1 /* $NetBSD: whereis.c,v 1.17 2004/05/23 02:24:06 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1993 5 * The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1993\n\ 35 The Regents of the University of California. All rights reserved.\n"); 36 #endif /* not lint */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)whereis.c 8.3 (Berkeley) 5/4/95"; 41 #endif 42 __RCSID("$NetBSD: whereis.c,v 1.17 2004/05/23 02:24:06 christos Exp $"); 43 #endif /* not lint */ 44 45 #include <sys/param.h> 46 #include <sys/stat.h> 47 #include <sys/sysctl.h> 48 49 #include <err.h> 50 #include <errno.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <unistd.h> 55 56 static void usage(void) __attribute__((__noreturn__)); 57 58 int 59 main(int argc, char *argv[]) 60 { 61 struct stat sb; 62 size_t len; 63 int ch, mib[2]; 64 char *p, *std, path[MAXPATHLEN]; 65 const char *t; 66 int which = strcmp(getprogname(), "which") == 0; 67 int useenvpath = which, found = 0; 68 gid_t egid = getegid(); 69 uid_t euid = geteuid(); 70 71 /* To make access(2) do what we want */ 72 if (setgid(egid) == -1) 73 err(1, "Can't set gid to %lu", (unsigned long)egid); 74 if (setuid(euid) == -1) 75 err(1, "Can't set uid to %lu", (unsigned long)euid); 76 77 while ((ch = getopt(argc, argv, "ap")) != -1) 78 switch (ch) { 79 case 'a': 80 which = 0; 81 break; 82 case 'p': 83 useenvpath = 1; /* use environment for PATH */ 84 break; 85 86 case '?': 87 default: 88 usage(); 89 } 90 argc -= optind; 91 argv += optind; 92 93 if (argc == 0) 94 usage(); 95 96 if (useenvpath) { 97 if ((std = getenv("PATH")) == NULL) 98 errx(1, "PATH environment variable is not set"); 99 } else { 100 /* Retrieve the standard path. */ 101 mib[0] = CTL_USER; 102 mib[1] = USER_CS_PATH; 103 if (sysctl(mib, 2, NULL, &len, NULL, 0) == -1) 104 err(1, "sysctl: user.cs_path"); 105 if (len == 0) 106 errx(1, "sysctl: user.cs_path (zero length)"); 107 if ((std = malloc(len)) == NULL) 108 err(1, NULL); 109 if (sysctl(mib, 2, std, &len, NULL, 0) == -1) 110 err(1, "sysctl: user.cs_path"); 111 } 112 113 /* For each path, for each program... */ 114 for (; *argv; ++argv) 115 for (p = std; p; p && (*p++ = ':')) { 116 t = p; 117 if ((p = strchr(p, ':')) != NULL) { 118 *p = '\0'; 119 if (t == p) 120 t = "."; 121 } else 122 if (strlen(t) == 0) 123 t = "."; 124 (void)snprintf(path, sizeof(path), "%s/%s", t, *argv); 125 len = snprintf(path, sizeof(path), "%s/%s", t, *argv); 126 if (len >= sizeof(path)) 127 continue; 128 if (stat(path, &sb) == -1) 129 continue; 130 if (!S_ISREG(sb.st_mode)) 131 continue; 132 if (access(path, X_OK) == -1) 133 continue; 134 (void)printf("%s\n", path); 135 found++; 136 if (which) 137 break; 138 } 139 140 return ((found == 0) ? 3 : ((found >= argc) ? 0 : 2)); 141 } 142 143 static void 144 usage(void) 145 { 146 147 (void)fprintf(stderr, "Usage: %s [-ap] program [...]\n", getprogname()); 148 exit(1); 149 } 150