mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-01 17:30:07 +00:00
04277e02d7
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
85 lines
2.0 KiB
C
85 lines
2.0 KiB
C
/* Printf Extension Example
|
|
Copyright (C) 1991-2019 Free Software Foundation, Inc.
|
|
|
|
This program 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
|
|
of the License, or (at your option) any later version.
|
|
|
|
This program 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 program; if not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <printf.h>
|
|
|
|
/*@group*/
|
|
typedef struct
|
|
{
|
|
char *name;
|
|
}
|
|
Widget;
|
|
/*@end group*/
|
|
|
|
int
|
|
print_widget (FILE *stream,
|
|
const struct printf_info *info,
|
|
const void *const *args)
|
|
{
|
|
const Widget *w;
|
|
char *buffer;
|
|
int len;
|
|
|
|
/* Format the output into a string. */
|
|
w = *((const Widget **) (args[0]));
|
|
len = asprintf (&buffer, "<Widget %p: %s>", w, w->name);
|
|
if (len == -1)
|
|
return -1;
|
|
|
|
/* Pad to the minimum field width and print to the stream. */
|
|
len = fprintf (stream, "%*s",
|
|
(info->left ? -info->width : info->width),
|
|
buffer);
|
|
|
|
/* Clean up and return. */
|
|
free (buffer);
|
|
return len;
|
|
}
|
|
|
|
|
|
int
|
|
print_widget_arginfo (const struct printf_info *info, size_t n,
|
|
int *argtypes)
|
|
{
|
|
/* We always take exactly one argument and this is a pointer to the
|
|
structure.. */
|
|
if (n > 0)
|
|
argtypes[0] = PA_POINTER;
|
|
return 1;
|
|
}
|
|
|
|
|
|
int
|
|
main (void)
|
|
{
|
|
/* Make a widget to print. */
|
|
Widget mywidget;
|
|
mywidget.name = "mywidget";
|
|
|
|
/* Register the print function for widgets. */
|
|
register_printf_function ('W', print_widget, print_widget_arginfo);
|
|
|
|
/* Now print the widget. */
|
|
printf ("|%W|\n", &mywidget);
|
|
printf ("|%35W|\n", &mywidget);
|
|
printf ("|%-35W|\n", &mywidget);
|
|
|
|
return 0;
|
|
}
|