/*
 * Copyright (c) 2010, Stefan Lankes, RWTH Aachen University
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *    * Neither the name of the University nor the names of its contributors
 *      may be used to endorse or promote products derived from this
 *      software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * @author Stefan Lankes
 * @file include/eduos/stdlib.h
 * @brief Kernel space malloc and free functions and conversion functions
 *
 * This file contains some memory alloc and free calls for the kernel
 * and conversion functions.
 */

#ifndef __STDLIB_H__
#define __STDLIB_H__

#include <eduos/config.h>
#include <asm/stddef.h>

#ifdef __cplusplus
extern "C" {
#endif

/** @brief General page allocator function
 *
 * This function allocates and maps whole pages.
 * To avoid fragmentation you should use kmalloc() and kfree()!
 *
 * @param sz Desired size of the new memory
 * @param flags Flags to for map_region(), vma_add()
 *
 * @return Pointer to the new memory range
 */
void* palloc(size_t sz, uint32_t flags);

/** @brief Free general kernel memory
 *
 * The pmalloc() doesn't track how much memory was allocated for which pointer,
 * so you have to specify how much memory shall be freed.
 *
 * @param sz The size which should freed
 */
void pfree(void* addr, size_t sz);

/** @brief The memory allocator function
 *
 * This allocator uses a buddy system to manage free memory.
 *
 * @return Pointer to the new memory range
 */
void* kmalloc(size_t sz);

/** @brief The memory free function
 *
 * Releases memory allocated by malloc()
 *
 * @param addr The address to the memory block allocated by malloc()
 */
void kfree(void* addr);

/** @brief Create a new stack for a new task
 *
 * @return start address of the new stack
 */
void* create_stack(tid_t id);

#ifdef __cplusplus
}
#endif

#endif