init basic

ccompiler/frontend/parser/parser.c

@@ -0,0 +1,67 @@
+#include "parser.h"
+#include "type.h"
+#include "ast/ast.h"
+
+int poptok(struct Parser* parser) {
+    if (parser->size == 0) {
+        return -1;
+    }
+    int idx = parser->cur_idx;
+    parser->cur_idx = (idx + 1) % PARSER_MAX_TOKEN_QUEUE;
+    parser->size--;
+    return 0;
+}
+
+void flushpeektok(struct Parser* parser) {
+    parser->peek_idx = parser->cur_idx;
+}
+
+struct Token* peektok(struct Parser* parser) {
+    int idx = parser->peek_idx;
+    idx = (idx + 1) % PARSER_MAX_TOKEN_QUEUE;
+    if (parser->size >= PARSER_MAX_TOKEN_QUEUE) {
+        warn("peek maybe too deep");
+    }
+    if (parser->peek_idx == parser->end_idx) {
+        if (parser->size == PARSER_MAX_TOKEN_QUEUE) {
+            // FIXME
+            error("buffer overflow");
+        }
+        get_valid_token(parser->lexer, &(parser->TokenBuffer[idx]));
+        parser->size++;
+        parser->end_idx = idx;
+    }
+    
+    parser->peek_idx = idx;
+    return &(parser->TokenBuffer[idx]);
+}
+
+enum TokenType peektoktype(struct Parser* parser) {
+    return peektok(parser)->type;
+}
+
+void expecttok(struct Parser* parser, enum TokenType type) {
+    struct Token* tok = peektok(parser);
+    if (tok->type != type) {
+        error("expected tok: %s, got %s", get_token_name(type), get_token_name(tok->type));
+    } else {
+        poptok(parser);
+    }
+}
+
+void init_parser(struct Parser* parser, struct Lexer* lexer, struct SymbolTable* symtab) {
+    parser->cur_node = NULL;
+    parser->root = NULL;
+
+    parser->cur_idx = 0;
+    parser->peek_idx = 0;
+    parser->end_idx = 0;
+    parser->size = 0;
+    parser->lexer = lexer;
+    parser->symtab = symtab;
+    // TODO
+}
+
+void run_parser(struct Parser* parser) {
+    parse_prog(parser);
+}