rockbox/firmware/include/vuprintf.h

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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Felix Arends
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef __VUPRINTF_H__
#define __VUPRINTF_H__
#include <stdarg.h>
/* callback function is called for every output character (byte) in the
* output with userp
*
* it must return > 0 to continue (increments counter)
* it may return 0 to stop (increments counter)
* it may return < 0 to stop (does not increment counter)
* a zero in the format string stops (does not increment counter)
*
* caller is reponsible for stopping formatting in order to keep the return
* value from overflowing (assuming they have a reason to care)
*/
typedef int (* vuprintf_push_cb)(void *userp, int c);
/*
* returns the number of times push() was called and returned >= 0
*/
int vuprintf(vuprintf_push_cb push, void *userp, const char *fmt, va_list ap);
#endif /* __VUPRINTF_H__ */