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+/* Copyright (C) 1992, 93, 95, 96, 97 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+Contributed by Ulrich Drepper, <drepper@gnu.ai.mit.edu>, August 1995.
+ARM changes by Philip Blundell, <pjb27@cam.ac.uk>, May 1997.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#ifndef _LINUX_ARM_SYSDEP_H
+#define _LINUX_ARM_SYSDEP_H 1
+
+/* There is some commonality. */
+#include <sysdeps/unix/arm/sysdep.h>
+
+/* For Linux we can use the system call table in the header file
+ /usr/include/asm/unistd.h
+ of the kernel. But these symbols do not follow the SYS_* syntax
+ so we have to redefine the `SYS_ify' macro here. */
+#undef SYS_ify
+#define SWI_BASE (9 << 20)
+#define SYS_ify(syscall_name) (SWI_BASE + __NR_##syscall_name)
+
+
+#ifdef ASSEMBLER
+
+/* Linux uses a negative return value to indicate syscall errors,
+ unlike most Unices, which use the condition codes' carry flag.
+
+ Since version 2.1 the return value of a system call might be
+ negative even if the call succeeded. E.g., the `lseek' system call
+ might return a large offset. Therefore we must not anymore test
+ for < 0, but test for a real error by making sure the value in %eax
+ is a real error number. Linus said he will make sure the no syscall
+ returns a value in -1 .. -4095 as a valid result so we can savely
+ test with -4095. */
+#undef PSEUDO
+#define PSEUDO(name, syscall_name, args) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (args, syscall_name); \
+ cmn r0, $4096; \
+ bge syscall_error;
+
+#undef PSEUDO_END
+#define PSEUDO_END(name) \
+ SYSCALL_ERROR_HANDLER \
+ END (name)
+
+#ifndef PIC
+#define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */
+#else
+#error Aiee
+#endif /* PIC */
+
+#undef DO_CALL
+#define DO_CALL(args, syscall_name) \
+ swi SYS_ify (syscall_name);
+
+#endif /* ASSEMBLER */
+
+#endif /* linux/arm/sysdep.h */