path: root/src/malloc/realloc.c

/**
 * slibc — Yet another C library
 * Copyright © 2015, 2016  Mattias Andrée (maandree@member.fsf.org)
 * 
 * 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 <http://www.gnu.org/licenses/>.
 */
#include <stdlib.h>
#include <slibc-alloc.h>



/**
 * Variant of `malloc` that extends, or shrinks, an existing allocation,
 * if beneficial and possible, or creates a new allocation with the new
 * size, copies the data, and frees the old allocation. The returned
 * pointer has an alignment usable for any compiler-independent intrinsic
 * data type, if a new pointer is returned.
 * 
 * On error, `ptr` is not freed.
 * 
 * @etymology  Memory (realloc)ation.
 * 
 * @param   ptr   Pointer to the beginning of the old memory allocation.
 *                The process may crash if it does not point to the
 *                beginning of a memory allocation on the heap.
 *                However, if it is `NULL`, this function will behave
 *                like `malloc`.
 * @param   size  The new allocation size. If zero, this function will
 *                behave like `free`, and will return `NULL`.
 * @return        Pointer to the beginning of the new allocation.
 *                If `size` is zero, `NULL` is returned. On error `NULL`
 *                is returned and `errno` is set to indicate the error.
 * 
 * @throws  ENOMEM  The process cannot allocate more memory.
 * 
 * @since  Always.
 */
void* realloc(void* ptr, size_t size)
{
  return fast_realloc(ptr, size);
}