ref: e61db29e0aed115dc504d337b8006e869cc5040c
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 unsigned char nr_tags = NS_TAG;
static unsigned char nested_tags;
static struct symbol *declarator(struct ctype *tp, unsigned char ns);
static struct symbol *
directdcl(register struct ctype *tp, unsigned char ns)
{
register struct symbol *sym;
register char *err;
if (accept('(')) {
sym = declarator(tp, ns);
expect(')');
} else if (ns != NS_TYPE) {
if (yytoken == IDEN) {
sym = lookup(yytext, ns);
if (!sym->ctype.defined)
sym->ctx = curctx;
else if (sym->ctx == curctx)
goto redeclared;
next();
} else {
goto expected;
}
}
for (;;) {
if (accept('(')) {
pushtype(FTN);
if (yytoken != ')')
; /* TODO: prototyped function */;
expect(')');
} else if (accept('[')) {
unsigned len = '0';
if (yytoken != ']') {
expect(CONSTANT);
len = yyval->i;
}
expect(']');
pushtype(len);
pushtype(ARY);
} else {
return sym;
}
}
redeclared:
err = "redeclaration of '%s'";
goto error;
expected:
err = "expected '(' or identifier before of '%s'";
error: error(err, yytext);
}
static unsigned char
newtag(unsigned char type)
{
if (type == ENUM)
return 0;
if (nr_tags == NS_TAG + NR_MAXSTRUCTS)
error("too much structs/unions defined");
return ++nr_tags;
}
static struct symbol *
aggregate(register struct ctype *tp)
{
struct symbol *sym = NULL;
tp->forward = 1;
if (yytoken == IDEN) {
register struct ctype *aux;
sym = lookup(yytext, NS_TAG);
aux = &sym->ctype;
if (aux->defined) {
if (aux->type != tp->type)
goto bad_type;
*tp = *aux;
} else {
tp->tag = sym->name;
tp->ns = newtag(tp->type);
sym->ctype = *tp;
}
next();
} else {
tp->ns = newtag(tp->type);
}
return sym;
bad_type:
error("'%s' defined as wrong kind of tag", yytext);
}
static void
structdcl(register struct ctype *tp)
{
struct symbol *sym;
sym = aggregate(tp);
if (!accept('{'))
return;
if (sym && !sym->ctype.forward)
error("struct/union already defined");
if (nested_tags == NR_STRUCT_LEVEL)
error("too much nested structs/unions");
++nested_tags;
while (!accept('}'))
decl(tp->ns);
--nested_tags;
if (sym)
sym->ctype.forward = 0;
tp->forward = 0;
}
static void
enumdcl(struct ctype *base)
{
static int val;
aggregate(base);
if (!accept('{'))
return;
val = 0;
do {
register struct symbol *sym;
register struct ctype *tp;
if (yytoken != IDEN)
break;
sym = lookup(yytext, NS_IDEN);
tp = &sym->ctype;
if (tp->defined && sym->ctx == curctx)
error("'%s' redefined", yytext);
next();
if (accept('=')) {
expect(CONSTANT);
val = yyval->i;
}
ctype(tp, INT);
tp->base = base;
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, ENUM);
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.defined &&
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 (!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 struct symbol *
declarator(struct ctype *tp, unsigned char ns)
{
unsigned char qlf[NR_DECLARATORS];
register unsigned char *bp;
register unsigned char n = 0;
struct symbol *sym;
if (yytoken == '*') {
for (bp = qlf; n < NR_DECLARATORS ; ++n) {
switch (yytoken) {
case '*':
yytoken = PTR;
case CONST: case VOLATILE: case RESTRICT:
*bp++ = yytoken;
next();
continue;
default:
goto direct;
}
}
error("Too much type declarators");
}
direct: sym = directdcl(tp, ns);
for (bp = qlf; n--; pushtype(*bp++))
/* nothing */;
return sym;
}
static struct node *
initializer(register struct ctype *tp)
{
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, unsigned char ns)
{
struct compound c;
char *err;
c.tree = NULL;
do {
struct node *np, *aux;
register struct ctype *tp;
register struct symbol *sym;
sym = declarator(base, ns);
sym->store = *store;
sym->qlf = *qlf;
sym->ctype = *decl_type(base);
tp = &sym->ctype;
aux = NULL;
switch (tp->type) {
case FTN:
if (ns != NS_IDEN)
goto bad_type;
if (yytoken == '{') {
if (curctx != CTX_OUTER)
goto local_fun;
aux = function(sym);
addstmt(&c, node(ODEF, nodesym(sym), aux));
return c.tree;
}
goto add_stmt;
case INT: case BOOL:
if (ns != NS_IDEN && accept(':')) {
expect(CONSTANT);
tp = ctype(NULL, BITFLD);
tp->len = yyval->i;
goto add_stmt;
}
goto add_init;
case STRUCT: case UNION:
if (tp->forward)
goto incomplete;
default:
add_init:
if (ns == NS_IDEN) {
if (accept('='))
aux = initializer(tp);
}
add_stmt:
addstmt(&c, node(ODEF, nodesym(sym), aux));
}
} while (accept(','));
expect(';');
return c.tree;
bad_type:
err = "incorrect type for field";
goto error;
local_fun:
err = "cannot use local functions";
goto error;
incomplete:
err = "declaration of variable with incomplete type";
error: error(err);
}
struct node *
decl(unsigned char ns)
{
struct ctype base;
struct storage store;
struct qualifier qlf;
repeat: initctype(&base);
initstore(&store);
initqlf(&qlf);
if (!specifier(&base, &store, &qlf))
return NULL;
if (store.defined && ns != NS_IDEN)
error("storage specifier in a struct/union field declaration");
if (accept(';')) {
register unsigned char type = base.type;
switch (type) {
case STRUCT: case UNION:
if (!base.tag) {
warn(options.useless,
"unnamed struct/union that defines no instances");
}
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 (ns == NS_IDEN)
break;
default:
warn(options.useless,
"useless type name in empty declaration");
}
if (yytoken == EOFTOK)
return NULL;
goto repeat;
}
return listdcl(&base, &store, &qlf, ns);
}
bool
type_name(struct ctype *tp)
{
struct storage store;
struct qualifier qlf;
initctype(tp);
initstore(&store);
initqlf(&qlf);
if (!specifier(tp, &store, &qlf))
return false;
declarator(tp, NS_TYPE);
return true;
}