Linux: consolidate sendfile implementation

This is similar to other LFS consolidation, where the non-LFS is only
built if __OFF_T_MATCHES_OFF64_T is not defined and the LFS version
is aliased to non-LFS name if __OFF_T_MATCHES_OFF64_T is defined.

For non-LFS variant, use sendfile syscall if defined, otherwise use
sendfile64 plus the offset overflow check (as generic implementation).

Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>

sysdeps/unix/sysv/linux/mips/mips64/n64/sendfile64.c

@@ -1 +0,0 @@
-/* sendfile64 is alias of sendfile syscall.  */

sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list

@@ -1,3 +0,0 @@
-# File name	Caller	Syscall name	# args	Strong name	Weak names
-
-sendfile	-	sendfile	i:iipi	sendfile	sendfile64

sysdeps/unix/sysv/linux/sendfile.c

@@ -1,4 +1,5 @@
-/* Copyright (C) 2011-2022 Free Software Foundation, Inc.
+/* Transfer data between file descriptors.  Linux version.
+   Copyright (C) 2011-2022 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
@@ -20,11 +21,16 @@
 #include <errno.h>
 #include <sysdep.h>
 
+#ifndef __OFF_T_MATCHES_OFF64_T
+
 /* Send COUNT bytes from file associated with IN_FD starting at OFFSET to
    descriptor OUT_FD.  */
 ssize_t
 sendfile (int out_fd, int in_fd, off_t *offset, size_t count)
 {
+# ifdef __NR_sendfile
+  return INLINE_SYSCALL_CALL (sendfile, out_fd, in_fd, offset, count);
+# else
   __off64_t off64;
   int rc;
 
@@ -38,9 +44,12 @@ sendfile (int out_fd, int in_fd, off_t *offset, size_t count)
       off64 = *offset;
     }
 
-  rc = INLINE_SYSCALL (sendfile64, 4, out_fd, in_fd,
-                       offset ? &off64 : NULL, count);
+  rc = INLINE_SYSCALL_CALL (sendfile64, out_fd, in_fd, offset ? &off64 : NULL,
+			    count);
   if (offset)
     *offset = off64;
   return rc;
+# endif
 }
+
+#endif

sysdeps/unix/sysv/linux/sendfile64.c

@@ -0,0 +1,37 @@
+/* Transfer data between file descriptors.  Linux version.
+   Copyright (C) 2022 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
+   <https://www.gnu.org/licenses/>.  */
+
+#include <sys/sendfile.h>
+#include <stddef.h>
+#include <errno.h>
+#include <sysdep.h>
+
+/* Send COUNT bytes from file associated with IN_FD starting at OFFSET to
+   descriptor OUT_FD.  */
+ssize_t
+sendfile64 (int out_fd, int in_fd, off64_t *offset, size_t count)
+{
+#ifndef __NR_sendfile64
+# define __NR_sendfile64 __NR_sendfile
+#endif
+  return INLINE_SYSCALL_CALL (sendfile64, out_fd, in_fd, offset, count);
+}
+
+#ifdef __OFF_T_MATCHES_OFF64_T
+strong_alias (sendfile64, sendfile)
+#endif

sysdeps/unix/sysv/linux/syscalls.list

@@ -62,8 +62,6 @@ sched_primin	-	sched_get_priority_min	i:i	__sched_get_priority_min	sched_get_pri
 sched_setp	-	sched_setparam	i:ip	__sched_setparam	sched_setparam
 sched_sets	-	sched_setscheduler	i:iip	__sched_setscheduler	sched_setscheduler
 sched_yield	-	sched_yield	i:	__sched_yield	sched_yield
-sendfile	-	sendfile	i:iipU	sendfile
-sendfile64	-	sendfile64	i:iipU	sendfile64
 setfsgid	EXTRA	setfsgid	i:i	setfsgid
 setfsuid	EXTRA	setfsuid	i:i	setfsuid
 setpgid		-	setpgid		i:ii	__setpgid	setpgid

sysdeps/unix/sysv/linux/wordsize-64/sendfile64.c

@@ -1 +0,0 @@
-/* sendfile64 is alias of sendfile syscall.  */

sysdeps/unix/sysv/linux/wordsize-64/syscalls.list

@@ -1,4 +1,3 @@
 # File name	Caller	Syscall name	# args	Strong name	Weak names
 
-sendfile	-	sendfile	i:iipi	sendfile	sendfile64
 personality	EXTRA	personality	i:i	__personality	personality