we return either
the table entry if act_tab2 gives uniquenum at location hashvalue, or
the default reduction if not. Otherwise we go through act_tab2 starting
at index uniquevalue until we find uniquevalue or 0, and return what
is found in act_tab1 at this location or the default reduction,
respectively. A shift is indicated by the new state to go to after the
shift, and a reduction is indicated by the rule number + NUM_STATES. */
int action(int state, int sym) /*;action*/
{
long uniquenum;
int hashvalue;
int i;
int aval;
#ifdef DEBUGACT
printf("action state %d sym %d\n", state, sym); /*DEBUG*/
#endif
if (state < 0) {
#ifdef DEBUG
printf("action: fatal error state negative %d\n", state);
#endif
exitp(RC_INTERNAL_ERROR);
}
if (sym < 0) {
#ifdef DEBUG
printf("action: fatal error sym negative %d\n", sym);
#endif
exitp(RC_INTERNAL_ERROR);
}
#ifdef DEBUGACT
uniquenum = state;
printf("uniq = state %ld\n", uniquenum);
uniquenum *= NUM_INPUTS;
printf("uniq = NUM_INT %ld\n", uniquenum);
uniquenum += sym;
printf("uniq += sym %ld\n", uniquenum);
hashvalue = uniquenum % TABLE_SIZE;
printf("action hash long %ld becomes %d\n", uniquenum, hashvalue);
aval = act_tab1[hashvalue];
printf("initial act_tab1 value for %d is %d\n", hashvalue, aval);
if (act_tab1[hashvalue] == 0) {
aval = def_action[state - 1];
printf("action 1st case %d\n", aval);
return(aval);
}
if (act_tab1[hashvalue] < NUM_ACTIONS) {
if (act_tab2[hashvalue]== uniquenum) {
aval = act_tab1[hashvalue];
printf("action 2nd case %d\n", aval);
return aval;
}
else {
aval = def_action[state-1];
printf("acton 3rd case %d\n", aval);
return aval;
}
}
for (i = act_tab1[hashvalue] - NUM_ACTIONS; act_tab2[i] != 0; i++) {
if (act_tab2[i] == uniquenum) {
aval = act_tab1[i];
printf("action 4th case %d %d\n", i, aval);
return aval;
}
}
aval = def_action[state-1];
printf("action 5th case %d\n", aval);
return(aval);
#else
uniquenum = (long) state * NUM_INPUTS + sym;
hashvalue = (int)uniquenum % TABLE_SIZE;
aval = act_tab1[hashvalue];
if (aval == 0)
return(def_action[state - 1]);
if (aval < NUM_ACTIONS)
return((act_tab2[hashvalue] == uniquenum) ? aval : def_action[state-1]);
for (i = act_tab1[hashvalue] - NUM_ACTIONS; act_tab2[i] != 0; i++)
if (act_tab2[i] == uniquenum)
return(act_tab1[i]);
return(def_action[state - 1]);
#endif
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.