1 /* $OpenBSD: asprintf.c,v 1.8 2002/02/19 19:39:36 millert Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 19 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 20 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 21 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 22 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 23 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 24 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 25 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 26 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 27 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #if defined(LIBC_SCCS) && !defined(lint) 31 static char rcsid[] = "$OpenBSD: asprintf.c,v 1.8 2002/02/19 19:39:36 millert Exp $"; 32 #endif /* LIBC_SCCS and not lint */ 33 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <errno.h> 37 #include <stdarg.h> 38 39 int 40 asprintf(char **str, char const *fmt, ...) 41 { 42 int ret; 43 va_list ap; 44 FILE f; 45 unsigned char *_base; 46 47 va_start(ap, fmt); 48 f._file = -1; 49 f._flags = __SWR | __SSTR | __SALC; 50 f._bf._base = f._p = (unsigned char *)malloc(128); 51 if (f._bf._base == NULL) 52 goto err; 53 f._bf._size = f._w = 127; /* Leave room for the NUL */ 54 ret = vfprintf(&f, fmt, ap); 55 if (ret == -1) 56 goto err; 57 *f._p = '\0'; 58 _base = realloc(f._bf._base, ret + 1); 59 if (_base == NULL) 60 goto err; 61 *str = (char *)_base; 62 va_end(ap); 63 return (ret); 64 65 err: 66 va_end(ap); 67 if (f._bf._base) { 68 free(f._bf._base); 69 f._bf._base = NULL; 70 } 71 *str = NULL; 72 errno = ENOMEM; 73 return (-1); 74 } 75