Added lib folder for general stuff, introduced as target to Makefile

lib/darr.h

@@ -0,0 +1,39 @@
+/* Copyright (C) 2023 Aryadev Chavali
+
+ * You may distribute and modify this code under the terms of the
+ * GPLv2 license.  You should have received a copy of the GPLv2
+ * license with this file.  If not, please write to:
+ * aryadev@aryadevchavali.com.
+
+ * Created: 2023-10-15
+ * Author: Aryadev Chavali
+ * Description: Dynamically sized byte array
+ */
+
+#ifndef DARR_H
+#define DARR_H
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "./base.h"
+
+typedef struct
+{
+  byte *data;
+  size_t used, available;
+} darr_t;
+
+#define DARR_DEFAULT_SIZE 8
+#define DARR_REALLOC_MULT 1.5
+
+void darr_init(darr_t *, size_t);
+void darr_ensure_capacity(darr_t *, size_t);
+void darr_append_byte(darr_t *, byte);
+void darr_append_bytes(darr_t *, byte *, size_t);
+byte darr_at(darr_t *, size_t);
+
+void darr_write_file(darr_t *, FILE *);
+darr_t darr_read_file(FILE *);
+
+#endif