feat: support parsing function pointer declaration

2 files changed, 34 insertions, 6 deletions

diff --git a/src/parse.c b/src/parse.c
index 14fd7d2..c742f88 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -912,6 +912,7 @@ static AstNode* parse_declarator_or_abstract_declarator_opt(Parser* p, Type* ty)
                         token_stringify(tok));
         }
         decl = parse_declarator_or_abstract_declarator_opt(p, ty);
+        expect(p, TokenKind_paren_r);
     } else {
         decl = ast_new(AstNodeKind_declarator);
         decl->ty = ty;
@@ -1029,26 +1030,41 @@ static Type* parse_function_declarator_suffix(Parser* p, Type* ty) {
     return type_new_func(ty, params);
 }
 
+static AstNode* parse_declarator(Parser* p, Type* ty);
+
 // direct-declarator:
 //     identifier TODO attribute-specifier-sequence?
-//     TODO '(' declarator ')'
+//     '(' declarator ')'
 //     array-declarator TODO attribute-specifier-sequence?
 //     function-declarator TODO attribute-specifier-sequence?
 static AstNode* parse_direct_declarator(Parser* p, Type* ty) {
-    const Token* name = parse_ident(p);
+    AstNode* decl;
+    if (peek_token(p)->kind == TokenKind_ident) {
+        decl = ast_new(AstNodeKind_declarator);
+        decl->name = parse_ident(p)->value.string;
+        decl->ty = ty;
+    } else if (peek_token(p)->kind == TokenKind_paren_l && !is_type_token(p, peek_token2(p))) {
+        next_token(p);
+        decl = parse_declarator(p, ty);
+        expect(p, TokenKind_paren_r);
+    } else {
+        decl = ast_new(AstNodeKind_declarator);
+        decl->ty = ty;
+    }
+
     while (1) {
         if (peek_token(p)->kind == TokenKind_bracket_l) {
-            ty = parse_array_declarator_suffix(p, ty);
+            decl->ty = parse_array_declarator_suffix(p, decl->ty);
         } else if (peek_token(p)->kind == TokenKind_paren_l) {
-            ty = parse_function_declarator_suffix(p, ty);
+            decl->ty = parse_function_declarator_suffix(p, decl->ty);
         } else {
             break;
         }
     }
 
     AstNode* ret = ast_new(AstNodeKind_declarator);
-    ret->name = name->value.string;
-    ret->ty = ty;
+    ret->name = decl->name;
+    ret->ty = decl->ty;
     return ret;
 }
 
diff --git a/tests/test_function_pointers.sh b/tests/test_function_pointers.sh
new file mode 100644
index 0000000..c97a087
--- /dev/null
+++ b/tests/test_function_pointers.sh
@@ -0,0 +1,12 @@
+cat <<'EOF' > expected
+EOF
+
+test_diff <<'EOF'
+int* f(int a);
+int (*f)(int a);
+
+extern int atexit (void (*) (void));
+extern int atexit (void (*fn) (void));
+
+int main() {}
+EOF