Currently there is no proper way to set the controlling terminal through
posix_spawn in race free manner [1]. This forces shell implementations
to keep using fork+exec when launching background process groups,
even when using posix_spawn yields better performance.
This patch adds a new GNU extension so the creating process can
configure the created process terminal group. This is done with a new
flag, POSIX_SPAWN_TCSETPGROUP, along with two new attribute functions:
posix_spawnattr_tcsetpgrp_np, and posix_spawnattr_tcgetpgrp_np.
The function sets a new attribute, spawn-tcgroupfd, that references to
the controlling terminal.
The controlling terminal is set after the spawn-pgroup attribute, and
uses the spawn-tcgroupfd along with current creating process group
(so it is composable with POSIX_SPAWN_SETPGROUP).
To create a process and set the controlling terminal, one can use the
following sequence:
posix_spawnattr_t attr;
posix_spawnattr_init (&attr);
posix_spawnattr_setflags (&attr, POSIX_SPAWN_TCSETPGROUP);
posix_spawnattr_tcsetpgrp_np (&attr, tcfd);
If the idea is also to create a new process groups:
posix_spawnattr_t attr;
posix_spawnattr_init (&attr);
posix_spawnattr_setflags (&attr, POSIX_SPAWN_TCSETPGROUP
| POSIX_SPAWN_SETPGROUP);
posix_spawnattr_tcsetpgrp_np (&attr, tcfd);
posix_spawnattr_setpgroup (&attr, 0);
The controlling terminal file descriptor is ignored if the new flag is
not set.
This interface is slight different than the one provided by QNX [2],
which only provides the POSIX_SPAWN_TCSETPGROUP flag. The QNX
documentation does not specify how the controlling terminal is obtained
nor how it iteracts with POSIX_SPAWN_SETPGROUP. Since a glibc
implementation is library based, it is more straightforward and avoid
requires additional file descriptor operations to request the caller
to setup the controlling terminal file descriptor (and it also allows
a bit less error handling by posix_spawn).
Checked on x86_64-linux-gnu and i686-linux-gnu.
[1] https://github.com/ksh93/ksh/issues/79
[2] https://www.qnx.com/developers/docs/7.0.0/index.html#com.qnx.doc.neutrino.lib_ref/topic/p/posix_spawn.html
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.
I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah. I don't
know why I run into these diagnostics whereas others evidently do not.
remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date. Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.
Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions. These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.
The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively. These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:
https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dchttps://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
* sysdeps/unix/bsd/getpt.c (__getpt): Add oflag parameter, pass
it to the _open call and rename to...
(__bsd_openpt): ... new function.
(__getpt): Reimplement on top of __bsd_openpt.
(__posix_openpt): Replace stub with implementation on top of __bsd_openpt.
(posix_openpt): Remove stub warning.
It refactor how signals are defined by each architecture. Instead of
include a generic header (bits/signum-generic.h) and undef non-default
values in an arch specific header (bits/signum.h) the new scheme uses a
common definition (bits/signum-generic.h) and each architectures add
its specific definitions on a new header (bits/signum-arch.h).
For Linux it requires copy some system default definitions to alpha,
hppa, and sparc. They are historical values and newer ports uses
the generic Linux signum-arch.h.
For Hurd the BSD signum is removed and moved to a new header (it is
used currently only on Hurd).
Checked on a build against all affected ABIs.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The POSIX implementation is used as default and both BSD and Linux
version are removed. It simplifies the implementation for
architectures that do not provide either __NR_waitpid or
__NR_wait4.
Checked on x86_64-linux-gnu and powerpc64le-linux-gnu.
ftime is an obsolete variation on gettimeofday, offering only
millisecond time resolution; it was probably a system call in ooold
versions of BSD Unix. For historic reasons, we had three
implementations of it. These are all consolidated into time/ftime.c,
and then the function is deprecated.
For some reason, the implementation of ftime in terms of gettimeofday
was rounding rather than truncating microseconds to milliseconds. In
all the other places where we use a higher-resolution time function to
implement a lower-resolution one, we truncate. ftime is changed to
match, just for tidiness' sake.
Like gettimeofday, ftime tries to report the time zone, and using that
information is always a bug. This patch dummies out the reported
timezone information; the timezone and dstflag fields of the
returned "struct timeb" will always be zero.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, and powerpc-linux-gnu.
Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Hide internal __tcgetattr function to allow direct access within libc.so
and libc.a without using GOT nor PLT.
[BZ #18822]
* include/termios.h (__tcgetattr): Add libc_hidden_proto.
* sysdeps/unix/bsd/tcgetattr.c (__tcgetattr): Add
libc_hidden_def.
* sysdeps/unix/sysv/linux/tcgetattr.c (__tcgetattr): Likewise.
* termios/tcgetattr.c (__tcgetattr): 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.
Many of the things defined by bits/signum.h are invariant across all
supported operating systems. This patch factors out all of them to a
new header bits/signum-generic.h, which each bits/signum.h will include
and then override whichever things need adjustment. Normally that will
mean, at most, adding or changing a few signal numbers.
A user-visible side effect is that the obsolete signal constant SIGUNUSED
(which is an alias for SIGSYS on all platforms that define it) is no
longer exposed by any version of bits/signum.h.
A side effect only relevant to glibc hackers is that _NSIG is now defined
in terms of __SIGRTMAX, instead of the other way around. This is because
__SIGRTMAX varies from platform to platform, but _NSIG==__SIGRTMAX+1 is
true universally. If your platform doesn't support realtime signals,
leave __SIGRTMAX equal to __SIGRTMIN.
I also added a Linux-specific test to make sure that our signal constants
match the ones in <asm/signal.h>, since we can't use that header (it's
not even vaguely namespace-clean).
* bits/signum-generic.h: Renamed from bits/signum.h.
Add proper multiple include guard and misuse check.
Define __SIGRTMIN = __SIGRTMAX = 32, and define _NSIG = __SIGRTMAX+1.
Move definition of SIGIO to "archaic names for compatibility" section.
* bits/signum.h: New file which just includes bits/signum-generic.h.
* sysdeps/unix/bsd/bits/signum.h
* sysdeps/unix/sysv/linux/bits/signum.h
* sysdeps/unix/sysv/linux/alpha/bits/signum.h
* sysdeps/unix/sysv/linux/hppa/bits/signum.h
* sysdeps/unix/sysv/linux/mips/bits/signum.h
* sysdeps/unix/sysv/linux/sparc/bits/signum.h
Just include <bits/signum-generic.h> and then add or adjust
signal constants. Do not define SIGUNUSED, SIGRTMIN, or SIGRTMAX.
* signal/Makefile: Install bits/signum-generic.h.
* signal/signal.h: Define SIGRTMIN and SIGRTMAX here.
* sysdeps/generic/siglist.h: SIGSYS and SIGWINCH are
universal. Prefer SIGPOLL to SIGIO. Simplify #ifdeffage.
* sysdeps/unix/sysv/linux/tst-signal-numbers.sh: New test.
* sysdeps/unix/sysv/linux/Makefile: Run it.
Various bits/signum.h headers define SIG_HOLD if __USE_UNIX98. That
should be __USE_XOPEN, as this macro is in XPG4. This patch fixes the
conditionals accordingly. Because of other header bugs, this does not
allow any XFAILs to be removed (however, the XPG4/signal.h/conform
XFAIL only depends on a few such straightforward header bugs, not on
the more complicated to fix ucontext_t issues, as ucontext_t isn't
included in signal.h in XPG4).
Tested for x86_64.
[BZ #21538]
* bits/signum.h (SIG_HOLD): Define if [__USE_XOPEN], not
[__USE_UNIX98].
* sysdeps/unix/bsd/bits/signum.h (SIG_HOLD): Likewise.
* sysdeps/unix/sysv/linux/alpha/bits/signum.h (SIG_HOLD):
Likewise.
* sysdeps/unix/sysv/linux/bits/signum.h (SIG_HOLD): Likewise.
* sysdeps/unix/sysv/linux/hppa/bits/signum.h (SIG_HOLD): Likewise.
* sysdeps/unix/sysv/linux/mips/bits/signum.h (SIG_HOLD): Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/signum.h (SIG_HOLD):
Likewise.
This avoids aliasing issues with GCC 6 in -fno-strict-aliasing
mode. (With implicit padding, not all data is copied.)
This change makes it explicit that struct sockaddr_storage is
only 126 bytes large on m68k (unlike elsewhere, where we end up
with the requested 128 bytes). The new test case makes sure that
this does not happen on other architectures.
The overloading approach in the W* macros was incompatible with
integer expressions of a type different from int. Applications
using union wait and these macros will have to migrate to the
POSIX-specified int status type.
Continuing the removal of unused __libc_* function names, this patch
removes the __libc_waitpid name.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch; __waitpid, which is exported from
shared libc, changes from weak to strong on some configurations, which
is of no significance).
* include/sys/wait.h (__libc_waitpid): Remove declaration.
* posix/waitpid.c (__libc_waitpid): Rename to __waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
* sysdeps/unix/bsd/waitpid.c (__libc_waitpid): Rename to
__waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
* sysdeps/unix/sysv/linux/i386/syscalls.list (waitpid): Remove
__libc_waitpid alias.
* sysdeps/unix/sysv/linux/m68k/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/powerpc/syscalls.list (waitpid):
Likewise.
* sysdeps/unix/sysv/linux/sh/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/sparc/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/tile/waitpid.S (__libc_waitpid): Remove
alias.
* sysdeps/unix/sysv/linux/waitpid.c (__libc_waitpid): Rename to
__waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
As discussed in
<https://sourceware.org/ml/libc-alpha/2012-04/msg00840.html> and
<https://sourceware.org/ml/libc-alpha/2012-04/msg00989.html>, it seems
appropriate to flatten sysdeps/unix/bsd/bsd4.4 into sysdeps/unix/bsd.
The bulk of the patch is just moving files. The only other changes
are: update paths in sysdeps/mach/hurd/Implies and
sysdeps/unix/sysv/linux/wait3.c; merge the two syscalls.list files,
with the removal of syscalls that were in
sysdeps/unix/bsd/syscalls.list but overridden in the bsd4.4 directory
by .c files there.
Tested x86_64. The installed shared libraries are identical before
and after the patch except for libc.so where the move of wait3.c
(included by sysdeps/unix/sysv/linux/wait3.c) affects debug info, but
the disassembly is unchanged.
* sysdeps/mach/hurd/Implies: Change unix/bsd/bsd4.4 to unix/bsd.
* sysdeps/unix/bsd/syscalls.list (chflags): Add entry from
sysdeps/unix/bsd/bsd4.4/syscalls.list.
(fchflags): Likewise.
(revoke): Likewise.
(setlogin): Likewise.
(sigaltstack): Likewise.
(wait4): Likewise.
(sigblock): Remove.
(sigsetmask): Likewise.
(wait3): Likewise.
(waitpid): Likewise.
* sysdeps/unix/bsd/bsd4.4/syscalls.list: Remove file.
* sysdeps/unix/sysv/linux/wait3.c: Update directory of included
file.
* sysdeps/unix/bsd/bsd4.4/Makefile: Move to ...
* sysdeps/unix/bsd/Makefile: ... here.
* sysdeps/unix/bsd/bsd4.4/Versions: Move to ...
* sysdeps/unix/bsd/Versions: ... here.
* sysdeps/unix/bsd/bsd4.4/bits/sockaddr.h: Move to ...
* sysdeps/unix/bsd/bits/sockaddr.h: ... here.
* sysdeps/unix/bsd/bsd4.4/cmsg_nxthdr.c: Move to ...
* sysdeps/unix/bsd/cmsg_nxthdr.c: ... here.
* sysdeps/unix/bsd/bsd4.4/sigblock.c: Move to ...
* sysdeps/unix/bsd/sigblock.c: ... here.
* sysdeps/unix/bsd/bsd4.4/sigsetmask.c: Move to ...
* sysdeps/unix/bsd/sigsetmask.c: ... here.
* sysdeps/unix/bsd/bsd4.4/sigvec.c: Move to ...
* sysdeps/unix/bsd/sigvec.c: ... here.
* sysdeps/unix/bsd/bsd4.4/tcdrain.c: Move to ...
* sysdeps/unix/bsd/tcdrain.c: ... here.
* sysdeps/unix/bsd/bsd4.4/tcgetattr.c: Move to ...
* sysdeps/unix/bsd/tcgetattr.c: ... here.
* sysdeps/unix/bsd/bsd4.4/tcsetattr.c: Move to ...
* sysdeps/unix/bsd/tcsetattr.c: ... here.
* sysdeps/unix/bsd/bsd4.4/wait.c: Move to ...
* sysdeps/unix/bsd/wait.c: ... here.
* sysdeps/unix/bsd/bsd4.4/wait3.c: Move to ...
* sysdeps/unix/bsd/wait3.c: ... here.
* sysdeps/unix/bsd/bsd4.4/waitpid.c: Move to ...
* sysdeps/unix/bsd/waitpid.c: ... here.
The bsd implementation of ulimit produces wrong return values, so remove it
in favour of the posix implementation.
The only regression for non-Linux implementations using bsd sysdeps and not
providing an own ulimit is that the __UL_GETMAXBRK case (which is non-standard)
is left unimplemented (giving EINVAL).
