As for gettimeofday, time will be implemented based on clock_gettime
on all platforms and internal code should use clock_gettime
directly. In addition to removing a layer of indirection, this will
allow us to remove the PLT-bypass gunk for gettimeofday.
The changed code always assumes __clock_gettime (CLOCK_REALTIME)
or __clock_gettime (CLOCK_REALTIME_COARSE) (for Linux case) cannot
fail, using the same rationale for gettimeofday change. And internal
helper was added (time_now).
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, and powerpc-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Historically autofs mounts were not included in mount table
listings. This is the case in other SysV autofs implementations
and was also the case with Linux autofs.
But now that /etc/mtab is a symlink to the proc filesystem
mount table the autofs mount entries appear in the mount table
on Linux.
Prior to the symlinking of /etc/mtab mount table it was
sufficient to call mount(2) and simply not update /etc/mtab
to exclude autofs mounts from mount listings.
Also, with the symlinking of /etc/mtab we have seen a shift in
usage toward using the proc mount tables directly.
But the autofs mount entries need to be retained when coming
from the proc file system for applications that need them
(largely autofs file system users themselves) so filtering out
these entries within the kernel itself can't be done. So it
needs be done in user space.
There are three reasons to omit the autofs mount entries.
One is that certain types of auto-mounts have an autofs mount
for every entry in their autofs mount map and these maps can
be quite large. This leads to mount table listings containing
a lot of unnecessary entries.
Also, this change in behaviour between autofs implementations
can cause problems for applications that use getmntent(3) in
other OS implementations as well as Linux.
Lastly, there's very little that user space can do with autofs
mount entries since this must be left to the autofs mount owner,
typically the automount daemon. But it can also lead to attempts
to access automount managed paths resulting mounts being triggered
when they aren't needed or mounts staying mounted for much longer
thay they need be. While the point of this change ins't to help
with these problems (and it can be quite a problem) it may be
a welcome side effect.
So the Linux autofs file system has been modified to accept a
pseudo mount option of "ignore" (as is used in other OS
implementations) so that user space can use this as a hint to
skip autofs entries on reading the mount table.
The Linux autofs automount daemon used getmntent(3) itself and
has been modified to use the proc file system directly so that
it can "ignore" mount option.
The use of this mount option is opt-in and a configuration
option has been added which defaults to not use this option
so if there are applications that need these entries, other
than autofs itself, they can be retained. Also, since this
filtering is based on an added mount option earlier versions
of Linux autofs iand other autofs file system users will not
use the option and so won't be affected by the change.
Both the buffer and struct mntent are now allocated on the heap.
This results in a slight reduction of RSS usage.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
It doesn't make sense to remove all the internal uses of time.
It's still a standard ISO C function, and its callers don't need
sub-second resolution and would be unnecessarily complicated if
they had to declare a struct timespec instead of just a time_t.
However, a handful of places were using the vestigial "result"
argument instead of the return value, which is slightly less
efficient and also looks strange. Correct this.
* misc/syslog.c (__vsyslog_internal)
* time/getdate.c (__getdate_r)
* time/tst_wcsftime.c (main):
Use return value of time, not its argument.
* string/strfry.c (strfry)
* sysdeps/mach/sleep.c (__sleep):
Remove unnecessary casts of NULL in calls to time.
This is currently ineffective with GCC because of GCC PR 80005, but
it makes sense to anticipate a fix for this defect.
Suggested by Zack Weinberg.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The twalk function is very difficult to use in a multi-threaded
program because there is no way to pass external state to the
iterator function.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch adds test cases for the compatibility versions of the
functions: err, errx, verr, verrx, warn, warnx, vwarn, vwarnx (from
err.h), error, and error_at_line (from error.h), when long double has
the same format as double (-mlong-double-64).
Tested for powerpc, powerpc64 and powerpc64le.
On platforms where long double may have the same format as double
(-mlong-double-64), error and error_at_line do not take that into
account and might produce wrong output if a long double conversion is
requested by the format string ('%Lf'). This patch adds compatibility
functions for this situation and redirects calls via header magic.
Tested for powerpc, powerpc64 and powerpc64le.
When support for long double format with 128-bits (-mlong-double-128)
was added for platforms where long double had the same format as double,
such as powerpc, compatibility versions for the functions listed in the
commit title were missed. Since the older format of long double can
still be used (with -mlong-double-64), using these functions with a
format string that requests the printing of long double variables will
produce wrong outputs.
This patch adds the missing compatibility functions and header magic to
redirect calls to them when -mlong-double-64 is in use.
Tested for powerpc, powerpc64 and powerpc64le.
Since the introduction of explicit flags in the internal implementation
of the printf family of functions, the 'mode' parameter can be used to
select which format long double parameters have (with the mode flag:
PRINTF_LDBL_IS_DBL). This patch uses this feature in the implementation
of some functions in argp.h, err.h, and error.h (only those that take a
format string and positional parameters). Future patches will add
support for 'nldbl' and 'ieee128' versions of these functions.
Tested for powerpc64le and x86_64.
This patch adds fall-through comments in some cases where -Wextra
produces implicit-fallthrough warnings.
The patch is non-exhaustive. Apart from architecture-specific code
for non-x86_64 architectures, it does not change sunrpc/xdr.c (legacy
code, probably should have such changes, but left to be dealt with
separately), or places that already had comments about the
fall-through but not matching the form expected by
-Wimplicit-fallthrough=3 (the default level with -Wextra; my
inclination is to adjust those comments to match rather than
downgrading to -Wimplicit-fallthrough=1 to allow any comment), or one
place where I thought the implicit fallthrough was not correct and so
should be handled separately as a bug fix. I think the key thing to
consider in review of this patch is whether the fall-through is indeed
intended and correct in each place where such a comment is added.
Tested for x86_64.
* elf/dl-exception.c (_dl_exception_create_format): Add
fall-through comments.
* elf/ldconfig.c (parse_conf_include): Likewise.
* elf/rtld.c (print_statistics): Likewise.
* locale/programs/charmap.c (parse_charmap): Likewise.
* misc/mntent_r.c (__getmntent_r): Likewise.
* posix/wordexp.c (parse_arith): Likewise.
(parse_backtick): Likewise.
* resolv/ns_ttl.c (ns_parse_ttl): Likewise.
* sysdeps/x86/cpu-features.c (init_cpu_features): Likewise.
* sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise.
The test case misc/tst-efgcvt.c only tests the double variants of the
Old-fashioned System V number-to-string functions: ecvt, fcvt, and their
re-entrant counterparts. With a few macros, the code can be reused for
the long double versions of these functions. A future patch will reuse
it again for IEEE long double on powerpc64le.
Tested for powerpc and powerpc64le.
__nldbl___vsyslog_chk will ultimately want to pass PRINTF_LDBL_IS_DBL
down to __vfprintf_internal *as well as* possibly setting PRINTF_FORTIFY.
To make that possible, we need a __vsyslog_internal that takes the
same flags as printf. The code in misc/syslog.c does also get a
little simpler.
Tested for powerpc and powerpc64le.
GCC 9 has gained an enhancement to help detect attribute mismatches
between alias declarations and their targets. It consists of a new
warning, -Wattribute-alias, an enhancement to an existing warning,
-Wmissing-attributes, and a new attribute called copy.
The purpose of the warnings is to help identify either possible bugs
(an alias declared with more restrictive attributes than its target
promises) or optimization or diagnostic opportunities (an alias target
missing some attributes that it could be declared with that might
benefit analysis and code generation). The purpose of the new
attribute is to easily apply (almost) the same set of attributes
to one declaration as those already present on another.
As expected (and intended) the enhancement triggers warnings for
many alias declarations in Glibc code. This change, tested on
x86_64-linux, avoids all instances of the new warnings by making
use of the attribute where appropriate. To fully benefit from
the enhancement Glibc will need to be compiled with
-Wattribute-alias=2 and remaining warnings reviewed and dealt with
(there are a couple of thousand but most should be straightforward
to deal with).
ChangeLog:
* include/libc-symbols.h (__attribute_copy__): Define macro unless
it's already defined.
(_strong_alias): Use __attribute_copy__.
(_weak_alias, __hidden_ver1, __hidden_nolink2): Same.
* misc/sys/cdefs.h (__attribute_copy__): New macro.
* sysdeps/x86_64/multiarch/memchr.c (memchr): Use __attribute_copy__.
* sysdeps/x86_64/multiarch/memcmp.c (memcmp): Same.
* sysdeps/x86_64/multiarch/mempcpy.c (mempcpy): Same.
* sysdeps/x86_64/multiarch/memset.c (memset): Same.
* sysdeps/x86_64/multiarch/stpcpy.c (stpcpy): Same.
* sysdeps/x86_64/multiarch/strcat.c (strcat): Same.
* sysdeps/x86_64/multiarch/strchr.c (strchr): Same.
* sysdeps/x86_64/multiarch/strcmp.c (strcmp): Same.
* sysdeps/x86_64/multiarch/strcpy.c (strcpy): Same.
* sysdeps/x86_64/multiarch/strcspn.c (strcspn): Same.
* sysdeps/x86_64/multiarch/strlen.c (strlen): Same.
* sysdeps/x86_64/multiarch/strncmp.c (strncmp): Same.
* sysdeps/x86_64/multiarch/strncpy.c (strncpy): Same.
* sysdeps/x86_64/multiarch/strnlen.c (strnlen): Same.
* sysdeps/x86_64/multiarch/strpbrk.c (strpbrk): Same.
* sysdeps/x86_64/multiarch/strrchr.c (strrchr): Same.
* sysdeps/x86_64/multiarch/strspn.c (strspn): Same.
The function do_test, in tst-efgcvt.c, increments an error counter for
each error that it finds, then returns it to the test framework.
However, the test framework does not expect an error count as return,
but zero for a passing test, one for a failing test, or 77 for an
unsupported test. Alternatively, the framework provides the function
support_record_failure that records errors, which then allows the test
program to return zero unconditionally.
This patch removes the error counter, replaces each increment of the
counter with a call to support_record_failure, and makes do_test
unconditionally return zero.
Tested for powerpc64le (as-is and with a patched results table to check
that the error reporting actually works).
* misc/tst-efgcvt.c: Include support/check.h and
support/test-driver.c. Do not include test-skeleton.c.
(error_count): Remove.
(output_error): Replace increments to error_count with calls to
support_record_failure.
(output_r_error): Likewise.
(special): Likewise.
(do_test): Unconditionally return zero.
(TEST_FUNCTION): Remove.
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.
