/*
* Copyright (c) 2006 Josef Cejka
* Copyright (c) 2025 Jiří Zárevúcky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup libc
* @{
*/
/** @file
*/
#include <errno.h>
#include <macros.h>
#include <printf_core.h>
#include <stdarg.h>
#include <stdio.h>
#include <str.h>
typedef struct {
char *dst; /* Destination */
size_t left;
} vsnprintf_data_t;
static int vsnprintf_str_write(const char *str, size_t size, void *data)
{
vsnprintf_data_t *d = data;
size_t left = min(size, d->left);
if (left > 0) {
memcpy(d->dst, str, left);
d->dst += left;
d->left -= left;
}
return EOK;
}
int vsnprintf(char *str, size_t size, const char *fmt, va_list ap)
{
vsnprintf_data_t data = {
.dst = str,
.left = size ? size - 1 : 0,
};
printf_spec_t ps = {
vsnprintf_str_write,
&data
};
int written = printf_core(fmt, &ps, ap);
if (written < 0)
return written;
/* Write the terminating NUL character. */
if (size > 0)
data.dst[0] = 0;
return written;
}
/** @}
*/