[Fwd: glib integer formatting macros]

[Sebastian Wilhelmi <wilhelmi ira uka de>]

Hi, all

I've got a request from a user. What do you think? IMHO it sounds quite
reasonable. The syntax is not nice, but better than to get a warning
everytime. I only seem to remember, that there is a slight difference of
the formats for printf and scanf (due to the fact, that ellipse parameters
are always upcasted to long (double), when they are short,int (float)). My
K&R however states the opposite, does someone know, what ansi/iso
requires?

Bye, Sebastian

-- 
Sebastian Wilhelmi                   |            här ovanför alla molnen
mailto:wilhelmi@ira.uka.de           |      är himmlen så förunerligt blå
http://goethe.ira.uka.de/~wilhelmi   |

--------------------------------------------------------------------
Forwarded (slighly edited) message
--------------------------------------------------------------------


> Hi Sebastian,
> 
> it would be extremely nice if there was a platform-independent way of
> passing the glib-defined integer types (such as guint32, gint64 etc.) to
> printf(), scanf() and relatives. Currently, there is no way of doing
> this. Therefore, platform-specific code has to be written whenever one
> of the glib integer types is to be passed to printf or scanf. In my
> opinion, this definitely is a missing feature in glib.
> 
> Please find below a patch that resolves this issue. However, you might
> want to make sure that the definitions are correct for 32-bit machines,
> since I only have access to 64-bit machines here. Mainly, I am not sure
> whether "%lli" and "%llu" are valid format expressions.
> 
> With this patch, it is possible to write code such as:
> 
>   guint32 blah = 3;
>   printf ("Hello " G_GUINT32_FORMAT " you", blah);
> 
> Best regards,
> 
> -- Sascha
> 
> Sascha Brawer, sb@adasys.ch, http://www.coli.uni-sb.de/~brawer
> 
> % cvs -z3 diff -u
> cvs server: Diffing .
> Index: configure.in
> ===================================================================
> RCS file: /cvs/gnome/glib/configure.in,v
> retrieving revision 1.91
> diff -u -r1.91 configure.in
> --- configure.in 1999/02/27 00:25:58 1.91
> +++ configure.in 1999/03/08 14:42:48
> @@ -924,6 +924,8 @@
>     cat >>$outfile <<_______EOF
>  typedef signed $gint16 gint16;
>  typedef unsigned $gint16 guint16;
> +#define G_GINT16_FORMAT  $gint16_format
> +#define G_GUINT16_FORMAT $guint16_format
>  _______EOF
>   fi
> 
> @@ -932,6 +934,8 @@
>     cat >>$outfile <<_______EOF
>  typedef signed $gint32 gint32;
>  typedef unsigned $gint32 guint32;
> +#define G_GINT32_FORMAT  $gint32_format
> +#define G_GUINT32_FORMAT $guint32_format
>  _______EOF
>   fi
> 
> @@ -944,6 +948,8 @@
>  ${glib_extension}typedef unsigned $gint64 guint64;
> 
>  #define G_GINT64_CONSTANT(val) $gint64_constant
> +#define G_GINT64_FORMAT  $gint64_format
> +#define G_GUINT64_FORMAT $guint64_format
>  _______EOF
>   fi
> 
> @@ -1100,26 +1106,52 @@
>  fi
> 
>  case 2 in
> -$ac_cv_sizeof_short)  gint16=short;;
> -$ac_cv_sizeof_int)  gint16=int;;
> +$ac_cv_sizeof_short)
> +  gint16=short
> +  gint16_format='"%i"'
> +  guint16_format='"%u"'
> +  ;;
> +$ac_cv_sizeof_int)
> +  gint16=int
> +  gint16_format='"%i"'
> +  guint16_format='"%u"'
> +  ;;
>  esac
> +
>  case 4 in
> -$ac_cv_sizeof_short)  gint32=short;;
> -$ac_cv_sizeof_int)  gint32=int;;
> -$ac_cv_sizeof_long)  gint32=long;;
> +$ac_cv_sizeof_short)
> +  gint32=short
> +  gint32_format='"%i"'
> +  guint32_format='"%u"'
> +  ;;
> +$ac_cv_sizeof_int)
> +  gint32=int
> +  gint32_format='"%i"'
> +  guint32_format='"%u"'
> +  ;;
> +$ac_cv_sizeof_long)
> +  gint32=long
> +  gint32_format='"%li"'
> +  guint32_format='"%lu"'
> +  ;;
>  esac
> +
>  case 8 in
>  $ac_cv_sizeof_int)
>    gint64=int
>    glib_extension=
>    glib_warning_guard=
>    gint64_constant='(val)'
> +  gint64_format='"%i"'
> +  guint64_format='"%u"'
>    ;;
>  $ac_cv_sizeof_long)
>    gint64=long
>    glib_extension=
>    glib_warning_guard=
>    gint64_constant='(val##L)'
> +  gint64_format='"%li"'
> +  guint64_format='"%lu"'
>    ;;
>  $ac_cv_sizeof_long_long)
>    gint64='long long'
> @@ -1133,6 +1165,8 @@
> 
>  "
>    gint64_constant='(G_GNUC_EXTENSION (val##LL))'
> +  gint64_format='"%lli"'
> +  gint64_format='"%llu"'
>    ;;
>  esac