The commit
commit 1df872fd74
Author: Florian Weimer <fweimer@redhat.com>
Date: Wed Nov 7 12:42:44 2018 +0100
support: Implement TEST_COMPARE_STRING
added the new macro TEST_COMPARE_STRING, which compares the output of
functions under test against expected strings, and, when there's a
mismatch, automatically reports an error and prints the differences.
This patch adapts recently added test cases to use this new macro.
Tested for powerpc64le (as is, and locally patched to intentionally fail
and produce error output).
* argp/tst-ldbl-argp.c (do_one_test): Use TEST_COMPARE_STRING,
instead of manually comparing and reporting mismatching strings.
* misc/tst-ldbl-error.c (do_one_test): Likewise.
* misc/tst-ldbl-warn.c (do_one_test): Likewise.
Similarly to what has been done for argp_error, and argp_failure, as
well as for warn, warnx, vwarn, and vwarnx, this patch adds new tests
for the following functions: err, errx, verr, verrx, error, and
error_at_line. The new tests check that the conversion of long double
variables into string works correctly on the default format of the type.
Future patches will reuse these tests for other formats that long double
can take.
Tested for powerpc64le.
* misc/Makefile (tests): Add tst-ldbl-error.
* misc/tst-ldbl-error.c: New file.
Similarly to what has been done for argp_error and argp_failure, this
patch patch adds new tests for the warn, warnx, vwarn, and vwarnx
functions. The new tests use the format string to request the
conversion of long double parameters into string. Currently, these
tests only check that the default format of the long double type works.
Future patches will extend the test for platforms that can have an
optional format for long double.
Tested for powerpc64le.
* misc/Makefile (tests): Add tst-ldbl-warn.
* misc/tst-ldbl-warn.c: New file.
Commit 7a16bdbb9f uses IOV_MAX, which is not defined on hurd.
Checked on a build for i686-gnu.
* misc/tst-preadvwritev2-common.c (IOV_MAX): Define if not
defined.
The fallback code of Linux wrapper for preadv2/pwritev2 executes
regardless of the errno code for preadv2, instead of the case where
the syscall is not supported.
This fixes it by calling the fallback code iff errno is ENOSYS. The
patch also adds tests for both invalid file descriptor and invalid
iov_len and vector count.
The only discrepancy between preadv2 and fallback code regarding
error reporting is when an invalid flags are used. The fallback code
bails out earlier with ENOTSUP instead of EINVAL/EBADF when the syscall
is used.
Checked on x86_64-linux-gnu on a 4.4.0 and 4.15.0 kernel.
[BZ #23579]
* misc/tst-preadvwritev2-common.c (do_test_with_invalid_fd): New
test.
* misc/tst-preadvwritev2.c, misc/tst-preadvwritev64v2.c (do_test):
Call do_test_with_invalid_fd.
* sysdeps/unix/sysv/linux/preadv2.c (preadv2): Use fallback code iff
errno is ENOSYS.
* sysdeps/unix/sysv/linux/preadv64v2.c (preadv64v2): Likewise.
* sysdeps/unix/sysv/linux/pwritev2.c (pwritev2): Likewise.
* sysdeps/unix/sysv/linux/pwritev64v2.c (pwritev64v2): Likewise.
Add <bits/indirect-return.h> and include it in <ucontext.h>.
__INDIRECT_RETURN defined in <bits/indirect-return.h> indicates if
swapcontext requires special compiler treatment. The default
__INDIRECT_RETURN is empty.
On x86, when shadow stack is enabled, __INDIRECT_RETURN is defined
with indirect_return attribute, which has been added to GCC 9, to
indicate that swapcontext returns via indirect branch. Otherwise
__INDIRECT_RETURN is defined with returns_twice attribute.
When shadow stack is enabled, remove always_inline attribute from
prepare_test_buffer in string/tst-xbzero-opt.c to avoid:
tst-xbzero-opt.c: In function ‘prepare_test_buffer’:
tst-xbzero-opt.c:105:1: error: function ‘prepare_test_buffer’ can never be inlined because it uses setjmp
prepare_test_buffer (unsigned char *buf)
when indirect_return attribute isn't available.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* bits/indirect-return.h: New file.
* misc/sys/cdefs.h (__glibc_has_attribute): New.
* sysdeps/x86/bits/indirect-return.h: Likewise.
* stdlib/Makefile (headers): Add bits/indirect-return.h.
* stdlib/ucontext.h: Include <bits/indirect-return.h>.
(swapcontext): Add __INDIRECT_RETURN.
* string/tst-xbzero-opt.c (ALWAYS_INLINE): New.
(prepare_test_buffer): Use it.
As for sysctl, ustat has been deprecated in favor of {f}statfs. Also
some newer ports which uses generic interface builds a stub version that
returns ENOSYS.
This patch deprecates ustat interface by removing ustat.h related headers,
adding a compatibility symbol, and avoiding new ports to build and provide
the symbol.
Checked on x86_64-linux-gnu and i686-linux-gnu. Also checked with a
check-abi on all affected ABIs.
* NEWS: Add ustat.h deprecation entry.
* bits/ustat.h: Remove file.
* misc/sys/ustat.h: Likewise.
* misc/ustat.h: Likewise.
* sysdeps/unix/sysv/linux/generic/ustat.c: Likewise.
* misc/Makefile (headers): Remove ustat.h and sys/ustat.h.
* misc/ustat.c (__ustat): Rename to __old_ustat and export only in
compatibility mode.
* sysdeps/unix/sysv/linux/ustat.c (__ustat): Likewise.
* sysdeps/unix/sysv/linux/mips/ustat.c: Define DEV_TO_KDEV and use
generic Linux implementation.
Continuing the fixes for linknamespace and localplt test failures with
-Os that arise from functions not being inlined in that case, this
patch fixes such failures for putc_unlocked and fputc_unlocked.
libc_hidden_* are used for both functions, while namespace issues are
addressed by making putc_unlocked a weak alias of hidden
__putc_unlocked, which is called in the one place where namespace
issues arise (and defined as an inline function in include/stdio.h).
Tested for x86_64 (both without -Os to make sure that case continues
to work, and with -Os to make sure all the relevant linknamespace and
localplt test failures are resolved). This completes fixing the -Os
linknamespace failures (at least for x86_64); localplt failures remain
after this patch.
2018-02-19 Joseph Myers <joseph@codesourcery.com>
[BZ #15105]
[BZ #19463]
* libio/fputc_u.c (fputc_unlocked): Use libc_hidden_def.
* libio/putc_u.c (putc_unlocked): Rename to __putc_unlocked and
define as weak alias of __putc_unlocked. Use libc_hidden_weak.
* include/stdio.h [!_ISOMAC] (fputc_unlocked): Use
libc_hidden_proto.
[!_ISOMAC] (putc_unlocked): Likewise.
[!_ISOMAC] (__putc_unlocked): Declare as hidden function, and
define inline if [__USE_EXTERN_INLINES].
* misc/syslog.c (__vsyslog_chk): Call __putc_unlocked instead of
putc_unlocked.
Continuing the fixes for linknamespace and localplt test failures with
-Os that arise from functions not being inlined in that case, this
patch fixes such failures for getc_unlocked.
__getc_unlocked already exists; this patch makes it explicitly hidden,
calls it where needed for namespace reasons, adds an inline function
for it when inline functions are used and adds libc_hidden_proto /
libc_hidden_weak for getc_unlocked.
Tested for x86_64 (both without -Os to make sure that case continues
to work, and with -Os to make sure all the relevant linknamespace and
localplt test failures are resolved). Because of other such failures
that remain after this patch, neither of the bugs can yet be closed.
[BZ #15105]
[BZ #19463]
* libio/getc_u.c (getc_unlocked): Use libc_hidden_weak.
* include/stdio.h [!_ISOMAC] (__getc_unlocked): Use
attribute_hidden, and define inline if [__USE_EXTERN_INLINES].
[!_ISOMAC] (getc_unlocked): Use libc_hidden_proto.
* misc/getttyent.c (__getttyent): Call __getc_unlocked instead of
getc_unlocked.
* time/tzfile.c (__tzfile_read): Likewise.
This completes the deprecation and removal of this inclusion, which
was begun in the 2.25 release.
* posix/sys/types.h: Don't include sys/sysmacros.h.
* misc/sys/sysmacros.h: Remove the conditional deprecation
warnings for the macros defined by this header.
Building with -Os produces linknamespace and localplt failures for,
among other functions, gnu_dev_major, gnu_dev_minor and
gnu_dev_makedev.
The issue is that those functions are not inlined when building with
-Os. While one could force them to be inlined in that case, it seems
more natural to fix this issue similarly to other namespace issues.
Thus, this patch makes gnu_dev_* into weak aliases for hidden symbols
__gnu_dev_*; __gnu_dev_* are then defined as inlines in the internal
include/sys/sysmacros.h, and uses of gnu_dev_* (often via the macros
major, minor and makedev) for which there are namespace issues are
changed to use __gnu_dev_*; where there are no namespace issues, use
of libc_hidden_proto serves to avoid unnecessary local PLT entry use.
Tested for x86_64, (a) without -Os, to verify the testsuite continues
to pass without problems and that the functions called under their new
names continue to be inlined as expected in that case; (b) with -Os,
to verify that the linknamespace and localplt failures in question go
away (but because of other such failures present, neither of the
relevant bugs can yet be closed).
[BZ #15105]
[BZ #19463]
* include/sys/sysmacros.h [!_ISOMAC]
(__SYSMACROS_NEED_IMPLEMENTATION): Define macro.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC]
(_SYS_SYSMACROS_H_WRAPPER): Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (gnu_dev_major): Use
libc_hidden_proto.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (gnu_dev_minor): Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (gnu_dev_makedev):
Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__SYSMACROS_DECL_TEMPL):
Undefine and redefine to add use __gnu_dev_ prefix.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__SYSMACROS_IMPL_TEMPL):
Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__gnu_dev_major): Declare
and define as hidden inline function.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__gnu_dev_minor):
Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__gnu_dev_makedev):
Likewise.
* misc/makedev.c (OUT_OF_LINE_IMPL_TEMPL): Use __gnu_dev_ prefix.
(gnu_dev_major): Use weak_alias and libc_hidden_weak.
(gnu_dev_minor): Likewise.
(gnu_dev_makedev): Likewise.
* csu/check_fds.c (check_one_fd): Use __gnu_dev_makedev instead of
makedev.
* posix/wordexp.c (exec_comm_child): Likewise.
* sysdeps/mach/hurd/xmknodat.c (__xmknodat): Use __gnu_dev_minor
instead of minor and __gnu_dev_major instead of major.
* sysdeps/unix/sysv/linux/device-nrs.h (DEV_TTY_P): Use
__gnu_dev_major instead of major.
* sysdeps/unix/sysv/linux/pathconf.c (distinguish_extX): Use
__gnu_dev_major instead of gnu_dev_major and __gnu_dev_minor
instead of gnu_dev_minor.
* sysdeps/unix/sysv/linux/ptsname.c (MASTER_P): Likewise.
(SLAVE_P): Likewise.
(__ptsname_internal): Use __gnu_dev_minor instead of minor.
* sysdeps/unix/sysv/linux/ttyname.h (is_pty): Use __gnu_dev_major
instead of major.
Bug 17721 reports that the non-__GNUC__ definitions of __inline and
__restrict are suboptimal, in that they are defined to empty when they
could be defined to inline and restrict for appropriate language
versions. This patch makes those fixes.
Tested for x86_64 (however, I have not done any testing with an actual
non-__GNUC__ compiler and it's likely such compilers may have other
problems with glibc headers).
[BZ #17721]
* misc/sys/cdefs.h [!__GNUC__ && (__cplusplus || (__STDC_VERSION__
&& __STDC_VERSION__ >= 199901L))] (__inline): Define to inline.
[!__GNUC_PREREQ (2,92) && __STDC_VERSION__ && __STDC_VERSION__ >=
199901L] (__restrict): Define to restrict.
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
Hide internal __hasmntopt function to allow direct access within libc.so
and libc.a without using GOT nor PLT.
[BZ #18822]
* include/mntent.h (__hasmntopt): Add libc_hidden_proto.
* misc/mntent_r.c (__hasmntopt): Add libc_hidden_def.
Hide internal __tdestroy function to allow direct access within libc.so
and libc.a without using GOT nor PLT.
[BZ #18822]
* include/search.h (__tdestroy): Add libc_hidden_proto.
* misc/tsearch.c (__tdestroy): Add libc_hidden_def.
Hide internal __ioctl function to allow direct access within libc.so and
libc.a without using GOT nor PLT.
__GI___ioctl is defined when sysdeps/unix/syscalls.list is used to
generate ioctl. Otherwise libc_hidden_def is needed explicitly.
[BZ #18822]
* include/sys/ioctl.h (__ioctl): Add libc_hidden_proto.
* misc/ioctl.c (__ioctl): Add libc_hidden_def.
* sysdeps/mach/hurd/ioctl.c (__ioctl): Likewise.
* sysdeps/unix/sysv/linux/aarch64/ioctl.S (__ioctl): Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/ioctl.S (__ioctl):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/ioctl.c (__ioctl): Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/ioctl.S (__ioctl): Likewise.
`revoke' is MISC only, it should not be exposed along `unlockpt' which is
XOPEN.
* include/unistd.h (__revoke): New declaration.
* misc/revoke.c (revoke): Rename to __revoke, and redefine as weak
alias.
* sysdeps/mach/hurd/revoke.c (revoke): Likewise.
* sysdeps/unix/bsd/unlockpt.c (unlockpt): Use __revoke instead of
revoke.
* misc/tst-preadvwritev2-common.c (RWF_HIPRI, RWF_DSYNC, RWF_SYNC,
RWF_NOWAIT): Define to 0 if undefined already.
(do_test_with_invalid_flags): Set invalid_flag to 2 if RWF_SUPPORTED
boils down to 0.
* misc/preadv2.c: Include <errno.h>.
* misc/preadv64v2.c: Include <errno.h>.
* misc/pwritev2.c: Include <errno.h>.
* misc/pwritev64v2.c: Include <errno.h>.
* sysdeps/posix/preadv2.c: Include <errno.h>.
* sysdeps/posix/preadv64v2.c: Include <errno.h>.
Fix <unistd.h> inclusion.
* sysdeps/posix/pwritev2.c: Include <errno.h>.
* sysdeps/posix/pwritev64v2.c: Include <errno.h>.
Since __libc_multiple_libcs is defined as hidden symbol in init-first.c,
it should be always marked with attribute_hidden.
[BZ #18822]
* csu/libc-start.c (__libc_multiple_libcs): Removed.
* elf/dl-open.c: Include <libc-internal.h>.
(__libc_multiple_libcs): Removed.
* elf/dl-sysdep.c: Include <libc-internal.h> instead of
<hp-timing.h>.
* include/libc-internal.h (__libc_multiple_libcs): New.
* misc/sbrk.c: Include <libc-internal.h>.
(__libc_multiple_libcs): Removed.
The logic to protect the use of generic selection (_Generic) does not
check for C or C++ mode, however, generic selection is a C-only
feature.
Tested for powerpc64le.
* misc/sys/cdefs.h (__HAVE_GENERIC_SELECTION): Define to 0, if
in C++ mode.
sys/cdefs.h has a macro __long_double_t used in two places in glibc.
long double is a standard part of C since C89; there is no need for
such an alias for it. This patch removes that macro and uses long
double directly everywhere. As an implementation-namespace,
undocumented symbol, it should not be considered part of the API for
users, and codesearch.debian.net shows no sign of it being used
outside glibc in a way that would break with this patch.
Tested for x86_64.
* misc/sys/cdefs.h (__long_double_t): Remove.
* stdio-common/printf_fp.c (__printf_fp_l): Use long double
instead of __long_double_t,
* stdlib/strfmon_l.c (__vstrfmon_l): Likewise.
Linux 4.12 (b745fafaf70c0a98a2e1e7ac8cb14542889ceb0e) adds a new
p{read,write}v2 flag RWF_NOWAIT. This patch adds it for linux
uio-ext.h header.
Checked on x86_64-linux-gnu (on a 4.10 kernel).
[BZ #21738]
* manual/llio.texi (RWF_NOWAIT): New item.
* misc/tst-preadvwritev2-common.c (do_test_with_invalid_flags):
Add RWF_NOWAIT check.
* sysdeps/unix/sysv/linux/bits/uio-ext.h (RWF_NOWAIT): New flag.
This patch increases the timeouts for some tests that I've seen timing
out on slow systems in my 2.26 release testing. (In the case of
tst-tsearch.c, increasing the timeout means removing a setting of 10
that was put there before the default timeout was increased to 20
seconds, so putting the default into effect.)
* iconvdata/tst-loading.c (TIMEOUT): Define to 30.
* misc/tst-tsearch.c (TIMEOUT): Remove.
* nptl/tst-create-detached.c (TIMEOUT): Define to 100.
* nptl/tst-robust-fork.c (TIMEOUT): Likewise.
* nptl/tst-rwlock19.c (TIMEOUT): Likewise.
* string/tst-cmp.c (TIMEOUT): Define to 600.
The .symver directive on common symbol just creates a new common symbol,
not an alias and the newer assembler with the bug fix for
https://sourceware.org/bugzilla/show_bug.cgi?id=21661
will issue an error. Before the fix, we got
$ readelf -sW libc.so | grep "loc[12s]"
5109: 00000000003a0608 8 OBJECT LOCAL DEFAULT 36 loc1
5188: 00000000003a0610 8 OBJECT LOCAL DEFAULT 36 loc2
5455: 00000000003a0618 8 OBJECT LOCAL DEFAULT 36 locs
6575: 00000000003a05f0 8 OBJECT GLOBAL DEFAULT 36 locs@GLIBC_2.2.5
7156: 00000000003a05f8 8 OBJECT GLOBAL DEFAULT 36 loc1@GLIBC_2.2.5
7312: 00000000003a0600 8 OBJECT GLOBAL DEFAULT 36 loc2@GLIBC_2.2.5
in libc.so. The versioned loc1, loc2 and locs have the wrong addresses.
After the fix, we got
$ readelf -sW libc.so | grep "loc[12s]"
6570: 000000000039e3b8 8 OBJECT GLOBAL DEFAULT 34 locs@GLIBC_2.2.5
7151: 000000000039e3c8 8 OBJECT GLOBAL DEFAULT 34 loc1@GLIBC_2.2.5
7307: 000000000039e3c0 8 OBJECT GLOBAL DEFAULT 34 loc2@GLIBC_2.2.5
[BZ #21666]
* misc/regexp.c (loc1): Add __attribute__ ((nocommon));
(loc2): Likewise.
(locs): Likewise.
This patch add an extra test for passing invalid flags and check its
expected failure. It shows an invalid LO_HI_LONG macro definition for
x86_64 with leads to passing invalid flags on some configurations.
The new tests fails on i686-linux-gnu and potentially on other 32 bits
architecture that uses the compat syscall definition due a kernel bug.
It is intended to be fixed upstream.
Checked on x86_64-linux-gnu
* misc/tst-preadvwritev2-common.c: New file.
* misc/tst-preadvwritev2.c (do_test): Add test for invalid flag.
* misc/tst-preadvwritev64v2.c (do_test): Likewise.
__need_FOPEN_MAX wasn't being used anywhere. __need_IOV_MAX was more
complicated; the basic deal is that sys/uio.h wants to define a
constant named UIO_MAXIOV and bits/xopen_lim.h wants to define a
constant named IOV_MAX, with the same meaning. For no apparent reason
this was being handled via bits/stdio_lim.h -- stdio.h is NOT supposed
to define IOV_MAX -- and some mess in Makerules. Also, bits/uio.h on
Linux was being used as a dumping ground for extension functions.
So now we have bits/uio_lim.h, which defines __IOV_MAX.
bits/xopen_lim.h and sys/uio.h use that to define their respective
constants. We also now have bits/uio-ext.h, which is the official
Proper Home for extensions to sys/uio.h. bits/uio.h is removed, and
stdio_lim.h doesn't define IOV_MAX at all.
* bits/uio_lim.h, sysdeps/unix/sysv/linux/bits/uio_lim.h
* bits/uio-ext.h, sysdeps/unix/sysv/linux/bits/uio-ext.h: New file.
* bits/uio.h, sysdeps/unix/sysv/linux/bits/uio.h: Delete file.
* include/bits/xopen_lim.h: Use bits/uio_lim.h to get the value
for IOV_MAX.
* misc/Makefile: Install bits/uio-ext.h and bits/uio_lim.h.
Don't install bits/uio.h.
* misc/sys/uio.h: Don't include bits/uio.h. Do include
bits/types/struct_iovec.h and bits/uio_lim.h. Set UIO_MAXIOV
based on __IOV_MAX. Under __USE_GNU, also include bits/uio-ext.h.
* stdio-common/stdio_lim.h.in: Remove logic for __need_FOPEN_MAX
and __need_IOV_MAX. Don't define IOV_MAX at all.
* Makerules (stdio_lim.h): Remove logic for setting IOV_MAX.
* sysdeps/unix/sysv/linux/bits/fcntl-linux.h:
Include bits/types/struct_iovec.h, not bits/uio.h.
Use __ssize_t, not ssize_t, in function prototypes.
Don't use hard TAB for double space after period in comments.
wint_t is a little finicky because it might be defined by stddef.h, which
belongs to the compiler.
In addition to the _types_, a bunch of other declarations shared between
wctype.h and wchar.h are factored out to their own header.
* libio/bits/types/FILE.h, libio/bits/types/__FILE.h
* wcsmbs/bits/types/mbstate_t.h, wcsmbs/bits/types/__mbstate_t.h
* wcsmbs/bits/types/wint_t.h: New single-type definition files.
* wctype/bits/wctype-wchar.h: New file holding declarations shared
between wctype.h and wchar.h.
* libio/Makefile, wcsmbs/Makefile, wctype/Makefile:
Install them.
* include/bits/types/FILE.h, include/bits/types/__FILE.h
* include/bits/types/mbstate_t.h, include/bits/types/__mbstate_t.h
* include/bits/types/wint_t.h, include/bits/wcsmbs-wchar.h:
New wrappers.
* include/stdio.h, include/wchar.h, include/wctype.h:
No need to handle __need macros.
* grp/grp.h, gshadow/gshadow.h, hurd/hurd.h, iconv/gconv.h
* libio/stdio.h, mach/mach.h, misc/mntent.h, pwd/pwd.h
* shadow/shadow.h, stdio-common/printf.h, wcsmbs/uchar.h
* wcsmbs/wchar.h, wctype/wctype.h
* sysdeps/generic/_G_config.h, sysdeps/unix/sysv/linux/_G_config.h
Use the new files instead of __need macros.
This patch adds the missing compiler flags for correct pthread cancellation
on some architectures for the p{read,write}v2 implementation (52bd938169).
Checked on x86_64-linux-gnu and powerpc64le-linux-gnu.
* misc/Makefile (CFLAGS-preadv2.c): New rule.
(CFLAGS-preadv64v2.c): Likewise.
(CFLAGS-pwritev2.c): Likewise.
(CFLAGS-pwritev64v2.c): Likewise.
This patch adds support of preadv2 and pwritev2 which are similar to
preadv/pwritev but with an extra flag argument. As for preadv/pwritev
both interfaces are added a non-standard GNU API.
For default 'posix' implementation trying to emulate the Linux supported
flags is troublesome:
* We can not temporary change the file state of the O_DSYNC and O_SYNC
flags to emulate RWF_{D}SYNC (attempts to change the state of using
fcntl are silently ignored).
* IOCB_HIPRI requires the file opened in O_DIRECT and uses an internal
semantic not provided by any other flag (O_NONBLOCK for instance).
So default sysdeps/posix implementations fails with EOPNOTSUPP for any non
supported flag (which are none currently) calls generic preadv/pwritev.
Basically this implementation supports only preadv2 called as preadv (with
flags sets to 0).
The Linux one uses the preadv2/pwritev2 syscall if defined, otherwise it
call preadv/writev. Instead of using the previous __ASSUME_* to
unconditionally issue the syscall (and avoid building the fallback routine),
it call pread/write if the preadv2/pwritev2 syscalls fails. The idea
is just avoid adding another __ASSUME_* and checking each architecture
on every kernel bump and simplify code conditionals.
Checked on x86_64-linux-gnu and on i686-linux-gnu and a check with
run-built-tests=no on aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabihf,
ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu, mips{64,64n32}-linux-gnu,
nios2-linux-gnu, powerpc{64,64le}-linux-gnu, s390{x}-linux-gnu,
sparc{64,v9}-linux-gnu, tile{gx,pro}-linux-gnu, and sh4-linux-gnu (all using
gcc 6.3).
* NEWS: Add note about pwritev2 and preadv2 inclusion.
* misc/Makefile (routines): Add preadv2, preadv64v2, pwritev2, and
pwritev64v2.
(tests): Add tst-preadvwritev2 and tst-preadvwritev64v2.
* misc/Versions (GLIBC_2.26): Add preadv2, preadv64v2, pwritev2, and
pwritev64v2.
* misc/preadv2.c: New file.
* misc/preadv64v2.c: Likewise.
* misc/pwritev2.c: Likewise.
* misc/pwritev64v2.c: Likewise.
* misc/tst-preadvwritev2.c: Likewise.
* misc/tst-preadvwritev64v2.c: Likewise.
* manual/llio.texi: Add preadv2 and pwritev2 documentation.
* misc/sys/uio.h [__USE_GNU && !__USE_FILE_OFFSET64] (preadv2): New
prototype.
[__USE_GNU && !__USE_FILE_OFFSET64] (pwritev2): Likewise.
[__USE_GNU && __USE_FILE_OFFSET64] (preadv64v2): Likewise.
[__USE_GNU && __USE_FILE_OFFSET64] (pwritev64v2): Likewise.
* misc/tst-preadvwritev-common.c (PREADV): Define if not defined.
(PWRITEV): Likewise.
(do_test_with_offset): Use PREADV and PWRITEV macros and check for
ENOSYS.
* nptl/tst-cancel4.c (tf_pwritev2): New test.
(tf_preadv2): Likewise.
(tf_fsync): Add tf_pwritev2 and tf_preadv2.
* sysdeps/posix/preadv2.c: Likewise.
* sysdeps/posix/preadv64v2.c: Likewise.
* sysdeps/posix/pwritev2.c: Likewise.
* sysdeps/posix/pwritev64v2.c: Likewise.
* sysdeps/unix/sysv/linux/kernel-features.h: Add comment for syscall
support in kernel.
* sysdeps/unix/sysv/linux/preadv2.c: Likewise.
* sysdeps/unix/sysv/linux/preadv64v2.c: Likewise.
* sysdeps/unix/sysv/linux/pwritev2.c: Likewise.
* sysdeps/unix/sysv/linux/pwritev64v2.c: Likewise.
* sysdeps/unix/sysv/linux/preadv.c (preadv): Add libc_hidden_def.
* sysdeps/unix/sysv/linux/preadv64.c (preadv64): Likewise.
* sysdeps/unix/sysv/linux/pwritev.c (pwritev): Likewise.
* sysdeps/unix/sysv/linux/pwritev64.c (pwritev64): Likewise.
* sysdeps/unix/sysv/linux/bits/uio.h: Add supported preadv2/pwritev2
support flags on Linux.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist (GLIBC_2.26): Add
preadv2, preadv64v2, pwritev2, pwritev64v2.
* sysdeps/unix/sysv/linux/alpha/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/arm/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/hppa/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/microblaze/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/nios2/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
(GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
(GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist
(GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/sh/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/sysv/linux/tile/tilegx/tilegx32/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/sysv/linux/tile/tilegx/tilegx64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist (GLIBC_2.26):
Likewise.
