1 /* Formatted output to strings.
2 Copyright (C) 1999, 2002, 2006-2007 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify it
5 under the terms of the GNU Library General Public License as published
6 by the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Library General Public License for more details.
14 You should have received a copy of the GNU Library General Public
15 License along with this program; if not, write to the Free Software
16 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
19 /* Some systems, like OSF/1 4.0 and Woe32, don't have EOVERFLOW. */
21 # define EOVERFLOW E2BIG
25 # define SIZE_MAX ((size_t) -1)
29 VSPRINTF (DCHAR_T *buf, const FCHAR_T *format, va_list args)
31 /* Pass an infinite length. But note that *vasnprintf may fail if the buffer
32 argument is larger than INT_MAX (if that fits into a 'size_t' at all).
33 Also note that glibc's iconv fails with E2BIG when we pass a length that
34 is so large that buf + length wraps around, i.e.
35 (uintptr_t) (buf + length) < (uintptr_t) buf. */
39 /* Set length = min (SIZE_MAX, INT_MAX, - (uintptr_t) buf - 1). */
40 length = (SIZE_MAX < INT_MAX ? SIZE_MAX : INT_MAX);
41 if (length > (~ (uintptr_t) buf) / sizeof (DCHAR_T))
42 length = (~ (uintptr_t) buf) / sizeof (DCHAR_T);
44 result = VASNPRINTF (buf, &length, format, args);
48 /* The infinite buffer size guarantees that the result is not malloc()ed. */
51 /* length is near SIZE_MAX. */
63 /* Return the number of resulting units, excluding the trailing NUL. */