[PATCH 1/4] Add INTERNAL_SYSCALL_CALL
Adhemerval Zanella
adhemerval.zanella@linaro.org
Tue Sep 20 15:02:00 GMT 2016
This patch adds two new macros for internal and inline syscall to use
within GLIBC: INTERNAL_SYSCALL_CALL and INLINE_SYSCALL_CALL. They are
similar to the old INTERNAL_SYSCALL and INLINE_SYSCALL with the difference
the new macros accept a variable argument call and do not require to pass
the expected argument size.
The advantage is it is possible to use variable argument macros like
SYSCALL_LL{64} without the need to also handle the argument size. So
for an ABI where SYSCALL_LL might split the argument in high and low
parts, instead of:
INTERNAL_SYSCALL_DECL (err);
#if ...
INTERNAL_SYSCALL (syscall, err, 2, SYSCALL_LL (len));
#else
INTERNAL_SYSCALL (syscall, err, 1, SYSCALL_LL (len));
#endif
It will be just:
INTERNAL_SYSCALL_CALL (syscall, err, SYSCALL_LL (len));
The INLINE_SYSCALL_CALL follows the same semanthic regarding the argument
and is similar to INLINE_SYSCALL regarding setting errno.
No function currently uses these new macros, so no code change is expected.
* sysdeps/unix/sysdep.h (__INTERNAL_SYSCALL0): New macro.
(__INTERNAL_SYSCALL1): Likewise.
(__INTERNAL_SYSCALL2): Likewise.
(__INTERNAL_SYSCALL3): Likewise.
(__INTERNAL_SYSCALL4): Likewise.
(__INTERNAL_SYSCALL5): Likewise.
(__INTERNAL_SYSCALL6): Likewise.
(__INTERNAL_SYSCALL7): Likewise.
(__INTERNAL_SYSCALL_NARGS_X): Likewise.
(__INTERNAL_SYSCALL_NARGS): Likewise.
(__INTERNAL_SYSCALL_CONCAT_X): Likewise.
(__INTERNAL_SYSCALL_CONCAT): Likewise.
(__INTERNAL_SYSCALL_DISP): Likewise.
(INTERNAL_SYSCALL_CALL): Likewise.
(__SYSCALL_CALL): Rename to INLINE_SYSCALL_CALL.
(SYSCALL_CANCEL): Replace __SYSCALL_CALL with INLINE_SYSCALL_CALL.
---
sysdeps/unix/sysdep.h | 43 ++++++++++++++++++++++++++++++++++++++++---
1 file changed, 40 insertions(+), 3 deletions(-)
diff --git a/sysdeps/unix/sysdep.h b/sysdeps/unix/sysdep.h
index 94a2ce0..50ac4d1 100644
--- a/sysdeps/unix/sysdep.h
+++ b/sysdeps/unix/sysdep.h
@@ -24,6 +24,38 @@
#define SYSCALL__(name, args) PSEUDO (__##name, name, args)
#define SYSCALL(name, args) PSEUDO (name, name, args)
+#define __INTERNAL_SYSCALL0(name, err) \
+ INTERNAL_SYSCALL (name, err, 0)
+#define __INTERNAL_SYSCALL1(name, err, a1) \
+ INTERNAL_SYSCALL (name, err, 1, a1)
+#define __INTERNAL_SYSCALL2(name, err, a1, a2) \
+ INTERNAL_SYSCALL (name, err, 2, a1, a2)
+#define __INTERNAL_SYSCALL3(name, err, a1, a2, a3) \
+ INTERNAL_SYSCALL (name, err, 3, a1, a2, a3)
+#define __INTERNAL_SYSCALL4(name, err, a1, a2, a3, a4) \
+ INTERNAL_SYSCALL (name, err, 4, a1, a2, a3, a4)
+#define __INTERNAL_SYSCALL5(name, err, a1, a2, a3, a4, a5) \
+ INTERNAL_SYSCALL (name, err, 5, a1, a2, a3, a4, a5)
+#define __INTERNAL_SYSCALL6(name, err, a1, a2, a3, a4, a5, a6) \
+ INTERNAL_SYSCALL (name, err, 6, a1, a2, a3, a4, a5, a6)
+#define __INTERNAL_SYSCALL7(name, err, a1, a2, a3, a4, a5, a6, a7) \
+ INTERNAL_SYSCALL (name, err, 7, a1, a2, a3, a4, a5, a6, a7)
+
+#define __INTERNAL_SYSCALL_NARGS_X(a, b, c, d, e, f, g, h, n, ...) n
+#define __INTERNAL_SYSCALL_NARGS(...) \
+ __INTERNAL_SYSCALL_NARGS_X (__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0, )
+#define __INTERNAL_SYSCALL_CONCAT_X(a, b) a##b
+#define __INTERNAL_SYSCALL_CONCAT(a, b) __SYSCALL_CONCAT_X (a, b)
+#define __INTERNAL_SYSCALL_DISP(b,err,...) \
+ __INTERNAL_SYSCALL_CONCAT (b, __SYSCALL_NARGS (__VA_ARGS__)) \
+ (err, __VA_ARGS__)
+
+/* Issue a syscall defined by syscall number plus any other argument required.
+ It is similar to INTERNAL_SYSCALL macro, but without the need to pass the
+ expected argument number as second parameter. */
+#define INTERNAL_SYSCALL_CALL(nr, err, ...) \
+ __INTERNAL_SYSCALL_DISP (__INTERNAL_SYSCALL, nr, err, __VA_ARGS__)
+
#define __SYSCALL0(name) \
INLINE_SYSCALL (name, 0)
#define __SYSCALL1(name, a1) \
@@ -49,17 +81,22 @@
#define __SYSCALL_DISP(b,...) \
__SYSCALL_CONCAT (b,__SYSCALL_NARGS(__VA_ARGS__))(__VA_ARGS__)
-#define __SYSCALL_CALL(...) __SYSCALL_DISP (__SYSCALL, __VA_ARGS__)
+/* Issue a syscall defined by syscall number plus any other argument required.
+ Any error will be handled using arch defined macros and errno will be se
+ accordingly.
+ It is similar to INLINE_SYSCALL macro, but without the need to pass the
+ expected argument number as second parameter. */
+#define INLINE_SYSCALL_CALL(...) __SYSCALL_DISP (__SYSCALL, __VA_ARGS__)
#define SYSCALL_CANCEL(...) \
({ \
long int sc_ret; \
if (SINGLE_THREAD_P) \
- sc_ret = __SYSCALL_CALL (__VA_ARGS__); \
+ sc_ret = INLINE_SYSCALL_CALL (__VA_ARGS__); \
else \
{ \
int sc_cancel_oldtype = LIBC_CANCEL_ASYNC (); \
- sc_ret = __SYSCALL_CALL (__VA_ARGS__); \
+ sc_ret = INLINE_SYSCALL_CALL (__VA_ARGS__); \
LIBC_CANCEL_RESET (sc_cancel_oldtype); \
} \
sc_ret; \
--
2.7.4
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