Re: [PATCH v3] gettext.c: detect the vsnprintf bug at runtime

From: Trần Ngọc Quân <vnwildman@gmail.com>
Date: Dec 2, 2013, 07:40 UTC
Message-ID: <529C3987.7070708@gmail.com>
In-Reply-To: <CACsJy8B5aBGnm=04y60W1XVovHVryP1Co0_mmgV0f7Ox13aGjw@mail.gmail.com>

On 02/12/2013 12:57, Duy Nguyen wrote:

Show 10 quoted lines

>> I suggest use C preprocessor instead. The person who complete git (make debian, rpm etc. package) decide  enable it or not (disable by default). Most of people use git from distribution instead of complete it from source.
>>
>> #ifndef VSNPRINTF_OK
>>         setlocale(LC_CTYPE, "C");
>> #endif
>>
> A single vsnprintf is cheap enough that I would not worry about
> performance impact. Given a choice between this and distro
> maintainers, some of them do check release notes, some not so much,
> I'd rather go with this.

We can set this macro automatically by using autoconf. Add following code in configure.ac

AC_LANG_CONFTEST( [AC_LANG_PROGRAM([[ #include <stdio.h> #include <locale.h> #include <gnu/libc-version.h>

#define STR "David_K\345gedal"
]],[[
    char buf[20];
    setlocale(LC_ALL, "en_US.UTF-8");
    if (snprintf(buf, 13, "%.13s", STR) < 0){
        printf("0");
    }else{
        printf("1");
    }
]])])
gcc -o conftest conftest.c
AC_DEFINE([VSNPRINTF_OK], [m4_esyscmd([./conftest])], [Enable l10n libc
if vnsprintf OK])

You can change c code here!

-- 
Trần Ngọc Quân.