calculator/include/heap.h

/**
 * @file heap.h
 * A basic memory manager
 *
 * Copyright (C) 2018 Clyne Sullivan
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#ifndef HEAP_H_
#define HEAP_H_

#include <stdint.h>

typedef struct {
	uint32_t size;
	void *next;
} __attribute__ ((packed)) alloc_t;

/**
 * Initializes memory management of the given heap.
 * No overflow stuff is done, so...
 * @param buf the heap to use for allocations
 */
void heap_init(void *buf);

/**
 * Allocates a chunk of memory.
 * @param size how many bytes to claim
 * @return pointer to the allocated buffer
 */
void *malloc(uint32_t size);

/**
 * Allocates and zeros a chunk of memory.
 * @param count how many of whatever to allocate
 * @param size byte count of each whatever
 * @return pointer to the allocated buffer
 */
void *calloc(uint32_t count, uint32_t size);

/**
 * Frees the buffer allocated through malloc/calloc.
 * Please don't double-free.
 * @param the buffer to release
 */
void free(void *buf);

#endif // HEAP_H_