newlib-cygwin/newlib/libc/stdio/asniprintf.c

107 lines
2.3 KiB
C

/* Copyright (C) 2007, 2008 Eric Blake
* Permission to use, copy, modify, and distribute this software
* is freely granted, provided that this notice is preserved.
*/
/* This code was derived from asprintf.c */
/* doc in siprintf.c */
#include <_ansi.h>
#include <reent.h>
#include <stdio.h>
#include <stdarg.h>
#include <limits.h>
#include <errno.h>
#include "local.h"
char *
_asniprintf_r (struct _reent *ptr,
char *buf,
size_t *lenp,
const char *fmt, ...)
{
int ret;
va_list ap;
FILE f;
size_t len = *lenp;
if (buf && len)
{
/* mark an existing buffer, but allow allocation of larger string */
f._flags = __SWR | __SSTR | __SOPT;
}
else
{
/* mark a zero-length reallocatable buffer */
f._flags = __SWR | __SSTR | __SMBF;
len = 0;
buf = NULL;
}
f._bf._base = f._p = (unsigned char *) buf;
/* For now, inherit the 32-bit signed limit of FILE._bf._size.
FIXME - it would be nice to rewrite sys/reent.h to support size_t
for _size. */
if (len > INT_MAX)
{
_REENT_ERRNO(ptr) = EOVERFLOW;
return NULL;
}
f._bf._size = f._w = len;
f._file = -1; /* No file. */
va_start (ap, fmt);
ret = _svfiprintf_r (ptr, &f, fmt, ap);
va_end (ap);
if (ret < 0)
return NULL;
*lenp = ret;
*f._p = '\0';
return (char *) f._bf._base;
}
#ifndef _REENT_ONLY
char *
asniprintf (char *buf,
size_t *lenp,
const char *fmt, ...)
{
int ret;
va_list ap;
FILE f;
size_t len = *lenp;
struct _reent *ptr = _REENT;
if (buf && len)
{
/* mark an existing buffer, but allow allocation of larger string */
f._flags = __SWR | __SSTR | __SOPT;
}
else
{
/* mark a zero-length reallocatable buffer */
f._flags = __SWR | __SSTR | __SMBF;
len = 0;
buf = NULL;
}
f._bf._base = f._p = (unsigned char *) buf;
/* For now, inherit the 32-bit signed limit of FILE._bf._size.
FIXME - it would be nice to rewrite sys/reent.h to support size_t
for _size. */
if (len > INT_MAX)
{
_REENT_ERRNO(ptr) = EOVERFLOW;
return NULL;
}
f._bf._size = f._w = len;
f._file = -1; /* No file. */
va_start (ap, fmt);
ret = _svfiprintf_r (ptr, &f, fmt, ap);
va_end (ap);
if (ret < 0)
return NULL;
*lenp = ret;
*f._p = '\0';
return (char *) f._bf._base;
}
#endif /* ! _REENT_ONLY */