glibc/include
Zack Weinberg 544ce845de getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that.  But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.

glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point.  getopt's
messages are translated, so they might not be ASCII.  So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer).  There isn't even a helper function,
the code is duplicated every time.

This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point.  (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.)  All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.

I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).

	* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
	(locked_vfxprintf): New helper function. Handle arbitrary
	multibyte strings, not just ASCII.
	* include/stdio.h: Declare __fxprintf_nocancel.

	* posix/getopt.c: When _LIBC is defined, define fprintf to
	__fxprintf_nocancel, flockfile to _IO_flockfile, and
	funlockfile to _IO_funlockfile.  When neither _LIBC nor
	_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
	funlockfile as no-ops.  (_getopt_internal_r): Remove all
	internal #ifdef _LIBC blocks; the standalone error-printing
	code can now be used for libc as well.  Add an
	flockfile/funlockfile pair around one case where the error
	message is printed in several chunks.  Don't use fputc.

	* posix/tst-getopt-cancel.c: New test.
	* posix/Makefile: Run it.
2017-04-07 07:48:57 -04:00
..
arpa nss_dns: Replace local declarations with declarations from a header file 2017-04-04 20:56:23 +02:00
bits Split helper classification macros from mathcalls.h 2017-03-15 09:39:16 -03:00
gnu Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
net Fix resolver if_* namespace (bug 17717). 2014-12-16 18:18:49 +00:00
netinet Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
programs Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
protocols
rpc sunrpc: Always obtain AF_INET addresses from NSS [BZ #20964] 2016-12-27 16:44:15 +01:00
rpcsvc Deprecate libnsl by default (only shared library will be 2017-03-21 15:14:27 +01:00
sys Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
aio.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
aliases.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
alloca.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
argp.h
argz.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
assert.h Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
atomic.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
byteswap.h
caller.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
complex.h conformtest: Fix namespace testing. 2013-09-04 20:47:21 +00:00
cpio.h Add more headers to include/ for conform tests. 2014-12-11 21:41:30 +00:00
crypt.h Add include/crypt.h. 2016-10-28 22:40:16 -04:00
ctype.h Rename bits/libc-tsd.h to libc-tsd.h (bug 14912). 2015-09-03 20:33:46 +00:00
des.h
dirent.h Mark internal dirent functions hidden 2015-10-15 14:15:41 -07:00
dlfcn.h Mark _dl_catch_error hidden 2015-10-15 14:13:50 -07:00
elf.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
endian.h
envz.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
err.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
errno.h Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
error.h
execinfo.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
fcntl.h hurd: Do not hide rtld symbols which need to be preempted 2016-03-20 19:51:42 +01:00
features.h Clean up conditionals for declaration of gets. 2017-02-25 09:47:51 -05:00
fenv.h Mark fegetround pure (bug 16296). 2015-09-15 20:36:50 +00:00
fmtmsg.h Add more headers to include/ for conform tests. 2014-12-11 21:41:30 +00:00
fnmatch.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
fpu_control.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
ftw.h
gconv.h
getopt_int.h
getopt.h getopt: remove USE_NONOPTION_FLAGS 2017-04-07 07:45:53 -04:00
glob.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
gmp.h
gnu-versions.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
grp-merge.h NSS: Implement group merging support. 2016-04-29 22:18:21 -04:00
grp.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
gshadow.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
iconv.h
ifaddrs.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
ifunc-impl-list.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
inline-hashtab.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
langinfo.h Add first fixes for conformtest for POSIX2008 2012-02-26 21:32:56 -05:00
libc-diag.h Split DIAG_* macros to new header libc-diag.h. 2017-02-25 09:59:46 -05:00
libc-internal.h Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
libc-pointer-arith.h Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
libc-symbols.h Deprecate libnsl by default (only shared library will be 2017-03-21 15:14:27 +01:00
libgen.h
libintl.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
libio.h Rename bits/stdio-lock.h to stdio-lock.h (bug 14912). 2015-09-04 16:21:14 +00:00
limits.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
link.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
list.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
locale.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
malloc.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
math.h Add roundeven, roundevenf, roundevenl. 2016-12-21 01:48:27 +00:00
mcheck.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
memory.h
mntent.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
monetary.h Add first fixes for conformtest for POSIX2008 2012-02-26 21:32:56 -05:00
mqueue.h Fix mq_receive, mq_send mq_timed* namespace (bug 18545). 2015-06-17 20:19:04 +00:00
netdb.h Fix h_errno namespace (bug 18520). 2015-06-12 10:10:18 +00:00
netgroup.h
nl_types.h
nss.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
nsswitch.h
obstack.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
poll.h
printf.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
pthread.h Fix mq_notify pthread_barrier_* namespace (bug 18544). 2015-06-17 20:16:56 +00:00
pty.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
pwd.h Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724] 2015-10-02 11:34:13 +02:00
regex.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
resolv.h resolv: Turn historic name lookup functions into compat symbols 2016-12-30 18:43:04 +01:00
rounding-mode.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
sched.h posix: New Linux posix_spawn{p} implementation 2016-03-07 11:53:47 +07:00
scratch_buffer.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
search.h Fix sem_* tdelete, tfind, tsearch, twalk namespace (bug 18536). 2015-06-17 20:11:58 +00:00
set-hooks.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
setjmp.h Mark internal setjmp functions hidden 2015-10-15 14:22:25 -07:00
sgtty.h
shadow.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
shlib-compat.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
signal.h Mark ld.so internel sigaction functions hidden 2015-10-15 14:23:31 -07:00
spawn.h
stab.h
stackinfo.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
stap-probe.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
stdc-predef.h Bug 20313: Update to Unicode 9.0.0 2017-02-21 06:30:38 -05:00
stdio_ext.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
stdio.h getopt: clean up error reporting 2017-04-07 07:48:57 -04:00
stdlib.h Remove the str(n)dup inlines from string/bits/string2.h. Although inlining 2017-03-13 18:45:42 +00:00
string.h Clean up redundancies between string.h and strings.h. 2017-02-16 17:02:50 -05:00
strings.h
stropts.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
stubs-prologue.h
syscall.h
sysexits.h
syslog.h
tar.h
termios.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
tgmath.h
time.h timezone: Remove TZNAME_MAX limit from sysconf [BZ #15576] 2017-03-07 17:45:38 +01:00
ttyent.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
uchar.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
ucontext.h
ulimit.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
unistd.h Fix hurd __access_noerrno implementation. 2016-11-18 16:49:08 -02:00
utime.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
utmp.h Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
values.h Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
wchar.h Use __typeof instead of typeof 2016-06-04 09:19:09 +02:00
wctype.h Fix regex wctype namespace (bug 18495). 2015-06-05 20:04:47 +00:00
wordexp.h First steps to get conformtest fully working 2012-02-25 23:18:39 -05:00
xlocale.h