environment.c revision 1.1.2.2
1 1.1.2.2 yamt /* $NetBSD: environment.c,v 1.1.2.2 2006/04/11 11:53:40 yamt Exp $ */ 2 1.1.2.2 yamt 3 1.1.2.2 yamt 4 1.1.2.2 yamt /* 5 1.1.2.2 yamt * Copyright (c) 1998 Michael Smith. 6 1.1.2.2 yamt * All rights reserved. 7 1.1.2.2 yamt * 8 1.1.2.2 yamt * Redistribution and use in source and binary forms, with or without 9 1.1.2.2 yamt * modification, are permitted provided that the following conditions 10 1.1.2.2 yamt * are met: 11 1.1.2.2 yamt * 1. Redistributions of source code must retain the above copyright 12 1.1.2.2 yamt * notice, this list of conditions and the following disclaimer. 13 1.1.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 14 1.1.2.2 yamt * notice, this list of conditions and the following disclaimer in the 15 1.1.2.2 yamt * documentation and/or other materials provided with the distribution. 16 1.1.2.2 yamt * 17 1.1.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 1.1.2.2 yamt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 1.1.2.2 yamt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 1.1.2.2 yamt * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 1.1.2.2 yamt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 1.1.2.2 yamt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 1.1.2.2 yamt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 1.1.2.2 yamt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 1.1.2.2 yamt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 1.1.2.2 yamt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 1.1.2.2 yamt * SUCH DAMAGE. 28 1.1.2.2 yamt */ 29 1.1.2.2 yamt 30 1.1.2.2 yamt #include <sys/cdefs.h> 31 1.1.2.2 yamt 32 1.1.2.2 yamt /* 33 1.1.2.2 yamt * Manage an environment-like space in which string variables may be stored. 34 1.1.2.2 yamt * Provide support for some method-like operations for setting/retrieving 35 1.1.2.2 yamt * variables in order to allow some type strength. 36 1.1.2.2 yamt */ 37 1.1.2.2 yamt 38 1.1.2.2 yamt #include <lib/libsa/stand.h> 39 1.1.2.2 yamt #include <lib/libkern/libkern.h> 40 1.1.2.2 yamt 41 1.1.2.2 yamt #include <bootstrap.h> 42 1.1.2.2 yamt 43 1.1.2.2 yamt static void env_discard(struct env_var *ev); 44 1.1.2.2 yamt 45 1.1.2.2 yamt struct env_var *environ = NULL; 46 1.1.2.2 yamt 47 1.1.2.2 yamt /* 48 1.1.2.2 yamt * Look up (name) and return it's env_var structure. 49 1.1.2.2 yamt */ 50 1.1.2.2 yamt struct env_var * 51 1.1.2.2 yamt env_getenv(const char *name) 52 1.1.2.2 yamt { 53 1.1.2.2 yamt struct env_var *ev; 54 1.1.2.2 yamt 55 1.1.2.2 yamt for (ev = environ; ev != NULL; ev = ev->ev_next) 56 1.1.2.2 yamt if (!strcmp(ev->ev_name, name)) 57 1.1.2.2 yamt break; 58 1.1.2.2 yamt return(ev); 59 1.1.2.2 yamt } 60 1.1.2.2 yamt 61 1.1.2.2 yamt /* 62 1.1.2.2 yamt * Some notes: 63 1.1.2.2 yamt * 64 1.1.2.2 yamt * If the EV_VOLATILE flag is set, a copy of the variable is made. 65 1.1.2.2 yamt * If EV_DYNAMIC is set, the the variable has been allocated with 66 1.1.2.2 yamt * malloc and ownership transferred to the environment. 67 1.1.2.2 yamt * If (value) is NULL, the variable is set but has no value. 68 1.1.2.2 yamt */ 69 1.1.2.2 yamt int 70 1.1.2.2 yamt env_setenv(const char *name, int flags, const void *value, 71 1.1.2.2 yamt ev_sethook_t sethook, ev_unsethook_t unsethook) 72 1.1.2.2 yamt { 73 1.1.2.2 yamt struct env_var *ev, *curr, *last; 74 1.1.2.2 yamt 75 1.1.2.2 yamt if ((ev = env_getenv(name)) != NULL) { 76 1.1.2.2 yamt /* 77 1.1.2.2 yamt * If there's a set hook, let it do the work (unless we are working 78 1.1.2.2 yamt * for one already. 79 1.1.2.2 yamt */ 80 1.1.2.2 yamt if ((ev->ev_sethook != NULL) && !(flags & EV_NOHOOK)) 81 1.1.2.2 yamt return(ev->ev_sethook(ev, flags, value)); 82 1.1.2.2 yamt } else { 83 1.1.2.2 yamt 84 1.1.2.2 yamt /* 85 1.1.2.2 yamt * New variable; create and sort into list 86 1.1.2.2 yamt */ 87 1.1.2.2 yamt ev = alloc(sizeof(struct env_var)); 88 1.1.2.2 yamt ev->ev_name = strdup(name); 89 1.1.2.2 yamt ev->ev_value = NULL; 90 1.1.2.2 yamt /* hooks can only be set when the variable is instantiated */ 91 1.1.2.2 yamt ev->ev_sethook = sethook; 92 1.1.2.2 yamt ev->ev_unsethook = unsethook; 93 1.1.2.2 yamt 94 1.1.2.2 yamt /* Sort into list */ 95 1.1.2.2 yamt ev->ev_prev = NULL; 96 1.1.2.2 yamt ev->ev_next = NULL; 97 1.1.2.2 yamt /* Search for the record to insert before */ 98 1.1.2.2 yamt for (last = NULL, curr = environ; 99 1.1.2.2 yamt curr != NULL; 100 1.1.2.2 yamt last = curr, curr = curr->ev_next) { 101 1.1.2.2 yamt 102 1.1.2.2 yamt if (strcmp(ev->ev_name, curr->ev_name) < 0) { 103 1.1.2.2 yamt if (curr->ev_prev) { 104 1.1.2.2 yamt curr->ev_prev->ev_next = ev; 105 1.1.2.2 yamt } else { 106 1.1.2.2 yamt environ = ev; 107 1.1.2.2 yamt } 108 1.1.2.2 yamt ev->ev_next = curr; 109 1.1.2.2 yamt ev->ev_prev = curr->ev_prev; 110 1.1.2.2 yamt curr->ev_prev = ev; 111 1.1.2.2 yamt break; 112 1.1.2.2 yamt } 113 1.1.2.2 yamt } 114 1.1.2.2 yamt if (curr == NULL) { 115 1.1.2.2 yamt if (last == NULL) { 116 1.1.2.2 yamt environ = ev; 117 1.1.2.2 yamt } else { 118 1.1.2.2 yamt last->ev_next = ev; 119 1.1.2.2 yamt ev->ev_prev = last; 120 1.1.2.2 yamt } 121 1.1.2.2 yamt } 122 1.1.2.2 yamt } 123 1.1.2.2 yamt 124 1.1.2.2 yamt /* If there is data in the variable, discard it */ 125 1.1.2.2 yamt if (ev->ev_value != NULL) 126 1.1.2.2 yamt free(ev->ev_value); 127 1.1.2.2 yamt 128 1.1.2.2 yamt /* If we have a new value, use it */ 129 1.1.2.2 yamt if (flags & EV_VOLATILE) { 130 1.1.2.2 yamt ev->ev_value = strdup(value); 131 1.1.2.2 yamt } else { 132 1.1.2.2 yamt ev->ev_value = (void *) value; 133 1.1.2.2 yamt } 134 1.1.2.2 yamt 135 1.1.2.2 yamt /* Keep the flag components that are relevant */ 136 1.1.2.2 yamt ev->ev_flags = flags & (EV_DYNAMIC); 137 1.1.2.2 yamt 138 1.1.2.2 yamt return(0); 139 1.1.2.2 yamt } 140 1.1.2.2 yamt 141 1.1.2.2 yamt char * 142 1.1.2.2 yamt getenv(const char *name) 143 1.1.2.2 yamt { 144 1.1.2.2 yamt struct env_var *ev; 145 1.1.2.2 yamt 146 1.1.2.2 yamt /* Set but no value gives empty string */ 147 1.1.2.2 yamt if ((ev = env_getenv(name)) != NULL) { 148 1.1.2.2 yamt if (ev->ev_value != NULL) 149 1.1.2.2 yamt return(ev->ev_value); 150 1.1.2.2 yamt return(""); 151 1.1.2.2 yamt } 152 1.1.2.2 yamt return(NULL); 153 1.1.2.2 yamt } 154 1.1.2.2 yamt 155 1.1.2.2 yamt int 156 1.1.2.2 yamt setenv(const char *name, const char *value, int overwrite) 157 1.1.2.2 yamt { 158 1.1.2.2 yamt /* No guarantees about state, always assume volatile */ 159 1.1.2.2 yamt if (overwrite || (env_getenv(name) == NULL)) 160 1.1.2.2 yamt return(env_setenv(name, EV_VOLATILE, value, NULL, NULL)); 161 1.1.2.2 yamt return(0); 162 1.1.2.2 yamt } 163 1.1.2.2 yamt 164 1.1.2.2 yamt int 165 1.1.2.2 yamt putenv(const char *string) 166 1.1.2.2 yamt { 167 1.1.2.2 yamt char *value, *copy; 168 1.1.2.2 yamt int result; 169 1.1.2.2 yamt 170 1.1.2.2 yamt copy = strdup(string); 171 1.1.2.2 yamt if ((value = strchr(copy, '=')) != NULL) 172 1.1.2.2 yamt *(value++) = 0; 173 1.1.2.2 yamt result = setenv(copy, value, 1); 174 1.1.2.2 yamt free(copy); 175 1.1.2.2 yamt return(result); 176 1.1.2.2 yamt } 177 1.1.2.2 yamt 178 1.1.2.2 yamt int 179 1.1.2.2 yamt unsetenv(const char *name) 180 1.1.2.2 yamt { 181 1.1.2.2 yamt struct env_var *ev; 182 1.1.2.2 yamt int err; 183 1.1.2.2 yamt 184 1.1.2.2 yamt err = 0; 185 1.1.2.2 yamt if ((ev = env_getenv(name)) == NULL) { 186 1.1.2.2 yamt err = ENOENT; 187 1.1.2.2 yamt } else { 188 1.1.2.2 yamt if (ev->ev_unsethook != NULL) 189 1.1.2.2 yamt err = ev->ev_unsethook(ev); 190 1.1.2.2 yamt if (err == 0) { 191 1.1.2.2 yamt env_discard(ev); 192 1.1.2.2 yamt } 193 1.1.2.2 yamt } 194 1.1.2.2 yamt return(err); 195 1.1.2.2 yamt } 196 1.1.2.2 yamt 197 1.1.2.2 yamt static void 198 1.1.2.2 yamt env_discard(struct env_var *ev) 199 1.1.2.2 yamt { 200 1.1.2.2 yamt if (ev->ev_prev) 201 1.1.2.2 yamt ev->ev_prev->ev_next = ev->ev_next; 202 1.1.2.2 yamt if (ev->ev_next) 203 1.1.2.2 yamt ev->ev_next->ev_prev = ev->ev_prev; 204 1.1.2.2 yamt if (environ == ev) 205 1.1.2.2 yamt environ = ev->ev_next; 206 1.1.2.2 yamt free(ev->ev_name); 207 1.1.2.2 yamt if (ev->ev_flags & EV_DYNAMIC) 208 1.1.2.2 yamt free(ev->ev_value); 209 1.1.2.2 yamt free(ev); 210 1.1.2.2 yamt } 211 1.1.2.2 yamt 212 1.1.2.2 yamt int 213 1.1.2.2 yamt env_noset(struct env_var *ev, int flags, const void *value) 214 1.1.2.2 yamt { 215 1.1.2.2 yamt return(EPERM); 216 1.1.2.2 yamt } 217 1.1.2.2 yamt 218 1.1.2.2 yamt int 219 1.1.2.2 yamt env_nounset(struct env_var *ev) 220 1.1.2.2 yamt { 221 1.1.2.2 yamt return(EPERM); 222 1.1.2.2 yamt } 223
Indexes created Thu Oct 23 22:10:10 GMT 2025