#include "allocator.h"

#include <errno.h>
#include <stdlib.h>

static void *stdlib_heap_alloc(const struct allocator *allocator,
	size_t size, int *rc);
static void *stdlib_heap_realloc(const struct allocator *allocator,
	void *p, size_t size, int *rc);
static int stdlib_heap_free(const struct allocator *allocator, void *p);

static void *stdlib_strict_heap_alloc(const struct allocator *allocator,
	size_t size, int *rc);
static void *stdlib_strict_heap_realloc(const struct allocator *allocator,
	void *p, size_t size, int *rc);
static int stdlib_strict_heap_free(const struct allocator *allocator, void *p);

const struct allocator stdlib_heap_allocator = {
	.alloc = stdlib_heap_alloc,
	.realloc = stdlib_heap_realloc,
	.free = stdlib_heap_free
};

const struct allocator stdlib_strict_heap_allocator = {
	.alloc = stdlib_strict_heap_alloc,
	.realloc = stdlib_strict_heap_realloc,
	.free = stdlib_strict_heap_free
};

void *
stdlib_heap_alloc(const struct allocator *allocator, size_t size, int *rc)
{
	void *p;

	p = malloc(size);
	if (rc && !p) *rc = errno;

	return p;
}

void *
stdlib_heap_realloc(const struct allocator *allocator,
	void *p, size_t size, int *rc)
{
	void *np;

	np = realloc(p, size);
	if (rc && !np) *rc = errno;

	return np;
}

int
stdlib_heap_free(const struct allocator *allocator, void *p)
{
	free(p);

	return 0;
}

void *
stdlib_strict_heap_alloc(const struct allocator *allocator,
	size_t size, int *rc)
{
	void *p;

	p = malloc(size);
	if (!p) abort();

	return p;
}

void *
stdlib_strict_heap_realloc(const struct allocator *allocator,
	void *p, size_t size, int *rc)
{
	void *np;

	np = realloc(p, size);
	if (!np) abort();

	return np;
}

int
stdlib_strict_heap_free(const struct allocator *allocator, void *p)
{
	free(p);

	return 0;
}

void *
strict_allocator_alloc(const struct allocator *allocator, size_t size, int *rc)
{
	const struct strict_allocator *strict_allocator;
	void *p;

	strict_allocator = ((void *) allocator)
		- offsetof(struct strict_allocator, allocator);

	p = strict_allocator->allocator_ul->alloc(
		strict_allocator->allocator_ul, size, rc);
	if (!p) abort();

	return p;
}

void *
strict_allocator_realloc(const struct allocator *allocator,
	void *p, size_t size, int *rc)
{
	const struct strict_allocator *strict_allocator;
	void *np;

	strict_allocator = ((void *) allocator)
		- offsetof(struct strict_allocator, allocator);

	np = strict_allocator->allocator_ul->realloc(
		strict_allocator->allocator_ul, p, size, rc);
	if (!np) abort();

	return np;
}

int
strict_allocator_free(const struct allocator *allocator, void *p)
{
	const struct strict_allocator *strict_allocator;
	int rc;

	strict_allocator = ((void *) allocator)
		- offsetof(struct strict_allocator, allocator);

	rc = strict_allocator->allocator_ul->free(
		strict_allocator->allocator_ul, p);
	if (rc) abort();

	return 0;
}

void
strict_allocator_init(struct strict_allocator *strict_allocator,
	const struct allocator *allocator_ul)
{
	strict_allocator->allocator_ul = allocator_ul;
	strict_allocator->allocator.alloc = strict_allocator_alloc;
	strict_allocator->allocator.realloc = strict_allocator_realloc;
	strict_allocator->allocator.free = strict_allocator_free;
}