1 /* $NetBSD: nan.c,v 1.1 2006/03/15 22:07:09 kleink Exp $ */ 2 3 /*- 4 * Copyright (c) 2006 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Klaus Klein. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBM_SCCS) && !defined(lint) && !defined(NAN_FUNCTION) 41 __RCSID("$NetBSD: nan.c,v 1.1 2006/03/15 22:07:09 kleink Exp $"); 42 #endif /* LIBM_SCCS and not lint */ 43 44 #include <assert.h> 45 #include <math.h> 46 #include <stddef.h> 47 #include <stdlib.h> 48 #include <string.h> 49 50 51 #ifndef NAN_FUNCTION 52 #define NAN_FUNCTION nan 53 #define NAN_TYPE double 54 #define NAN_STRTOD strtod 55 #endif 56 57 NAN_TYPE 58 NAN_FUNCTION(const char *tagp) 59 { 60 const char *nstr; 61 char *buf; 62 NAN_TYPE res; 63 64 _DIAGASSERT(tagp != NULL); 65 66 nstr = "NAN()"; 67 buf = NULL; 68 69 if (tagp[0] != '\0') { 70 size_t l; 71 72 l = strlen(tagp); 73 buf = malloc(5 + l + 1); 74 75 if (buf != NULL) { 76 /* Avoiding stdio in libm. */ 77 memcpy(buf, "NAN(", 4); 78 memcpy(buf + 4, tagp, l); 79 memcpy(buf + 4 + l, ")", 2); 80 nstr = buf; 81 } else { 82 /* Best effort: Fall back to "NAN()". */ 83 } 84 } 85 86 res = NAN_STRTOD(nstr, NULL); 87 88 if (buf != NULL) 89 free(buf); 90 91 return res; 92 } 93