cpp.c

unix v7是最后一个广泛发布的研究型UNIX版本

	/* copy to avoid running off end of world when param list is at end */
	p=buf; while (*p++= *s++);
	p=buf; while (isid(*p++)); /* skip first identifier */
	if (*--p=='=') {*p++=' '; while (*p++);}
	else {s=" 1"; while (*p++= *s++);}
	pend=p; *--p='\n';
	sloscan(); dodef(buf); return(lastsym);
}

struct symtab *
ppsym(s) char *s; {/* kluge */
	register struct symtab *sp;
	cinit=SALT; *savch++=SALT; sp=stsym(s); --sp->name; cinit=0; return(sp);
}

/* VARARGS1 */
pperror(s,x,y) char *s; {
	if (fnames[ifno][0]) fprintf(stderr,
# if gcos
			"*%c*   \"%s\", line ", exfail >= 0 ? 'F' : 'W',
# else
			"%s: ",
# endif
				 fnames[ifno]);
	fprintf(stderr, "%d: ",lineno[ifno]);
	fprintf(stderr, s, x, y);
	fprintf(stderr,"\n");
	++exfail;
}

yyerror(s,a,b) char *s; {
	pperror(s,a,b);
}

ppwarn(s,x) char *s; {
	int fail = exfail;
	exfail = -1;
	pperror(s,x);
	exfail = fail;
}

struct symtab *
lookup(namep, enterf)
char *namep;
{
	register char *np, *snp;
	register int c, i; int around;
	register struct symtab *sp;

	/* namep had better not be too long (currently, <=8 chars) */
	np=namep; around=0; i=cinit;
	while (c= *np++) i += i+c; c=i;	/* c=i for register usage on pdp11 */
	c %= symsiz; if (c<0) c += symsiz;
	sp = &stab[c];
	while (snp=sp->name) {
		np = namep;
		while (*snp++ == *np) if (*np++ == '\0') {
				if (enterf==DROP) {sp->name[0]= DROP; sp->value=0;}
				return(lastsym=sp);
			}
		if (--sp < &stab[0])
			if (around) {pperror("too many defines", 0); exit(exfail);}
			else {++around; sp = &stab[symsiz-1];}
	}
	if (enterf>0) sp->name=namep;
	return(lastsym=sp);
}

struct symtab *
slookup(p1,p2,enterf) register char *p1,*p2; int enterf;{
	register char *p3; char c2,c3; struct symtab *np;
	         c2= *p2; *p2='\0';	/* mark end of token */
	if ((p2-p1)>8) p3=p1+8; else p3=p2;
			 c3= *p3; *p3='\0';	/* truncate to 8 chars or less */
	if (enterf==1) p1=copy(p1);
	np=lookup(p1,enterf); *p3=c3; *p2=c2;
	if (np->value!=0 && flslvl==0) newp=subst(p2,np);
	else newp=0;
	return(np);
}

char *
subst(p,sp) register char *p; struct symtab *sp; {
	static char match[]="%s: argument mismatch";
	register char *ca,*vp; int params;
	char *actual[MAXFRM]; /* actual[n] is text of nth actual */
	char acttxt[BUFSIZ]; /* space for actuals */

	if (0==(vp=sp->value)) return(p);
	if ((p-macforw)<=macdam) {
		if (++maclvl>symsiz && !rflag) {
			pperror("%s: macro recursion",sp->name); return(p);
		}
	} else maclvl=0;	/* level decreased */
	macforw=p; macdam=0;	/* new target for decrease in level */
	macnam=sp->name;
	dump();
	if (sp==ulnloc) {
		vp=acttxt; *vp++='\0';
		sprintf(vp,"%d",lineno[ifno]); while (*vp++);
	} else if (sp==uflloc) {
		vp=acttxt; *vp++='\0';
		sprintf(vp,"\"%s\"",fnames[ifno]); while (*vp++);
	}
	if (0!=(params= *--vp&0xFF)) {/* definition calls for params */
		register char **pa;
		ca=acttxt; pa=actual;
		if (params==0xFF) params=1;	/* #define foo() ... */
		sloscan(); ++flslvl; /* no expansion during search for actuals */
		plvl= -1;
		do p=skipbl(p); while (*inp=='\n');	/* skip \n too */
		if (*inp=='(') {
			maclin=lineno[ifno]; macfil=fnames[ifno];
			for (plvl=1; plvl!=0; ) {
				*ca++='\0';
				for (;;) {
					outp=inp=p; p=cotoken(p);
					if (*inp=='(') ++plvl;
					if (*inp==')' && --plvl==0) {--params; break;}
					if (plvl==1 && *inp==',') {--params; break;}
					while (inp<p) *ca++= *inp++;
					if (ca> &acttxt[BUFSIZ])
						pperror("%s: actuals too long",sp->name);
				}
				if (pa>= &actual[MAXFRM]) ppwarn(match,sp->name);
				else *pa++=ca;
			}
		}
		if (params!=0) ppwarn(match,sp->name);
		while (--params>=0) *pa++=""+1;	/* null string for missing actuals */
		--flslvl; fasscan();
	}
	for (;;) {/* push definition onto front of input stack */
		while (!iswarn(*--vp)) {
			if (bob(p)) {outp=inp=p; p=unfill(p);}
			*--p= *vp;
		}
		if (*vp==warnc) {/* insert actual param */
			ca=actual[*--vp-1];
			while (*--ca) {
				if (bob(p)) {outp=inp=p; p=unfill(p);}
				*--p= *ca;
			}
		} else break;
	}
	outp=inp=p;
	return(p);
}




char *
trmdir(s) register char *s; {
	register char *p = s;
	while (*p++); --p; while (p>s && *--p!='/');
# if unix
	if (p==s) *p++='.';
# endif
	*p='\0';
	return(s);
}

STATIC char *
copy(s) register char *s; {
	register char *old;

	old = savch; while (*savch++ = *s++);
	return(old);
}

char *
strdex(s,c) char *s,c; {
	while (*s) if (*s++==c) return(--s);
	return(0);
}

yywrap(){ return(1); }

main(argc,argv)
	char *argv[];
{
	register int i,c;
	register char *p;
	char *tf,**cp2;

# if gcos
	if (setjmp(env)) return (exfail);
# endif
	p="_ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
		i=0;
		while (c= *p++) {
			(fastab+COFF)[c] |= IB|NB|SB; (toktyp+COFF)[c]=IDENT;
#if scw2
			/* 53 == 63-10; digits rarely appear in identifiers,
			/* and can never be the first char of an identifier.
			/* 11 == 53*53/sizeof(macbit) .
			*/
			++i; (t21+COFF)[c]=(53*i)/11; (t22+COFF)[c]=i%11;
#endif
		}
	p="0123456789.";
		while (c= *p++) {(fastab+COFF)[c] |= NB|SB; (toktyp+COFF)[c]=NUMBR;}
# if gcos
	p="\n\"'`/\\";
# else
	p="\n\"'/\\";
# endif
		while (c= *p++) (fastab+COFF)[c] |= SB;
# if gcos
	p="\n\"'`\\";
# else
	p="\n\"'\\";
# endif
		while (c= *p++) (fastab+COFF)[c] |= QB;
	p="*\n"; while (c= *p++) (fastab+COFF)[c] |= CB;
	(fastab+COFF)[warnc] |= WB;
	(fastab+COFF)['\0'] |= CB|QB|SB|WB;
	for (i=ALFSIZ; --i>=0; ) slotab[i]=fastab[i]|SB;
	p=" \t\013\f\r";	/* note no \n;	\v not legal for vertical tab? */
		while (c= *p++) (toktyp+COFF)[c]=BLANK;
#if scw2
	for ((t23+COFF)[i=ALFSIZ+7-COFF]=1; --i>=-COFF; )
		if (((t23+COFF)[i]=(t23+COFF+1)[i]<<1)==0) (t23+COFF)[i]=1;
#endif

# if unix
	fnames[ifno=0] = "";
# endif
# if ibm
	fnames[ifno=0] = "";
# endif
# if gcos
	if (inquire(stdin, _TTY)) freopen("*src", "rt", stdin);
# endif
# if gimpel || gcos
	fnames[ifno=0] = (char *)inquire(stdin, _FILENAME);
	dirnams[0] = dirs[0] = trmdir(copy(fnames[0]));
# endif
	for(i=1; i<argc; i++)
		{
		switch(argv[i][0])
			{
			case '-':
# if gcos
			switch(toupper(argv[i][1])) { /* case-independent on GCOS */
# else
			switch(argv[i][1]) {
# endif
				case 'P': pflag++;
				case 'E': continue;
				case 'R': ++rflag; continue;
				case 'C': passcom++; continue;
				case 'D':
					if (predef>prespc+NPREDEF) {
						pperror("too many -D options, ignoring %s",argv[i]);
						continue;
					}
					/* ignore plain "-D" (no argument) */
					if (*(argv[i]+2)) *predef++ = argv[i]+2;
					continue;
				case 'U':
					if (prund>punspc+NPREDEF) {
						pperror("too many -U options, ignoring %s",argv[i]);
						continue;
					}
					*prund++ = argv[i]+2;
					continue;
				case 'I':
					if (nd>8) pperror("excessive -I file (%s) ignored",argv[i]);
					else dirs[nd++] = argv[i]+2;
					continue;
				case '\0': continue;
				default: 
					pperror("unknown flag %s", argv[i]);
					continue;
				}
			default:
				if (fin==STDIN) {
					if (0>(fin=open(argv[i], READ))) {
						pperror("No source file %s",argv[i]); exit(8);
					}
					fnames[ifno]=copy(argv[i]);
					dirs[0]=dirnams[ifno]=trmdir(argv[i]);
# ifndef gcos
/* too dangerous to have file name in same syntactic position
   be input or output file depending on file redirections,
   so force output to stdout, willy-nilly
	[i don't see what the problem is.  jfr]
*/
				} else if (fout==stdout) {
					extern char _sobuf[BUFSIZ];
					if (NULL==(fout=fopen(argv[i], "w"))) {
						pperror("Can't create %s", argv[i]); exit(8);
					} else {fclose(stdout); setbuf(fout,_sobuf);}
# endif
				} else pperror("extraneous name %s", argv[i]);
			}
		}

	fins[ifno]=fin;
	exfail = 0;
		/* after user -I files here are the standard include libraries */
# if unix
	dirs[nd++] = "/usr/include";
# endif
# if gcos
	dirs[nd++] = "cc/include";
# endif
# if ibm
# ifndef gimpel
	dirs[nd++] = "BTL$CLIB";
# endif
# endif
# ifdef gimpel
	dirs[nd++] = intss() ?  "SYS3.C." : "" ;
# endif
	/* dirs[nd++] = "/compool"; */
	dirs[nd++] = 0;
	defloc=ppsym("define");
	udfloc=ppsym("undef");
	incloc=ppsym("include");
	elsloc=ppsym("else");
	eifloc=ppsym("endif");
	ifdloc=ppsym("ifdef");
	ifnloc=ppsym("ifndef");
	ifloc=ppsym("if");
	lneloc=ppsym("line");
	for (i=sizeof(macbit)/sizeof(macbit[0]); --i>=0; ) macbit[i]=0;
# if unix
	ysysloc=stsym("unix");
# endif
# if gcos
	ysysloc=stsym ("gcos");
# endif
# if ibm
	ysysloc=stsym ("ibm");
# endif
# if pdp11
	varloc=stsym("pdp11");
# endif
# if vax
	varloc=stsym("vax");
# endif
# if interdata
	varloc=stsym ("interdata");
# endif
# if tss
	varloc=stsym ("tss");
# endif
# if os
	varloc=stsym ("os");
# endif
# if mert
	varloc=stsym ("mert");
# endif
	ulnloc=stsym ("__LINE__");
	uflloc=stsym ("__FILE__");

	tf=fnames[ifno]; fnames[ifno]="command line"; lineno[ifno]=1;
	cp2=prespc;
	while (cp2<predef) stsym(*cp2++);
	cp2=punspc;
	while (cp2<prund) {
		if (p=strdex(*cp2, '=')) *p++='\0';
		lookup(*cp2++, DROP);
	}
	fnames[ifno]=tf;
	pbeg=buffer+8; pbuf=pbeg+BUFSIZ; pend=pbuf+BUFSIZ;

	trulvl = 0; flslvl = 0;
	lineno[0] = 1; sayline();
	outp=inp=pend;
	control(pend);
	return (exfail);
}