a lot of stuff.

1 files changed, 150 insertions, 0 deletions

diff --git a/src/lexer.c b/src/lexer.c
new file mode 100644
index 0000000..02417a1
--- /dev/null
+++ b/src/lexer.c
@@ -0,0 +1,150 @@
+#include "./include/lexer.h"
+#include "./include/macros.h"
+#include "./include/token.h"
+
+#include <ctype.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+void lexer_reset(lexer_t *lexer, char *source) {
+  lexer->source = source;
+  lexer->c = source[0];
+  lexer->i = 0;
+  lexer->row = 1;
+  lexer->col = 1;
+  lexer->finished = false;
+}
+
+lexer_t *init_lexer(char *source) {
+  lexer_t *l = (lexer_t *)malloc(sizeof(lexer_t));
+  if (l == NULL)
+    die("malloc on lexer");
+  lexer_reset(l, source);
+  return l;
+}
+
+void lexer_move(lexer_t *lexer) {
+  if (lexer->c != '\0') {
+    lexer->i++;
+    lexer->c = lexer->source[lexer->i];
+    if (lexer->c == '\n') {
+      lexer->row++;
+      lexer->col = 0;
+    }
+  } else
+    lexer->finished = true;
+}
+
+void lexer_ignore_whitespace(lexer_t *lexer) {
+  while (isspace(lexer->c))
+    lexer_move(lexer);
+}
+
+void lexer_skip_comment(lexer_t *lexer) {
+  while (lexer->c != '\n' && lexer->c != '\0')
+    lexer_move(lexer);
+}
+
+static bool is_valid_id_char(char c) {
+  if (c == '(' || c == ')' || isdigit(c) || c == '"' || c == '\'' || c == '#' ||
+      c == '.')
+    return false;
+  return true;
+}
+
+static char *char_to_string(char c) {
+  char *s = (char *)malloc(2 * sizeof(char));
+  s[0] = c;
+  s[1] = '\0';
+  return s;
+}
+
+token_t *lexer_collect_bool(lexer_t *lexer) {
+  lexer_move(lexer);
+  if (lexer->c == 't')
+    return init_token(TOKEN_BOOL, "T", lexer->row, lexer->col);
+  else if (lexer->c == 'f')
+    return init_token(TOKEN_BOOL, "F", lexer->row, lexer->col);
+  else
+    return NULL;
+}
+
+token_t *lexer_collect_id(lexer_t *lexer) {
+  char *ret = (char *)malloc(1);
+  ret[0] = '\0';
+
+  while (is_valid_id_char(lexer->c)) {
+    ret = realloc(ret, (strlen(ret) + 2));
+    strcat(ret, char_to_string(lexer->c));
+    lexer_move(lexer);
+  }
+  return init_token(TOKEN_ID, ret, lexer->row, lexer->col);
+}
+
+token_t *lexer_collect_num(lexer_t *lexer) {
+  char *ret = (char *)malloc(1);
+  ret[0] = '\0';
+  bool is_float = false;
+  while (isdigit(lexer->c) || (lexer->c == '.' && !is_float)) {
+    if (lexer->c == '.')
+      is_float = true;
+    ret = realloc(ret, (strlen(ret) + 2));
+    strcat(ret, char_to_string(lexer->c));
+    lexer_move(lexer);
+  }
+  if (is_float)
+    return init_token(TOKEN_FLOAT, ret, lexer->row, lexer->col);
+  return init_token(TOKEN_INT, ret, lexer->row, lexer->col);
+}
+
+token_t *lexer_collect_string(lexer_t *lexer) {
+  char *ret = (char *)malloc(1);
+  ret[0] = '\0';
+  lexer_move(lexer);
+  while (lexer->c != '"') {
+    ret = realloc(ret, (strlen(ret) + 2));
+    strcat(ret, char_to_string(lexer->c));
+    lexer_move(lexer);
+  }
+  lexer_move(lexer);
+  return init_token(TOKEN_STRING, ret, lexer->row, lexer->col);
+}
+
+static token_t *lexer_move_with(lexer_t *lexer, token_t *token) {
+  lexer_move(lexer);
+  return token;
+}
+
+token_t *lexer_collect_next(lexer_t *lexer) {
+  if (lexer->c == '\0') {
+    lexer->finished = true;
+    return NULL;
+  }
+  if (isspace(lexer->c))
+    lexer_ignore_whitespace(lexer);
+
+  if (isdigit(lexer->c))
+    return lexer_collect_num(lexer);
+  else if (is_valid_id_char(lexer->c))
+    return lexer_collect_id(lexer);
+  else if (lexer->c == '"')
+    return lexer_collect_string(lexer);
+  else if (lexer->c == '#')
+    return lexer_collect_bool(lexer);
+  else if (lexer->c == '(')
+    return lexer_move_with(
+        lexer, init_token(TOKEN_LPAREN, "(", lexer->row, lexer->col));
+  else if (lexer->c == ')')
+    return lexer_move_with(
+        lexer, init_token(TOKEN_RPAREN, ")", lexer->row, lexer->col));
+  else if (lexer->c == '\'')
+    return lexer_move_with(
+        lexer, init_token(TOKEN_QUOTE, "'", lexer->row, lexer->col));
+  else if (lexer->c == '.')
+    return lexer_move_with(
+        lexer, init_token(TOKEN_PERIOD, ".", lexer->row, lexer->col));
+  else
+    return NULL;
+}