This patch 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.
* sysdeps/unix/make-syscalls.sh (emit_weak_aliases): Condition
compat_symbol calls on [SHARED].
* sysdeps/unix/sysv/linux/powerpc/lchown.S: Remove file.
* sysdeps/unix/sysv/linux/i386/syscalls.list (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
(oldsetrlimit): Remove.
(setrlimit): Add setrlimit@GLIBC_2.0 alias.
Bug 14138 is followup cleanup after removal of support for old Linux
kernel versions: moving syscalls to syscalls.list where the only
reason for using C definitions was kernel version conditionals that
are no longer present.
This patch deals with the case of setrlimit
(sysdeps/unix/sysv/linux/i386/setrlimit.c, included by various other
architectures). Where needed (where there is also a compat symbol for
setrlimit@GLIBC_2.0), new syscalls.list entries are added. Where not
needed (where there is no such compat symbol and the minimum symbol
version for libc is 2.2 or later), no such entries are added as that
in sysdeps/unix/syscalls.list will suffice. Thus arm and sh need no
such entries, while m68k and powerpc need entries only in a
subdirectory syscalls.list file rather than for all configurations
that previously used setrlimit.c.
(setrlimit@@GLIBC_2.2 and setrlimit@GLIBC_2.0 are now semantically
identical - the new symbol version was about a change of types from
signed to unsigned and the former compatibility code for dealing with
large unsigned arguments on old kernels is no longer needed or
present, having been removed with support for pre-2.4 kernels.
However, making the two versions into aliases doesn't work at present:
the case of having both default and non-default symbol versions on the
same syscalls.list line results in a compat_symbol call in code built
for static libc, which doesn't compile. I don't suppose it would be
hard to generate SHARED conditionals from make-syscalls.sh to fix
this, but in any case this patch doesn't make things any worse, as the
functions weren't aliases before the patch either.)
Tested for x86, and ran ABI tests for ARM as an example of an
architecture where the setrlimit.c file was just removed without
adding syscalls.list entries.
[BZ #14138]
* sysdeps/unix/sysv/linux/arm/setrlimit.c: Remove file.
* sysdeps/unix/sysv/linux/i386/setrlimit.c: Likewise.
* sysdeps/unix/sysv/linux/m68k/setrlimit.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/setrlimit.c: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/setrlimit.c: Likewise.
* sysdeps/unix/sysv/linux/sh/setrlimit.c: Likewise.
* sysdeps/unix/sysv/linux/i386/syscalls.list (setrlimit): Add
syscall entry for GLIBC_2.2 symbol version.
* sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list (setrlimit):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
(setrlimit): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list (setrlimit):
Likewise.
