9 /* $Id: compat_vasprintf.c,v 1.3 2015/10/06 18:32:19 schwarze Exp $ */
11 * Copyright (c) 2015 Ingo Schwarze <schwarze@openbsd.org>
13 * Permission to use, copy, modify, and distribute this software for any
14 * purpose with or without fee is hereby granted, provided that the above
15 * copyright notice and this permission notice appear in all copies.
17 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
18 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
20 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
21 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
22 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
23 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
25 * This fallback implementation is not efficient:
26 * It does the formatting twice.
27 * Short of fiddling with the unknown internals of the system's
28 * printf(3) or completely reimplementing printf(3), i can't think
29 * of another portable solution.
37 vasprintf(char **ret, const char *format, va_list ap)
44 sz = vsnprintf(buf, sizeof(buf), format, ap2);
47 if (sz != -1 && (*ret = malloc(sz + 1)) != NULL) {
48 if (vsnprintf(*ret, sz + 1, format, ap) == sz)