/**************************************************************************** * mm/kmm_heap/kmm_sbrk.c * * Copyright (C) 2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * 3. Neither the name NuttX 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 * COPYRIGHT OWNER 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. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #if defined(CONFIG_BUILD_KERNEL) && defined(__KERNEL__) /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: kmm_sbrk * * Description: * The sbrk() function is used to change the amount of space allocated * for the calling process. The change is made by resetting the process's * break value and allocating the appropriate amount of space. The amount * of allocated space increases as the break value increases. * * The sbrk() function adds 'incr' bytes to the break value and changes * the allocated space accordingly. If incr is negative, the amount of * allocated space is decreased by incr bytes. The current value of the * program break is returned by sbrk(0). * * Input Parameters: * incr - Specifies the number of bytes to add or to remove from the * space allocated for the process. * * Returned Value: * Upon successful completion, sbrk() returns the prior break value. * Otherwise, it returns (void *)-1 and sets errno to indicate the * error: * * ENOMEM - The requested change would allocate more space than * allowed under system limits. * EAGAIN - The total amount of system memory available for allocation * to this process is temporarily insufficient. This may occur even * though the space requested was less than the maximum data segment * size. * ****************************************************************************/ FAR void *kmm_sbrk(intptr_t incr) { return mm_sbrk(&g_kmmheap, incr, UINTPTR_MAX); } #endif /* CONFIG_BUILD_KERNEL && __KERNEL__ */