1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2000 Dan Papasian. All rights reserved. 5 * Copyright 2023 OmniOS Community Edition (OmniOSce) Association. 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 BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include <sys/fcntl.h> 31 #include <sys/param.h> 32 #include <sys/stat.h> 33 #include <err.h> 34 #include <limits.h> 35 #include <stdbool.h> 36 #include <stdio.h> 37 #include <stdlib.h> 38 #include <string.h> 39 #include <unistd.h> 40 41 #define EXIT_USAGE 2 42 43 static void usage(void) __NORETURN; 44 static bool print_matches(char *, const char *const); 45 46 static bool silent = false; 47 static bool allpaths = false; 48 49 int 50 main(int argc, char **argv) 51 { 52 char *p, *path; 53 size_t pathlen; 54 int opt, status; 55 56 status = EXIT_SUCCESS; 57 58 while ((opt = getopt(argc, argv, "as")) != -1) { 59 switch (opt) { 60 case 'a': 61 allpaths = true; 62 break; 63 case 's': 64 silent = true; 65 break; 66 default: 67 usage(); 68 break; 69 } 70 } 71 72 argv += optind; 73 argc -= optind; 74 75 if (argc == 0) 76 exit(EXIT_SUCCESS); 77 78 if ((p = getenv("PATH")) == NULL) 79 errx(EXIT_FAILURE, "Could not find PATH in environment"); 80 81 pathlen = strlen(p); 82 path = strdup(p); 83 84 if (path == NULL) 85 err(EXIT_FAILURE, "Failed to duplicate PATH"); 86 87 while (argc > 0) { 88 memcpy(path, p, pathlen + 1); 89 90 if (strlen(*argv) >= FILENAME_MAX) { 91 status = EXIT_FAILURE; 92 93 warnx("operand too long '%s'", *argv); 94 } else if (!print_matches(path, *argv)) { 95 status = EXIT_FAILURE; 96 97 if (!silent) { 98 (void) printf("no %s in", *argv); 99 100 if (pathlen > 0) { 101 char *q = path; 102 const char *d; 103 104 memcpy(q, p, pathlen + 1); 105 106 while ((d = strsep(&q, ":")) != NULL) { 107 (void) printf(" %s", 108 *d == '\0' ? "." : d); 109 } 110 } 111 112 (void) printf("\n"); 113 } 114 } 115 116 argv++; 117 argc--; 118 } 119 120 free(path); 121 exit(status); 122 } 123 124 static void 125 usage(void) 126 { 127 (void) fprintf(stderr, "usage: which [-as] program ...\n"); 128 exit(EXIT_USAGE); 129 } 130 131 static bool 132 is_there(const char *const candidate) 133 { 134 struct stat fin; 135 136 if (faccessat(AT_FDCWD, candidate, X_OK, AT_EACCESS) == 0 && 137 stat(candidate, &fin) == 0 && 138 S_ISREG(fin.st_mode)) { 139 if (!silent) 140 printf("%s\n", candidate); 141 142 return (true); 143 } 144 145 return (false); 146 } 147 148 static bool 149 print_matches(char *path, const char *const filename) 150 { 151 char candidate[PATH_MAX]; 152 const char *d; 153 bool found = false; 154 155 if (strchr(filename, '/') != NULL) 156 return (is_there(filename)); 157 158 while ((d = strsep(&path, ":")) != NULL) { 159 if (*d == '\0') 160 d = "."; 161 if (snprintf(candidate, sizeof (candidate), "%s/%s", d, 162 filename) >= (int)sizeof (candidate)) 163 continue; 164 if (is_there(candidate)) { 165 found = true; 166 if (!allpaths) 167 break; 168 } 169 } 170 171 return (found); 172 } 173