[PATCH v2 03/16] Consolidate Linux msgrcv implementation

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

Changes from previous version:

  - Use __ASSUME_SYSVIPC_SYSCALL instead of __NR_syscall to issue the
    wired syscall or the ipc one.

--

This patch consolidates the msgrcv Linux implementation in only
one default file, sysdeps/unix/sysv/linux/msgrcv.c.  If tries to use
the direct syscall if it is supported, otherwise will use the old ipc
multiplex mechanism.

Checked on x86_64, i686, powerpc64le, aarch64, and armhf.

	* sysdeps/unix/sysv/linux/msgrcv.c (__libc_msgrcv): Use msgrcv syscall
	if defined.
	* sysdeps/unix/sysv/linux/sparc/sparc64/msgrcv.c: Remove file.
---
 ChangeLog                                      |  4 ++++
 sysdeps/unix/sysv/linux/msgrcv.c               | 25 ++++++++------------
 sysdeps/unix/sysv/linux/sparc/sparc64/msgrcv.c | 32 --------------------------
 3 files changed, 13 insertions(+), 48 deletions(-)
 delete mode 100644 sysdeps/unix/sysv/linux/sparc/sparc64/msgrcv.c

diff --git a/sysdeps/unix/sysv/linux/msgrcv.c b/sysdeps/unix/sysv/linux/msgrcv.c
index c4dd219..f4e25ba 100644
--- a/sysdeps/unix/sysv/linux/msgrcv.c
+++ b/sysdeps/unix/sysv/linux/msgrcv.c
@@ -16,33 +16,26 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-#include <errno.h>
 #include <sys/msg.h>
 #include <ipc_priv.h>
-
 #include <sysdep-cancel.h>
-#include <sys/syscall.h>
-
-/* Kludge to work around Linux' restriction of only up to five
-   arguments to a system call.  */
-struct ipc_kludge
-  {
-    void *msgp;
-    long int msgtyp;
-  };
-
 
 ssize_t
 __libc_msgrcv (int msqid, void *msgp, size_t msgsz, long int msgtyp,
 	       int msgflg)
 {
+#ifdef __ASSUME_SYSVIPC_SYSCALL
+  return SYSCALL_CANCEL (msgrc, msqid, msgp, msgsz, msgtyp, msgflg);
+#else
   /* The problem here is that Linux' calling convention only allows up to
      fives parameters to a system call.  */
-  struct ipc_kludge tmp;
-
-  tmp.msgp = msgp;
-  tmp.msgtyp = msgtyp;
+  struct
+  {
+    void *msgp;
+    long int msgtyp;
+  } tmp = { msgp, msgtyp };
 
   return SYSCALL_CANCEL (ipc, IPCOP_msgrcv, msqid, msgsz, msgflg, &tmp);
+#endif
 }
 weak_alias (__libc_msgrcv, msgrcv)
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/msgrcv.c b/sysdeps/unix/sysv/linux/sparc/sparc64/msgrcv.c
deleted file mode 100644
index ccaa4ee..0000000
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/msgrcv.c
+++ /dev/null
@@ -1,32 +0,0 @@
-/* Copyright (C) 2010-2016 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   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, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <sys/msg.h>
-#include <ipc_priv.h>
-
-#include <sysdep-cancel.h>
-#include <sys/syscall.h>
-
-ssize_t
-__libc_msgrcv (int msqid, void *msgp, size_t msgsz, long int msgtyp,
-	       int msgflg)
-{
-  return SYSCALL_CANCEL (ipc, IPCOP_msgrcv, msqid, msgsz, msgflg,
-			 msgp, msgtyp);
-}
-weak_alias (__libc_msgrcv, msgrcv)
-- 
2.7.4