Re: use of thread-unsafe localeconv in vasprintf

[Simon Josefsson]

Simon Josefsson <address@hidden> writes:

> In gsasl I have a script that try to help me make sure I don't use
> thread unsafe functions (included below for reference), and after
> updating gnulib for it, it triggers on vasnprintf.c:
>
> ../lib/gl/vasnprintf.c:#include <locale.h>      /* localeconv() */
> ../lib/gl/vasnprintf.c:                             localeconv () -> 
> decimal_point;
> ../lib/gl/vasnprintf.c:                             localeconv () -> 
> decimal_point;
>
> According to:
>
> http://www.opengroup.org/onlinepubs/009695399/functions/localeconv.html
>
> "The localeconv() function need not be reentrant. A function that is
> not required to be reentrant is not required to be thread-safe."
>
> Is there a thread-safe replacement for localeconv?  If not, can we
> install something like the patch below, to allow thread-safe
> vasnprintf?

Any objections to installing this patch?

I searched a little, but could not find any thread-safe replacement
for localeconv standardized anywhere, so I guess disabling it is the
only option.

/Simon

> --- vasnprintf.c      12 Mar 2007 12:41:12 +0100      1.28
> +++ vasnprintf.c      17 Mar 2007 13:29:42 +0100      
> @@ -34,7 +34,9 @@
>  # include "vasnprintf.h"
>  #endif
>  
> +#if !DONT_USE_LOCALECONV
>  #include <locale.h>  /* localeconv() */
> +#endif
>  #include <stdio.h>   /* snprintf(), sprintf() */
>  #include <stdlib.h>  /* abort(), malloc(), realloc(), free() */
>  #include <string.h>  /* memcpy(), strlen() */
> @@ -497,8 +499,10 @@
>                             if ((flags & FLAG_ALT)
>                                 || mantissa > 0.0L || precision > 0)
>                               {
> -                               const char *point =
> -                                 localeconv () -> decimal_point;
> +                               const char *point = ".";
> +#if !DONT_USE_LOCALECONV
> +                               point = localeconv () -> decimal_point;
> +#endif
>                                 /* The decimal point is always a single byte:
>                                    either '.' or ','.  */
>                                 *p++ = (point[0] != '\0' ? point[0] : '.');
> @@ -645,8 +649,10 @@
>                             if ((flags & FLAG_ALT)
>                                 || mantissa > 0.0 || precision > 0)
>                               {
> -                               const char *point =
> -                                 localeconv () -> decimal_point;
> +                               const char *point = ".";
> +#if !DONT_USE_LOCALECONV
> +                               point = localeconv () -> decimal_point;
> +#endif
>                                 /* The decimal point is always a single byte:
>                                    either '.' or ','.  */
>                                 *p++ = (point[0] != '\0' ? point[0] : '.');
>
> /Simon
>
> #!/bin/sh
>
> # Copyright (C) 2004, 2005 Simon Josefsson
> #
> # This file is free software; you can redistribute it and/or modify it
> # under the terms of the GNU General Public License as published by
> # the Free Software Foundation; either version 2, 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
> # General Public License for more details.
> #
> # You should have received a copy of the GNU General Public License
> # along with this file; if not, write to the Free Software Foundation,
> # Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
>
> FILES="$@"
> FILES=${FILES:-$THREADSAFETY_FILES}
>
> if test -z "$FILES"; then
>     echo "Usage: $0 [FILE...]"
>     exit 1
> fi
>
> # http://www.opengroup.org/onlinepubs/009695399/functions/xsh_chap02_09.html
> UNSAFE="asctime basename catgets crypt ctime dbm_clearerr dbm_close 
> dbm_delete dbm_error dbm_fetch dbm_firstkey dbm_nextkey dbm_open dbm_store 
> dirname dlerror drand48 ecvt encrypt endgrent endpwent endutxent fcvt ftw 
> gcvt getc_unlocked getchar_unlocked getdate getenv getgrent getgrgid getgrnam 
> gethostbyaddr gethostbyname gethostent getlogin getnetbyaddr getnetbyname 
> getnetent getopt getprotobyname getprotobynumber getprotoent getpwent 
> getpwnam getpwuid getservbyname getservbyport getservent getutxent getutxid 
> getutxline gmtime hcreate hdestroy hsearch inet_ntoa l64a lgamma lgammaf 
> lgammal localeconv localtime lrand48 mrand48 nftw nl_langinfo ptsname 
> putc_unlocked putchar_unlocked putenv pututxline rand readdir setenv setgrent 
> setkey setpwent setutxent strerror strtok ttyname unsetenv wcstombs wctomb"
>
> set -- $UNSAFE
> cmd="-e [^_0-9a-z]($1"
> shift
> while test "$1"; do
>     cmd="${cmd}|$1"
>     shift
> done
> cmd="${cmd})[^_0-9a-z]*\("
>
> if egrep $cmd $FILES; then
>     exit 1
> fi
>
> exit 0