/* Copyright (c) 1985 Ceriel J.H. Jacobs */# ifndef lintstatic char rcsid[] = "$Header: machine.c,v 7.1 87/01/09 11:09:58 ceriel Exp $";# endif# define _MACHINE_# include <ctype.h># include "in_all.h"# include "machine.h"# include "getline.h"# include "assert.h"/* * Add part of finite state machine to recognize the string s. */STATIC intaddtomach(s, cnt, list) char *s; struct state **list; {	register struct state *l;	register int i = FSM_OKE;	/* Return value */	register int j;	for (;;) {		l = *list;		if (!l) {			/*			 * Create new list element			 */			*list = l = (struct state *) alloc(sizeof(*l), 0);			l->s_char = *s;			l->s_endstate = 0;			l->s_match = 0;			l->s_next = 0;		}		if (l->s_char == *s) {			/*			 * Continue with next character			 */			if (!*++s) {				/*				 * No next character				 */				j = l->s_endstate;				l->s_endstate = 1;				if (l->s_match || j) {					/*					 * If the state already was an endstate,					 * or has a successor, the currently					 * added string is a prefix of an					 * already recognized string					 */					return FSM_ISPREFIX;				}				l->s_cnt = cnt;				return i;			}			if (l->s_endstate) {				/*				 * In this case, the currently added string has				 * a prefix that is an already recognized				 * string.				 */				i = FSM_HASPREFIX;			}			list = &(l->s_match);			continue;		}		list = &(l->s_next);	}	/* NOTREACHED */}/* * Add a string to the FSM. */intaddstring(s,cnt,machine) register char *s; struct state **machine; {	if (!s || !*s) {		return FSM_ISPREFIX;	}	return addtomach(s,cnt,machine);}/* * Match string s with the finite state machine. * If it matches, the number of characters actually matched is returned, * and the count is put in the word pointed to by i. * If the string is a prefix of a string that could be matched, * FSM_ISPREFIX is returned. Otherwise, 0 is returned. */intmatch(s,i,mach) char *s; int *i; register struct state *mach; {	register char *s1 = s;	/* Walk through string */	register struct state *mach1 = 0;				/* Keep track of previous state */	while (mach && *s1) {		if (mach->s_char == *s1) {			/*			 * Current character matches. Carry on with next			 * character and next state			 */			mach1 = mach;			mach = mach->s_match;			s1++;			continue;		}		mach = mach->s_next;	}	if (!mach1) {		/*		 * No characters matched		 */		return 0;	}	if (mach1->s_endstate) {		/*		 * The string matched		 */		*i = mach1->s_cnt;		return s1 - s;	}	if (!*s1) {		/*		 * The string matched a prefix		 */		return FSM_ISPREFIX;	}	return 0;}