#ifndef MEMBLOCK_H_
#define MEMBLOCK_H_

#include <stddef.h>
#include <limits.h>
#include <stdint.h>

#define MEMBLOCK_INIT_MEMORY_REGION_COUNT 128
#define MEMBLOCK_INIT_RESERVED_REGION_COUNT 128

#define __for_each_mem_range(i, type_a, type_b, p_start, p_end) \
	for ((i)->idx = 0, __next_memory_region(i, type_a, type_b, p_start, p_end); \
			(i)->idx != ULLONG_MAX; \
			__next_memory_region(i, type_a, type_b, p_start, p_end))

#define for_each_mem_range(i, p_start, p_end) \
	__for_each_mem_range(i, &memblock.memory, NULL, p_start, p_end)

#define for_each_reserved_mem_range(i, p_start, p_end) \
	__for_each_mem_range(i, &memblock.reserved, NULL, p_start, p_end)

#define for_each_free_mem_range(i, p_start, p_end) \
	__for_each_mem_range(i, &memblock.memory, &memblock.reserved, p_start, p_end)

typedef uint64_t memblock_index_t;

typedef struct memblock_region {
	/* the address of the first byte that makes up the region */
	uintptr_t base;
	/* the address of the last byte that makes up the region */
	size_t limit;
} memblock_region_t;

typedef struct memblock_type {
	struct memblock_region *regions;
	unsigned int count;
	unsigned int max;
	const char *name;
} memblock_type_t;

typedef struct memblock {
	struct memblock_type memory;
	struct memblock_type reserved;
} memblock_t;

typedef struct memblock_iter {
	memblock_index_t idx;
	uintptr_t base;
	size_t limit;
} memblock_iter_t;

extern memblock_t memblock;

extern int __next_mem_range(memblock_iter_t *it);

extern int memblock_add(uintptr_t base, size_t size);
extern int memblock_reserve(uintptr_t base, size_t size);

extern uintptr_t memblock_alloc(size_t size);

extern void __next_memory_region(memblock_iter_t *it, \
		memblock_type_t *type_a, memblock_type_t *type_b,
		uintptr_t start, uintptr_t end);

#endif