From b78d55926e729a670cb0b8225c22bb92b02f214b Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Wed, 3 Oct 2001 09:12:28 +0000 Subject: Cleanup brk/sbrk --- libc/sysdeps/linux/i386/brk.c | 60 +++++++++++++++++++++++++++---------------- 1 file changed, 38 insertions(+), 22 deletions(-) (limited to 'libc/sysdeps/linux/i386/brk.c') diff --git a/libc/sysdeps/linux/i386/brk.c b/libc/sysdeps/linux/i386/brk.c index 9e06d0acc..eca0e8326 100644 --- a/libc/sysdeps/linux/i386/brk.c +++ b/libc/sysdeps/linux/i386/brk.c @@ -1,32 +1,48 @@ -/* From libc-5.3.12 */ +/* brk system call for Linux/i386. + 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 #include #include -#include -extern void * ___brk_addr; -extern int __init_brk (); +/* This must be initialized data because commons can't have aliases. */ +void *___brk_addr = 0; -int brk(void * end_data_seg) +int brk (void *addr) { - if (__init_brk () == 0) + void *__unbounded newbrk, *__unbounded scratch; + + asm ("movl %%ebx, %1\n" /* Save %ebx in scratch register. */ + "movl %3, %%ebx\n" /* Put ADDR in %ebx to be syscall arg. */ + "int $0x80 # %2\n" /* Perform the system call. */ + "movl %1, %%ebx\n" /* Restore %ebx from scratch register. */ + : "=a" (newbrk), "=r" (scratch) + : "0" (__NR_brk), "g" (__ptrvalue (addr))); + + ___brk_addr = newbrk; + + if (newbrk < addr) { -#if defined(__PIC__) || defined (__pic__) - __asm__ volatile ("pushl %%ebx\n\t" - "movl %%ecx,%%ebx\n\t" - "int $0x80\n\t" - "popl %%ebx" - :"=a" (___brk_addr) - :"0" (__NR_brk),"c" (end_data_seg)); -#else - __asm__ volatile ("int $0x80" - :"=a" (___brk_addr) - :"0" (__NR_brk),"b" (end_data_seg)); -#endif - if (___brk_addr == end_data_seg) - return 0; - __set_errno(ENOMEM); + __set_errno (ENOMEM); + return -1; } - return -1; + + return 0; } -- cgit v1.2.3