ref: c1d40df49550393f3afe53fb6e6d500dfa8eb7a8
dir: /sys/src/cmd/cpp/macro.c/
#include <u.h> #include <libc.h> #include <stdio.h> #include "cpp.h" /* * do a macro definition. tp points to the name being defined in the line */ void dodefine(Tokenrow *trp) { Token *tp; Nlist *np; Tokenrow *def, *args; int dots; dots = 0; tp = trp->tp+1; if (tp>=trp->lp || tp->type!=NAME) { error(ERROR, "#defined token is not a name"); return; } np = lookup(tp, 1); if (np->flag&ISUNCHANGE) { error(ERROR, "#defined token %t can't be redefined", tp); return; } /* collect arguments */ tp += 1; args = NULL; if (tp<trp->lp && tp->type==LP && tp->wslen==0) { /* macro with args */ int narg = 0; tp += 1; args = new(Tokenrow); maketokenrow(2, args); if (tp->type!=RP) { int err = 0; for (;;) { Token *atp; if (tp->type == ELLIPS) dots++; else if (tp->type!=NAME) { err++; break; } if (narg>=args->max) growtokenrow(args); for (atp=args->bp; atp<args->lp; atp++) if (atp->len==tp->len && strncmp((char*)atp->t, (char*)tp->t, tp->len)==0) error(ERROR, "Duplicate macro argument"); *args->lp++ = *tp; narg++; tp += 1; if (tp->type==RP) break; if (dots) error(ERROR, "arguments after '...' in macro"); if (tp->type!=COMMA) { err++; break; } tp += 1; } if (err) { error(ERROR, "Syntax error in macro parameters"); return; } } tp += 1; } trp->tp = tp; if (((trp->lp)-1)->type==NL) trp->lp -= 1; def = normtokenrow(trp); if (np->flag&ISDEFINED) { if (comparetokens(def, np->vp) || (np->ap==NULL) != (args==NULL) || np->ap && comparetokens(args, np->ap)) error(ERROR, "Macro redefinition of %t", trp->bp+2); } if (args) { Tokenrow *tap; tap = normtokenrow(args); dofree(args->bp); args = tap; } np->ap = args; np->vp = def; np->flag |= ISDEFINED; if(dots) np->flag |= ISVARMAC; } /* * Definition received via -D or -U */ void doadefine(Tokenrow *trp, int type) { Nlist *np; static unsigned char one[] = "1"; static Token onetoken[1] = {{ NUMBER, 0, 0, 0, 1, one }}; static Tokenrow onetr = { onetoken, onetoken, onetoken+1, 1 }; trp->tp = trp->bp; if (type=='U') { if (trp->lp-trp->tp != 2 || trp->tp->type!=NAME) goto syntax; if ((np = lookup(trp->tp, 0)) == NULL) return; np->flag &= ~ISDEFINED; return; } if (trp->tp >= trp->lp || trp->tp->type!=NAME) goto syntax; np = lookup(trp->tp, 1); np->flag |= ISDEFINED; trp->tp += 1; if (trp->tp >= trp->lp || trp->tp->type==END) { np->vp = &onetr; return; } if (trp->tp->type!=ASGN) goto syntax; trp->tp += 1; if ((trp->lp-1)->type == END) trp->lp -= 1; np->vp = normtokenrow(trp); return; syntax: error(FATAL, "Illegal -D or -U argument %r", trp); } /* * Do macro expansion in a row of tokens. * Flag is NULL if more input can be gathered. */ void expandrow(Tokenrow *trp, char *flag) { Token *tp; Nlist *np; if (flag) setsource(flag, -1, ""); for (tp = trp->tp; tp<trp->lp; ) { if (tp->type!=NAME || quicklook(tp->t[0], tp->len>1?tp->t[1]:0)==0 || (np = lookup(tp, 0))==NULL || (np->flag&(ISDEFINED|ISMAC))==0 || tp->hideset && checkhideset(tp->hideset, np)) { tp++; continue; } trp->tp = tp; if (np->val==KDEFINED) { tp->type = DEFINED; if ((tp+1)<trp->lp && (tp+1)->type==NAME) (tp+1)->type = NAME1; else if ((tp+3)<trp->lp && (tp+1)->type==LP && (tp+2)->type==NAME && (tp+3)->type==RP) (tp+2)->type = NAME1; else error(ERROR, "Incorrect syntax for `defined'"); tp++; continue; } if (np->flag&ISMAC) builtin(trp, np->val); else expand(trp, np); tp = trp->tp; } if (flag) unsetsource(); } /* * Expand the macro whose name is np, at token trp->tp, in the tokenrow. * Return trp->tp at the first token next to be expanded * (ordinarily the beginning of the expansion) */ void expand(Tokenrow *trp, Nlist *np) { int ntokc, narg, i, hs; Tokenrow *atr[NARG+1]; Tokenrow ntr; Token *tp; copytokenrow(&ntr, np->vp); /* copy macro value */ if (np->ap==NULL) { /* parameterless */ ntokc = 1; /* substargs for handling # and ## */ atr[0] = nil; substargs(np, &ntr, atr, trp->tp->hideset); } else { ntokc = gatherargs(trp, atr, (np->flag&ISVARMAC) ? rowlen(np->ap) : 0, &narg); if (narg<0) { /* not actually a call (no '(') */ /* gatherargs has already pushed trp->tr to the next token */ return; } if (narg != rowlen(np->ap)) { error(ERROR, "Disagreement in number of macro arguments"); trp->tp->hideset = newhideset(trp->tp->hideset, np); trp->tp += ntokc; return; } substargs(np, &ntr, atr, trp->tp->hideset); /* put args into replacement */ for (i=0; i<narg; i++) { dofree(atr[i]->bp); dofree(atr[i]); } } hs = newhideset(trp->tp->hideset, np); for (tp=ntr.bp; tp<ntr.lp; tp++) { /* distribute hidesets */ if (tp->type==NAME) { if (tp->hideset==0) tp->hideset = hs; else tp->hideset = unionhideset(tp->hideset, hs); } } ntr.tp = ntr.bp; insertrow(trp, ntokc, &ntr); trp->tp -= rowlen(&ntr); free(ntr.bp); } /* * Gather an arglist, starting in trp with tp pointing at the macro name. * Return total number of tokens passed, stash number of args found. * trp->tp is not changed relative to the tokenrow. */ int gatherargs(Tokenrow *trp, Tokenrow **atr, int dots, int *narg) { int parens = 1; int ntok = 0; Token *bp, *lp; Tokenrow ttr; int ntokp; int needspace; *narg = -1; /* means that there is no macro call */ /* look for the ( */ for (;;) { trp->tp++; ntok++; if (trp->tp >= trp->lp) { gettokens(trp, 0); if ((trp->lp-1)->type==END) { trp->lp -= 1; if (*narg>=0) trp->tp -= ntok; return ntok; } } if (trp->tp->type==LP) break; if (trp->tp->type!=NL) return ntok; } *narg = 0; ntok++; ntokp = ntok; trp->tp++; /* search for the terminating ), possibly extending the row */ needspace = 0; while (parens>0) { if (trp->tp >= trp->lp) gettokens(trp, 0); if (needspace) { needspace = 0; makespace(trp); } if (trp->tp->type==END) { trp->lp -= 1; trp->tp -= ntok; error(ERROR, "EOF in macro arglist"); return ntok; } if (trp->tp->type==NL) { trp->tp += 1; adjustrow(trp, -1); trp->tp -= 1; makespace(trp); needspace = 1; continue; } if (trp->tp->type==LP) parens++; else if (trp->tp->type==RP) parens--; trp->tp++; ntok++; } trp->tp -= ntok; /* Now trp->tp won't move underneath us */ lp = bp = trp->tp+ntokp; for (; parens>=0; lp++) { if (lp->type == LP) { parens++; continue; } if (lp->type==RP) parens--; if (lp->type==DSHARP) lp->type = DSHARP1; /* ## not special in arg */ if ((lp->type==COMMA && parens==0) || (parens<0 && (lp-1)->type!=LP)) { if (lp->type == COMMA && dots && *narg == dots-1) continue; if (*narg>=NARG-1) error(FATAL, "Sorry, too many macro arguments"); ttr.bp = ttr.tp = bp; ttr.lp = lp; atr[(*narg)++] = normtokenrow(&ttr); bp = lp+1; } } return ntok; } int ispaste(Tokenrow *rtr, Token **ap, Token **an, int *ntok) { *ap = nil; *an = nil; /* EMPTY ## tok */ if (rtr->tp->type == DSHARP && rtr->tp != rtr->bp) rtr->tp--; /* tok ## tok */ if(rtr->tp + 1 != rtr->lp && rtr->tp[1].type == DSHARP) { *ap = rtr->tp; if(rtr->tp + 2 != rtr->lp) *an = rtr->tp + 2; *ntok = 1 + (*ap != nil) + (*an != nil); return 1; } return 0; } /* * substitute the argument list into the replacement string * This would be simple except for ## and # */ void substargs(Nlist *np, Tokenrow *rtr, Tokenrow **atr, int hideset) { Tokenrow ttr, rp, rn; Token *tp, *ap, *an, *pp, *pn; int ntok, argno, hs; for (rtr->tp=rtr->bp; rtr->tp<rtr->lp; ) { if(rtr->tp->hideset && checkhideset(hideset, np)) { rtr->tp++; } else if (rtr->tp->type==SHARP) { /* string operator */ tp = rtr->tp; rtr->tp += 1; if ((argno = lookuparg(np, rtr->tp))<0) { error(ERROR, "# not followed by macro parameter"); continue; } ntok = 1 + (rtr->tp - tp); rtr->tp = tp; insertrow(rtr, ntok, stringify(atr[argno])); } else if (ispaste(rtr, &ap, &an, &ntok)) { /* first token, just do the next one */ pp = ap; memset(&rp, 0, sizeof(rp)); pn = an; memset(&rn, 0, sizeof(rp)); if (ap && (argno = lookuparg(np, ap)) >= 0){ pp = nil; rp = *atr[argno]; if(rp.tp != rp.lp) pp = --rp.lp; } if (an && (argno = lookuparg(np, an)) >= 0) { pn = nil; rn = *atr[argno]; if(rn.tp != rn.lp) pn = rn.bp++; } glue(&ttr, pp, pn); insertrow(rtr, 0, &rp); insertrow(rtr, ntok, &ttr); insertrow(rtr, 0, &rn); free(ttr.bp); } else if (rtr->tp->type==NAME) { if((argno = lookuparg(np, rtr->tp)) >= 0) { if (rtr->tp < rtr->bp) { error(ERROR, "access out of bounds"); continue; } copytokenrow(&ttr, atr[argno]); expandrow(&ttr, "<macro>"); insertrow(rtr, 1, &ttr); free(ttr.bp); } else { maketokenrow(1, &ttr); ttr.lp = ttr.tp + 1; *ttr.tp = *rtr->tp; hs = newhideset(rtr->tp->hideset, np); if(hideset == 0) ttr.tp->hideset = hs; else ttr.tp->hideset = unionhideset(hideset, hs); expandrow(&ttr, (char*)np->name); for(tp = ttr.bp; tp != ttr.lp; tp++) if(tp->type == COMMA) tp->type = XCOMMA; insertrow(rtr, 1, &ttr); dofree(ttr.bp); } } else { rtr->tp++; } } } /* * Evaluate the ## operators in a tokenrow */ void glue(Tokenrow *ntr, Token *tp, Token *tn) { int np, nn; char *tt, *p, *n; np = tp ? tp->len : 0; nn = tn ? tn->len : 0; tt = domalloc(np + nn + 1); if(tp) memcpy(tt, tp->t, tp->len); if(tn) memcpy(tt+np, tn->t, tn->len); tt[np+nn] = '\0'; setsource("<##>", -1, tt); maketokenrow(3, ntr); gettokens(ntr, 1); unsetsource(); dofree(tt); if (np + nn == 0) { ntr->lp = ntr->bp; } else { if (ntr->lp - ntr->bp!=2 || ntr->bp->type==UNCLASS) { p = tp ? (char*)tp->t : "<empty>"; n = tn ? (char*)tn->t : "<empty>"; error(WARNING, "Bad token %r produced by %s ## %s", &ntr, p, n); } ntr->lp = ntr->bp+1; } makespace(ntr); } /* * tp is a potential parameter name of macro mac; * look it up in mac's arglist, and if found, return the * corresponding index in the argname array. Return -1 if not found. */ int lookuparg(Nlist *mac, Token *tp) { Token *ap; if (tp->type!=NAME || mac->ap==NULL) return -1; if((mac->flag & ISVARMAC) && strcmp((char*)tp->t, "__VA_ARGS__") == 0) return rowlen(mac->ap) - 1; for (ap=mac->ap->bp; ap<mac->ap->lp; ap++) { if (ap->len==tp->len && strncmp((char*)ap->t,(char*)tp->t,ap->len)==0) return ap - mac->ap->bp; } return -1; } /* * Return a quoted version of the tokenrow (from # arg) */ #define STRLEN 512 Tokenrow * stringify(Tokenrow *vp) { static Token t = { STRING }; static Tokenrow tr = { &t, &t, &t+1, 1 }; Token *tp; uchar s[STRLEN]; uchar *sp = s, *cp; int i, instring; *sp++ = '"'; for (tp = vp->bp; tp < vp->lp; tp++) { instring = tp->type==STRING || tp->type==CCON; if (sp+2*tp->len >= &s[STRLEN-10]) { error(ERROR, "Stringified macro arg is too long"); break; } if (tp->wslen && (tp->flag&XPWS)==0) *sp++ = ' '; for (i=0, cp=tp->t; i<tp->len; i++) { if (instring && (*cp=='"' || *cp=='\\')) *sp++ = '\\'; *sp++ = *cp++; } } *sp++ = '"'; *sp = '\0'; sp = s; t.len = strlen((char*)sp); t.t = newstring(sp, t.len, 0); return &tr; } /* * expand a builtin name */ void builtin(Tokenrow *trp, int biname) { char *op; Token *tp; Source *s; tp = trp->tp; trp->tp++; /* need to find the real source */ s = cursource; while (s && s->fd==-1) s = s->next; if (s==NULL) s = cursource; /* most are strings */ tp->type = STRING; if (tp->wslen) { *outp++ = ' '; tp->wslen = 1; } op = outp; *op++ = '"'; switch (biname) { case KLINENO: tp->type = NUMBER; op = outnum(op-1, s->line); break; case KFILE: strcpy(op, s->filename); op += strlen(s->filename); break; case KDATE: strncpy(op, curtime+4, 7); strncpy(op+7, curtime+24, 4); /* Plan 9 asctime disobeys standard */ op += 11; break; case KTIME: strncpy(op, curtime+11, 8); op += 8; break; default: error(ERROR, "cpp botch: unknown internal macro"); return; } if (tp->type==STRING) *op++ = '"'; tp->t = (uchar*)outp; tp->len = op - outp; outp = op; }