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1 files changed, 84 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/alpha/brk.S b/sysdeps/unix/sysv/linux/alpha/brk.S
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+/* Copyright (C) 1993-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Brendan Kehoe <brendan@zen.org>, 1993.
+
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* __brk is a special syscall under Linux since it never returns an
+   error.  Instead, the error condition is indicated by returning the old
+   break value (instead of the new, requested one).  */
+
+#include <sysdep.h>
+#define _ERRNO_H
+#include <bits/errno.h>
+
+#ifdef PIC
+.section .bss
+	.align 3
+	.globl __curbrk
+__curbrk: .skip 8
+	.type __curbrk,@object
+	.size __curbrk,8
+#else
+.comm __curbrk, 8
+#endif
+
+	.text
+	.align	4
+	.globl	__brk
+	.ent	__brk
+	.usepv	__brk, std
+
+	cfi_startproc
+__brk:
+	ldgp	gp, 0(t12)
+	subq	sp, 16, sp
+	cfi_adjust_cfa_offset (16)
+#ifdef PROF
+	.set noat
+	lda	AT, _mcount
+	jsr	AT, (AT), _mcount
+	.set at
+#endif
+
+	/* Save the requested brk across the system call.  */
+	stq	a0, 0(sp)
+
+	ldiq	v0, __NR_brk
+	call_pal PAL_callsys
+
+	ldq	a0, 0(sp)
+	addq	sp, 16, sp
+	cfi_adjust_cfa_offset (-16)
+
+	/* Be prepared for an OSF-style brk.  */
+	bne	a3, SYSCALL_ERROR_LABEL
+	beq	v0, $ok
+
+	/* Correctly handle the brk(0) query case.  */
+	cmoveq	a0, v0, a0
+	xor	a0, v0, t0
+	lda	v0, ENOMEM
+	bne	t0, SYSCALL_ERROR_LABEL
+
+	/* Update __curbrk and return cleanly.  */
+	lda	v0, 0
+$ok:	stq	a0, __curbrk
+	ret
+
+PSEUDO_END(__brk)
+	cfi_endproc
+
+weak_alias (__brk, brk)