bitmap.c

#include <aria/slab.h>
#include <aria/bitmap.h>
#include <aria/string.h>
#include <aria/debug.h>

int bitmap_alloc(struct bitmap *bitmap, int *ret)
{
	if (bitmap == NULL || ret == NULL)
		RETURN_ERROR;
	if (bitmap->data == NULL)
		goto init;

	for (int i = 0; i < bitmap->size; i++) {
		if (BIT_TEST(bitmap->data, i) == 0) {
			BIT_SET(bitmap->data, i);
			*ret = i;
			return 0;
		}
	}

init:
	if (bitmap->data == NULL || bitmap->resizable) {
		if (!bitmap->size)
			bitmap->size = 2;
		else
			bitmap->size *= 2;

		bitmap->data = realloc(bitmap->data, DIV_ROUNDUP(bitmap->size, 8));
		if (bitmap->data == NULL)
			RETURN_ERROR;

		return bitmap_alloc(bitmap, ret);
	}

	return -1;
}

int bitmap_free(struct bitmap *bitmap, int index)
{
	if (bitmap == NULL)
		RETURN_ERROR;
	if (index > bitmap->size)
		return 0;

	BIT_CLEAR(bitmap->data, index);

	return 0;
}

int bitmap_dup(struct bitmap *bitmap, struct bitmap *dest)
{
	if (bitmap == NULL || dest == NULL)
		RETURN_ERROR;

	dest->size = bitmap->size;
	dest->resizable = bitmap->resizable;
	dest->data = alloc(DIV_ROUNDUP(bitmap->size, 8));
	if (dest->data == NULL)
		RETURN_ERROR;

	memcpy8(dest->data, bitmap->data, DIV_ROUNDUP(bitmap->size, 8));

	return 0;
}