1 /* $DragonFly: src/lib/libutil/trimdomain.c,v 1.2 2005/03/04 04:31:11 cpressey Exp $ */ 2 /* 3 * Copyright (c) 2001 Brian Somers <brian@Awfulhak.org> 4 * Based on original work by Atsushi Murai <amurai@FreeBSD.org> 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD: /repoman/r/ncvs/src/lib/libutil/trimdomain.c,v 1.5 2003/10/18 10:04:16 markm Exp $ 29 */ 30 31 #include <sys/cdefs.h> 32 #include <sys/param.h> 33 34 #include <string.h> 35 #include <unistd.h> 36 37 #include "libutil.h" 38 39 static int isDISP(const char *); 40 41 /*- 42 * Trim the current domain name from fullhost, but only if the result 43 * is less than or equal to hostsize in length. 44 * 45 * This function understands $DISPLAY type fullhosts. 46 * 47 * For example: 48 * 49 * trimdomain("abcde.my.domain", 5) -> "abcde" 50 * trimdomain("abcde.my.domain", 4) -> "abcde.my.domain" 51 * trimdomain("abcde.my.domain:0.0", 9) -> "abcde:0.0" 52 * trimdomain("abcde.my.domain:0.0", 8) -> "abcde.my.domain:0.0" 53 */ 54 void 55 trimdomain(char *fullhost, int hostsize) 56 { 57 static size_t dlen; 58 static int first = 1; 59 static char domain[MAXHOSTNAMELEN]; 60 char *end, *s; 61 size_t len; 62 63 if (first) { 64 /* XXX: Should we assume that our domain is this persistent ? */ 65 first = 0; 66 if (gethostname(domain, sizeof(domain) - 1) == 0 && 67 (s = strchr(domain, '.')) != NULL) 68 memmove(domain, s + 1, strlen(s + 1) + 1); 69 else 70 domain[0] = '\0'; 71 dlen = strlen(domain); 72 } 73 74 if (domain[0] == '\0') 75 return; 76 77 s = fullhost; 78 end = s + hostsize + 1; 79 for (; (s = memchr(s, '.', (size_t)(end - s))) != NULL; s++) { 80 if (strncasecmp(s + 1, domain, dlen) == 0) { 81 if (s[dlen + 1] == '\0') { 82 /* Found -- lose the domain. */ 83 *s = '\0'; 84 break; 85 } else if (s[dlen + 1] == ':' && 86 isDISP(s + dlen + 2) && 87 (len = strlen(s + dlen + 1)) < (size_t)(end - s)) { 88 /* Found -- shuffle the DISPLAY back. */ 89 memmove(s, s + dlen + 1, len + 1); 90 break; 91 } 92 } 93 } 94 } 95 96 /* 97 * Is the given string NN or NN.NN where ``NN'' is an all-numeric string ? 98 */ 99 static int 100 isDISP(const char *disp) 101 { 102 size_t w; 103 int res; 104 105 w = strspn(disp, "0123456789"); 106 res = 0; 107 if (w > 0) { 108 if (disp[w] == '\0') 109 res = 1; /* NN */ 110 else if (disp[w] == '.') { 111 disp += w + 1; 112 w = strspn(disp, "0123456789"); 113 if (w > 0 && disp[w] == '\0') 114 res = 1; /* NN.NN */ 115 } 116 } 117 return (res); 118 } 119