1 /* 2 * Copyright (c) 2000 Peter Wemm <peter@freebsd.org> 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 * $FreeBSD: src/usr.bin/kenv/kenv.c,v 1.1.2.2 2001/12/19 04:52:15 dd Exp $ 26 */ 27 #include <sys/types.h> 28 #include <sys/sysctl.h> 29 #include <stdlib.h> 30 #include <stdio.h> 31 #include <string.h> 32 #include <errno.h> 33 #include <err.h> 34 #include <unistd.h> 35 36 static char sbuf[1024]; 37 38 static void 39 usage(void) 40 { 41 (void)fprintf(stderr, "usage: kenv [-h] [variable]\n"); 42 exit(1); 43 } 44 45 int 46 main(int argc, char **argv) 47 { 48 int name2oid_oid[2]; 49 int real_oid[CTL_MAXNAME+4]; 50 size_t oidlen; 51 int ch, error, hflag, i, slen; 52 char *env, *eq, *name, *var, *val; 53 54 hflag = 0; 55 env = NULL; 56 while ((ch = getopt(argc, argv, "h")) != -1) { 57 switch (ch) { 58 case 'h': 59 hflag++; 60 break; 61 default: 62 usage(); 63 } 64 } 65 argc -= optind; 66 argv += optind; 67 if (argc > 0) { 68 env = argv[0]; 69 argv++; 70 argc--; 71 } 72 if (argc > 0) 73 usage(); 74 name2oid_oid[0] = 0; /* This is magic & undocumented! */ 75 name2oid_oid[1] = 3; 76 oidlen = sizeof(real_oid); 77 name = "kern.environment"; 78 error = sysctl(name2oid_oid, 2, real_oid, &oidlen, name, strlen(name)); 79 if (error < 0) 80 err(1, "cannot find kern.environment base sysctl OID"); 81 oidlen /= sizeof (int); 82 if (oidlen >= CTL_MAXNAME) 83 errx(1, "kern.environment OID is too large!"); 84 real_oid[oidlen] = 0; 85 for (i = 0; ; i++) { 86 real_oid[oidlen + 1] = i; 87 slen = sizeof(sbuf) - 1; 88 error = sysctl(real_oid, oidlen + 2, sbuf, &slen, NULL, 0); 89 if (error < 0) { 90 if (errno != ENOENT) 91 err(1, "sysctl kern.environment.%d\n", i); 92 break; 93 } 94 sbuf[sizeof(sbuf) - 1] = '\0'; 95 eq = strchr(sbuf, '='); 96 if (eq == NULL) 97 err(1, "malformed environment string: %s\n", sbuf); 98 var = sbuf; 99 *eq = '\0'; 100 val = eq + 1; 101 if (env) { 102 if (strcmp(var, env) != 0) 103 continue; 104 printf("%s\n", val); 105 break; 106 } 107 if (hflag) { 108 if (strncmp(var, "hint.", 5) != 0) 109 continue; 110 /* FALLTHROUGH */ 111 } 112 printf("%s=\"", var); 113 while (*val) { 114 switch (*val) { 115 case '"': 116 putchar('\\'); 117 putchar('"'); 118 break; 119 case '\\': 120 putchar('\\'); 121 putchar('\\'); 122 break; 123 default: 124 putchar(*val); 125 break; 126 } 127 val++; 128 } 129 printf("\"\n"); 130 } 131 exit(0); 132 } 133