From 1d7f9676ec3e0584d534d4a67040ca148d87643d Mon Sep 17 00:00:00 2001
From: laentropia <aadrian887mh@gmail.com>
Date: Wed, 15 Apr 2026 10:01:27 -0600
Subject: [PATCH] addition: resize and reserve, not tested

---
 include/arraylist.h |  1 +
 src/arraylist.c     | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/include/arraylist.h b/include/arraylist.h
index b048ce3..273c972 100644
--- a/include/arraylist.h
+++ b/include/arraylist.h
@@ -19,6 +19,7 @@ typedef enum {
     ARRLIST_EMPTY,
     ARRLIST_NULL_ARG,
     ARRLIST_INVALID_ELEM_SIZE,
+    ARRLIST_INVALID_CAPACITY,
 } ArrayListErr;
 
 ArrayList *arraylist_init(size_t capacity, size_t elem_size);
diff --git a/src/arraylist.c b/src/arraylist.c
index 1392edb..a662f50 100644
--- a/src/arraylist.c
+++ b/src/arraylist.c
@@ -319,3 +319,44 @@ ArrayListErr arraylist_set(ArrayList *arr, size_t index, void *data) {
 
     return ARRLIST_OK;
 }
+
+ArrayListErr arraylist_resize(ArrayList *arr, size_t new_capacity) {
+    if (arr == NULL) {
+        return ARRLIST_NULL_ARG;
+    }
+
+    if (new_capacity < 1) {
+        return ARRLIST_INVALID_CAPACITY;
+    }
+
+    uint8_t *tmp = realloc(arr->buffer, new_capacity * arr->elem_size);
+    if (tmp == NULL) {
+        return ARRLIST_BAD_ALLOC;
+    }
+
+    arr->buffer = tmp;
+    arr->capacity = new_capacity;
+    return ARRLIST_OK;
+}
+
+ArrayListErr arraylist_reserve(ArrayList *arr, size_t size_to_reserve) {
+    if (arr == NULL) {
+        return ARRLIST_NULL_ARG;
+    }
+
+    if (size_to_reserve < 1) {
+        return ARRLIST_INVALID_CAPACITY;
+    }
+
+    uint8_t *tmp = realloc(
+        arr->buffer,
+        (arr->capacity + size_to_reserve) * arr->elem_size);
+
+    if (tmp == NULL) {
+        return ARRLIST_BAD_ALLOC;
+    }
+
+    arr->buffer = tmp;
+    arr->capacity += size_to_reserve;
+    return ARRLIST_OK;
+}