4
0
mirror of git://sourceware.org/git/newlib-cygwin.git synced 2025-01-21 05:49:19 +08:00
newlib-cygwin/newlib/libc/stdio/vasniprintf.c
Matt Joyce f3b8138239 Add _REENT_ERRNO(ptr)
Add a _REENT_ERRNO() macro to encapsulate the access to the
_errno member of struct reent. This will help to replace the
structure member with a thread-local storage object in a follow
up patch.

Replace uses of __errno_r() with _REENT_ERRNO().  Keep __errno_r() macro for
potential users outside of Newlib.
2022-07-13 06:55:41 +02:00

70 lines
1.5 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 viprintf.c */
#include <_ansi.h>
#include <reent.h>
#include <stdio.h>
#include <stdarg.h>
#include <limits.h>
#include <errno.h>
#include "local.h"
char *
_vasniprintf_r (struct _reent *ptr,
char *buf,
size_t *lenp,
const char *fmt,
va_list ap)
{
int ret;
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. */
ret = _svfiprintf_r (ptr, &f, fmt, ap);
if (ret < 0)
return NULL;
*lenp = ret;
*f._p = '\0';
return (char *) f._bf._base;
}
#ifndef _REENT_ONLY
char *
vasniprintf (char *buf,
size_t *lenp,
const char *fmt,
va_list ap)
{
return _vasniprintf_r (_REENT, buf, lenp, fmt, ap);
}
#endif /* ! _REENT_ONLY */