458 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			458 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * main.c
 | 
						|
 * Facility: m4 macro processor
 | 
						|
 * by: oz
 | 
						|
 */
 | 
						|
 | 
						|
#include "mdef.h"
 | 
						|
 | 
						|
/*
 | 
						|
 * m4 - macro processor
 | 
						|
 *
 | 
						|
 * PD m4 is based on the macro tool distributed with the software 
 | 
						|
 * tools (VOS) package, and described in the "SOFTWARE TOOLS" and 
 | 
						|
 * "SOFTWARE TOOLS IN PASCAL" books. It has been expanded to include 
 | 
						|
 * most of the command set of SysV m4, the standard UN*X macro processor.
 | 
						|
 *
 | 
						|
 * Since both PD m4 and UN*X m4 are based on SOFTWARE TOOLS macro,
 | 
						|
 * there may be certain implementation similarities between
 | 
						|
 * the two. The PD m4 was produced without ANY references to m4
 | 
						|
 * sources.
 | 
						|
 *
 | 
						|
 * References:
 | 
						|
 *
 | 
						|
 *	Software Tools distribution: macro
 | 
						|
 *
 | 
						|
 *	Kernighan, Brian W. and P. J. Plauger, SOFTWARE
 | 
						|
 *	TOOLS IN PASCAL, Addison-Wesley, Mass. 1981
 | 
						|
 *
 | 
						|
 *	Kernighan, Brian W. and P. J. Plauger, SOFTWARE
 | 
						|
 *	TOOLS, Addison-Wesley, Mass. 1976
 | 
						|
 *
 | 
						|
 *	Kernighan, Brian W. and Dennis M. Ritchie,
 | 
						|
 *	THE M4 MACRO PROCESSOR, Unix Programmer's Manual,
 | 
						|
 *	Seventh Edition, Vol. 2, Bell Telephone Labs, 1979
 | 
						|
 *
 | 
						|
 *	System V man page for M4
 | 
						|
 *
 | 
						|
 * Modification History:
 | 
						|
 *
 | 
						|
 * Jan 28 1986 Oz	Break the whole thing into little
 | 
						|
 *			pieces, for easier (?) maintenance.
 | 
						|
 *
 | 
						|
 * Dec 12 1985 Oz	Optimize the code, try to squeeze
 | 
						|
 *			few microseconds out..
 | 
						|
 *
 | 
						|
 * Dec 05 1985 Oz	Add getopt interface, define (-D),
 | 
						|
 *			undefine (-U) options.
 | 
						|
 *
 | 
						|
 * Oct 21 1985 Oz	Clean up various bugs, add comment handling.
 | 
						|
 *
 | 
						|
 * June 7 1985 Oz	Add some of SysV m4 stuff (m4wrap, pushdef,
 | 
						|
 *			popdef, decr, shift etc.).
 | 
						|
 *
 | 
						|
 * June 5 1985 Oz	Initial cut.
 | 
						|
 *
 | 
						|
 * Implementation Notes:
 | 
						|
 *
 | 
						|
 * [1]	PD m4 uses a different (and simpler) stack mechanism than the one 
 | 
						|
 *	described in Software Tools and Software Tools in Pascal books. 
 | 
						|
 *	The triple stack nonsense is replaced with a single stack containing 
 | 
						|
 *	the call frames and the arguments. Each frame is back-linked to a 
 | 
						|
 * 	previous stack frame, which enables us to rewind the stack after 
 | 
						|
 * 	each nested call is completed. Each argument is a character pointer 
 | 
						|
 *	to the beginning of the argument string within the string space.
 | 
						|
 *	The only exceptions to this are (*) arg 0 and arg 1, which are
 | 
						|
 * 	the macro definition and macro name strings, stored dynamically
 | 
						|
 *	for the hash table.
 | 
						|
 *
 | 
						|
 *	    .					   .
 | 
						|
 *	|   .	|  <-- sp			|  .  |
 | 
						|
 *	+-------+				+-----+
 | 
						|
 *	| arg 3 ------------------------------->| str |
 | 
						|
 *	+-------+				|  .  |
 | 
						|
 *	| arg 2 --------------+ 		   .
 | 
						|
 *	+-------+	      |
 | 
						|
 *	    *		      |			|     |
 | 
						|
 *	+-------+	      | 		+-----+
 | 
						|
 *	| plev	|  <-- fp     +---------------->| str |
 | 
						|
 *	+-------+				|  .  |
 | 
						|
 *	| type	|				   .
 | 
						|
 *	+-------+
 | 
						|
 *	| prcf	-----------+		plev: paren level
 | 
						|
 *	+-------+  	   |		type: call type
 | 
						|
 *	|   .	| 	   |		prcf: prev. call frame
 | 
						|
 *	    .	   	   |
 | 
						|
 *	+-------+	   |
 | 
						|
 *	|	<----------+
 | 
						|
 *	+-------+
 | 
						|
 *
 | 
						|
 * [2]	We have three types of null values:
 | 
						|
 *
 | 
						|
 *		nil  - nodeblock pointer type 0
 | 
						|
 *		null - null string ("")
 | 
						|
 *		NULL - Stdio-defined NULL
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
ndptr hashtab[HASHSIZE];	/* hash table for macros etc.  */
 | 
						|
char buf[BUFSIZE];		/* push-back buffer	       */
 | 
						|
char *bp = buf; 		/* first available character   */
 | 
						|
char *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 lquote = LQUOTE;		/* left quote character  (`)   */
 | 
						|
char rquote = RQUOTE;		/* right quote character (')   */
 | 
						|
char scommt = SCOMMT;		/* start character for comment */
 | 
						|
char ecommt = 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,
 | 
						|
#if unix || vms
 | 
						|
	"syscmd",       SYSCTYPE,
 | 
						|
	"sysval",       SYSVTYPE,
 | 
						|
#endif
 | 
						|
#if unix
 | 
						|
	"unix",         MACRTYPE,
 | 
						|
#else
 | 
						|
#if vms
 | 
						|
	"vms",          MACRTYPE,
 | 
						|
#endif
 | 
						|
#endif
 | 
						|
};
 | 
						|
 | 
						|
#define MAXKEYS	(sizeof(keywrds)/sizeof(struct keyblk))
 | 
						|
 | 
						|
extern int optind;
 | 
						|
extern char *optarg;
 | 
						|
 | 
						|
int main(argc,argv)
 | 
						|
int argc;
 | 
						|
char *argv[];
 | 
						|
{
 | 
						|
	register int c;
 | 
						|
	register int n;
 | 
						|
	char *p;
 | 
						|
	static char divnam[] = DIVNAM;
 | 
						|
 | 
						|
	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
 | 
						|
		signal(SIGINT, onintr);
 | 
						|
#ifdef NONZEROPAGES
 | 
						|
	initm4();
 | 
						|
#endif
 | 
						|
	initkwds();
 | 
						|
 | 
						|
	while ((c = getopt(argc, argv, "tD:U:o:")) != EOF) {
 | 
						|
		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 '?':
 | 
						|
		default:
 | 
						|
			usage();
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	argc -= optind;
 | 
						|
	argv += optind;
 | 
						|
 | 
						|
	if(argc > 1) { usage(); }
 | 
						|
	infile[0] = stdin;		/* default input (naturally) */
 | 
						|
	if(argc == 1) {
 | 
						|
		if(!(infile[0] = fopen(argv[0], "r"))) {
 | 
						|
			perror(argv[0]);
 | 
						|
			return 1;
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	active = stdout;		/* default active output     */
 | 
						|
	m4temp = mktemp(divnam);	/* filename for diversions   */
 | 
						|
 | 
						|
	sp = -1;			/* stack pointer initialized */
 | 
						|
	fp = 0; 			/* frame pointer initialized */
 | 
						|
 | 
						|
	macro();			/* get some work done here   */
 | 
						|
 | 
						|
	if (*m4wraps) { 		/* anything for rundown ??   */
 | 
						|
		ilevel = 0;		/* in case m4wrap includes.. */
 | 
						|
		putback(EOF);		/* eof is a must !!	     */
 | 
						|
		pbstr(m4wraps); 	/* user-defined wrapup act   */
 | 
						|
		macro();		/* last will and testament   */
 | 
						|
	}
 | 
						|
	else				/* default wrap-up: undivert */
 | 
						|
		for (n = 1; n < MAXOUT; n++)
 | 
						|
			if (outfile[n] != NULL)
 | 
						|
				getdiv(n);
 | 
						|
 | 
						|
					/* remove bitbucket if used  */
 | 
						|
	if (outfile[0] != NULL) {
 | 
						|
		(void) fclose(outfile[0]);
 | 
						|
		m4temp[UNIQUE] = '0';
 | 
						|
#if vms
 | 
						|
		(void) remove(m4temp);
 | 
						|
#else
 | 
						|
		(void) unlink(m4temp);
 | 
						|
#endif
 | 
						|
	}
 | 
						|
 | 
						|
	exit(0);
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * macro - the work horse..
 | 
						|
 *
 | 
						|
 */
 | 
						|
void macro() {
 | 
						|
	char token[MAXTOK];
 | 
						|
	register char *s;
 | 
						|
	register int t, l;
 | 
						|
	register ndptr p;
 | 
						|
	register int  nlpar;
 | 
						|
 | 
						|
	cycle {
 | 
						|
		if ((t = gpbc()) == '_' || 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)
 | 
						|
				error("m4: unexpected end of input");
 | 
						|
			if (--ilevel < 0)
 | 
						|
				break;			/* all done thanks.. */
 | 
						|
			(void) fclose(infile[ilevel+1]);
 | 
						|
			continue;
 | 
						|
		}
 | 
						|
	/*
 | 
						|
	 * non-alpha single-char token seen..
 | 
						|
	 * [the order of else if .. stmts is
 | 
						|
	 * important.]
 | 
						|
	 *
 | 
						|
	 */
 | 
						|
		else if (t == lquote) { 		/* strip quotes */
 | 
						|
			nlpar = 1;
 | 
						|
			do {
 | 
						|
				if ((l = gpbc()) == rquote)
 | 
						|
					nlpar--;
 | 
						|
				else if (l == lquote)
 | 
						|
					nlpar++;
 | 
						|
				else if (l == EOF)
 | 
						|
					error("m4: missing right quote");
 | 
						|
				if (nlpar > 0) {
 | 
						|
					if (sp < 0)
 | 
						|
						putc(l, active);
 | 
						|
					else
 | 
						|
						chrsave(l);
 | 
						|
				}
 | 
						|
			}
 | 
						|
			while (nlpar != 0);
 | 
						|
		}
 | 
						|
 | 
						|
		else if (sp < 0) {		/* not in a macro at all */
 | 
						|
			if (t == scommt) {	/* comment handling here */
 | 
						|
				putc(t, active);
 | 
						|
				while ((t = gpbc()) != ecommt)
 | 
						|
					putc(t, active);
 | 
						|
			}
 | 
						|
			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)
 | 
						|
					error("m4: internal stack overflow");
 | 
						|
 | 
						|
				if (CALTYP == MACRTYPE)
 | 
						|
					expand((char**)mstack+fp+1,(int)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);
 | 
						|
			}
 | 
						|
			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 int h = 0;
 | 
						|
	register char c;
 | 
						|
	register char *name = tp;
 | 
						|
	register char *etp = tp+MAXTOK;
 | 
						|
	register ndptr p;
 | 
						|
 | 
						|
	while (tp < etp && (isalnum(c = gpbc()) || c == '_'))
 | 
						|
		h += (*tp++ = c);
 | 
						|
	putback(c);
 | 
						|
	if (tp == etp)
 | 
						|
		error("m4: token too long");
 | 
						|
	*tp = EOS;
 | 
						|
	for (p = hashtab[h%HASHSIZE]; p != nil; p = p->nxtptr)
 | 
						|
		if (strcmp(name, p->name) == 0)
 | 
						|
			break;
 | 
						|
	return(p);
 | 
						|
}
 | 
						|
 | 
						|
#ifdef NONZEROPAGES
 | 
						|
/*
 | 
						|
 * initm4 - initialize various tables. Useful only if your system 
 | 
						|
 * does not know anything about demand-zero pages.
 | 
						|
 *
 | 
						|
 */
 | 
						|
void initm4()
 | 
						|
{
 | 
						|
	register int i;
 | 
						|
 | 
						|
	for (i = 0; i < HASHSIZE; i++)
 | 
						|
		hashtab[i] = nil;
 | 
						|
	for (i = 0; i < MAXOUT; i++)
 | 
						|
		outfile[i] = NULL;
 | 
						|
}
 | 
						|
#endif
 | 
						|
 | 
						|
/*
 | 
						|
 * 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. We also assume that there is enough memory 
 | 
						|
 * to at least install the keywords (i.e. malloc won't fail).
 | 
						|
 *
 | 
						|
 */
 | 
						|
void initkwds() {
 | 
						|
	register int i;
 | 
						|
	register int h;
 | 
						|
	register ndptr p;
 | 
						|
 | 
						|
	for (i = 0; i < MAXKEYS; i++) {
 | 
						|
		h = hash(keywrds[i].knam);
 | 
						|
		p = (ndptr) malloc(sizeof(struct ndblock));
 | 
						|
		p->nxtptr = hashtab[h];
 | 
						|
		hashtab[h] = p;
 | 
						|
		p->name = keywrds[i].knam;
 | 
						|
		p->defn = null;
 | 
						|
		p->type = keywrds[i].ktyp | STATIC;
 | 
						|
	}
 | 
						|
}
 |