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Support and use mixed compat/non-compat aliases in syscalls.list
- From: "Joseph S. Myers" <joseph at codesourcery dot com>
- To: <libc-alpha at sourceware dot org>
- Date: Wed, 24 Sep 2014 09:33:33 +0000
- Subject: Support and use mixed compat/non-compat aliases in syscalls.list
- Authentication-results: sourceware.org; auth=none
This patch, relative to a tree with
<https://sourceware.org/ml/libc-alpha/2014-09/msg00546.html> (pending
review) applied, enables syscalls.list entries to specify both compat
and non-compat symbol versions for the same syscall definition, making
use of this for setrlimit / chown / lchown where the inability to
specify such aliases showed up in the course of work on bug 14138.
The change to make-syscalls.sh is minimal: adding a SHARED conditional
on the compat_symbol calls. It remains the case that if a compat
symbol version is specified, the syscall is only built for the shared
library at all if an explicit symbol version is given for a non-compat
symbol (so it's necessary to specify "lchown@@GLIBC_2.0
chown@GLIBC_2.0" rather than just "lchown chown@GLIBC_2.0"). It also
remains the case, as already commented in make-syscalls.sh, that no
SHLIB_COMPAT conditionals are generated, so there would be problems if
the same syscalls.list file, with compat symbols, were used for both
configurations that should have those symbols and configurations for
which they should be conditioned out with SHLIB_COMPAT.
Tested for x86.
2014-09-24 Joseph Myers <joseph@codesourcery.com>
* sysdeps/unix/make-syscalls.sh (emit_weak_aliases): Condition
compat_symbol calls on [SHARED].
* sysdeps/unix/sysv/linux/i386/chown.c: Remove file.
* sysdeps/unix/sysv/linux/powerpc/lchown.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/chown.c: Likewise.
* sysdeps/unix/sysv/linux/i386/syscalls.list (newchown): Change to
chown.
(lchown): Specify symbol version for lchown alias. Add
chown@GLIBC_2.0 alias.
(oldsetrlimit): Remove.
(setrlimit): Add setrlimit@GLIBC_2.0 alias.
* sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list
(oldsetrlimit): Remove.
(setrlimit): Add setrlimit@GLIBC_2.0 alias.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
(lchown): New syscall entry.
(oldsetrlimit): Remove.
(setrlimit): Add setrlimit@GLIBC_2.0 alias.
* sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list (newchown):
Change to chown.
(lchown): Specify symbol version for lchown alias. Add
chown@GLIBC_2.0 alias.
(oldsetrlimit): Remove.
(setrlimit): Add setrlimit@GLIBC_2.0 alias.
diff --git a/sysdeps/unix/make-syscalls.sh b/sysdeps/unix/make-syscalls.sh
index 6eba62c..fd6ebb4 100644
--- a/sysdeps/unix/make-syscalls.sh
+++ b/sysdeps/unix/make-syscalls.sh
@@ -113,7 +113,7 @@ emit_weak_aliases()
*@*)
base=`echo $name | sed 's/@.*//'`
ver=`echo $name | sed 's/.*@//;s/\./_/g'`
- echo " echo '#ifndef NOT_IN_libc'; \\"
+ echo " echo '#if defined SHARED && !defined NOT_IN_libc'; \\"
if test -z "$vcount" ; then
source=$strong
vcount=1
diff --git a/sysdeps/unix/sysv/linux/i386/chown.c b/sysdeps/unix/sysv/linux/i386/chown.c
deleted file mode 100644
index b46b80e..0000000
--- a/sysdeps/unix/sysv/linux/i386/chown.c
+++ /dev/null
@@ -1,53 +0,0 @@
-/* Copyright (C) 1998-2014 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 <unistd.h>
-
-#include <sysdep.h>
-#include <sys/syscall.h>
-#include <shlib-compat.h>
-
-#include <linux/posix_types.h>
-
-/*
- In Linux 2.1.x the chown functions have been changed. A new function lchown
- was introduced. The new chown now follows symlinks - the old chown and the
- new lchown do not follow symlinks.
- The new lchown function has the same number as the old chown had and the
- new chown has a new number. When compiling with headers from Linux > 2.1.8x
- it's impossible to run this libc with older kernels. In these cases libc
- has therefore to route calls to chown to the old chown function.
-*/
-
-extern int __chown_is_lchown (const char *__file, uid_t __owner,
- gid_t __group);
-
-
-#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-/* Compiling for compatibility. */
-int
-attribute_compat_text_section
-__chown_is_lchown (const char *file, uid_t owner, gid_t group)
-{
- return __lchown (file, owner, group);
-}
-#endif
-
-#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-compat_symbol (libc, __chown_is_lchown, chown, GLIBC_2_0);
-#endif
diff --git a/sysdeps/unix/sysv/linux/i386/syscalls.list b/sysdeps/unix/sysv/linux/i386/syscalls.list
index bcd9d74..db375a8 100644
--- a/sysdeps/unix/sysv/linux/i386/syscalls.list
+++ b/sysdeps/unix/sysv/linux/i386/syscalls.list
@@ -1,15 +1,14 @@
# File name Caller Syscall name Args Strong name Weak names
-newchown EXTRA chown32 i:sii __chown chown@@GLIBC_2.1
-lchown - lchown32 i:sii __lchown lchown
+chown - chown32 i:sii __chown chown@@GLIBC_2.1
+lchown - lchown32 i:sii __lchown lchown@@GLIBC_2.0 chown@GLIBC_2.0
fchown - fchown32 i:iii __fchown fchown
modify_ldt EXTRA modify_ldt i:ipi __modify_ldt modify_ldt
vm86old EXTRA vm86old i:p __vm86old vm86@GLIBC_2.0
vm86 - vm86 i:ip __vm86 vm86@@GLIBC_2.3.4
oldgetrlimit EXTRA getrlimit i:ip __old_getrlimit getrlimit@GLIBC_2.0
-oldsetrlimit EXTRA setrlimit i:ip __old_setrlimit setrlimit@GLIBC_2.0
-setrlimit - setrlimit i:ip __setrlimit setrlimit@@GLIBC_2.2
+setrlimit - setrlimit i:ip __setrlimit setrlimit@GLIBC_2.0 setrlimit@@GLIBC_2.2
waitpid - waitpid Ci:ipi __waitpid waitpid __libc_waitpid
prlimit64 EXTRA prlimit64 i:iipp prlimit64
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list b/sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list
index 6f10536..b0ad689 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list
@@ -1,5 +1,4 @@
# File name Caller Syscall name Args Strong name Weak names
oldgetrlimit EXTRA getrlimit i:ip __old_getrlimit getrlimit@GLIBC_2.0
-oldsetrlimit EXTRA setrlimit i:ip __old_setrlimit setrlimit@GLIBC_2.0
-setrlimit - setrlimit i:ip __setrlimit setrlimit@@GLIBC_2.2
+setrlimit - setrlimit i:ip __setrlimit setrlimit@GLIBC_2.0 setrlimit@@GLIBC_2.2
diff --git a/sysdeps/unix/sysv/linux/powerpc/lchown.S b/sysdeps/unix/sysv/linux/powerpc/lchown.S
deleted file mode 100644
index 1785748..0000000
--- a/sysdeps/unix/sysv/linux/powerpc/lchown.S
+++ /dev/null
@@ -1,38 +0,0 @@
-/* lchown system call.
- Copyright (C) 1998-2014 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/>. */
-
-/* Some old kernel headers call lchown() 'chown'. The number is
- the same. */
-
-#include <sysdep.h>
-
-#ifdef __NR_lchown
- PSEUDO (__lchown, lchown, 3)
-#else
- PSEUDO (__lchown, chown, 3)
-#endif
- ret
- PSEUDO_END(__lchown)
- weak_alias (__lchown, lchown)
-
-#ifdef SHARED
-#include <shlib-compat.h>
-# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-compat_symbol (libc, __lchown, chown, GLIBC_2_0)
-# endif
-#endif
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list b/sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
index 25487cc..451d508 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
@@ -1,11 +1,11 @@
# File name Caller Syscall name # args Strong name Weak names
chown - chown i:sii __chown chown@@GLIBC_2.1
+lchown - lchown i:sii __lchown lchown@@GLIBC_2.0 chown@GLIBC_2.0
# System calls with wrappers.
oldgetrlimit EXTRA getrlimit i:ip __old_getrlimit getrlimit@GLIBC_2.0
-oldsetrlimit EXTRA setrlimit i:ip __old_setrlimit setrlimit@GLIBC_2.0
-setrlimit - setrlimit i:ip __setrlimit setrlimit@@GLIBC_2.2
+setrlimit - setrlimit i:ip __setrlimit setrlimit@GLIBC_2.0 setrlimit@@GLIBC_2.2
# Due to 64bit alignment there is a dummy second parameter
readahead - readahead i:iiiii __readahead readahead
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/chown.c b/sysdeps/unix/sysv/linux/s390/s390-32/chown.c
deleted file mode 100644
index d1e3aa4..0000000
--- a/sysdeps/unix/sysv/linux/s390/s390-32/chown.c
+++ /dev/null
@@ -1,54 +0,0 @@
-/* Copyright (C) 2000-2014 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 <unistd.h>
-
-#include <sysdep.h>
-#include <sys/syscall.h>
-#include <shlib-compat.h>
-
-#include <linux/posix_types.h>
-
-/*
- In Linux 2.1.x the chown functions have been changed. A new function lchown
- was introduced. The new chown now follows symlinks - the old chown and the
- new lchown do not follow symlinks.
- The new lchown function has the same number as the old chown had and the
- new chown has a new number. When compiling with headers from Linux > 2.1.8x
- it's impossible to run this libc with older kernels. In these cases libc
- has therefore to route calls to chown to the old chown function.
-*/
-
-/* Running under Linux > 2.1.80. */
-
-
-#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-/* Compiling for compatibility. */
-int
-attribute_compat_text_section
-__chown_is_lchown (const char *file, uid_t owner, gid_t group)
-{
- return __lchown (file, owner, group);
-}
-#endif
-
-#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-strong_alias (__chown_is_lchown, _chown_is_lchown)
-compat_symbol (libc, __chown_is_lchown, __chown, GLIBC_2_0);
-compat_symbol (libc, _chown_is_lchown, chown, GLIBC_2_0);
-#endif
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list b/sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list
index 3126c60..7a6015a 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list
@@ -1,12 +1,11 @@
# File name Caller Syscall name Args Strong name Weak names
-newchown EXTRA chown32 i:sii __chown chown@@GLIBC_2.1
-lchown - lchown32 i:sii __lchown lchown
+chown - chown32 i:sii __chown chown@@GLIBC_2.1
+lchown - lchown32 i:sii __lchown lchown@@GLIBC_2.0 chown@GLIBC_2.0
fchown - fchown32 i:iii __fchown fchown
oldgetrlimit EXTRA getrlimit i:ip __old_getrlimit getrlimit@GLIBC_2.0
-oldsetrlimit EXTRA setrlimit i:ip __old_setrlimit setrlimit@GLIBC_2.0
-setrlimit - setrlimit i:ip __setrlimit setrlimit@@GLIBC_2.2
+setrlimit - setrlimit i:ip __setrlimit setrlimit@GLIBC_2.0 setrlimit@@GLIBC_2.2
prlimit64 EXTRA prlimit64 i:iipp prlimit64
fanotify_mark EXTRA fanotify_mark i:iiiiis fanotify_mark
--
Joseph S. Myers
joseph@codesourcery.com