/* * fgrep -- print all lines containing any of a set of keywords * *	status returns: *		0 - ok, and some matches *		1 - ok, but no matches *		2 - some error */#include <stdio.h>#define	MAXSIZ 6000#define QSIZE 400struct words {	char 	inp;	char	out;	struct	words *nst;	struct	words *link;	struct	words *fail;} w[MAXSIZ], *smax, *q;long	lnum;int	bflag, cflag, fflag, lflag, nflag, vflag, xflag;int	hflag	= 1;int	sflag;int	nfile;long	blkno;int	nsucc;long	tln;FILE	*wordf;char	*argptr;main(argc, argv)char **argv;{	while (--argc > 0 && (++argv)[0][0]=='-')		switch (argv[0][1]) {		case 's':			sflag++;			continue;		case 'h':			hflag = 0;			continue;		case 'b':			bflag++;			continue;		case 'c':			cflag++;			continue;		case 'e':			argc--;			argv++;			goto out;		case 'f':			fflag++;			continue;		case 'l':			lflag++;			continue;		case 'n':			nflag++;			continue;		case 'v':			vflag++;			continue;		case 'x':			xflag++;			continue;		default:			fprintf(stderr, "egrep: unknown flag\n");			continue;		}out:	if (argc<=0)		exit(2);	if (fflag) {		wordf = fopen(*argv, "r");		if (wordf==NULL) {			fprintf(stderr, "egrep: can't open %s\n", *argv);			exit(2);		}	}	else argptr = *argv;	argc--;	argv++;	cgotofn();	cfail();	nfile = argc;	if (argc<=0) {		if (lflag) exit(1);		execute((char *)NULL);	}	else while (--argc >= 0) {		execute(*argv);		argv++;	}	exit(nsucc == 0);}execute(file)char *file;{	register char *p;	register struct words *c;	register ccount;	char buf[1024];	int f;	int failed;	char *nlp;	if (file) {		if ((f = open(file, 0)) < 0) {			fprintf(stderr, "fgrep: can't open %s\n", file);			exit(2);		}	}	else f = 0;	ccount = 0;	failed = 0;	lnum = 1;	tln = 0;	blkno = 0;	p = buf;	nlp = p;	c = w;	for (;;) {		if (--ccount <= 0) {			if (p == &buf[1024]) p = buf;			if (p > &buf[512]) {				if ((ccount = read(f, p, &buf[1024] - p)) <= 0) break;			}			else if ((ccount = read(f, p, 512)) <= 0) break;			blkno += ccount;		}		nstate:			if (c->inp == *p) {				c = c->nst;			}			else if (c->link != 0) {				c = c->link;				goto nstate;			}			else {				c = c->fail;				failed = 1;				if (c==0) {					c = w;					istate:					if (c->inp == *p) {						c = c->nst;					}					else if (c->link != 0) {						c = c->link;						goto istate;					}				}				else goto nstate;			}		if (c->out) {			while (*p++ != '\n') {				if (--ccount <= 0) {					if (p == &buf[1024]) p = buf;					if (p > &buf[512]) {						if ((ccount = read(f, p, &buf[1024] - p)) <= 0) break;					}					else if ((ccount = read(f, p, 512)) <= 0) break;					blkno += ccount;				}			}			if ( (vflag && (failed == 0 || xflag == 0)) || (vflag == 0 && xflag && failed) )				goto nomatch;	succeed:	nsucc = 1;			if (cflag) tln++;			else if (sflag)				;	/* ugh */			else if (lflag) {				printf("%s\n", file);				close(f);				return;			}			else {				if (nfile > 1 && hflag) printf("%s:", file);				if (bflag) printf("%ld:", (blkno-ccount-1)/512);				if (nflag) printf("%ld:", lnum);				if (p <= nlp) {					while (nlp < &buf[1024]) putchar(*nlp++);					nlp = buf;				}				while (nlp < p) putchar(*nlp++);			}	nomatch:	lnum++;			nlp = p;			c = w;			failed = 0;			continue;		}		if (*p++ == '\n')			if (vflag) goto succeed;			else {				lnum++;				nlp = p;				c = w;				failed = 0;			}	}	close(f);	if (cflag) {		if (nfile > 1)			printf("%s:", file);		printf("%ld\n", tln);	}}getargc(){	register c;	if (wordf)		return(getc(wordf));	if ((c = *argptr++) == '\0')		return(EOF);	return(c);}cgotofn() {	register c;	register struct words *s;	s = smax = w;nword:	for(;;) {		c = getargc();		if (c==EOF)			return;		if (c == '\n') {			if (xflag) {				for(;;) {					if (s->inp == c) {						s = s->nst;						break;					}					if (s->inp == 0) goto nenter;					if (s->link == 0) {						if (smax >= &w[MAXSIZ -1]) overflo();						s->link = ++smax;						s = smax;						goto nenter;					}					s = s->link;				}			}			s->out = 1;			s = w;		} else {		loop:	if (s->inp == c) {				s = s->nst;				continue;			}			if (s->inp == 0) goto enter;			if (s->link == 0) {				if (smax >= &w[MAXSIZ - 1]) overflo();				s->link = ++smax;				s = smax;				goto enter;			}			s = s->link;			goto loop;		}	}	enter:	do {		s->inp = c;		if (smax >= &w[MAXSIZ - 1]) overflo();		s->nst = ++smax;		s = smax;	} while ((c = getargc()) != '\n' && c!=EOF);	if (xflag) {	nenter:	s->inp = '\n';		if (smax >= &w[MAXSIZ -1]) overflo();		s->nst = ++smax;	}	smax->out = 1;	s = w;	if (c != EOF)		goto nword;}overflo() {	fprintf(stderr, "wordlist too large\n");	exit(2);}cfail() {	struct words *queue[QSIZE];	struct words **front, **rear;	struct words *state;	register char c;	register struct words *s;	s = w;	front = rear = queue;init:	if ((s->inp) != 0) {		*rear++ = s->nst;		if (rear >= &queue[QSIZE - 1]) overflo();	}	if ((s = s->link) != 0) {		goto init;	}	while (rear!=front) {		s = *front;		if (front == &queue[QSIZE-1])			front = queue;		else front++;	cloop:	if ((c = s->inp) != 0) {			*rear = (q = s->nst);			if (front < rear)				if (rear >= &queue[QSIZE-1])					if (front == queue) overflo();					else rear = queue;				else rear++;			else				if (++rear == front) overflo();			state = s->fail;		floop:	if (state == 0) state = w;			if (state->inp == c) {				q->fail = state->nst;				if ((state->nst)->out == 1) q->out = 1;				continue;			}			else if ((state = state->link) != 0)				goto floop;		}		if ((s = s->link) != 0)			goto cloop;	}}