Re: [PATCH] posix: Fix getconf symbolic constants defined in limits.h (BZ# 29147)

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

Ping (x3).

On 09/02/23 16:43, Adhemerval Zanella Netto wrote:
> Ping (x2).
> 
> On 08/08/22 10:33, Adhemerval Zanella Netto wrote:
>> Ping.
>>
>> On 27/05/22 11:31, Adhemerval Zanella wrote:
>>> POSIX-1.2018 defines that getconf utility shall print symbolic constant
>>> listed under the heading Maximum value and Minimum Values [1], however
>>> current behaviour is to print the values using pathconf or sysconf,
>>> which represents the specific implementation values instead of the
>>> system agnostics ones.
>>>
>>> Another issue is for such the symbolic constants, getconf handles them
>>> as a path_var which requires an additional pathname (which does not
>>> make sense for constants values).
>>>
>>> The patch fixes it adding a new internal type, LIMITS_H, which only
>>> prints the constant symbolic without requiring an additional path.
>>> Only the values define in glibc provided limits.h plust the GNU
>>> extensions are handled.
>>>
>>> Checked on x86_64-linux-gnu.
>>>
>>> [1] https://pubs.opengroup.org/onlinepubs/9699919799/utilities/getconf.html)
>>> ---
>>>  posix/Makefile              | 12 ++++++
>>>  posix/getconf.c             | 86 +++++++++++++++++++++++++++++--------
>>>  posix/tst-getconf-limits.py | 72 +++++++++++++++++++++++++++++++
>>>  3 files changed, 153 insertions(+), 17 deletions(-)
>>>  create mode 100755 posix/tst-getconf-limits.py
>>>
>>> diff --git a/posix/Makefile b/posix/Makefile
>>> index cfebb8ef06..a21c462e9e 100644
>>> --- a/posix/Makefile
>>> +++ b/posix/Makefile
>>> @@ -175,6 +175,8 @@ tests-special += $(objpfx)bug-regex2-mem.out $(objpfx)bug-regex14-mem.out \
>>>  		 $(objpfx)bug-glob2-mem.out $(objpfx)tst-vfork3-mem.out \
>>>  		 $(objpfx)tst-fnmatch-mem.out $(objpfx)bug-regex36-mem.out \
>>>  		 $(objpfx)tst-glob-tilde-mem.out $(objpfx)bug-ga2-mem.out
>>> +
>>> +tests-special += $(objpfx)tst-getconf-limits.out
>>>  endif
>>>  
>>>  include ../Rules
>>> @@ -404,6 +406,16 @@ $(objpfx)tst-getconf.out: tst-getconf.sh $(objpfx)getconf
>>>  	$(SHELL) $< $(common-objpfx) '$(built-program-cmd)'; \
>>>  	$(evaluate-test)
>>>  
>>> +$(objpfx)tst-getconf-limits.out: tst-getconf-limits.py $(objpfx)getconf
>>> +	PYTHONPATH=../scripts \
>>> +	$(PYTHON) tst-getconf-limits.py \
>>> +		   --cc="$(CC) $(patsubst -DMODULE_NAME=%, \
>>> +					  -DMODULE_NAME=testsuite, \
>>> +					  $(CPPFLAGS)) -D_ISOMAC" \
>>> +		   '$(built-program-cmd)' \
>>> +	< /dev/null > $@ 2>&1; $(evaluate-test)
>>> +
>>> +
>>>  $(objpfx)bug-ga2-mem.out: $(objpfx)bug-ga2.out
>>>  	{ test -r $(objpfx)bug-ga2.mtrace \
>>>  	|| ( echo "bug-ga2.mtrace does not exist"; exit 77; ) \
>>> diff --git a/posix/getconf.c b/posix/getconf.c
>>> index a1adbc4b50..ffd0db234b 100644
>>> --- a/posix/getconf.c
>>> +++ b/posix/getconf.c
>>> @@ -49,24 +49,18 @@
>>>  struct conf
>>>    {
>>>      const char *name;
>>> -    const int call_name;
>>> -    const enum { SYSCONF, CONFSTR, PATHCONF } call;
>>> +    const long int call_name;
>>> +    const enum { SYSCONF, CONFSTR, PATHCONF, LIMITS_H } call;
>>>    };
>>>  
>>>  static const struct conf vars[] =
>>>    {
>>>      { "LINK_MAX", _PC_LINK_MAX, PATHCONF },
>>> -    { "_POSIX_LINK_MAX", _PC_LINK_MAX, PATHCONF },
>>>      { "MAX_CANON", _PC_MAX_CANON, PATHCONF },
>>> -    { "_POSIX_MAX_CANON", _PC_MAX_CANON, PATHCONF },
>>>      { "MAX_INPUT", _PC_MAX_INPUT, PATHCONF },
>>> -    { "_POSIX_MAX_INPUT", _PC_MAX_INPUT, PATHCONF },
>>>      { "NAME_MAX", _PC_NAME_MAX, PATHCONF },
>>> -    { "_POSIX_NAME_MAX", _PC_NAME_MAX, PATHCONF },
>>>      { "PATH_MAX", _PC_PATH_MAX, PATHCONF },
>>> -    { "_POSIX_PATH_MAX", _PC_PATH_MAX, PATHCONF },
>>>      { "PIPE_BUF", _PC_PIPE_BUF, PATHCONF },
>>> -    { "_POSIX_PIPE_BUF", _PC_PIPE_BUF, PATHCONF },
>>>      { "SOCK_MAXBUF", _PC_SOCK_MAXBUF, PATHCONF },
>>>      { "_POSIX_ASYNC_IO", _PC_ASYNC_IO, PATHCONF },
>>>      { "_POSIX_CHOWN_RESTRICTED", _PC_CHOWN_RESTRICTED, PATHCONF },
>>> @@ -123,9 +117,7 @@ static const struct conf vars[] =
>>>      { "_NPROCESSORS_CONF", _SC_NPROCESSORS_CONF, SYSCONF },
>>>      { "_NPROCESSORS_ONLN", _SC_NPROCESSORS_ONLN, SYSCONF },
>>>      { "_PHYS_PAGES", _SC_PHYS_PAGES, SYSCONF },
>>> -    { "_POSIX_ARG_MAX", _SC_ARG_MAX, SYSCONF },
>>>      { "_POSIX_ASYNCHRONOUS_IO", _SC_ASYNCHRONOUS_IO, SYSCONF },
>>> -    { "_POSIX_CHILD_MAX", _SC_CHILD_MAX, SYSCONF },
>>>      { "_POSIX_FSYNC", _SC_FSYNC, SYSCONF },
>>>      { "_POSIX_JOB_CONTROL", _SC_JOB_CONTROL, SYSCONF },
>>>      { "_POSIX_MAPPED_FILES", _SC_MAPPED_FILES, SYSCONF },
>>> @@ -133,8 +125,6 @@ static const struct conf vars[] =
>>>      { "_POSIX_MEMLOCK_RANGE", _SC_MEMLOCK_RANGE, SYSCONF },
>>>      { "_POSIX_MEMORY_PROTECTION", _SC_MEMORY_PROTECTION, SYSCONF },
>>>      { "_POSIX_MESSAGE_PASSING", _SC_MESSAGE_PASSING, SYSCONF },
>>> -    { "_POSIX_NGROUPS_MAX", _SC_NGROUPS_MAX, SYSCONF },
>>> -    { "_POSIX_OPEN_MAX", _SC_OPEN_MAX, SYSCONF },
>>>      { "_POSIX_PII", _SC_PII, SYSCONF },
>>>      { "_POSIX_PII_INTERNET", _SC_PII_INTERNET, SYSCONF },
>>>      { "_POSIX_PII_INTERNET_DGRAM", _SC_PII_INTERNET_DGRAM, SYSCONF },
>>> @@ -153,8 +143,6 @@ static const struct conf vars[] =
>>>      { "_POSIX_SELECT", _SC_SELECT, SYSCONF },
>>>      { "_POSIX_SEMAPHORES", _SC_SEMAPHORES, SYSCONF },
>>>      { "_POSIX_SHARED_MEMORY_OBJECTS", _SC_SHARED_MEMORY_OBJECTS, SYSCONF },
>>> -    { "_POSIX_SSIZE_MAX", _SC_SSIZE_MAX, SYSCONF },
>>> -    { "_POSIX_STREAM_MAX", _SC_STREAM_MAX, SYSCONF },
>>>      { "_POSIX_SYNCHRONIZED_IO", _SC_SYNCHRONIZED_IO, SYSCONF },
>>>      { "_POSIX_THREADS", _SC_THREADS, SYSCONF },
>>>      { "_POSIX_THREAD_ATTR_STACKADDR", _SC_THREAD_ATTR_STACKADDR, SYSCONF },
>>> @@ -170,7 +158,6 @@ static const struct conf vars[] =
>>>      { "_POSIX_THREAD_SAFE_FUNCTIONS", _SC_THREAD_SAFE_FUNCTIONS, SYSCONF },
>>>      { "_POSIX_TIMERS", _SC_TIMERS, SYSCONF },
>>>      { "TIMER_MAX", _SC_TIMER_MAX, SYSCONF },
>>> -    { "_POSIX_TZNAME_MAX", _SC_TZNAME_MAX, SYSCONF },
>>>      { "_POSIX_VERSION", _SC_VERSION, SYSCONF },
>>>      { "_T_IOV_MAX", _SC_T_IOV_MAX, SYSCONF },
>>>      { "_XOPEN_CRYPT", _SC_XOPEN_CRYPT, SYSCONF },
>>> @@ -207,7 +194,6 @@ static const struct conf vars[] =
>>>      { "POSIX2_EXPR_NEST_MAX", _SC_EXPR_NEST_MAX, SYSCONF },
>>>      { "POSIX2_FORT_DEV", _SC_2_FORT_DEV, SYSCONF },
>>>      { "POSIX2_FORT_RUN", _SC_2_FORT_RUN, SYSCONF },
>>> -    { "_POSIX2_LINE_MAX", _SC_LINE_MAX, SYSCONF },
>>>      { "POSIX2_LINE_MAX", _SC_LINE_MAX, SYSCONF },
>>>      { "POSIX2_LOCALEDEF", _SC_2_LOCALEDEF, SYSCONF },
>>>      { "POSIX2_RE_DUP_MAX", _SC_RE_DUP_MAX, SYSCONF },
>>> @@ -403,6 +389,63 @@ static const struct conf vars[] =
>>>      { "_POSIX_IPV6", _SC_IPV6, SYSCONF },
>>>      { "_POSIX_RAW_SOCKETS", _SC_RAW_SOCKETS, SYSCONF },
>>>  
>>> +    /* limits.h symbolic constants.  */
>>> +#define DEF_LIMIT_H(name) { #name, name, LIMITS_H }
>>> +    /* Maximum Values.  */
>>> +    DEF_LIMIT_H (_POSIX_CLOCKRES_MIN),
>>> +
>>> +    /* Minimum Values.  */
>>> +    DEF_LIMIT_H (_POSIX_AIO_LISTIO_MAX),
>>> +    DEF_LIMIT_H (_POSIX_AIO_MAX),
>>> +    DEF_LIMIT_H (_POSIX_ARG_MAX),
>>> +    DEF_LIMIT_H (_POSIX_CHILD_MAX),
>>> +    DEF_LIMIT_H (_POSIX_DELAYTIMER_MAX),
>>> +    DEF_LIMIT_H (_POSIX_HOST_NAME_MAX),
>>> +    DEF_LIMIT_H (_POSIX_LINK_MAX),
>>> +    DEF_LIMIT_H (_POSIX_LOGIN_NAME_MAX),
>>> +    DEF_LIMIT_H (_POSIX_MAX_CANON),
>>> +    DEF_LIMIT_H (_POSIX_MAX_INPUT),
>>> +    DEF_LIMIT_H (_POSIX_MQ_OPEN_MAX),
>>> +    DEF_LIMIT_H (_POSIX_MQ_PRIO_MAX),
>>> +    DEF_LIMIT_H (_POSIX_NAME_MAX),
>>> +    DEF_LIMIT_H (_POSIX_NGROUPS_MAX),
>>> +    DEF_LIMIT_H (_POSIX_OPEN_MAX),
>>> +    DEF_LIMIT_H (_POSIX_PATH_MAX),
>>> +    DEF_LIMIT_H (_POSIX_PIPE_BUF),
>>> +    DEF_LIMIT_H (_POSIX_RE_DUP_MAX),
>>> +    DEF_LIMIT_H (_POSIX_RTSIG_MAX),
>>> +    DEF_LIMIT_H (_POSIX_SEM_NSEMS_MAX),
>>> +    DEF_LIMIT_H (_POSIX_SEM_VALUE_MAX),
>>> +    DEF_LIMIT_H (_POSIX_SIGQUEUE_MAX),
>>> +    DEF_LIMIT_H (_POSIX_SSIZE_MAX),
>>> +    DEF_LIMIT_H (_POSIX_STREAM_MAX),
>>> +    DEF_LIMIT_H (_POSIX_SYMLINK_MAX),
>>> +    DEF_LIMIT_H (_POSIX_SYMLOOP_MAX),
>>> +    DEF_LIMIT_H (_POSIX_THREAD_DESTRUCTOR_ITERATIONS),
>>> +    DEF_LIMIT_H (_POSIX_THREAD_KEYS_MAX),
>>> +    DEF_LIMIT_H (_POSIX_THREAD_THREADS_MAX),
>>> +    DEF_LIMIT_H (_POSIX_TIMER_MAX),
>>> +    DEF_LIMIT_H (_POSIX_TTY_NAME_MAX),
>>> +    DEF_LIMIT_H (_POSIX_TZNAME_MAX),
>>> +
>>> +    DEF_LIMIT_H (_POSIX2_BC_BASE_MAX),
>>> +    DEF_LIMIT_H (_POSIX2_BC_DIM_MAX),
>>> +    DEF_LIMIT_H (_POSIX2_BC_SCALE_MAX),
>>> +    DEF_LIMIT_H (_POSIX2_BC_STRING_MAX),
>>> +    DEF_LIMIT_H (_POSIX2_CHARCLASS_NAME_MAX),
>>> +    DEF_LIMIT_H (_POSIX2_COLL_WEIGHTS_MAX),
>>> +    DEF_LIMIT_H (_POSIX2_EXPR_NEST_MAX),
>>> +    DEF_LIMIT_H (_POSIX2_LINE_MAX),
>>> +    DEF_LIMIT_H (_POSIX2_RE_DUP_MAX),
>>> +
>>> +    DEF_LIMIT_H (_XOPEN_IOV_MAX),
>>> +
>>> +    /* GNU extensions.  */
>>> +    DEF_LIMIT_H (_POSIX_FD_SETSIZE),
>>> +    DEF_LIMIT_H (_POSIX_HIWAT),
>>> +    DEF_LIMIT_H (_POSIX_QLIMIT),
>>> +    DEF_LIMIT_H (_POSIX_UIO_MAXIOV),
>>> +
>>>      { NULL, 0, SYSCONF }
>>>    };
>>>  
>>> @@ -430,7 +473,7 @@ print_all (const char *path)
>>>    long int value;
>>>    char *cvalue;
>>>    for (c = vars; c->name != NULL; ++c) {
>>> -    printf("%-35s", c->name);
>>> +    printf("%-36s", c->name);
>>>      switch (c->call) {
>>>        case PATHCONF:
>>>  	value = pathconf (path, c->call_name);
>>> @@ -461,6 +504,9 @@ print_all (const char *path)
>>>  	printf ("%.*s\n", (int) clen, cvalue);
>>>  	free (cvalue);
>>>  	break;
>>> +      case LIMITS_H:
>>> +	printf ("%ld\n", c->call_name);
>>> +	break;
>>>      }
>>>    }
>>>    exit (0);
>>> @@ -701,6 +747,12 @@ environment SPEC.\n\n"));
>>>  
>>>  	    printf ("%.*s\n", (int) clen, cvalue);
>>>  	    exit (0);
>>> +
>>> +	  case LIMITS_H:
>>> +	    if (argc - ai > 1)
>>> +	      usage ();
>>> +	    printf ("%ld\n", c->call_name);
>>> +	    exit (0);
>>>  	  }
>>>        }
>>>  
>>> diff --git a/posix/tst-getconf-limits.py b/posix/tst-getconf-limits.py
>>> new file mode 100755
>>> index 0000000000..b64b02f134
>>> --- /dev/null
>>> +++ b/posix/tst-getconf-limits.py
>>> @@ -0,0 +1,72 @@
>>> +#!/usr/bin/python3
>>> +#
>>> +# Test if getconf returns the symbolic constants defined in limits.h.
>>> +# Copyright (C) 2020-2022 Free Software Foundation, Inc.
>>> +# This file is part of the GNU C Library.
>>> +#
>>> +# The GNU C Library 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.
>>> +#
>>> +# The GNU C Library 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 the GNU C Library; if not, see
>>> +# <https://www.gnu.org/licenses/>.
>>> +
>>> +import argparse
>>> +import glibcextract
>>> +import re
>>> +import subprocess
>>> +import sys
>>> +
>>> +
>>> +def parse_getconf(cmd):
>>> +    getconf_out = subprocess.run(cmd + ['-a'], stdout=subprocess.PIPE,
>>> +                                 check=True, universal_newlines=True).stdout
>>> +    getconf_set = {}
>>> +    for line in getconf_out.splitlines():
>>> +        fields = line.split()
>>> +        if len(fields) == 2:
>>> +            getconf_set[fields[0]] = fields[1]
>>> +    return getconf_set
>>> +
>>> +
>>> +def main():
>>> +    """The main entry point."""
>>> +    parser = argparse.ArgumentParser(
>>> +        description='Test if getconf returns the symbolic constants defined '
>>> +        'in limits.h.')
>>> +    parser.add_argument('--cc', metavar='CC',
>>> +                        help='C compiler (including options) to use')
>>> +    parser.add_argument('cmd',
>>> +                        help='How to run getconf')
>>> +    args = parser.parse_args()
>>> +
>>> +    ctes = glibcextract.compute_macro_consts(
>>> +            source_text='#include <limits.h>\n',
>>> +            cc=args.cc,
>>> +            macro_re='_POSIX.*',
>>> +            exclude_re='_POSIX_C_SOURCE|_POSIX_SOURCE')
>>> +
>>> +    getconf_ctes = parse_getconf (args.cmd.split())
>>> +
>>> +    ret = 0
>>> +    for cte,value in ctes.items():
>>> +        if cte in getconf_ctes:
>>> +            if getconf_ctes[cte] != value:
>>> +                print('Symbol {} is defined as {} on limits.h but getconf shows {}'
>>> +                      .format(cte, value, getconf_ctes[cte]))
>>> +                ret = 1;
>>> +        else:
>>> +            print('Symbol {} not presented in getconf'.format(cte))
>>> +            ret = 1;
>>> +    sys.exit(ret)
>>> +
>>> +
>>> +if __name__ == '__main__':
>>> +    main()