Add dynamic array functionality

include/htd/data_structure/dynamic_array.h

@@ -19,4 +19,10 @@ void dynarr_push(DynamicArray* arr, void* data);
 
 void dynarr_free(DynamicArray* arr);
 
+void* dynarr_last(DynamicArray* arr);
+
+void dynarr_remove(DynamicArray* arr, usize idx);
+
+void* dynarr_pop(DynamicArray* arr);
+
 #endif // DYNAMIC_ARRAY_H

src/data_structure/dynamic_array.c

@@ -18,6 +18,16 @@ void* dynarr_at(DynamicArray* arr, usize idx) {
     return &((u8*)arr->data)[arr->data_size * idx];
 }
 
+void* dynarr_last(DynamicArray* arr) {
+    return &((u8*)arr->data)[arr->data_size * (arr->len - 1)];
+}
+
+void dynarr_remove(DynamicArray* arr, usize idx) {
+    void* data = dynarr_at(arr, idx);
+    memmove(data, &((u8*)arr->data)[arr->data_size * (idx + 1)], (arr->len - idx - 1) * arr->data_size);
+    arr->len--;
+}
+
 void dynarr_push(DynamicArray* arr, void* data) {
     if (arr->len >= arr->capacity) {
         arr->capacity *= GROWTH_FACTOR;
@@ -28,6 +38,15 @@ void dynarr_push(DynamicArray* arr, void* data) {
     arr->len++;
 }
 
+void* dynarr_pop(DynamicArray* arr) {
+    if (arr->len == 0) {
+        return NULL;
+    }
+    
+    arr->len--;
+    return dynarr_last(arr);
+}
+
 void dynarr_free(DynamicArray* arr) {
     free(arr->data);
     arr->data = NULL;

tests/test_dynamic_array.c

@@ -16,5 +16,17 @@ int main() {
         assert(*(i32*)dynarr_at(&i32_array, i) == i);
     }
 
+    for (i32 i = 0; i < 100; i++) {
+        dynarr_pop(&i32_array);
+        assert(i32_array.len == 99 - i);
+    }
+
+    for (i32 i = 0; i < 100; i++) {
+        dynarr_push(&i32_array, &i);
+    }
+    dynarr_remove(&i32_array, 50);
+    assert(i32_array.len == 99);
+    assert(*(i32*)dynarr_at(&i32_array, 50) == 51);
+
     dynarr_free(&i32_array);
 }