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+/* Copyright (C) 1992, 93, 1995-2000, 2002, 2003 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 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 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 (0x900000)
+#define SYS_ify(syscall_name) (__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 R0
+ 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 (syscall_name, args); \
+ cmn r0, $4096;
+
+#define PSEUDO_RET \
+ RETINSTR(cc, lr); \
+ b PLTJMP(SYSCALL_ERROR)
+#undef ret
+#define ret PSEUDO_RET
+
+#undef PSEUDO_END
+#define PSEUDO_END(name) \
+ SYSCALL_ERROR_HANDLER \
+ END (name)
+
+#undef PSEUDO_NOERRNO
+#define PSEUDO_NOERRNO(name, syscall_name, args) \
+ .text; \
+ ENTRY (name); \
+ DO_CALL (syscall_name, args);
+
+#define PSEUDO_RET_NOERRNO \
+ DO_RET (lr);
+
+#undef ret_NOERRNO
+#define ret_NOERRNO PSEUDO_RET_NOERRNO
+
+#undef PSEUDO_END_NOERRNO
+#define PSEUDO_END_NOERRNO(name) \
+ END (name)
+
+/* The function has to return the error code. */
+#undef PSEUDO_ERRVAL
+#define PSEUDO_ERRVAL(name, syscall_name, args) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args); \
+ rsb r0, r0, #0
+
+#undef PSEUDO_END_ERRVAL
+#define PSEUDO_END_ERRVAL(name) \
+ END (name)
+
+#define ret_ERRVAL PSEUDO_RET_NOERRNO
+
+#if NOT_IN_libc
+# define SYSCALL_ERROR __local_syscall_error
+# define SYSCALL_ERROR_HANDLER \
+__local_syscall_error: \
+ str lr, [sp, #-4]!; \
+ str r0, [sp, #-4]!; \
+ bl PLTJMP(C_SYMBOL_NAME(__errno_location)); \
+ ldr r1, [sp], #4; \
+ rsb r1, r1, #0; \
+ str r1, [r0]; \
+ mvn r0, #0; \
+ ldr pc, [sp], #4;
+#else
+# define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */
+# define SYSCALL_ERROR __syscall_error
+#endif
+
+/* Linux takes system call args in registers:
+ syscall number in the SWI instruction
+ arg 1 r0
+ arg 2 r1
+ arg 3 r2
+ arg 4 r3
+ arg 5 r4 (this is different from the APCS convention)
+ arg 6 r5
+ arg 7 r6
+
+ The compiler is going to form a call by coming here, through PSEUDO, with
+ arguments
+ syscall number in the DO_CALL macro
+ arg 1 r0
+ arg 2 r1
+ arg 3 r2
+ arg 4 r3
+ arg 5 [sp]
+ arg 6 [sp+4]
+ arg 7 [sp+8]
+
+ We need to shuffle values between R4..R6 and the stack so that the
+ caller's v1..v3 and stack frame are not corrupted, and the kernel
+ sees the right arguments.
+
+*/
+
+#undef DO_CALL
+#define DO_CALL(syscall_name, args) \
+ DOARGS_##args \
+ swi SYS_ify (syscall_name); \
+ UNDOARGS_##args
+
+#define DOARGS_0 /* nothing */
+#define DOARGS_1 /* nothing */
+#define DOARGS_2 /* nothing */
+#define DOARGS_3 /* nothing */
+#define DOARGS_4 /* nothing */
+#define DOARGS_5 str r4, [sp, $-4]!; ldr r4, [sp, $4];
+#define DOARGS_6 mov ip, sp; stmfd sp!, {r4, r5}; ldmia ip, {r4, r5};
+#define DOARGS_7 mov ip, sp; stmfd sp!, {r4, r5, r6}; ldmia ip, {r4, r5, r6};
+
+#define UNDOARGS_0 /* nothing */
+#define UNDOARGS_1 /* nothing */
+#define UNDOARGS_2 /* nothing */
+#define UNDOARGS_3 /* nothing */
+#define UNDOARGS_4 /* nothing */
+#define UNDOARGS_5 ldr r4, [sp], $4;
+#define UNDOARGS_6 ldmfd sp!, {r4, r5};
+#define UNDOARGS_7 ldmfd sp!, {r4, r5, r6};
+
+#else /* not __ASSEMBLER__ */
+
+/* Define a macro which expands into the inline wrapper code for a system
+ call. */
+#undef INLINE_SYSCALL
+#define INLINE_SYSCALL(name, nr, args...) \
+ ({ unsigned int _sys_result = INTERNAL_SYSCALL (name, , nr, args); \
+ if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (_sys_result, ), 0)) \
+ { \
+ __set_errno (INTERNAL_SYSCALL_ERRNO (_sys_result, )); \
+ _sys_result = (unsigned int) -1; \
+ } \
+ (int) _sys_result; })
+
+#undef INTERNAL_SYSCALL_DECL
+#define INTERNAL_SYSCALL_DECL(err) do { } while (0)
+
+#undef INTERNAL_SYSCALL
+#define INTERNAL_SYSCALL(name, err, nr, args...) \
+ ({ unsigned int _sys_result; \
+ { \
+ register int _a1 asm ("a1"); \
+ LOAD_ARGS_##nr (args) \
+ asm volatile ("swi %1 @ syscall " #name \
+ : "=r" (_a1) \
+ : "i" (SYS_ify(name)) ASM_ARGS_##nr \
+ : "memory"); \
+ _sys_result = _a1; \
+ } \
+ (int) _sys_result; })
+
+#undef INTERNAL_SYSCALL_ERROR_P
+#define INTERNAL_SYSCALL_ERROR_P(val, err) \
+ ((unsigned int) (val) >= 0xfffff001u)
+
+#undef INTERNAL_SYSCALL_ERRNO
+#define INTERNAL_SYSCALL_ERRNO(val, err) (-(val))
+
+#define LOAD_ARGS_0()
+#define ASM_ARGS_0
+#define LOAD_ARGS_1(a1) \
+ _a1 = (int) (a1); \
+ LOAD_ARGS_0 ()
+#define ASM_ARGS_1 ASM_ARGS_0, "r" (_a1)
+#define LOAD_ARGS_2(a1, a2) \
+ register int _a2 asm ("a2") = (int) (a2); \
+ LOAD_ARGS_1 (a1)
+#define ASM_ARGS_2 ASM_ARGS_1, "r" (_a2)
+#define LOAD_ARGS_3(a1, a2, a3) \
+ register int _a3 asm ("a3") = (int) (a3); \
+ LOAD_ARGS_2 (a1, a2)
+#define ASM_ARGS_3 ASM_ARGS_2, "r" (_a3)
+#define LOAD_ARGS_4(a1, a2, a3, a4) \
+ register int _a4 asm ("a4") = (int) (a4); \
+ LOAD_ARGS_3 (a1, a2, a3)
+#define ASM_ARGS_4 ASM_ARGS_3, "r" (_a4)
+#define LOAD_ARGS_5(a1, a2, a3, a4, a5) \
+ register int _v1 asm ("v1") = (int) (a5); \
+ LOAD_ARGS_4 (a1, a2, a3, a4)
+#define ASM_ARGS_5 ASM_ARGS_4, "r" (_v1)
+#define LOAD_ARGS_6(a1, a2, a3, a4, a5, a6) \
+ register int _v2 asm ("v2") = (int) (a6); \
+ LOAD_ARGS_5 (a1, a2, a3, a4, a5)
+#define ASM_ARGS_6 ASM_ARGS_5, "r" (_v2)
+#define LOAD_ARGS_7(a1, a2, a3, a4, a5, a6, a7) \
+ register int _v3 asm ("v3") = (int) (a7); \
+ LOAD_ARGS_6 (a1, a2, a3, a4, a5, a6)
+#define ASM_ARGS_7 ASM_ARGS_6, "r" (_v3)
+
+#endif /* __ASSEMBLER__ */
+
+#endif /* linux/arm/sysdep.h */