zephyr/lib/libc/minimal/source/stdout/sprintf.c

103 lines
1.8 KiB
C

/* sprintf.c */
/*
* Copyright (c) 1997-2010, 2013-2014 Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdarg.h>
#include <stdio.h>
extern int _prf(int (*func)(), void *dest,
const char *format, va_list vargs);
struct emitter {
char *ptr;
int len;
};
static int sprintf_out(int c, struct emitter *p)
{
if (p->len > 1) { /* need to reserve a byte for EOS */
*(p->ptr) = c;
p->ptr += 1;
p->len -= 1;
}
return 0; /* indicate keep going so we get the total count */
}
int snprintf(char *_Restrict s, size_t len, const char *_Restrict format, ...)
{
va_list vargs;
struct emitter p;
int r;
char dummy;
if (len == 0) {
s = &dummy; /* write final NUL to dummy, can't change *s */
}
p.ptr = s;
p.len = (int) len;
va_start(vargs, format);
r = _prf(sprintf_out, (void *) (&p), format, vargs);
va_end(vargs);
*(p.ptr) = 0;
return r;
}
int sprintf(char *_Restrict s, const char *_Restrict format, ...)
{
va_list vargs;
struct emitter p;
int r;
p.ptr = s;
p.len = (int) 0x7fffffff; /* allow up to "maxint" characters */
va_start(vargs, format);
r = _prf(sprintf_out, (void *) (&p), format, vargs);
va_end(vargs);
*(p.ptr) = 0;
return r;
}
int vsnprintf(char *_Restrict s, size_t len, const char *_Restrict format, va_list vargs)
{
struct emitter p;
int r;
char dummy;
if (len == 0) {
s = &dummy; /* write final NUL to dummy, can't change * *s */
}
p.ptr = s;
p.len = (int) len;
r = _prf(sprintf_out, (void *) (&p), format, vargs);
*(p.ptr) = 0;
return r;
}
int vsprintf(char *_Restrict s, const char *_Restrict format, va_list vargs)
{
struct emitter p;
int r;
p.ptr = s;
p.len = (int) 0x7fffffff; /* allow up to "maxint" characters */
r = _prf(sprintf_out, (void *) (&p), format, vargs);
*(p.ptr) = 0;
return r;
}