Re: [PATCH] PRItime: wrap PRItime for better l10n compatibility

From: Jiang Xin <worldhello.net@gmail.com>
Date: Jul 19, 2017, 00:57 UTC
Message-ID: <CANYiYbFROuyXso2ZKuJWDp4cSwpBu=bNAbC-yZtEyDwkbUcAhQ@mail.gmail.com>
In-Reply-To: <xmqq60epfy27.fsf@gitster.mtv.corp.google.com>

2017-07-19 1:35 GMT+08:00 Junio C Hamano <gitster@pobox.com>:

Show 32 quoted lines

> Jiang Xin <worldhello.net@gmail.com> writes:
>
>>> Two potential issues are:
>>>
>>>  - After this patch, there still are quite a many
>>>
>>>         printf("time is %"PRItime" ...\n", timestamp)
>>>
>>>    so the burden on the programmers having to remember when it is
>>>    required to use format_raw_time() becomes unclear, and makes the
>>>    change/churn larger when an existing message needs to be marked
>>>    for translation.
>>>
>>>  - The static struct strbuf here is a cheap way to avoid leaks, but
>>>    at the same time it is unfriendly to threaded code.  We could
>>>    instead do:
>>>
>>>         void append_PRItime(struct strbuf *buf, timestamp_t time);
>>>
>>>    to fix that trivially, but the damage to the caller obviously is
>>>    much larger going this way.
>>>
>>
>> I wonder if we can replace the original %lu for timestamp with PRIuMAX
>> instead.  PRIuMAX works fine with gettext utils.
>
> I think the question can better be answered if we know how gettext
> tools special case PRIuMAX.  One thing that may be problematic is
> that timestamp can later become a signed type and use of one level
> of redirection in the current code via PRItime and via timestamp_t
> is a good way to keep such a transition much easier.  Reverting it
> to use PRIuMAX would make such a transition much harder.

Gettext handles macros such as PRIuMAX in commit 8b45c5df1 ("Add support for ISO C 99 <inttypes.h> format string directive macros.", 2002-07-23 12:33:13 +0000).

Macros such as PRIuMAX are hard coded, and we can not hack gettext easily and directly.

For example, some code in commit 8b45c5df1 (see: See: http://git.savannah.gnu.org/cgit/gettext.git/commit/?id=8b45c5df18e1976a1275297db73978bfe6144c7e):

    +/* 8a. Convert ISO C 99 section 7.8.1 format string directives to string
    +   literal placeholders.  */
    +
    +/* Test for an ISO C 99 section 7.8.1 format string directive.  */
    +static bool
    +is_inttypes_macro (name)
    +     const char *name;
    +{
    +  /* Syntax:
    +     P R I { d | i | o | u | x | X }
    +     { { | LEAST | FAST } { 8 | 16 | 32 | 64 } | MAX | PTR }  */
    +  if (name[0] == 'P' && name[1] == 'R' && name[2] == 'I')
    +    {
    +      name += 3;
    +      if (name[0] == 'd' || name[0] == 'i' || name[0] == 'o' ||
name[0] == 'u'
    +          || name[0] == 'x' || name[0] == 'X')
    +        {
    +          name += 1;
    +          if (name[0] == 'M' && name[1] == 'A' && name[2] == 'X'
    +              && name[3] == '\0')
    +            return true;
    +          if (name[0] == 'P' && name[1] == 'T' && name[2] == 'R'
    +              && name[3] == '\0')
    +            return true;
    +          if (name[0] == 'L' && name[1] == 'E' && name[2] == 'A'
    +              && name[3] == 'S' && name[4] == 'T')
    +            name += 5;
    +          else if (name[0] == 'F' && name[1] == 'A' && name[2] == 'S'
    +                   && name[3] == 'T')
    +            name += 4;
    +          if (name[0] == '8' && name[1] == '\0')
    +            return true;
    +          if (name[0] == '1' && name[1] == '6' && name[2] == '\0')
    +            return true;
    +          if (name[0] == '3' && name[1] == '2' && name[2] == '\0')
    +            return true;
    +          if (name[0] == '6' && name[1] == '4' && name[2] == '\0')
    +            return true;
    +        }
    +    }
    +  return false;
    +}

    + if (*format == '<')
        {
    -     if (*format == 'h')
    +     spec.c99_directives =
    +       (const char **)
    +       xrealloc (spec.c99_directives,
    +                 2 * (spec.c99_directives_count + 1)
    +                 * sizeof (const char *));
    +     spec.c99_directives[2 * spec.c99_directives_count] = format;
    +
    +     format++;
    +     /* Parse ISO C 99 section 7.8.1 format string directive.
    +        Syntax:
    +        P R I { d | i | o | u | x | X }
    +        { { | LEAST | FAST } { 8 | 16 | 32 | 64 } | MAX | PTR }  */
    +     if (*format != 'P')
    +       goto bad_format;
    +     format++;
    +     if (*format != 'R')
    +       goto bad_format;
    +     format++;
    +     if (*format != 'I')
    +       goto bad_format;
    +     format++;
    +
    +     switch (*format)
    +       {
    +       case 'i': case 'd':
    +         type = FAT_INTEGER;
    +         break;
    +       case 'u': case 'o': case 'x': case 'X':
    +         type = FAT_INTEGER | FAT_UNSIGNED;
    +         break;
    +       default:
    +         goto bad_format;
    +       }
    +     format++;
    +
    +     if (format[0] == 'M' && format[1] == 'A' && format[2] == 'X')
    +       {
    +         type |= FAT_SIZE_INTMAX_T;
    +         format += 3;
    +       }
    +     else if (format[0] == 'P' && format[1] == 'T' && format[2] == 'R')

-- 
Jiang Xin