122 lines
2.5 KiB
C
122 lines
2.5 KiB
C
#include "scanner.h"
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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const char* source_code;
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//Start and Current hold the offsets that index into the string source_code.
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int start; //Points to the first character in the lexeme being scanned.
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int current; //points to the character currently being considered.
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int length;
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int line = 1;
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char Advance(void);
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int IsAtend(void);
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void ScanToken(void);
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TokenList* CreateList(void);
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TokenList* ScanTokens(const char* source) {
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if (!source) return NULL;
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source_code = source;
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length = strlen(source);
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if (length == 0) return NULL;
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while(!IsAtend()) {
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start = current;
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ScanToken();
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}
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//Add EOF token and return list once that's set up.
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}
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TokenList* CreateList() {
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TokenList* list = calloc(1, sizeof(TokenList));
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if (!list) {
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fprintf(stderr, "Failed to calloc TokenList.\n");
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return NULL;
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}
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list->tokens = calloc(DEFAULT_TOKENLIST_SIZE, sizeof(Token*));
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if (!list->tokens) {
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free(list);
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fprintf(stderr, "Failed to calloc tokens.\n");
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return NULL;
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}
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list->capacity = DEFAULT_TOKENLIST_SIZE;
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list->size = 0;
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return list;
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}
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void DestroyTokenList(TokenList* list) {
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if (!list) return;
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for(int i = 0; i < list->size; i++) {
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free(list->tokens[i]->lexeme);
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free(list->tokens[i]);
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}
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free(list->tokens);
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free(list);
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}
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int AddTokenToList(TokenType type, char* lexeme, TokenList* tokens) {
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if (!tokens) return 0;
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Token* token = calloc(1, sizeof(Token));
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if (!token) {
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fprintf(stderr, "Failed to calloc memory for new Token.\n");
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return 0;
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}
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token->lexeme = lexeme;
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token->type = type;
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if ((tokens->size + 1) > tokens->capacity) {
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void* new_ptr = realloc(tokens->tokens, sizeof(Token*) * tokens->capacity * 2);//calloc(tokens->capacity * 2, sizeof(Token*));
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if (!new_ptr) {
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fprintf(stderr, "Failed to realloc TokenList to size %d.\n", tokens->capacity * 2);
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return 0;
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}
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tokens->tokens = new_ptr;
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tokens->capacity = tokens->capacity * 2;
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}
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tokens->tokens[tokens->size] = token;
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tokens->size++;
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return 1;
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}
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void ScanToken() {
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char c = Advance();
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switch (c) {
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case '(':
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case ')':
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case '{':
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case '}':
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case ',':
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case '.':
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case '-':
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case '+':
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case ';':
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case '*':
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break;
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}
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}
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int IsAtEnd() {
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return current >= length;
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}
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char Advance() {
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return source_code[current++];
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} |