Return to main.c CVS log

Up to [local] / src / usr.bin / m4

cgd: add a typedef which describes elements in the push-back buffer.  Make
that typedef 'short'.  'char' (which was previously used) because char
may be unsigned and ((char)EOF) != EOF if that is the case.  That was
causing the (char)EOF (0xff) pushed back in main to be interepreted as
a character, and, in some cases, to be written to the output.  'short'
was used rather than 'signed char' because if the latter is used,
0xff characters in the input would confuse m4.  (No point in introducing
(more?) 8-bit lossage.)

/*	$OpenBSD: main.c,v 1.6 1997/12/10 20:24:15 deraadt Exp $	*/
/*	$NetBSD: main.c,v 1.11 1996/01/13 23:25:26 pk Exp $	*/

/*-
 * Copyright (c) 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ozan Yigit at York University.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1989, 1993\n\
	The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)main.c	8.1 (Berkeley) 6/6/93";
#else
static char rcsid[] = "$OpenBSD: main.c,v 1.6 1997/12/10 20:24:15 deraadt Exp $";
#endif
#endif /* not lint */

/*
 * main.c
 * Facility: m4 macro processor
 * by: oz
 */

#include <sys/types.h>
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include "mdef.h"
#include "stdd.h"
#include "extern.h"
#include "pathnames.h"

ndptr hashtab[HASHSIZE];	/* hash table for macros etc.  */
pbent buf[BUFSIZE];		/* push-back buffer	       */
pbent *bufbase = buf;		/* the base for current ilevel */
pbent *bbase[MAXINP];		/* the base for each ilevel    */
pbent *bp = buf; 		/* first available character   */
pbent *endpbb = buf+BUFSIZE;	/* end of push-back buffer     */
stae mstack[STACKMAX+1]; 	/* stack of m4 machine         */
char strspace[STRSPMAX+1];	/* string space for evaluation */
char *ep = strspace;		/* first free char in strspace */
char *endest= strspace+STRSPMAX;/* end of string space	       */
int sp; 			/* current m4  stack pointer   */
int fp; 			/* m4 call frame pointer       */
FILE *infile[MAXINP];		/* input file stack (0=stdin)  */
FILE *outfile[MAXOUT];		/* diversion array(0=bitbucket)*/
FILE *active;			/* active output file pointer  */
char *m4temp;			/* filename for diversions     */
int ilevel = 0; 		/* input file stack pointer    */
int oindex = 0; 		/* diversion index..	       */
char *null = "";                /* as it says.. just a null..  */
char *m4wraps = "";             /* m4wrap string default..     */
char *progname;			/* name of this program        */
char lquote[MAXCCHARS+1] = {LQUOTE};	/* left quote character  (`)   */
char rquote[MAXCCHARS+1] = {RQUOTE};	/* right quote character (')   */
char scommt[MAXCCHARS+1] = {SCOMMT};	/* start character for comment */
char ecommt[MAXCCHARS+1] = {ECOMMT};	/* end character for comment   */

struct keyblk keywrds[] = {	/* m4 keywords to be installed */
	"include",      INCLTYPE,
	"sinclude",     SINCTYPE,
	"define",       DEFITYPE,
	"defn",         DEFNTYPE,
	"divert",       DIVRTYPE,
	"expr",         EXPRTYPE,
	"eval",         EXPRTYPE,
	"substr",       SUBSTYPE,
	"ifelse",       IFELTYPE,
	"ifdef",        IFDFTYPE,
	"len",          LENGTYPE,
	"incr",         INCRTYPE,
	"decr",         DECRTYPE,
	"dnl",          DNLNTYPE,
	"changequote",  CHNQTYPE,
	"changecom",    CHNCTYPE,
	"index",        INDXTYPE,
#ifdef EXTENDED
	"paste",        PASTTYPE,
	"spaste",       SPASTYPE,
#endif
	"popdef",       POPDTYPE,
	"pushdef",      PUSDTYPE,
	"dumpdef",      DUMPTYPE,
	"shift",        SHIFTYPE,
	"translit",     TRNLTYPE,
	"undefine",     UNDFTYPE,
	"undivert",     UNDVTYPE,
	"divnum",       DIVNTYPE,
	"maketemp",     MKTMTYPE,
	"errprint",     ERRPTYPE,
	"m4wrap",       M4WRTYPE,
	"m4exit",       EXITTYPE,
	"syscmd",       SYSCTYPE,
	"sysval",       SYSVTYPE,

#if defined(unix) || defined(__NetBSD__) || defined(__OpenBSD__)
	"unix",         MACRTYPE,
#else
#ifdef vms
	"vms",          MACRTYPE,
#endif
#endif
};

#define MAXKEYS	(sizeof(keywrds)/sizeof(struct keyblk))

extern int optind;
extern char *optarg;

void macro();
void initkwds();
extern int getopt();

int
main(argc,argv)
	int argc;
	char *argv[];
{
	register int c;
	register int n;
	char *p;
	register FILE *ifp;

	progname = basename(argv[0]);

	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
		signal(SIGINT, onintr);

	initkwds();

	while ((c = getopt(argc, argv, "tD:U:o:")) != -1)
		switch(c) {

		case 'D':               /* define something..*/
			for (p = optarg; *p; p++)
				if (*p == '=')
					break;
			if (*p)
				*p++ = EOS;
			dodefine(optarg, p);
			break;
		case 'U':               /* undefine...       */
			remhash(optarg, TOP);
			break;
		case 'o':		/* specific output   */
		case '?':
			usage();
		}

        argc -= optind;
        argv += optind;

	active = stdout;		/* default active output     */
					/* filename for diversions   */
	m4temp = mktemp(xstrdup(_PATH_DIVNAME));

	bbase[0] = bufbase;
        if (!argc) {
 		sp = -1;		/* stack pointer initialized */
		fp = 0; 		/* frame pointer initialized */
		infile[0] = stdin;	/* default input (naturally) */
		macro();
	} else
		for (; argc--; ++argv) {
			p = *argv;
			if (p[0] == '-' && p[1] == '\0')
				ifp = stdin;
			else if ((ifp = fopen(p, "r")) == NULL)
				oops("%s: %s", p, strerror(errno));
			sp = -1;
			fp = 0; 
			infile[0] = ifp;
			macro();
			if (ifp != stdin)
				(void)fclose(ifp);
		}

	if (*m4wraps) { 		/* anything for rundown ??   */
		ilevel = 0;		/* in case m4wrap includes.. */
		bufbase = bp = buf;	/* use the entire buffer   */
		putback(EOF);		/* eof is a must !!	     */
		pbstr(m4wraps); 	/* user-defined wrapup act   */
		macro();		/* last will and testament   */
	}

	if (active != stdout)
		active = stdout;	/* reset output just in case */
	for (n = 1; n < MAXOUT; n++)	/* default wrap-up: undivert */
		if (outfile[n] != NULL)
			getdiv(n);
					/* remove bitbucket if used  */
	if (outfile[0] != NULL) {
		(void) fclose(outfile[0]);
		m4temp[UNIQUE] = '0';
#ifdef vms
		(void) remove(m4temp);
#else
		(void) unlink(m4temp);
#endif
	}

	return 0;
}

ndptr inspect();

/*
 * Look ahead (at most MAXCCHARS characters) for `token'.
 * (on input `t == token[0]')
 * Used for comment and quoting delimiters.
 * Returns 1 if `token' present; copied to output.
 *         0 if `token' not found; all characters pushed back
 */
int
do_look_ahead(t, token)
	int	t;
	char	*token;
{
	int i;

	if (t != token[0])
		oops("internal error", "");

	for (i = 1; *++token; i++) {
		t = gpbc();
		if (t == EOF || t != *token) {
			if (t != EOF)
				putback(t);
			while (--i)
				putback(*--token);
			return 0;
		}
	}
	return 1;
}

#define LOOK_AHEAD(t, token) ((t)==(token)[0] && do_look_ahead(t,token))

/*
 * macro - the work horse..
 */
void
macro() {
	char token[MAXTOK];
	register char *s;
	register int t, l;
	register ndptr p;
	register int  nlpar;

	cycle {
		t = gpbc();
		if (t == '_' || isalpha(t)) {
			putback(t);
			if ((p = inspect(s = token)) == nil) {
				if (sp < 0)
					while (*s)
						putc(*s++, active);
				else
					while (*s)
						chrsave(*s++);
			}
			else {
		/*
		 * real thing.. First build a call frame:
		 */
				pushf(fp);	/* previous call frm */
				pushf(p->type); /* type of the call  */
				pushf(0);	/* parenthesis level */
				fp = sp;	/* new frame pointer */
		/*
		 * now push the string arguments:
		 */
				pushs(p->defn);	      /* defn string */
				pushs(p->name);	      /* macro name  */
				pushs(ep);	      /* start next..*/

				putback(l = gpbc());
				if (l != LPAREN)  {   /* add bracks  */
					putback(RPAREN);
					putback(LPAREN);
				}
			}
		}
		else if (t == EOF) {
			if (sp > -1)
				oops("unexpected end of input", "");
			if (ilevel <= 0)
				break;			/* all done thanks.. */
			--ilevel;
			(void) fclose(infile[ilevel+1]);
			bufbase = bbase[ilevel];
			continue;
		}
	/*
	 * non-alpha single-char token seen..
	 * [the order of else if .. stmts is important.]
	 */
		else if (LOOK_AHEAD(t,lquote)) {	/* strip quotes */
			nlpar = 1;
			do {
				l = gpbc();
				if (LOOK_AHEAD(l,rquote))
					nlpar--;
				else if (LOOK_AHEAD(l,lquote))
					nlpar++;
				else if (l == EOF)
					oops("missing right quote", "");
				if (nlpar > 0) {
					if (sp < 0)
						putc(l, active);
					else
						chrsave(l);
				}
			}
			while (nlpar != 0);
		}

		else if (sp < 0 && LOOK_AHEAD(t, scommt)) {
			int i;
			for (i = 0; i < MAXCCHARS && scommt[i]; i++)
				putc(scommt[i], active);

			for(;;) {
				t = gpbc();
				if (LOOK_AHEAD(t, ecommt)) {
					for (i = 0; i < MAXCCHARS && ecommt[i];
					     i++)
						putc(ecommt[i], active);
					break;
				}
				if (t == EOF)
					break;
				putc(t, active);
			}
		}

		else if (sp < 0) {		/* not in a macro at all */
			putc(t, active);	/* output directly..	 */
		}

		else switch(t) {

		case LPAREN:
			if (PARLEV > 0)
				chrsave(t);
			while (isspace(l = gpbc()))
				;		/* skip blank, tab, nl.. */
			putback(l);
			PARLEV++;
			break;

		case RPAREN:
			if (--PARLEV > 0)
				chrsave(t);
			else {			/* end of argument list */
				chrsave(EOS);

				if (sp == STACKMAX)
					oops("internal stack overflow", "");

				if (CALTYP == MACRTYPE)
					expand((char **) mstack+fp+1, sp-fp);
				else
					eval((char **) mstack+fp+1, sp-fp, CALTYP);

				ep = PREVEP;	/* flush strspace */
				sp = PREVSP;	/* previous sp..  */
				fp = PREVFP;	/* rewind stack...*/
			}
			break;

		case COMMA:
			if (PARLEV == 1) {
				chrsave(EOS);		/* new argument   */
				while (isspace(l = gpbc()))
					;
				putback(l);
				pushs(ep);
			} else
				chrsave(t);
			break;

		default:
			chrsave(t);			/* stack the char */
			break;
		}
	}
}

/*
 * build an input token..
 * consider only those starting with _ or A-Za-z. This is a
 * combo with lookup to speed things up.
 */
ndptr
inspect(tp) 
register char *tp;
{
	register char c;
	register char *name = tp;
	register char *etp = tp+MAXTOK;
	register ndptr p;
	register unsigned long h = 0;

	while ((isalnum(c = gpbc()) || c == '_') && tp < etp)
		h = (h << 5) + h + (*tp++ = c);
	putback(c);
	if (tp == etp)
		oops("token too long", "");

	*tp = EOS;

	for (p = hashtab[h%HASHSIZE]; p != nil; p = p->nxtptr)
		if (STREQ(name, p->name))
			break;
	return p;
}

/*
 * initkwds - initialise m4 keywords as fast as possible. 
 * This very similar to install, but without certain overheads,
 * such as calling lookup. Malloc is not used for storing the 
 * keyword strings, since we simply use the static  pointers
 * within keywrds block.
 */
void
initkwds() {
	register int i;
	register int h;
	register ndptr p;

	for (i = 0; i < MAXKEYS; i++) {
		h = hash(keywrds[i].knam);
		p = (ndptr) xalloc(sizeof(struct ndblock));
		p->nxtptr = hashtab[h];
		hashtab[h] = p;
		p->name = keywrds[i].knam;
		p->defn = null;
		p->type = keywrds[i].ktyp | STATIC;
	}
}