1 /*- 2 * Copyright (c) 2007 Sean C. Farley <scf@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer, 10 * without modification, immediately at the beginning of the file. 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 AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 #include <errno.h> 27 #include <libgen.h> 28 #include <stdbool.h> 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 39 extern char **environ; 40 41 42 static void 43 dump_environ(void) 44 { 45 char **environPtr; 46 47 for (environPtr = environ; *environPtr != NULL; *environPtr++) 48 printf("%s\n", *environPtr); 49 50 return; 51 } 52 53 54 static void 55 usage(const char *program) 56 { 57 fprintf(stderr, "Usage: %s [-CDGUchrt] [-gu name] [-p name=value] " 58 "[(-S|-s name) value overwrite]\n\n" 59 "Options:\n" 60 " -C\t\t\t\tClear environ variable with NULL pointer\n" 61 " -D\t\t\t\tDump environ\n" 62 " -G name\t\t\tgetenv(NULL)\n" 63 " -S value overwrite\t\tsetenv(NULL, value, overwrite)\n" 64 " -U\t\t\t\tunsetenv(NULL)\n" 65 " -c\t\t\t\tClear environ variable with calloc()'d memory\n" 66 " -g name\t\t\tgetenv(name)\n" 67 " -h\t\t\t\tHelp\n" 68 " -p name=value\t\t\tputenv(name=value)\n" 69 " -r\t\t\t\treplace environ with { \"FOO=bar\", NULL }\n" 70 " -s name value overwrite\tsetenv(name, value, overwrite)\n" 71 " -t\t\t\t\tOutput is suitable for testing (no newlines)\n" 72 " -u name\t\t\tunsetenv(name)\n", 73 basename(program)); 74 75 return; 76 } 77 78 79 int 80 main(int argc, char **argv) 81 { 82 char *staticEnv[] = { "FOO=bar", NULL }; 83 char arg; 84 const char *eol = "\n"; 85 const char *value; 86 87 if (argc == 1) { 88 usage(argv[0]); 89 exit(EXIT_FAILURE); 90 } 91 92 while ((arg = getopt(argc, argv, "CDGS:Ucg:hp:rs:tu:")) != -1) { 93 switch (arg) { 94 case 'C': 95 environ = NULL; 96 break; 97 98 case 'c': 99 environ = calloc(1, sizeof(*environ)); 100 break; 101 102 case 'D': 103 errno = 0; 104 dump_environ(); 105 break; 106 107 case 'G': 108 value = getenv(NULL); 109 printf("%s%s", value == NULL ? "" : value, eol); 110 break; 111 112 case 'g': 113 value = getenv(optarg); 114 printf("%s%s", value == NULL ? "" : value, eol); 115 break; 116 117 case 'p': 118 errno = 0; 119 printf("%d %d%s", putenv(optarg), errno, eol); 120 break; 121 122 case 'r': 123 environ = staticEnv; 124 break; 125 126 case 'S': 127 errno = 0; 128 printf("%d %d%s", setenv(NULL, optarg, 129 atoi(argv[optind])), errno, eol); 130 optind += 1; 131 break; 132 133 case 's': 134 errno = 0; 135 printf("%d %d%s", setenv(optarg, argv[optind], 136 atoi(argv[optind + 1])), errno, eol); 137 optind += 2; 138 break; 139 140 case 't': 141 eol = " "; 142 break; 143 144 case 'U': 145 printf("%d %d%s", unsetenv(NULL), errno, eol); 146 break; 147 148 case 'u': 149 printf("%d %d%s", unsetenv(optarg), errno, eol); 150 break; 151 152 case 'h': 153 default: 154 usage(argv[0]); 155 exit(EXIT_FAILURE); 156 } 157 } 158 159 // Output a closing newline in test mode. 160 if (eol[0] == ' ') 161 printf("\n"); 162 163 return (EXIT_SUCCESS); 164 } 165