ref: c9a50478a9b995cf12d91edb32cf9e4dda528a31
dir: /decl.c/
#include <assert.h> #include <stddef.h> #include <string.h> #include "sizes.h" #include "cc.h" #include "tokens.h" #include "syntax.h" #include "symbol.h" char parser_out_home; /* * Number of nested declarations: * Number of nested struct declarations * +1 for the function declaration * +1 for the field declaration */ static struct symbol *symstack[NR_STRUCT_LEVEL + 1 + 1], **symstackp = symstack; static struct symbol *cursym; static unsigned char nr_tags = NS_TAG; static unsigned char nested_tags; static void declarator(struct ctype *tp, unsigned char ns); static void directdcl(register struct ctype *tp, unsigned char ns) { if (accept('(')) { declarator(tp, ns); expect(')'); } else if (yytoken == IDEN) { /* we can't overflow due to the check in structdcl */ *symstackp++ = cursym = lookup(yytext, ns); if (!cursym->ctype) cursym->ctx = curctx; else if (cursym->ctx == curctx) error("redeclaration of '%s'", yytext); next(); } else { error("expected '(' or identifier before of '%s'", yytext); } for (;;) { if (accept('(')) { pushtype(FTN); if (accept(')')) ; /* TODO: k&r function */ else /* TODO: prototyped function */; } else if (accept('[')) { unsigned len; if (accept(']')) { len = 0; } else { expect(CONSTANT); len = yyval->i; expect(']'); } pushtype(len); pushtype(ARY); } else { return; } } } static void aggregate(register struct ctype *tp) { struct symbol *sym = NULL; if (yytoken == IDEN) { sym = lookup(yytext, NS_TAG); sym->ctype = tp; next(); } if (nr_tags == NS_TAG + NR_MAXSTRUCTS) error("too much structs/unions/enum defined"); tp->ns = ++nr_tags; tp->forward = 1; tp->sym = sym; } static bool specifier(register struct ctype *, struct storage *, struct qualifier *); static void fielddcl(unsigned char ns) { struct ctype base; struct storage store; struct qualifier qlf; register struct ctype *tp; initctype(&base); initstore(&store); initqlf(&qlf); specifier(&base, &store, &qlf); if (store.defined) error("storage specifier in a struct/union field declaration"); do { declarator(&base, ns); tp = decl_type(&base); if (accept(':')) { expect(CONSTANT); switch (tp->type) { case INT: case BOOL: tp = ctype(NULL, BITFLD); tp->len = yyval->i; break; default: error("bit-field '%s' has invalid type", cursym->name); } } cursym->ctype = tp; cursym->qlf = qlf; } while (accept(',')); expect(';'); } static void structdcl(register struct ctype *tp) { aggregate(tp); if (nested_tags == NR_STRUCT_LEVEL) error("too much nested structs/unions"); ++nested_tags; if (!accept('{')) return; if (!tp->forward) error("struct/union already defined"); do fielddcl(tp->ns); while (!accept('}')); --nested_tags; tp->forward = 0; } static void enumdcl(struct ctype *base) { short val = 0; aggregate(base); if (!accept('{')) return; do { register struct symbol *sym; register struct ctype *tp = ctype(NULL, INT); if (yytoken != IDEN) break; sym = lookup(yytext, NS_IDEN); sym->ctype = tp; next(); if (accept('=')) { expect(CONSTANT); val = yyval->i; } sym->i = val++; } while (accept(',')); expect('}'); } bool specifier(register struct ctype *tp, struct storage *store, struct qualifier *qlf) { for (;; next()) { switch (yytoken) { case CONST: case VOLATILE: qlf = qualifier(qlf, yytoken); break; case TYPEDEF: case EXTERN: case STATIC: case AUTO: case REGISTER: store = storage(store, yytoken); break; case UNSIGNED: case SIGNED: case COMPLEX: case IMAGINARY: case FLOAT: case DOUBLE: case BOOL: case VOID: case CHAR: case SHORT: case INT: case LONG: tp = ctype(tp, yytoken); break; case ENUM: tp = ctype(tp, yytoken); next(); enumdcl(tp); return true; case STRUCT: case UNION: tp = ctype(tp, yytoken); next(); structdcl(tp); return true; case IDEN: if (!tp->defined) { register struct symbol *sym; sym = lookup(yytext, NS_IDEN); if (sym->ctype && sym->store.c_typedef) { tp = ctype(tp, TYPEDEF); tp->base = sym->ctype; break; } } /* it is not a type name */ default: goto check_type; } } check_type: if (!tp->defined) { if (!store->defined && !qlf->defined && curctx != CTX_OUTER && nested_tags == 0) { return false; } warn(options.implicit, "type defaults to 'int' in declaration"); } if (nested_tags > 0 && (qlf->defined || store->defined)) error("type qualifer or store specifier in field declaration"); if (!tp->c_signed && !tp->c_unsigned) { switch (tp->type) { case CHAR: if (!options.charsign) { case BOOL: tp->c_unsigned = 1; break; } case INT: case SHORT: case LONG: case LLONG: tp->c_signed = 1; } } return true; } static void declarator(struct ctype *tp, unsigned char ns) { unsigned char qlf[NR_DECLARATORS]; register unsigned char *bp, *lim; lim = &qlf[NR_DECLARATORS]; for (bp = qlf; yytoken == '*' && bp != lim; ) { next(); *bp++ = PTR; while (bp != lim) { switch (yytoken) { case CONST: case VOLATILE: case RESTRICT: *bp++ = yytoken; next(); break; default: goto continue_outer; } } continue_outer: ; } if (bp == lim) error("Too much type declarators"); directdcl(tp, ns); for (lim = bp, bp = qlf; bp < lim; ++bp) pushtype(*bp); } static struct node * initializer(register struct ctype *tp) { if (!accept('=')) return NULL; next(); if (accept('{')) { struct compound c; c.tree = NULL; addstmt(&c, initializer(tp)); while (accept(',')) { if (accept('}')) return c.tree; addstmt(&c, initializer(tp)); } expect('}'); return c.tree; } else { return expr(); } } static struct node * listdcl(struct ctype *base, struct storage *store, struct qualifier *qlf) { struct compound c; char fun; c.tree = NULL; do { struct node *np, *aux; register struct ctype *tp; declarator(base, NS_IDEN); cursym->store = *store; cursym->qlf = *qlf; tp = cursym->ctype = decl_type(base); if ((tp->type == STRUCT || tp->type == UNION) && tp->forward) error("declaration of variable with incomplete type"); np = nodesym(cursym); fun = tp->type == FTN && yytoken == '{'; aux = fun ? function(cursym) : initializer(tp); addstmt(&c, node(ODEF, np, aux)); cursym = *--symstackp; } while (!fun && accept(',')); if (!fun) expect(';'); return c.tree; } struct node * decl(void) { struct ctype base; struct storage store; struct qualifier qlf; struct node *np; repeat: initctype(&base); initstore(&store); initqlf(&qlf); if (!specifier(&base, &store, &qlf)) return NULL; if (accept(';')) { register unsigned char type = base.type; switch (type) { case STRUCT: case UNION: case ENUM: if (store.defined) { warn(options.useless, "useless storage class specifier in empty declaration"); } if (qlf.defined) { warn(options.useless, "useless type qualifier in empty declaration"); } if (base.sym && type != ENUM) { warn(options.useless, "unnamed struct/union that defines no instances"); } default: warn(options.useless, "useless type name in empty declaration"); } goto repeat; } np = listdcl(&base, &store, &qlf); return np; } void type_name() { }