1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright 2020 Stefan Eßer <se@freebsd.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/param.h> 32 #include <sys/sysctl.h> 33 #include <sys/limits.h> 34 #include <errno.h> 35 #include <stdlib.h> 36 #include <paths.h> 37 #include <libutil.h> 38 #include <unistd.h> 39 40 #ifndef _PATH_LOCALBASE 41 #define _PATH_LOCALBASE "/usr/local" 42 #endif 43 44 #ifndef LOCALBASE_CTL_LEN 45 #define LOCALBASE_CTL_LEN MAXPATHLEN 46 #endif 47 48 /* Any prefix guaranteed to not be the start of a valid path name */ 49 #define ILLEGAL_PREFIX "/dev/null/" 50 51 const char * 52 getlocalbase(void) 53 { 54 #if LOCALBASE_CTL_LEN > 0 55 int localbase_oid[2] = {CTL_USER, USER_LOCALBASE}; 56 static char localpath[LOCALBASE_CTL_LEN]; 57 size_t localpathlen = LOCALBASE_CTL_LEN; 58 #endif 59 char *tmppath; 60 static const char *localbase = NULL; 61 62 if (localbase != NULL) 63 return (localbase); 64 65 if (issetugid() == 0) { 66 tmppath = getenv("LOCALBASE"); 67 if (tmppath != NULL && tmppath[0] != '\0') { 68 localbase = tmppath; 69 return (localbase); 70 } 71 } 72 73 #if LOCALBASE_CTL_LEN > 0 74 if (sysctl(localbase_oid, 2, localpath, &localpathlen, NULL, 0) != 0) { 75 if (errno != ENOMEM) 76 localbase = _PATH_LOCALBASE; 77 else 78 localbase = ILLEGAL_PREFIX; 79 } else { 80 if (localpath[0] != '\0') 81 localbase = localpath; 82 else 83 localbase = _PATH_LOCALBASE; 84 } 85 #else 86 localbase = _PATH_LOCALBASE; 87 #endif 88 89 return (localbase); 90 } 91