dynarray.h

#pragma once
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <assert.h>

#define DynArray(type)     \
	struct {               \
		type *arr;         \
		uint64_t size;     \
		uint64_t capacity; \
		Arena *alloc;      \
	}

#define elem_size(dyn) sizeof(*((dyn)->arr))
#define dyn_init(allo, dyn, start_capacity)                                        \
	do {                                                                           \
		(dyn)->capacity = (start_capacity);                                        \
		(dyn)->size = 0;                                                           \
		(dyn)->alloc = (allo);                                                     \
		(dyn)->arr = arena_alloc((dyn)->alloc, elem_size(dyn) * (start_capacity)); \
	} while (0)

#define dyn_resize(dyn, new_size)                                                                                            \
	do {                                                                                                                     \
		(dyn)->arr = arena_realloc((dyn)->alloc, (dyn)->arr, elem_size(dyn) * (dyn)->capacity, elem_size(dyn) * (new_size)); \
		(dyn)->capacity = (new_size);                                                                                        \
	} while (0)

#define dyn_append(dyn, elem)                        \
	do {                                             \
		if ((dyn)->size + 1 > (dyn)->capacity) {     \
			dyn_resize((dyn), (dyn)->capacity * 2);  \
		}                                            \
		(dyn)->arr[(dyn)->size] = elem;              \
		(dyn)->size += 1;                            \
	} while (0)

#define dyn_get(dyn, idx) (dyn)->arr[(idx)]

#define dyn_assign(dyn1, dyn2)               \
	do {                                     \
		(dyn1)->arr      = (dyn2)->arr;      \
		(dyn1)->size     = (dyn2)->size;     \
		(dyn1)->capacity = (dyn2)->capacity; \
	} while (0)