1 /*- 2 * Copyright (c) 1998 Michael Smith 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 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $Id: kern_environment.c,v 1.5 1999/01/27 21:24:50 dillon Exp $ 27 */ 28 29 /* 30 * The unified bootloader passes us a pointer to a preserved copy of 31 * bootstrap/kernel environment variables. 32 * We make these available using sysctl for both in-kernel and 33 * out-of-kernel consumers. 34 * 35 * Note that the current sysctl infrastructure doesn't allow 36 * dynamic insertion or traversal through handled spaces. Grr. 37 */ 38 39 #include <sys/param.h> 40 #include <sys/kernel.h> 41 #include <sys/systm.h> 42 #include <sys/sysctl.h> 43 #include <sys/libkern.h> 44 #include <machine/bootinfo.h> 45 46 char *kern_envp; 47 48 static char *kernenv_next(char *cp); 49 50 char * 51 getenv(char *name) 52 { 53 char *cp, *ep; 54 int len; 55 56 for (cp = kern_envp; cp != NULL; cp = kernenv_next(cp)) { 57 for (ep = cp; (*ep != '=') && (*ep != 0); ep++) 58 ; 59 len = ep - cp; 60 if (*ep == '=') 61 ep++; 62 if (!strncmp(name, cp, len)) 63 return(ep); 64 } 65 return(NULL); 66 } 67 68 /* 69 * Return an integer value from an environment variable. 70 */ 71 int 72 getenv_int(char *name, int *data) 73 { 74 const char *value, *vtp; 75 quad_t iv; 76 77 if ((value = getenv(name)) == NULL) 78 return(0); 79 80 iv = strtoq(value, &vtp, 0); 81 if ((vtp == value) || (*vtp != 0)) 82 return(0); 83 84 *data = (int)iv; 85 return(1); 86 } 87 88 static int 89 sysctl_kernenv SYSCTL_HANDLER_ARGS 90 { 91 int *name = (int *)arg1; 92 u_int namelen = arg2; 93 char *cp; 94 int i, error; 95 96 if (kern_envp == NULL) 97 return(ENOENT); 98 99 name++; 100 namelen--; 101 102 if (namelen != 1) 103 return(EINVAL); 104 105 cp = kern_envp; 106 for (i = 0; i < name[0]; i++) { 107 cp = kernenv_next(cp); 108 if (cp == NULL) 109 break; 110 } 111 112 if (cp == NULL) 113 return(ENOENT); 114 115 error = SYSCTL_OUT(req, cp, strlen(cp) + 1); 116 return (error); 117 } 118 119 SYSCTL_NODE(_kern, OID_AUTO, environment, CTLFLAG_RD, sysctl_kernenv, "kernel environment space"); 120 121 /* 122 * Find the next entry after the one which (cp) falls within, return a 123 * pointer to its start or NULL if there are no more. 124 */ 125 static char * 126 kernenv_next(char *cp) 127 { 128 if (cp != NULL) { 129 while (*cp != 0) 130 cp++; 131 cp++; 132 if (*cp == 0) 133 cp = NULL; 134 } 135 return(cp); 136 } 137 138