diff options
Diffstat (limited to 'lib/libc/arm/sys/brk.S')
-rw-r--r-- | lib/libc/arm/sys/brk.S | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/lib/libc/arm/sys/brk.S b/lib/libc/arm/sys/brk.S new file mode 100644 index 0000000..5fdf90c --- /dev/null +++ b/lib/libc/arm/sys/brk.S @@ -0,0 +1,100 @@ +/* $NetBSD: brk.S,v 1.6 2003/08/07 16:42:04 agc Exp $ */ + +/*- + * Copyright (c) 1990 The Regents of the University of California. + * All rights reserved. + * + * 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 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 REGENTS 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. + * + * from: @(#)brk.s 5.2 (Berkeley) 12/17/90 + */ + +#include <machine/asm.h> +__FBSDID("$FreeBSD$"); +#include "SYS.h" + + .globl _C_LABEL(_end) + .globl CURBRK + +#ifdef WEAK_ALIAS +WEAK_ALIAS(brk, _brk) +#endif + + .data + .align 0 + .globl _C_LABEL(minbrk) + .type _C_LABEL(minbrk),#object +_C_LABEL(minbrk): + .word _C_LABEL(_end) + +/* + * Change the data segment size + */ +ENTRY(_brk) +#ifdef PIC + /* Setup the GOT */ + ldr r3, .Lgot + add r3, pc, r3 +.L1: + ldr r1, .Lminbrk + ldr r1, [r3, r1] +#else + ldr r1, .Lminbrk +#endif + /* Get the minimum allowable brk address */ + ldr r1, [r1] + + /* + * Valid the address specified and set to the minimum + * if the address is below minbrk. + */ + cmp r0, r1 + movlt r0, r1 + mov r2, r0 + SYSTRAP(break) + bcs PIC_SYM(CERROR, PLT) + +#ifdef PIC + ldr r1, .Lcurbrk + ldr r1, [r3, r1] +#else + ldr r1, .Lcurbrk +#endif + /* Store the new address in curbrk */ + str r2, [r1] + + /* Return 0 for success */ + mov r0, #0x00000000 + RET + + .align 2 +#ifdef PIC +.Lgot: + .word _GLOBAL_OFFSET_TABLE_ - (.L1+4) +#endif +.Lminbrk: + .word PIC_SYM(_C_LABEL(minbrk), GOT) +.Lcurbrk: + .word PIC_SYM(CURBRK, GOT) |