glibc/ports
Joseph Myers 0e31b18ca2 Fix __ASSUME_RECVMMSG issues (bug 16610).
Similar to the issues for accept4, __ASSUME_RECVMMSG is also confused
about whether it relates to function availability or socketcall
operation availability; this is now bug 16610.

Nothing actually tests __ASSUME_RECVMMSG for function availability,
but implicit in the definition in kernel-features.h is the idea that
it makes sense when the syscall is available and socketcall is not
being used.  As with accept4, there are architectures where the
syscall was added later than the socketcall operation, meaning that
assuming glibc is built with recent enough kernel headers, it does not
attempt to use socketcall for these operations and __ASSUME_RECVMMSG
gets defined for kernels >= 2.6.33 even when the syscall was only
added later.

This patch splits the macro into separate macros like those used for
accept4; having similar macro structure in both cases (and for
sendmmsg once I've dealt with that) seems likely to be less confusing
than having a different structure on the basis of nothing actually
needing to assume the recvmmsg function works.  Appropriate
definitions are added for all architectures.

Architecture-specific note: Tile's kernel-features.h says "TILE glibc
support starts with 2.6.36", which is accurate in that 2.6.36 was the
first kernel version with Tile support, and on that basis I've made
that header define __ASSUME_RECVMMSG_SYSCALL unconditionally.
However, Tile's configure.ac has arch_minimum_kernel=2.6.32.  Since
arch_minimum_kernel is meant to reflect only kernel.org kernel
versions, I think that should change to 2.6.36.  (If using glibc with
kernel versions from before a port went in kernel.org, it's your
responsibility to change arch_minimum_kernel in a local patch, and at
the same time to adjust any __ASSUME_* definitions that may not be
correct for your older kernel; for developing the official glibc it
should only ever be necessary to consider what official kernel.org
releases support.)

Tested x86_64, including that disassembly of the installed shared
libraries is unchanged by this patch.

	[BZ #16610]
	* sysdeps/unix/sysv/linux/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020621 && __ASSUME_SOCKETCALL]
	(__ASSUME_RECVMMSG_SOCKETCALL): Define.
	[(__LINUX_KERNEL_VERSION >= 0x020621 && (__i386__ || __x86_64__ ||
	__sparc__)) || (__LINUX_KERNEL_VERSION >= 0x020625 && (__powerpc__
	|| __sh__))] (__ASSUME_RECVMMSG_SYSCALL): Likewise.
	[__i386__ || __sparc__]
	(__ASSUME_RECVMMSG_SYSCALL_WITH_SOCKETCALL): Likewise.
	[__ASSUME_RECVMMSG_SOCKETCALL || __ASSUME_RECVMMSG_SYSCALL]
	(__ASSUME_RECVMMSG): Define instead of using previous
	[__LINUX_KERNEL_VERSION >= 0x020621] condition.
	* sysdeps/unix/sysv/linux/aarch64/kernel-features.h
	(__ASSUME_RECVMMSG_SYSCALL): Define.
	* sysdeps/unix/sysv/linux/alpha/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG_SYSCALL):
	Likewise.
	* sysdeps/unix/sysv/linux/arm/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG_SYSCALL):
	Likewise.
	* sysdeps/unix/sysv/linux/ia64/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG_SYSCALL):
	Likewise.
	* sysdeps/unix/sysv/linux/internal_recvmmsg.S [__ASSUME_SOCKETCALL
	&& !__ASSUME_RECVMMSG_SYSCALL_WITH_SOCKETCALL &&
	!__ASSUME_RECVMMSG_SYSCALL] (__NR_recvmmsg): Undefine.
	[__ASSUME_RECVMMSG]: Change condition to
	[__ASSUME_RECVMMSG_SOCKETCALL].
	* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG_SYSCALL):
	Define.
	(__ASSUME_RECVMMSG_SYSCALL_WITH_SOCKETCALL): Likewise.
	* sysdeps/unix/sysv/linux/mips/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_RECVMMSG_SYSCALL):
	Likewise.
	* sysdeps/unix/sysv/linux/recvmmsg.c [__ASSUME_SOCKETCALL &&
	!__ASSUME_RECVMMSG_SYSCALL_WITH_SOCKETCALL &&
	!__ASSUME_RECVMMSG_SYSCALL] (__NR_recvmmsg): Undefine.
	[!__ASSUME_RECVMMSG]: Change condition to
	[!__ASSUME_RECVMMSG_SOCKETCALL].
	* sysdeps/unix/sysv/linux/tile/kernel-features.h
	(__ASSUME_RECVMMSG_SYSCALL): Define.

	* sysdeps/unix/sysv/linux/hppa/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020622] (__ASSUME_RECVMMSG_SYSCALL):
	Define.
2014-02-20 17:53:08 +00:00
..
sysdeps Fix __ASSUME_RECVMMSG issues (bug 16610). 2014-02-20 17:53:08 +00:00
ChangeLog rename configure.in to configure.ac 2013-10-30 17:32:08 +10:00
ChangeLog.aarch64 Relocate AArch64 from ports to libc. 2014-02-11 11:36:00 +00:00
ChangeLog.aix Move all files into ports/ subdirectory in preparation for merge with glibc 2012-07-01 13:06:41 +00:00
ChangeLog.alpha ia64: relocate out of ports/ subdir 2014-02-16 01:12:38 -05:00
ChangeLog.am33 Remove am33 port. 2014-02-08 00:16:57 +00:00
ChangeLog.arm Move arm from ports to libc. 2014-02-08 01:49:39 +00:00
ChangeLog.cris Move all files into ports/ subdirectory in preparation for merge with glibc 2012-07-01 13:06:41 +00:00
ChangeLog.hppa Fix __ASSUME_RECVMMSG issues (bug 16610). 2014-02-20 17:53:08 +00:00
ChangeLog.ia64 ia64: relocate out of ports/ subdir 2014-02-16 01:12:38 -05:00
ChangeLog.linux-generic Move tilegx, tilepro, and linux-generic from ports to libc. 2014-02-10 11:04:39 -05:00
ChangeLog.m68k Move m68k from ports to libc 2014-02-10 20:22:40 +01:00
ChangeLog.microblaze [MicroBlaze]: Move MicroBlaze from ports to sysdeps. 2014-02-17 11:08:21 +10:00
ChangeLog.mips ia64: relocate out of ports/ subdir 2014-02-16 01:12:38 -05:00
ChangeLog.powerpc Move powerpc ports pieces to libc. 2013-10-04 16:02:33 +00:00
ChangeLog.tile Move tilegx, tilepro, and linux-generic from ports to libc. 2014-02-10 11:04:39 -05:00
README rename configure.in to configure.ac 2013-10-30 17:32:08 +10:00

This is the glibc ports add-on, an add-on for the GNU C Library (glibc).
It contains code that is not maintained in the official glibc source tree.

This includes working ports to GNU/Linux on some machine architectures that
are not maintained in the official glibc source tree.  It also includes
some code once used by old libc ports now defunct, which has been abandoned
but may be useful for some future porter to examine.  It may also include
some optimized functions tailored for specific CPU implementations of an
architecture, to be selected using --with-cpu.

The ports add-on is cooperatively maintained by volunteers on the
<libc-ports@sourceware.org> mailing list, and housed in the ports
subdirectory of the glibc git repository.  See
http://www.gnu.org/software/libc/download.html for details on using
git.  To report a bug in code housed in the ports add-on, please go to
http://sourceware.org/bugzilla/ and file a bug report under the glibc
"ports" component.

An add-on for an individual port can be made from just the sysdeps/
subdirectories containing the port's code.  You may want to include a
README and Banner of your own talking about your port's code in particular,
rather than the generic ones here.

The real source code for any ports is found in the sysdeps/ subdirectories.
These should be exactly what would go into the main libc source tree if you
were to incorporate it directly.  The only exceptions are the files
sysdeps/*/preconfigure and sysdeps/*/preconfigure.ac; these are fragments
used by this add-on's configure fragment.  The purpose of these is to set
$base_machine et al when the main libc configure's defaults are not right
for some machine.  Everything else can and should be done from a normal
sysdeps/.../configure fragment that is used only when the configuration
selects that sysdeps subdirectory.  Each port that requires some special
treatment before the sysdeps directory list is calculated, should add a
sysdeps/CPU/preconfigure file; this can either be written by hand or
generated by Autoconf from sysdeps/CPU/preconfigure.ac, and follow the
rules for glibc add-on configure fragments.  No preconfigure file should do
anything on an unrelated configuration, so that disparate ports can be put
into a single add-on without interfering with each other.

Like all glibc add-ons, this must be used by specifying the directory in
the --enable-add-ons option when running glibc's configure script.

The GNU C Library is free software.  See the file COPYING.LIB in the
libc repository for copying conditions, and LICENSES for notices about
a few contributions that require these additional notices to be
distributed.  License copyright years may be listed using range
notation, e.g., 2000-2013, indicating that every year in the range,
inclusive, is a copyrightable year that would otherwise be listed
individually.