diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/arm/sysdep.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/arm/sysdep.h | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/arm/sysdep.h b/sysdeps/unix/sysv/linux/arm/sysdep.h new file mode 100644 index 0000000000..6478a5d182 --- /dev/null +++ b/sysdeps/unix/sysv/linux/arm/sysdep.h @@ -0,0 +1,73 @@ +/* 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 */ |