bug#32452: 26.1; gnutls_try_handshake maxes out cpu retrying when server is a bit busy

[Paul Eggert <eggert@cs.ucla.edu>]

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On 3/1/22 17:22, Lars Ingebrigtsen wrote:

> --- a/lib/gnulib.mk.in
> +++ b/lib/gnulib.mk.in
> @@ -129,6 +129,7 @@
>   #  minmax \
>   #  mkostemp \
>   #  mktime \
> +#  nanosleep \
>   #  nproc \
>   #  nstrftime \
>   #  pathmax \
> @@ -2497,6 +2498,16 @@ EXTRA_libgnu_a_SOURCES += mktime.c
>   endif
>   ## end   gnulib module mktime-internal
>   
> +## begin gnulib module nanosleep
> +ifeq (,$(OMIT_GNULIB_MODULE_nanosleep))
> +
> +ifneq (,$(GL_COND_OBJ_NANOSLEEP_CONDITION))
> +libgnu_a_SOURCES += nanosleep.c
> +endif
> +
> +endif
> +## end   gnulib module nanosleep
> +
>   ## begin gnulib module nproc
>   ifeq (,$(OMIT_GNULIB_MODULE_nproc))
>   

This diff is wrong, as it omits a line "GL_COND_OBJ_NANOSLEEP_CONDITION 
= @GL_COND_OBJ_NANOSLEEP_CONDITION@".

I ran what should have been something like your commands and got the 
attached patch. One way forward is for you to simply install the 
attached patch and move on from there. Or we can continue to look into 
why things work for me and not for you. I suppose it could be an 
Autoconf bug on your platform, but it'd be an odd one.

Here's a shell transcript of what I did to get the attached patch, on 
Fedora 35 x86-64:

   $ git clone master master-tmp
   Cloning into 'master-tmp'...
   done.
   Updating files: 100% (4608/4608), done.
   $ cd master-tmp
   $ git log HEAD^!
   commit 689a34e2153ec558dbf406809a5e58489250fe1a (HEAD -> master, 
origin/master, origin/HEAD)
   Author: Po Lu <luangruo@yahoo.com>
   Date:   Wed Mar 2 09:46:44 2022 +0800

       Dismiss help text when item becomes unactivated on oldXMenu

       * oldXMenu/Activate.c (XMenuActivate): Dismiss help text when
       leaving an item.
   $ (cd ../gnulib && git log HEAD^! )
   commit 8c4f4d7a3c28f88b64fce2fb1d0dc0e570d1a482 (HEAD -> master, 
origin/master, origin/HEAD)
   Author: Paul Eggert <eggert@cs.ucla.edu>
   Date:   Tue Mar 1 10:01:22 2022 -0800

       Create lib/Makefile.am after gnulib-comp.m4

       * gnulib-tool (func_import): Create library makefile after
       creating gnulib-comp.m4.  With --gnu-make, the latter depends on
       the former.  See <https://bugs.gnu.org/32452#109>.
   $ sed -i 's/nproc nstrftime/nanosleep &/' admin/merge-gnulib
   $ admin/merge-gnulib
   Checking whether you have the necessary tools...
   (Read INSTALL.REPO for more details on building Emacs)
   Checking for autoconf (need at least version 2.65) ... ok
   Your system has the required tools.
   Building aclocal.m4 ...
   Running 'autoreconf -fi -I m4' ...
   Configuring local git repository...
   '.git/config' -> '.git/config.~1~'
   git config transfer.fsckObjects 'true'
   git config diff.cpp.xfuncname '!^[ 
\t]*[A-Za-z_][A-Za-z_0-9]*:[[:space:]]*($|/[/*])
   ^((::[[:space:]]*)?[A-Za-z_][A-Za-z_0-9]*[[:space:]]*\(.*)$
   ^((#define[[:space:]]|DEFUN).*)$'
   git config diff.elisp.xfuncname 
'^\([^[:space:]]*def[^[:space:]]+[[:space:]]+([^()[:space:]]+)'
   git config diff.m4.xfuncname '^((m4_)?define|A._DEFUN(_ONCE)?)\([^),]*'
   git config diff.make.xfuncname 
'^([$.[:alnum:]_].*:|[[:alnum:]_]+[[:space:]]*([*:+]?[:?]?|!?)=|define .*)'
   git config diff.shell.xfuncname 
'^([[:space:]]*[[:alpha:]_][[:alnum:]_]*[[:space:]]*\(\)|[[:alpha:]_][[:alnum:]_]*=)'
   git config diff.texinfo.xfuncname 
'^@node[[:space:]]+([^,[:space:]][^,]+)'
   Installing git hooks...
   'build-aux/git-hooks/commit-msg' -> '.git/hooks/commit-msg'
   'build-aux/git-hooks/pre-commit' -> '.git/hooks/pre-commit'
   'build-aux/git-hooks/prepare-commit-msg' -> 
'.git/hooks/prepare-commit-msg'
   '.git/hooks/applypatch-msg.sample' -> '.git/hooks/applypatch-msg'
   '.git/hooks/pre-applypatch.sample' -> '.git/hooks/pre-applypatch'
   You can now run './configure'.
   Module list with included dependencies (indented):
       absolute-header
       acl-permissions
     alloca-opt
       allocator
       at-internal
       attribute
     binary-io
       builtin-expect
     byteswap
     c-ctype
     c-strcase
       c99
     canonicalize-lgpl
     careadlinkat
       clock-time
       cloexec
     close-stream
     copy-file-range
     count-leading-zeros
     count-one-bits
     count-trailing-zeros
     crypto/md5
     crypto/md5-buffer
     crypto/sha1-buffer
     crypto/sha256-buffer
     crypto/sha512-buffer
     d-type
     diffseq
       dirent
       dirfd
     double-slash-root
     dtoastr
     dtotimespec
     dup2
       dynarray
       eloop-threshold
     environ
       errno
       euidaccess
     execinfo
     explicit_bzero
       extensions
       extern-inline
     faccessat
     fchmodat
     fcntl
     fcntl-h
     fdopendir
     file-has-acl
     filemode
     filename
     filevercmp
     flexmember
       fpending
     fpieee
     free-posix
     fstatat
     fsusage
     fsync
     futimens
       gen-header
       getdtablesize
       getgroups
     getloadavg
     getopt-gnu
       getopt-posix
     getrandom
       gettext-h
     gettime
     gettimeofday
     gitlog-to-changelog
       group-member
       idx
     ieee754-h
     ignore-value
       include_next
     intprops
       inttypes-incomplete
     largefile
       lchmod
       libc-config
     libgmp
       limits-h
     lstat
       malloc-gnu
       malloc-posix
     manywarnings
     memmem-simple
     mempcpy
     memrchr
     minmax
     mkostemp
     mktime
       mktime-internal
       multiarch
     nanosleep
       nocrash
     nproc
     nstrftime
       open
       openat-h
     pathmax
     pipe2
     pselect
     pthread_sigmask
     qcopy-acl
       rawmemchr
     readlink
     readlinkat
       realloc-gnu
       realloc-posix
     regex
       root-uid
       scratch_buffer
     sig2str
     sigdescr_np
       signal-h
       snippet/_Noreturn
       snippet/arg-nonnull
       snippet/c++defs
       snippet/warn-on-use
     socklen
       ssize_t
     stat-time
     std-gnu11
     stdalign
     stddef
       stdint
     stdio
       stdlib
     stpcpy
       string
     strnlen
     strtoimax
       strtoll
     symlink
       sys_random
       sys_select
     sys_stat
     sys_time
       sys_types
     tempname
     time
     time_r
     time_rz
     timegm
     timer-time
       timespec
     timespec-add
     timespec-sub
       u64
       unistd
     unlocked-io
       unlocked-io-internal
     update-copyright
       utimens
     utimensat
       vararrays
       verify
     vla
     warnings
       xalloc-oversized
   File list:
     build-aux/gitlog-to-changelog
     build-aux/update-copyright
     lib/_Noreturn.h
     lib/acl-errno-valid.c
     lib/acl-internal.c
     lib/acl-internal.h
     lib/acl.h
     lib/acl_entries.c
     lib/alloca.in.h
     lib/allocator.c
     lib/allocator.h
     lib/arg-nonnull.h
     lib/at-func.c
     lib/attribute.h
     lib/binary-io.c
     lib/binary-io.h
     lib/byteswap.in.h
     lib/c++defs.h
     lib/c-ctype.c
     lib/c-ctype.h
     lib/c-strcase.h
     lib/c-strcasecmp.c
     lib/c-strncasecmp.c
     lib/canonicalize-lgpl.c
     lib/careadlinkat.c
     lib/careadlinkat.h
     lib/cdefs.h
     lib/cloexec.c
     lib/cloexec.h
     lib/close-stream.c
     lib/close-stream.h
     lib/copy-file-range.c
     lib/count-leading-zeros.c
     lib/count-leading-zeros.h
     lib/count-one-bits.c
     lib/count-one-bits.h
     lib/count-trailing-zeros.c
     lib/count-trailing-zeros.h
     lib/diffseq.h
     lib/dirent.in.h
     lib/dirfd.c
     lib/dtoastr.c
     lib/dtotimespec.c
     lib/dup2.c
     lib/dynarray.h
     lib/eloop-threshold.h
     lib/errno.in.h
     lib/euidaccess.c
     lib/execinfo.c
     lib/execinfo.in.h
     lib/explicit_bzero.c
     lib/faccessat.c
     lib/fchmodat.c
     lib/fcntl.c
     lib/fcntl.in.h
     lib/fdopendir.c
     lib/file-has-acl.c
     lib/filemode.c
     lib/filemode.h
     lib/filename.h
     lib/filevercmp.c
     lib/filevercmp.h
     lib/flexmember.h
     lib/fpending.c
     lib/fpending.h
     lib/free.c
     lib/fstatat.c
     lib/fsusage.c
     lib/fsusage.h
     lib/fsync.c
     lib/ftoastr.c
     lib/ftoastr.h
     lib/futimens.c
     lib/get-permissions.c
     lib/getdtablesize.c
     lib/getgroups.c
     lib/getloadavg.c
     lib/getopt-cdefs.in.h
     lib/getopt-core.h
     lib/getopt-ext.h
     lib/getopt-pfx-core.h
     lib/getopt-pfx-ext.h
     lib/getopt.c
     lib/getopt.in.h
     lib/getopt1.c
     lib/getopt_int.h
     lib/getrandom.c
     lib/gettext.h
     lib/gettime.c
     lib/gettimeofday.c
     lib/gl_openssl.h
     lib/group-member.c
     lib/idx.h
     lib/ieee754.in.h
     lib/ignore-value.h
     lib/intprops.h
     lib/inttypes.in.h
     lib/lchmod.c
     lib/libc-config.h
     lib/limits.in.h
     lib/lstat.c
     lib/malloc.c
     lib/malloc/dynarray-skeleton.c
     lib/malloc/dynarray.h
     lib/malloc/dynarray_at_failure.c
     lib/malloc/dynarray_emplace_enlarge.c
     lib/malloc/dynarray_finalize.c
     lib/malloc/dynarray_resize.c
     lib/malloc/dynarray_resize_clear.c
     lib/malloc/scratch_buffer.h
     lib/malloc/scratch_buffer_dupfree.c
     lib/malloc/scratch_buffer_grow.c
     lib/malloc/scratch_buffer_grow_preserve.c
     lib/malloc/scratch_buffer_set_array_size.c
     lib/md5-stream.c
     lib/md5.c
     lib/md5.h
     lib/memmem.c
     lib/mempcpy.c
     lib/memrchr.c
     lib/mini-gmp-gnulib.c
     lib/mini-gmp.c
     lib/mini-gmp.h
     lib/minmax.h
     lib/mkostemp.c
     lib/mktime-internal.h
     lib/mktime.c
     lib/nanosleep.c
     lib/nproc.c
     lib/nproc.h
     lib/nstrftime.c
     lib/open.c
     lib/openat-priv.h
     lib/openat-proc.c
     lib/openat.h
     lib/pathmax.h
     lib/pipe2.c
     lib/pselect.c
     lib/pthread_sigmask.c
     lib/qcopy-acl.c
     lib/rawmemchr.c
     lib/rawmemchr.valgrind
     lib/readlink.c
     lib/readlinkat.c
     lib/realloc.c
     lib/regcomp.c
     lib/regex.c
     lib/regex.h
     lib/regex_internal.c
     lib/regex_internal.h
     lib/regexec.c
     lib/root-uid.h
     lib/scratch_buffer.h
     lib/set-permissions.c
     lib/sha1.c
     lib/sha1.h
     lib/sha256.c
     lib/sha256.h
     lib/sha512.c
     lib/sha512.h
     lib/sig2str.c
     lib/sig2str.h
     lib/sigdescr_np.c
     lib/signal.in.h
     lib/stat-time.c
     lib/stat-time.h
     lib/stdalign.in.h
     lib/stddef.in.h
     lib/stdint.in.h
     lib/stdio-impl.h
     lib/stdio-read.c
     lib/stdio-write.c
     lib/stdio.in.h
     lib/stdlib.in.h
     lib/stpcpy.c
     lib/str-two-way.h
     lib/strftime.h
     lib/string.in.h
     lib/strnlen.c
     lib/strtoimax.c
     lib/strtol.c
     lib/strtoll.c
     lib/symlink.c
     lib/sys_random.in.h
     lib/sys_select.in.h
     lib/sys_stat.in.h
     lib/sys_time.in.h
     lib/sys_types.in.h
     lib/tempname.c
     lib/tempname.h
     lib/time-internal.h
     lib/time.in.h
     lib/time_r.c
     lib/time_rz.c
     lib/timegm.c
     lib/timespec-add.c
     lib/timespec-sub.c
     lib/timespec.c
     lib/timespec.h
     lib/u64.c
     lib/u64.h
     lib/unistd.c
     lib/unistd.in.h
     lib/unlocked-io.h
     lib/utimens.c
     lib/utimens.h
     lib/utimensat.c
     lib/verify.h
     lib/vla.h
     lib/warn-on-use.h
     lib/xalloc-oversized.h
     m4/00gnulib.m4
     m4/__inline.m4
     m4/absolute-header.m4
     m4/acl.m4
     m4/alloca.m4
     m4/builtin-expect.m4
     m4/byteswap.m4
     m4/canonicalize.m4
     m4/clock_time.m4
     m4/copy-file-range.m4
     m4/d-type.m4
     m4/dirent_h.m4
     m4/dirfd.m4
     m4/double-slash-root.m4
     m4/dup2.m4
     m4/eealloc.m4
     m4/environ.m4
     m4/errno_h.m4
     m4/euidaccess.m4
     m4/execinfo.m4
     m4/explicit_bzero.m4
     m4/extensions.m4
     m4/extern-inline.m4
     m4/faccessat.m4
     m4/fchmodat.m4
     m4/fcntl-o.m4
     m4/fcntl.m4
     m4/fcntl_h.m4
     m4/fdopendir.m4
     m4/filemode.m4
     m4/flexmember.m4
     m4/fpending.m4
     m4/fpieee.m4
     m4/free.m4
     m4/fstatat.m4
     m4/fsusage.m4
     m4/fsync.m4
     m4/futimens.m4
     m4/getdtablesize.m4
     m4/getgroups.m4
     m4/getloadavg.m4
     m4/getopt.m4
     m4/getrandom.m4
     m4/gettime.m4
     m4/gettimeofday.m4
     m4/gl-openssl.m4
     m4/gnulib-common.m4
     m4/group-member.m4
     m4/ieee754-h.m4
     m4/include_next.m4
     m4/inttypes.m4
     m4/largefile.m4
     m4/lchmod.m4
     m4/libgmp.m4
     m4/limits-h.m4
     m4/lstat.m4
     m4/malloc.m4
     m4/manywarnings-c++.m4
     m4/manywarnings.m4
     m4/mbstate_t.m4
     m4/md5.m4
     m4/memmem.m4
     m4/mempcpy.m4
     m4/memrchr.m4
     m4/minmax.m4
     m4/mkostemp.m4
     m4/mktime.m4
     m4/mode_t.m4
     m4/multiarch.m4
     m4/nanosleep.m4
     m4/nocrash.m4
     m4/nproc.m4
     m4/nstrftime.m4
     m4/off_t.m4
     m4/open-cloexec.m4
     m4/open-slash.m4
     m4/open.m4
     m4/pathmax.m4
     m4/pid_t.m4
     m4/pipe2.m4
     m4/pselect.m4
     m4/pthread_sigmask.m4
     m4/rawmemchr.m4
     m4/readlink.m4
     m4/readlinkat.m4
     m4/realloc.m4
     m4/regex.m4
     m4/sha1.m4
     m4/sha256.m4
     m4/sha512.m4
     m4/sig2str.m4
     m4/sigdescr_np.m4
     m4/signal_h.m4
     m4/socklen.m4
     m4/ssize_t.m4
     m4/stat-time.m4
     m4/std-gnu11.m4
     m4/stdalign.m4
     m4/stddef_h.m4
     m4/stdint.m4
     m4/stdio_h.m4
     m4/stdlib_h.m4
     m4/stpcpy.m4
     m4/string_h.m4
     m4/strnlen.m4
     m4/strtoimax.m4
     m4/strtoll.m4
     m4/symlink.m4
     m4/sys_random_h.m4
     m4/sys_select_h.m4
     m4/sys_socket_h.m4
     m4/sys_stat_h.m4
     m4/sys_time_h.m4
     m4/sys_types_h.m4
     m4/tempname.m4
     m4/time_h.m4
     m4/time_r.m4
     m4/time_rz.m4
     m4/timegm.m4
     m4/timer_time.m4
     m4/timespec.m4
     m4/tm_gmtoff.m4
     m4/unistd_h.m4
     m4/unlocked-io.m4
     m4/utimens.m4
     m4/utimensat.m4
     m4/utimes.m4
     m4/vararrays.m4
     m4/warn-on-use.m4
     m4/warnings.m4
     m4/wchar_t.m4
     m4/wint_t.m4
     m4/year2038.m4
     m4/zzgnulib.m4
   Copying file lib/gl_openssl.h
   Copying file lib/nanosleep.c
   Copying file lib/stdio-read.c
   Copying file lib/stdio-write.c
   Copying file m4/fcntl-o.m4
   Copying file m4/gl-openssl.m4
   Copying file m4/gnulib-tool.m4
   Copying file m4/manywarnings-c++.m4
   Copying file m4/nanosleep.m4
   Copying file m4/warn-on-use.m4
   Copying file m4/wint_t.m4
   Creating m4/gnulib-cache.m4
   Updating m4/gnulib-comp.m4 (backup in m4/gnulib-comp.m4~)
   Updating lib/gnulib.mk.in (backup in lib/gnulib.mk.in~)
   Finished.

   You may need to add #include directives for the following .h files.
     #include <alloca.h>
     #include <byteswap.h>
     #include <dirent.h>
     #include <execinfo.h>
     #include <fcntl.h>
     #include <getopt.h>
     #include <gmp.h>
     #include <ieee754.h>
     #include <inttypes.h>
     #include <regex.h>
     #include <signal.h>
     #include <stdalign.h>
     #include <stddef.h>
     #include <stdio.h>
     #include <stdlib.h>
     #include <string.h>
     #include <sys/random.h>
     #include <sys/select.h>
     #include <sys/stat.h>
     #include <sys/time.h>
     #include <time.h>
     #include <unistd.h>
     #include "acl.h"
     #include "binary-io.h"
     #include "c-ctype.h"
     #include "c-strcase.h"
     #include "careadlinkat.h"
     #include "close-stream.h"
     #include "count-leading-zeros.h"
     #include "count-one-bits.h"
     #include "count-trailing-zeros.h"
     #include "diffseq.h"
     #include "filemode.h"
     #include "filename.h"
     #include "filevercmp.h"
     #include "fsusage.h"
     #include "ftoastr.h"
     #include "ignore-value.h"
     #include "intprops.h"
     #include "md5.h"
     #include "minmax.h"
     #include "nproc.h"
     #include "pathmax.h"
     #include "sha1.h"
     #include "sha256.h"
     #include "sha512.h"
     #include "sig2str.h"
     #include "stat-time.h"
     #include "strftime.h"
     #include "tempname.h"
     #include "timespec.h"
     #include "unlocked-io.h"
     #include <sys/types.h>
     #if HAVE_SYS_SOCKET_H
     # include <sys/socket.h>
     #elif HAVE_WS2TCPIP_H
     # include <ws2tcpip.h>
     #endif

   You may need to use the following Makefile variables when linking.
   Use them in <program>_LDADD when linking a program, or
   in <library>_a_LDFLAGS or <library>_la_LDFLAGS when linking a library.
     $(GETLOADAVG_LIBS)
     $(LIBTHREAD)
     $(LIB_ACL)
     $(LIB_CLOCK_GETTIME)
     $(LIB_CRYPTO)
     $(LIB_EACCESS)
     $(LIB_EXECINFO)
     $(LIB_GETRANDOM)
     $(LIB_HAS_ACL)
     $(LIB_MBRTOWC)
     $(LIB_NANOSLEEP)
     $(LIB_PTHREAD_SIGMASK)
     $(LIB_SELECT)
     $(LIB_TIMER_TIME)
     $(LTLIBGMP) when linking with libtool, $(LIBGMP) otherwise
     $(LTLIBINTL) when linking with libtool, $(LIBINTL) otherwise

   Don't forget to
     - "include gnulib.mk.in" from within "lib/Makefile.am",
     - mention "-I m4" in ACLOCAL_AMFLAGS in Makefile.am
       or add an AC_CONFIG_MACRO_DIRS([m4]) invocation in ./configure.ac,
     - mention "m4/gnulib-cache.m4" in EXTRA_DIST in Makefile.am,
     - invoke gl_EARLY in ./configure.ac, right after AC_PROG_CC,
     - invoke gl_INIT in ./configure.ac.
   Checking whether you have the necessary tools...
   (Read INSTALL.REPO for more details on building Emacs)
   Checking for autoconf (need at least version 2.65) ... ok
   Your system has the required tools.
   Building aclocal.m4 ...
   Running 'autoreconf -fi -I m4' ...
   You can now run './configure'.
   $ git status
   On branch master
   Your branch is up to date with 'origin/master'.

   Changes not staged for commit:
     (use "git add <file>..." to update what will be committed)
     (use "git restore <file>..." to discard changes in working directory)
	  modified:   admin/merge-gnulib
	  modified:   lib/gnulib.mk.in
	  modified:   m4/gnulib-comp.m4

   Untracked files:
     (use "git add <file>..." to include in what will be committed)
	  lib/nanosleep.c
	  m4/nanosleep.m4
	  merge-gnulib.diff

   no changes added to commit (use "git add" and/or "git commit -a")
   $ git checkout -b for-larsi
   Switched to a new branch 'for-larsi'
   $ git add lib/nanosleep.c m4/nanosleep.m4 admin/merge-gnulib 
lib/gnulib.mk.in m4/gnulib-comp.m4
   $ git commit -m'Add Gnulib nanosleep module'
   [for-larsi 2020d4fc91] Add Gnulib nanosleep module
    5 files changed, 355 insertions(+), 1 deletion(-)
    create mode 100644 lib/nanosleep.c
    create mode 100644 m4/nanosleep.m4
   $ git format-patch -1
   0001-Add-Gnulib-nanosleep-module.patch
   $

[-- Attachment #2: 0001-Add-Gnulib-nanosleep-module.patch --]
[-- Type: text/x-patch, Size: 15273 bytes --]

From 2020d4fc91bf704a2572e7b68baca615f88a9144 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Tue, 1 Mar 2022 18:04:38 -0800
Subject: [PATCH] Add Gnulib nanosleep module

---
 admin/merge-gnulib |   2 +-
 lib/gnulib.mk.in   |  13 +++
 lib/nanosleep.c    | 195 +++++++++++++++++++++++++++++++++++++++++++++
 m4/gnulib-comp.m4  |   7 ++
 m4/nanosleep.m4    | 139 ++++++++++++++++++++++++++++++++
 5 files changed, 355 insertions(+), 1 deletion(-)
 create mode 100644 lib/nanosleep.c
 create mode 100644 m4/nanosleep.m4

diff --git a/admin/merge-gnulib b/admin/merge-gnulib
index fec469c017..ea3d23686f 100755
--- a/admin/merge-gnulib
+++ b/admin/merge-gnulib
@@ -40,7 +40,7 @@ GNULIB_MODULES=
   getloadavg getopt-gnu getrandom gettime gettimeofday gitlog-to-changelog
   ieee754-h ignore-value intprops largefile libgmp lstat
   manywarnings memmem-simple mempcpy memrchr minmax mkostemp mktime
-  nproc nstrftime
+  nanosleep nproc nstrftime
   pathmax pipe2 pselect pthread_sigmask
   qcopy-acl readlink readlinkat regex
   sig2str sigdescr_np socklen stat-time std-gnu11 stdalign stddef stdio
diff --git a/lib/gnulib.mk.in b/lib/gnulib.mk.in
index 3a9f5b9818..3deeca98be 100644
--- a/lib/gnulib.mk.in
+++ b/lib/gnulib.mk.in
@@ -129,6 +129,7 @@
 #  minmax \
 #  mkostemp \
 #  mktime \
+#  nanosleep \
 #  nproc \
 #  nstrftime \
 #  pathmax \
@@ -207,6 +208,7 @@ CPP = @CPP@
 CPPFLAGS = @CPPFLAGS@
 CRYPTOLIB = @CRYPTOLIB@
 CXX = @CXX@
+CXXCPP = @CXXCPP@
 CXXFLAGS = @CXXFLAGS@
 CYGWIN_OBJ = @CYGWIN_OBJ@
 C_SWITCH_MACHINE = @C_SWITCH_MACHINE@
@@ -283,6 +285,7 @@ GL_COND_OBJ_MEMPCPY_CONDITION = @GL_COND_OBJ_MEMPCPY_CONDITION@
 GL_COND_OBJ_MEMRCHR_CONDITION = @GL_COND_OBJ_MEMRCHR_CONDITION@
 GL_COND_OBJ_MINI_GMP_GNULIB_CONDITION = @GL_COND_OBJ_MINI_GMP_GNULIB_CONDITION@
 GL_COND_OBJ_MKOSTEMP_CONDITION = @GL_COND_OBJ_MKOSTEMP_CONDITION@
+GL_COND_OBJ_NANOSLEEP_CONDITION = @GL_COND_OBJ_NANOSLEEP_CONDITION@
 GL_COND_OBJ_OPEN_CONDITION = @GL_COND_OBJ_OPEN_CONDITION@
 GL_COND_OBJ_PSELECT_CONDITION = @GL_COND_OBJ_PSELECT_CONDITION@
 GL_COND_OBJ_PTHREAD_SIGMASK_CONDITION = @GL_COND_OBJ_PTHREAD_SIGMASK_CONDITION@
@@ -2497,6 +2500,16 @@ EXTRA_libgnu_a_SOURCES += mktime.c
 endif
 ## end   gnulib module mktime-internal
 
+## begin gnulib module nanosleep
+ifeq (,$(OMIT_GNULIB_MODULE_nanosleep))
+
+ifneq (,$(GL_COND_OBJ_NANOSLEEP_CONDITION))
+libgnu_a_SOURCES += nanosleep.c
+endif
+
+endif
+## end   gnulib module nanosleep
+
 ## begin gnulib module nproc
 ifeq (,$(OMIT_GNULIB_MODULE_nproc))
 
diff --git a/lib/nanosleep.c b/lib/nanosleep.c
new file mode 100644
index 0000000000..446794edc0
--- /dev/null
+++ b/lib/nanosleep.c
@@ -0,0 +1,195 @@
+/* Provide a replacement for the POSIX nanosleep function.
+
+   Copyright (C) 1999-2000, 2002, 2004-2022 Free Software Foundation, Inc.
+
+   This file is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   This file is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* written by Jim Meyering
+   and Bruno Haible for the native Windows part */
+
+#include <config.h>
+
+#include <time.h>
+
+#include "intprops.h"
+#include "verify.h"
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/select.h>
+#include <signal.h>
+
+#include <errno.h>
+
+#include <unistd.h>
+
+
+enum { BILLION = 1000 * 1000 * 1000 };
+
+#if HAVE_BUG_BIG_NANOSLEEP
+
+int
+nanosleep (const struct timespec *requested_delay,
+           struct timespec *remaining_delay)
+# undef nanosleep
+{
+  /* nanosleep mishandles large sleeps due to internal overflow problems.
+     The worst known case of this is Linux 2.6.9 with glibc 2.3.4, which
+     can't sleep more than 24.85 days (2^31 milliseconds).  Similarly,
+     cygwin 1.5.x, which can't sleep more than 49.7 days (2^32 milliseconds).
+     Solve this by breaking the sleep up into smaller chunks.  */
+
+  if (requested_delay->tv_nsec < 0 || BILLION <= requested_delay->tv_nsec)
+    {
+      errno = EINVAL;
+      return -1;
+    }
+
+  {
+    /* Verify that time_t is large enough.  */
+    verify (TYPE_MAXIMUM (time_t) / 24 / 24 / 60 / 60);
+    const time_t limit = 24 * 24 * 60 * 60;
+    time_t seconds = requested_delay->tv_sec;
+    struct timespec intermediate;
+    intermediate.tv_nsec = requested_delay->tv_nsec;
+
+    while (limit < seconds)
+      {
+        int result;
+        intermediate.tv_sec = limit;
+        result = nanosleep (&intermediate, remaining_delay);
+        seconds -= limit;
+        if (result)
+          {
+            if (remaining_delay)
+              remaining_delay->tv_sec += seconds;
+            return result;
+          }
+        intermediate.tv_nsec = 0;
+      }
+    intermediate.tv_sec = seconds;
+    return nanosleep (&intermediate, remaining_delay);
+  }
+}
+
+#elif defined _WIN32 && ! defined __CYGWIN__
+/* Native Windows platforms.  */
+
+# define WIN32_LEAN_AND_MEAN
+# include <windows.h>
+
+/* The Windows API function Sleep() has a resolution of about 15 ms and takes
+   at least 5 ms to execute.  We use this function for longer time periods.
+   Additionally, we use busy-looping over short time periods, to get a
+   resolution of about 0.01 ms.  In order to measure such short timespans,
+   we use the QueryPerformanceCounter() function.  */
+
+int
+nanosleep (const struct timespec *requested_delay,
+           struct timespec *remaining_delay)
+{
+  static bool initialized;
+  /* Number of performance counter increments per nanosecond,
+     or zero if it could not be determined.  */
+  static double ticks_per_nanosecond;
+
+  if (requested_delay->tv_nsec < 0 || BILLION <= requested_delay->tv_nsec)
+    {
+      errno = EINVAL;
+      return -1;
+    }
+
+  /* For requested delays of one second or more, 15ms resolution is
+     sufficient.  */
+  if (requested_delay->tv_sec == 0)
+    {
+      if (!initialized)
+        {
+          /* Initialize ticks_per_nanosecond.  */
+          LARGE_INTEGER ticks_per_second;
+
+          if (QueryPerformanceFrequency (&ticks_per_second))
+            ticks_per_nanosecond =
+              (double) ticks_per_second.QuadPart / 1000000000.0;
+
+          initialized = true;
+        }
+      if (ticks_per_nanosecond)
+        {
+          /* QueryPerformanceFrequency worked.  We can use
+             QueryPerformanceCounter.  Use a combination of Sleep and
+             busy-looping.  */
+          /* Number of milliseconds to pass to the Sleep function.
+             Since Sleep can take up to 8 ms less or 8 ms more than requested
+             (or maybe more if the system is loaded), we subtract 10 ms.  */
+          int sleep_millis = (int) requested_delay->tv_nsec / 1000000 - 10;
+          /* Determine how many ticks to delay.  */
+          LONGLONG wait_ticks = requested_delay->tv_nsec * ticks_per_nanosecond;
+          /* Start.  */
+          LARGE_INTEGER counter_before;
+          if (QueryPerformanceCounter (&counter_before))
+            {
+              /* Wait until the performance counter has reached this value.
+                 We don't need to worry about overflow, because the performance
+                 counter is reset at reboot, and with a frequency of 3.6E6
+                 ticks per second 63 bits suffice for over 80000 years.  */
+              LONGLONG wait_until = counter_before.QuadPart + wait_ticks;
+              /* Use Sleep for the longest part.  */
+              if (sleep_millis > 0)
+                Sleep (sleep_millis);
+              /* Busy-loop for the rest.  */
+              for (;;)
+                {
+                  LARGE_INTEGER counter_after;
+                  if (!QueryPerformanceCounter (&counter_after))
+                    /* QueryPerformanceCounter failed, but succeeded earlier.
+                       Should not happen.  */
+                    break;
+                  if (counter_after.QuadPart >= wait_until)
+                    /* The requested time has elapsed.  */
+                    break;
+                }
+              goto done;
+            }
+        }
+    }
+  /* Implementation for long delays and as fallback.  */
+  Sleep (requested_delay->tv_sec * 1000 + requested_delay->tv_nsec / 1000000);
+
+ done:
+  /* Sleep is not interruptible.  So there is no remaining delay.  */
+  if (remaining_delay != NULL)
+    {
+      remaining_delay->tv_sec = 0;
+      remaining_delay->tv_nsec = 0;
+    }
+  return 0;
+}
+
+#else
+/* Other platforms lacking nanosleep.
+   It's not clear whether these are still practical porting targets.
+   For now, just fall back on pselect.  */
+
+/* Suspend execution for at least *REQUESTED_DELAY seconds.  The
+   *REMAINING_DELAY part isn't implemented yet.  */
+
+int
+nanosleep (const struct timespec *requested_delay,
+           struct timespec *remaining_delay)
+{
+  return pselect (0, NULL, NULL, NULL, requested_delay, NULL);
+}
+#endif
diff --git a/m4/gnulib-comp.m4 b/m4/gnulib-comp.m4
index 1d31239d2d..fb5f1b52a4 100644
--- a/m4/gnulib-comp.m4
+++ b/m4/gnulib-comp.m4
@@ -140,6 +140,7 @@ AC_DEFUN
   # Code from module mktime:
   # Code from module mktime-internal:
   # Code from module multiarch:
+  # Code from module nanosleep:
   # Code from module nocrash:
   # Code from module nproc:
   # Code from module nstrftime:
@@ -430,6 +431,10 @@ AC_DEFUN
   fi
   gl_TIME_MODULE_INDICATOR([mktime])
   gl_MULTIARCH
+  gl_FUNC_NANOSLEEP
+  gl_CONDITIONAL([GL_COND_OBJ_NANOSLEEP],
+                 [test $HAVE_NANOSLEEP = 0 || test $REPLACE_NANOSLEEP = 1])
+  gl_TIME_MODULE_INDICATOR([nanosleep])
   gl_NPROC
   gl_FUNC_GNU_STRFTIME
   gl_PATHMAX
@@ -1304,6 +1309,7 @@ AC_DEFUN
   lib/mkostemp.c
   lib/mktime-internal.h
   lib/mktime.c
+  lib/nanosleep.c
   lib/nproc.c
   lib/nproc.h
   lib/nstrftime.c
@@ -1456,6 +1462,7 @@ AC_DEFUN
   m4/mktime.m4
   m4/mode_t.m4
   m4/multiarch.m4
+  m4/nanosleep.m4
   m4/nocrash.m4
   m4/nproc.m4
   m4/nstrftime.m4
diff --git a/m4/nanosleep.m4 b/m4/nanosleep.m4
new file mode 100644
index 0000000000..1964b1ea47
--- /dev/null
+++ b/m4/nanosleep.m4
@@ -0,0 +1,139 @@
+# serial 41
+
+dnl From Jim Meyering.
+dnl Check for the nanosleep function.
+dnl If not found, use the supplied replacement.
+dnl
+
+# Copyright (C) 1999-2001, 2003-2022 Free Software Foundation, Inc.
+
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_FUNC_NANOSLEEP],
+[
+ AC_REQUIRE([gl_TIME_H_DEFAULTS])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+ dnl Persuade glibc and Solaris <time.h> to declare nanosleep.
+ AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
+ AC_CHECK_DECLS_ONCE([alarm])
+
+ nanosleep_save_libs=$LIBS
+
+ # Solaris 2.5.1 needs -lposix4 to get the nanosleep function.
+ # Solaris 7 prefers the library name -lrt to the obsolescent name -lposix4.
+ LIB_NANOSLEEP=
+ AC_SUBST([LIB_NANOSLEEP])
+ AC_SEARCH_LIBS([nanosleep], [rt posix4],
+                [test "$ac_cv_search_nanosleep" = "none required" ||
+                 LIB_NANOSLEEP=$ac_cv_search_nanosleep])
+ if test "x$ac_cv_search_nanosleep" != xno; then
+   dnl The system has a nanosleep function.
+
+   AC_REQUIRE([gl_MULTIARCH])
+   if test $APPLE_UNIVERSAL_BUILD = 1; then
+     # A universal build on Apple Mac OS X platforms.
+     # The test result would be 'no (mishandles large arguments)' in 64-bit
+     # mode but 'yes' in 32-bit mode. But we need a configuration result that
+     # is valid in both modes.
+     gl_cv_func_nanosleep='no (mishandles large arguments)'
+   fi
+
+   AC_CACHE_CHECK([for working nanosleep],
+    [gl_cv_func_nanosleep],
+    [
+     AC_RUN_IFELSE(
+       [AC_LANG_SOURCE([[
+          #include <errno.h>
+          #include <limits.h>
+          #include <signal.h>
+          #include <time.h>
+          #include <unistd.h>
+          #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+          #define TYPE_MAXIMUM(t) \
+            ((t) (! TYPE_SIGNED (t) \
+                  ? (t) -1 \
+                  : ((((t) 1 << (sizeof (t) * CHAR_BIT - 2)) - 1) * 2 + 1)))
+
+          #if HAVE_DECL_ALARM
+          static void
+          check_for_SIGALRM (int sig)
+          {
+            if (sig != SIGALRM)
+              _exit (1);
+          }
+          #endif
+
+          int
+          main ()
+          {
+            static struct timespec ts_sleep;
+            static struct timespec ts_remaining;
+            /* Test for major problems first.  */
+            if (! nanosleep)
+              return 2;
+            ts_sleep.tv_sec = 0;
+            ts_sleep.tv_nsec = 1;
+            #if HAVE_DECL_ALARM
+            {
+              static struct sigaction act;
+              act.sa_handler = check_for_SIGALRM;
+              sigemptyset (&act.sa_mask);
+              sigaction (SIGALRM, &act, NULL);
+              alarm (1);
+              if (nanosleep (&ts_sleep, NULL) != 0)
+                return 3;
+              /* Test for a minor problem: the handling of large arguments.  */
+              ts_sleep.tv_sec = TYPE_MAXIMUM (time_t);
+              ts_sleep.tv_nsec = 999999999;
+              alarm (1);
+              if (nanosleep (&ts_sleep, &ts_remaining) != -1)
+                return 4;
+              if (errno != EINTR)
+                return 5;
+              if (ts_remaining.tv_sec <= TYPE_MAXIMUM (time_t) - 10)
+                return 6;
+            }
+            #else /* A simpler test for native Windows.  */
+            if (nanosleep (&ts_sleep, &ts_remaining) < 0)
+              return 3;
+            #endif
+            return 0;
+          }]])],
+       [gl_cv_func_nanosleep=yes],
+       [case $? in dnl (
+        4|5|6) gl_cv_func_nanosleep='no (mishandles large arguments)';; dnl (
+        *)   gl_cv_func_nanosleep=no;;
+        esac],
+       [case "$host_os" in dnl ((
+          linux*) # Guess it halfway works when the kernel is Linux.
+            gl_cv_func_nanosleep='guessing no (mishandles large arguments)' ;;
+          mingw*) # Guess no on native Windows.
+            gl_cv_func_nanosleep='guessing no' ;;
+          *)      # If we don't know, obey --enable-cross-guesses.
+            gl_cv_func_nanosleep="$gl_cross_guess_normal" ;;
+        esac
+       ])
+    ])
+   case "$gl_cv_func_nanosleep" in
+     *yes)
+       REPLACE_NANOSLEEP=0
+       ;;
+     *)
+       REPLACE_NANOSLEEP=1
+       case "$gl_cv_func_nanosleep" in
+         *"mishandles large arguments"*)
+           AC_DEFINE([HAVE_BUG_BIG_NANOSLEEP], [1],
+             [Define to 1 if nanosleep mishandles large arguments.])
+           ;;
+       esac
+       ;;
+   esac
+ else
+   HAVE_NANOSLEEP=0
+ fi
+ LIBS=$nanosleep_save_libs
+])
-- 
2.35.1