1 files changed, 91 insertions, 0 deletions
diff --git a/lib/libc/amd64/sys/brk.S b/lib/libc/amd64/sys/brk.S
new file mode 100644
index 0000000..e884ac2
--- /dev/null
+++ b/lib/libc/amd64/sys/brk.S
@@ -0,0 +1,91 @@
+/*-
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * William Jolitz.
+ *
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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.
+ *
+ *	$Id: brk.S,v 1.3 1994/02/21 05:13:26 rgrimes Exp $
+ */
+
+#if defined(SYSLIBC_SCCS) && !defined(lint)
+	.asciz "@(#)brk.s	5.2 (Berkeley) 12/17/90"
+#endif /* SYSLIBC_SCCS and not lint */
+
+#include "SYS.h"
+
+#define	SYS_brk		17
+
+	.globl	curbrk
+	.globl	minbrk
+ENTRY(_brk)
+	jmp	ok
+
+ENTRY(brk)
+#ifdef PIC
+	movl	4(%esp),%eax
+	PIC_PROLOGUE
+	movl	PIC_GOT(curbrk),%edx	# set up GOT addressing
+	movl	PIC_GOT(minbrk),%ecx	#
+	cmpl	%eax,(%ecx)
+	PIC_EPILOGUE
+	jl	ok
+	movl	(%ecx),%eax
+	movl	%eax,4(%esp)
+ok:
+	lea	SYS_brk,%eax
+	LCALL(7,0)
+	jb	err
+	movl	4(%esp),%eax
+	movl	%eax,(%edx)
+	movl	$0,%eax
+	ret
+err:
+	jmp	PIC_PLT(cerror)
+
+#else
+
+	movl	4(%esp),%eax
+	cmpl	%eax,minbrk
+	jl	ok
+	movl	minbrk,%eax
+	movl	%eax,4(%esp)
+ok:
+	lea	SYS_brk,%eax
+	LCALL(7,0)
+	jb	err
+	movl	4(%esp),%eax
+	movl	%eax,curbrk
+	movl	$0,%eax
+	ret
+err:
+	jmp	cerror
+#endif