static struct block *cast_expression(struct block *block)
{
struct typetree *type;
struct token tok;
struct symbol *sym;
/* This rule needs two lookahead; to see beyond the initial parenthesis if
* it is actually a cast or an expression. */
if (peek().token == '(') {
tok = peekn(2);
switch (tok.token) {
case IDENTIFIER:
sym = sym_lookup(&ns_ident, tok.strval);
if (!sym || sym->symtype != SYM_TYPEDEF)
break;
case FIRST(type_name):
consume('(');
type = declaration_specifiers(NULL);
if (peek().token != ')') {
type = declarator(type, NULL);
}
consume(')');
block = cast_expression(block);
block->expr = eval_cast(block, block->expr, type);
return block;
default:
break;
}
}
return unary_expression(block);
}
TOKEN parameter_declaration(void)
{
SYMBOL s = symalloc();
TOKEN dec = NULL;
declaration_specifiers(s);
dec = declarator(s);
set_token_symbol_type(dec,s);
return dec;
}
void declaratorlist(void){
declarator();
while(lookahead == ','){
match(',');
declarator();
}
}
int function_definition(void) {
if( declaration_specifiers() ) {
declarator();
if( declaration_list() ) {
}
} else if ( declarator() ) {
if( declaration_list() ) {
}
} else {
abort();
}
compound_statement();
}
/**
形参列表
<parameter_type_list>::=<type_specifier>{<declarator>}
{<TK_COMMA><type_specifier>{<declarator>}}<TK_COMMA><TK_ELLIPSIS>
*/
void parameter_type_list(){
int func_call; /// 原书将这个变量当做参数
get_token();
while(TK_CLOSEPA != token){
if(!type_specifier())
error("invalid identifier");
declarator();
if(TK_CLOSEPA == token)
break;
skip(TK_COMMA);
if(TK_ELLIPSIS == token){
func_call = KW_CDECL;
get_token();
break;
}
}
syntax_state = SNTX_DELAY;
skip(TK_CLOSEPA);
get_token();
if(TK_BEGIN == token) /// define function
syntax_state = SNTX_LF_HT;
else
syntax_state = SNTX_NUL;
syntax_indent();
}
/**
@brief 解析外部命令
@param l 存储类型，局部的or全局的
*/
void external_declaration(int l){
if(!type_specifier()){
expect("<类型区分符>");
}
if(token == TK_SEMICOLON){
get_token();
return;
}
while(1){
declarator();
if(token == TK_BEGIN){
if(l == SC_LOCAL){
error("不支持函数嵌套定义");
}
funcbody();
break;
}else{
if(token == TK_ASSIGN){
get_token();
initializer();
}
if(token == TK_COMMA){
get_token();
}else{
syntax_state = SNTX_LE_HT;
skip(TK_SEMICOLON);
break;
}
}
}
}
/**
外部声明
<external_declaration>::=<type_specifier>(<TK_SEMICOLON>
|<declarator><funcbody>
|<declarator>[<TK_ASSIGN><initializer>]
{TK_COMMA><declarator>[<TK_ASSIGN><initializer>]}<TK_SEMICOLON>
)
DO:parse external statement
storage type:local | global
*/
void external_declaration(int l){
if(!type_specifier())
expect("<Type specifier>");
if(token == TK_SEMICOLON){
get_token();
return;
}
while(1){
declarator();
if(token == TK_BEGIN){
if(l == SC_LOCAL)
error("don't support function nesting define");
funcbody();
break;
}else {
if(token == TK_ASSIGN){
get_token();
initializer();
}
if(token == TK_COMMA)
get_token();
else{
syntax_state = SNTX_LF_HT;
skip(TK_SEMICOLON);
break;
}
}
}
}
int parameter_list(ParserState* ps) {
if (curris(ps, PLParen)) {
enterblk();
while (ps->curr != 0) {
VVar id;
if (!declarator(ps, &id))
parerr(ps, "invalid parameter syntax");
if (curris(ps, PComma)) {
Ast* comma = ps->curr;
if (comma->next != 0) {
ast_swap(comma, comma->next);
ast_rmnext(comma);
}
}
else if (ps->curr != 0) {
parerr(ps, "expecting \',\' in parameter list");
}
}
exitblk();
return 1;
}
else return 0;
}
int init_declarator(void) {
declarator();
if( lookaheadT.type == EQUAL ) {
match(EQUAL);
initializer();
}
}
int declaration(char* result)
{
char token[MAXTOKEN];
char token2[MAXTOKEN];
bool is_const = false;
int type = -1;
int ret = 0;
ret -= try_tokens_until(&type, token, try_declaration, try_declarator,
"Missing data type to form a declaration");
if (type == NAME) {
if (gettoken(token2) == CONST) {
// T const XXX
is_const = true;
} else {
unget_token();
}
} else if (type == CONST) {
is_const = true;
ret -= try_tokens_until(&type, token, try_name, try_declarator,
"Missing data type to form a declaration");
}
ret += declarator(result);
strcat(result, " ");
if (is_const) {
strcat(result, "const ");
}
strcat(result, token);
return ret;
}
static void
params(CTy *fty)
{
int sclass;
CTy *t;
char *name;
SrcPos *pos;
fty->Func.isvararg = 0;
if(tok->k == ')')
return;
for(;;) {
pos = &tok->pos;
t = declspecs(&sclass);
t = declarator(t, &name, 0);
if(sclass != SCNONE)
errorposf(pos, "storage class not allowed in parameter decl");
vecappend(fty->Func.params, newnamety(name, t));
if(tok->k != ',')
break;
next();
}
if(tok->k == TOKELLIPSIS) {
fty->Func.isvararg = 1;
next();
}
}
/*----------------------------------------------------------------------------*/
void
c_semantic::free_declarator(c_context & context, c_token token)
{
if (1 == options.verbose_flag) {
printf("## c_semantic::free_declarator()\n\n");
}
if (NO_CLASS_STATUS !=
context.class_specifier_status) {
printf
("error c_semantic::free_declarator() NO_CLASS_STATUS != context.class_specifier_status\n\n");
exit(-1);
}
c_declarator declarator(token, vector_decl_specifier);
context.declarator = declarator;
/*
template <class myType>
myType GetMax (myType a, myType b) {
return (a>b?a:b);
}
we are in GetMax line ...
*/
if ( TEMPLATE_DECLARATION == context.template_status ) {
context.declarator.is_template = 1;
}
}
static CTy *
directdeclarator(CTy *basety, char **name)
{
CTy *ty, *stub;
*name = 0;
switch(tok->k) {
case '(':
expect('(');
stub = gcmalloc(sizeof(CTy));
*stub = *basety;
ty = declarator(stub, name, 0);
expect(')');
*stub = *declaratortail(basety);
return ty;
case TOKIDENT:
if(name)
*name = tok->v;
next();
return declaratortail(basety);
default:
if(!name)
errorposf(&tok->pos, "expected ident or ( but got %s", tokktostr(tok->k));
return declaratortail(basety);
}
errorf("unreachable");
return 0;
}
static void param_declarator(node_t ** ty, struct token **id)
{
if (token->id == '*') {
node_t *pty = ptr_decl();
prepend_type(ty, pty);
}
if (token->id == '(') {
if (first_decl(lookahead())) {
abstract_declarator(ty);
} else {
node_t *type1 = *ty;
node_t *rtype = NULL;
expect('(');
param_declarator(&rtype, id);
expect(')');
if (token->id == '(' || token->id == '[') {
node_t *faty;
cc_assert(id);
if (*id) {
faty = func_or_array(false, NULL);
} else {
faty = func_or_array(true, NULL);
}
attach_type(&faty, type1);
attach_type(&rtype, faty);
}
*ty = rtype;
}
} else if (token->id == '[') {
abstract_declarator(ty);
} else if (token->id == ID) {
declarator(ty, id, NULL);
}
}
/* Declarator is what introduces names into the program. */
static CTy *
declarator(CTy *basety, char **name, Node **init)
{
CTy *t;
while (tok->k == TOKCONST || tok->k == TOKVOLATILE)
next();
switch(tok->k) {
case '*':
next();
basety = mkptr(basety);
t = declarator(basety, name, init);
return t;
default:
t = directdeclarator(basety, name);
if(tok->k == '=') {
if(!init)
errorposf(&tok->pos, "unexpected initializer");
next();
*init = declinit();
} else {
if(init)
*init = 0;
}
return t;
}
}
static int variable_decl(ParserState* ps) {
Ast* rvar = ps->curr;
if (stepifis(ps, RVar)) {
int count = 0;
while (count == 0 || curris(ps, PComma)) {
if (stepifis(ps, PComma)) free(ast_rmnext(rvar));
VVar id;
if (declarator(ps, &id)) {
ast_next_to_last_child(rvar);
}
else {
parerr(ps, "invalid declarator");
break;
}
count++;
}
if (!stepifis(ps, PSemi)) {
parerr(ps, "expecting ',' or ';'");
}
return 1;
}
else return 0;
}
static Node *
decl()
{
Node *n, *init;
char *name;
CTy *type, *basety;
SrcPos *pos;
Sym *sym;
Vec *syms;
int sclass;
pos = &tok->pos;
syms = vec();
basety = declspecs(&sclass);
while(tok->k != ';' && tok->k != TOKEOF) {
type = declarator(basety, &name, &init);
switch(sclass){
case SCNONE:
if(isglobal()) {
sclass = SCGLOBAL;
} else {
sclass = SCAUTO;
}
break;
case SCTYPEDEF:
if(init)
errorposf(pos, "typedef cannot have an initializer");
break;
}
if(!name)
errorposf(pos, "decl needs to specify a name");
sym = definesym(pos, sclass, name, type, init);
vecappend(syms, sym);
if(isglobal() && tok->k == '{') {
if(init)
errorposf(pos, "function declaration has an initializer");
if(type->t != CFUNC)
errorposf(pos, "expected a function");
curfunc = mknode(NFUNC, pos);
curfunc->type = type;
curfunc->Func.name = name;
curfunc->Func.params = vec();
curfunc->Func.stkslots = vec();
fbody();
definesym(pos, sclass, name, type, curfunc);
curfunc = 0;
goto done;
}
if(tok->k == ',')
next();
else
break;
}
expect(';');
done:
n = mknode(NDECL, pos);
n->Decl.syms = syms;
return n;
}
int struct_declarator(void) {
if( declarator() ) {
}
if( lookaheadT.type == COLON ) {
match(COLON);
constant_expression();
}
}
static void fields(node_t * sym)
{
int follow[] = {INT, CONST, '}', IF, 0};
node_t *sty = SYM_TYPE(sym);
if (!first_decl(token)) {
error("expect type name or qualifiers");
return;
}
struct vector *v = vec_new();
do {
node_t *basety = specifiers(NULL, NULL);
for (;;) {
node_t *field = new_field();
if (token->id == ':') {
bitfield(field);
FIELD_TYPE(field) = basety;
} else {
node_t *ty = NULL;
struct token *id = NULL;
declarator(&ty, &id, NULL);
attach_type(&ty, basety);
if (token->id == ':')
bitfield(field);
FIELD_TYPE(field) = ty;
if (id) {
for (int i = 0; i < vec_len(v); i++) {
node_t *f = vec_at(v, i);
if (FIELD_NAME(f) &&
!strcmp(FIELD_NAME(f), id->name)) {
errorf(id->src,
"redefinition of '%s'",
id->name);
break;
}
}
FIELD_NAME(field) = id->name;
AST_SRC(field) = id->src;
}
}
vec_push(v, field);
if (token->id != ',')
break;
expect(',');
ensure_field(field, vec_len(v), false);
}
match(';', follow);
ensure_field(vec_tail(v), vec_len(v),
isstruct(sty) && !first_decl(token));
} while (first_decl(token));
TYPE_FIELDS(sty) = (node_t **) vtoa(v);
set_typesize(sty);
}
/**
结构声明
<struct_declaration>::=
<type_specifier><declarator>{<TK_COMMA><declarator>}
<TK_SEMICOLON>
*/
void struct_declaration(){
type_specifier();
while(1){
declarator();
if(token == TK_SEMICOLON)
break;
skip(TK_COMMA);
}
syntax_state = SNTX_LF_HT;
skip(TK_SEMICOLON);
}
/* Parse function and array declarators. Some trickery is needed to handle
* declarations like `void (*foo)(int)`, where the inner *foo has to be
* traversed first, and prepended on the outer type `* (int) -> void`
* afterwards making it `* (int) -> void`.
* The type returned from declarator has to be either array, function or
* pointer, thus only need to check for type->next to find inner tail.
*/
static struct typetree *direct_declarator(
struct typetree *base,
const char **symbol)
{
struct typetree *type = base;
struct typetree *head, *tail = NULL;
struct token ident;
switch (peek().token) {
case IDENTIFIER:
ident = consume(IDENTIFIER);
if (!symbol) {
error("Unexpected identifier in abstract declarator.");
exit(1);
}
*symbol = ident.strval;
break;
case '(':
consume('(');
type = head = tail = declarator(NULL, symbol);
while (tail->next) {
tail = (struct typetree *) tail->next;
}
consume(')');
break;
default:
break;
}
while (peek().token == '[' || peek().token == '(') {
switch (peek().token) {
case '[':
type = direct_declarator_array(base);
break;
case '(':
consume('(');
type = parameter_list(base);
consume(')');
break;
default:
assert(0);
}
if (tail) {
tail->next = type;
type = head;
}
base = type;
}
return type;
}
/*----------------------------------------------------------------------------*/
void c_semantic::identifier_typedef(c_context & context, c_token token)
{
if (1 == options.verbose_flag) {
printf("## void c_semantic::identifier_typedef(c_token token) token.text[%s]\n\n",token.text.c_str());
}
/*
## it must search in the stack
stack 0
class A{};
stack 1
int A;
typedef class A t_A;
typedef vector < c_decl_specifier > t_vector_decl_specifier;
*/
if ( 0 != context.class_name_declaration.size() ) {
c_symbol symbol(token);
symbol.is_typedef = 1;
symbol.typedef_points_to = context.class_name_declaration;
symbol.type = TYPEDEF_NAME;
if ( 1 == context.is_template_instantiation ) {
symbol.is_template_instantiation = context.is_template_instantiation;
symbol.vector_template_argument = context.vector_template_argument;
symbol.map_template_argument = context.map_template_argument;
}
ts.insert(symbol);
}
if (NO_CLASS_STATUS ==
context.class_specifier_status) {
c_declarator declarator(token, vector_decl_specifier);
declarator.is_typedef = 1;
if ( 1 == context.is_template_instantiation ) {
declarator.is_template_instantiation = context.is_template_instantiation;
declarator.vector_template_argument = context.vector_template_argument;
declarator.map_template_argument = context.map_template_argument;
}
context.declarator = declarator;
}
}
/* Parse call to builtin symbol __builtin_va_arg, which is the result of calling
* va_arg(arg, T). Return type depends on second input argument.
*/
static struct block *parse__builtin_va_arg(struct block *block)
{
struct typetree *type;
consume('(');
block = assignment_expression(block);
consume(',');
type = declaration_specifiers(NULL);
if (peek().token != ')') {
type = declarator(type, NULL);
}
consume(')');
block->expr = eval__builtin_va_arg(block, block->expr, type);
return block;
}
TOKEN init_declarator(SYMBOL s)
{
TOKEN decl = declarator(s);
TOKEN tok = peek_token();
if(tok == NULL)
{
return NULL;
}
TOKEN initial_value = NULL;
if(true == token_matches_operator(tok, ASSIGNMENT))
{
initial_value = NULL;//initializer();
}
return decl;
}
// Parse a concept definition.
//
// concept-declaration:
// 'concept' identifier '<' template-parameter-list '>' concept-definition
//
// TODO: I'm not sure that I like this syntax. Maybe we should make
// concepts look like any other template:
//
// template<typename T> concept C = ...
//
// Note that this would allow for non-template concepts as well:
//
// concept C = X && Y && Z;
//
// The benefit to doing this is that C would now be usable as a constraint
// in non-function templates.
//
// FIXME: Make this happen.
Decl&
Parser::concept_declaration()
{
Token tok = require(tk::concept_tok);
Name& n = declarator();
// Enter_template_parameter_scope pscope(cxt);
match(tk::lt_tok);
Decl_list ps = template_parameter_list();
match(tk::gt_tok);
// Point of declaration. Enter the associated context prior
// to defininging the concept.
Decl& con = on_concept_declaration(tok, n, ps);
// Enter_scope cscope(cxt, cxt.make_concept_scope(con));
concept_definition(con);
return con;
}
int direct_declarator(void) {
if( lookaheadT.type == ID ) {
match(ID);
} else if( lookaheadT.type == LPAREN ) {
match(LPAREN);
declarator();
match(RPAREN);
} else if( direct_declarator() ) {
if( lookaheadT.type == LBRACKET ) {
match(LBRACKET);
if( constant_expression() ) {
}
match(RBRACKET);
} else if( lookaheadT.type == LPAREN ) {
match(LPAREN);
if( parameter_type_list() ) {
} else if ( identifier_list() ) {
}
match(RPAREN);
}
}
}
/* FOLLOW(parameter-list) = { ')' }, peek to return empty list; even though K&R
* require at least specifier: (void)
* Set parameter-type-list = parameter-list, including the , ...
*/
static struct typetree *parameter_list(const struct typetree *base)
{
struct typetree *func = type_init(T_FUNCTION);
func->next = base;
while (peek().token != ')') {
const char *name = NULL;
struct typetree *type;
type = declaration_specifiers(NULL);
type = declarator(type, &name);
if (is_void(type)) {
if (nmembers(func)) {
error("Incomplete type in parameter list.");
}
break;
}
type_add_member(func, name, type);
if (peek().token != ',') {
break;
}
consume(',');
if (peek().token == ')') {
error("Unexpected trailing comma in parameter list.");
exit(1);
} else if (peek().token == DOTS) {
consume(DOTS);
assert(!is_vararg(func));
type_add_member(func, "...", NULL);
assert(is_vararg(func));
break;
}
}
return func;
}
static void declarator(node_t ** ty, struct token **id, int *params)
{
int follow[] = { ',', '=', IF, 0 };
cc_assert(ty && id);
if (token->id == '*') {
node_t *pty = ptr_decl();
prepend_type(ty, pty);
}
if (token->id == ID) {
*id = token;
expect(ID);
if (token->id == '[' || token->id == '(') {
node_t *faty = func_or_array(false, params);
prepend_type(ty, faty);
}
} else if (token->id == '(') {
node_t *type1 = *ty;
node_t *rtype = NULL;
expect('(');
declarator(&rtype, id, params);
match(')', follow);
if (token->id == '[' || token->id == '(') {
node_t *faty = func_or_array(false, params);
attach_type(&faty, type1);
attach_type(&rtype, faty);
} else {
attach_type(&rtype, type1);
}
*ty = rtype;
} else {
error("expect identifier or '('");
}
}
int direct_declarator(char* result)
{
char token[MAXTOKEN];
int type = -1;
int ret = 0;
ret -= try_tokens_until(&type, token, try_direct_declarator,
try_func_array, "Missing declarator's name");
if (type == '(') {
ret += declarator(result);
ret -= try_tokens_until(&type, token, try_right_paran, try_func_array,
"Missing ')' to close a declarator");
} else if (type == NAME) {
strcat(result, token);
strcat(result, ":");
}
while (true) {
type = gettoken(token);
if (type == '[') {
strcat(result, " array");
ret -= try_tokens_until(&type, token, try_array, try_func_array,
"Missing ']' to close an array");
if (type == NUMBER) {
strcat(result, "[");
strcat(result, token);
strcat(result, "]");
ret -= try_tokens_until(&type, token, try_right_bracket,
try_func_array,
"Missing ']' to close an array");
}
if (ret == 0) {
strcat(result, " of");
}
} else if (type == '(') {
strcat(result, " function");
bool has_param = false;
while (true) {
ret -= try_tokens_until(&type, token, try_func_param,
try_func_array,
"Missing ')' to close a function");
if (try_declaration(type)) {
if (!has_param) {
strcat(result, " with parameter [");
has_param = true;
}
unget_token();
ret += declaration(result);
ret -= try_tokens_until(&type, token, try_func_comma,
try_func_array_dcl,
"Missing ')' to close a function");
if (type == ',') {
strcat(result, ", ");
continue;
} else if (try_declaration(type)) {
continue;
} else {
// Fall through to break
}
}
break;
}
if (ret == 0) {
if (has_param) {
strcat(result, "]");
}
strcat(result, " returning");
}
} else {
// Don't try to do error recovery here. Simply ends a
// direct declarator and leaves the remaining tokens
// to the outside.
unget_token();
break;
}
}
return ret;
}
int parameter_declaration(void) {
declaration_specifiers();
if( declarator() ) {
} else if( abstract_declarator() ) {
}
}
