/* brk system call for Linux/Nios2.   Copyright (C) 1995, 1996, 2000 Free Software Foundation, Inc.   This file is part of the GNU C Library.   The GNU C Library is free software; you can redistribute it and/or   modify it under the terms of the GNU Lesser General Public   License as published by the Free Software Foundation; either   version 2.1 of the License, or (at your option) any later version.   The GNU C Library 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   Lesser General Public License for more details.   You should have received a copy of the GNU Lesser General Public   License along with the GNU C Library; if not, write to the Free   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA   02111-1307 USA.  */#include <unistd.h>#include <sys/syscall.h>#include <errno.h>/* This must be initialized data because commons can't have aliases.  */void *__curbrk = 0;int brk (void *addr){    void *newbrk;    register int r2 asm("r2") = TRAP_ID_SYSCALL;    register int r3 asm("r3") = __NR_brk;    register void *r4 asm("r4") = addr;    asm volatile ("trap\n\t" : "=r"(newbrk) : "0"(r2), "r"(r3), "r"(r4));    __curbrk = newbrk;    if (newbrk < addr) {      __set_errno (ENOMEM);      return -1;    }    return 0;}