From c7e2eb8c34f9514503ced1d98d8a1cb13be793af Mon Sep 17 00:00:00 2001
From: Kyler <kylerolsen17@gmail.com>
Date: Sun, 2 Nov 2025 22:13:19 -0700
Subject: [PATCH] Started lexer

---
 SLS_C/src/lexer.c | 73 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 SLS_C/src/lexer.c

diff --git a/SLS_C/src/lexer.c b/SLS_C/src/lexer.c
new file mode 100644
index 0000000..f917f1b
--- /dev/null
+++ b/SLS_C/src/lexer.c
@@ -0,0 +1,73 @@
+// Kyler Olsen
+// YREA SLS
+// Lexer
+// November 2025
+
+#include <ctype.h>
+#include <string.h>
+#include <stdint.h>
+
+#include "sls/sls_errors.h"
+#include "sls/lexer.h"
+
+void init_lexer(LexerInfo *lexer_info, const char *filename, const char *source_code) {
+    lexer_info->filename = filename;
+    lexer_info->source_code = source_code;
+    lexer_info->pos = 0;
+    lexer_info->column = 1;
+    lexer_info->line = 1;
+}
+
+static FileInfo get_file_info(LexerInfo *lexer_info, size_t start, size_t start_line) {
+    return (FileInfo){
+        .filename = lexer_info->filename,
+        .line = lexer_info->line,
+        .column = lexer_info->column,
+        .length = lexer_info->pos - start,
+        .lines = lexer_info->line - start_line
+    };
+}
+
+static char peek(LexerInfo *lexer_info) {
+    return lexer_info->source_code[lexer_info->pos];
+}
+
+static char far_peek(LexerInfo *lexer_info, size_t index) {
+    return lexer_info->source_code[lexer_info->pos + index];
+}
+
+static void advance(LexerInfo *lexer_info) {
+    if (lexer_info->source_code[lexer_info->pos] == '\n') {
+        lexer_info->line++;
+        lexer_info->column = 1;
+    } else {
+        lexer_info->column++;
+    }
+    lexer_info->source_code[lexer_info->pos++];
+}
+
+static LexerResult lexer_result(LexerInfo *lexer_info, Token token, size_t start, size_t start_line) {
+    LexerTokenResult *result = (LexerTokenResult *)malloc(sizeof(LexerTokenResult));
+    if (result == NULL)
+        return (LexerResult){SLS_ERROR, .error = (SlsError){"Failed to allocate memory.", 1}};
+    result->type = SLS_RESULT;
+    result->result = token;
+    result->file_info = get_file_info(lexer_info, start, start_line);
+    result->next = NULL;
+    return (LexerResult){SLS_RESULT, .result = result};
+}
+
+static LexerResult lexer_error(LexerInfo *lexer, const char* message, size_t start, size_t start_line) {
+    LexerTokenResult *result = (LexerTokenResult *)malloc(sizeof(LexerTokenResult));
+    if (result == NULL)
+        return (LexerResult){SLS_ERROR, .error = (SlsError){"Failed to allocate memory.", 1}};
+    result->type = SLS_ERROR;
+    result->error.message = message;
+    result->error.code = 1;
+    result->file_info = get_file_info(lexer, start, start_line);
+    result->next = NULL;
+    return (LexerResult){SLS_RESULT, .result = result};
+}
+
+LexerResult lexical_analysis(LexerInfo *lexer_info);
+void clean_token_result(LexerTokenResult *head);