1 /* $OpenBSD: environ.c,v 1.15 2016/07/15 09:52:34 nicm Exp $ */ 2 3 /* 4 * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER 15 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 16 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/types.h> 20 21 #include <stdlib.h> 22 #include <string.h> 23 24 #include "tmux.h" 25 26 /* 27 * Environment - manipulate a set of environment variables. 28 */ 29 30 RB_HEAD(environ, environ_entry); 31 int environ_cmp(struct environ_entry *, struct environ_entry *); 32 RB_PROTOTYPE(environ, environ_entry, entry, environ_cmp); 33 RB_GENERATE(environ, environ_entry, entry, environ_cmp); 34 35 int 36 environ_cmp(struct environ_entry *envent1, struct environ_entry *envent2) 37 { 38 return (strcmp(envent1->name, envent2->name)); 39 } 40 41 /* Initialise the environment. */ 42 struct environ * 43 environ_create(void) 44 { 45 struct environ *env; 46 47 env = xcalloc(1, sizeof *env); 48 RB_INIT(env); 49 50 return (env); 51 } 52 53 /* Free an environment. */ 54 void 55 environ_free(struct environ *env) 56 { 57 struct environ_entry *envent, *envent1; 58 59 RB_FOREACH_SAFE(envent, environ, env, envent1) { 60 RB_REMOVE(environ, env, envent); 61 free(envent->name); 62 free(envent->value); 63 free(envent); 64 } 65 free(env); 66 } 67 68 struct environ_entry * 69 environ_first(struct environ *env) 70 { 71 return (RB_MIN(environ, env)); 72 } 73 74 struct environ_entry * 75 environ_next(struct environ_entry *envent) 76 { 77 return (RB_NEXT(environ, env, envent)); 78 } 79 80 /* Copy one environment into another. */ 81 void 82 environ_copy(struct environ *srcenv, struct environ *dstenv) 83 { 84 struct environ_entry *envent; 85 86 RB_FOREACH(envent, environ, srcenv) { 87 if (envent->value == NULL) 88 environ_clear(dstenv, envent->name); 89 else 90 environ_set(dstenv, envent->name, "%s", envent->value); 91 } 92 } 93 94 /* Find an environment variable. */ 95 struct environ_entry * 96 environ_find(struct environ *env, const char *name) 97 { 98 struct environ_entry envent; 99 100 envent.name = (char *) name; 101 return (RB_FIND(environ, env, &envent)); 102 } 103 104 /* Set an environment variable. */ 105 void 106 environ_set(struct environ *env, const char *name, const char *fmt, ...) 107 { 108 struct environ_entry *envent; 109 va_list ap; 110 111 va_start(ap, fmt); 112 if ((envent = environ_find(env, name)) != NULL) { 113 free(envent->value); 114 xvasprintf(&envent->value, fmt, ap); 115 } else { 116 envent = xmalloc(sizeof *envent); 117 envent->name = xstrdup(name); 118 xvasprintf(&envent->value, fmt, ap); 119 RB_INSERT(environ, env, envent); 120 } 121 va_end(ap); 122 } 123 124 /* Clear an environment variable. */ 125 void 126 environ_clear(struct environ *env, const char *name) 127 { 128 struct environ_entry *envent; 129 130 if ((envent = environ_find(env, name)) != NULL) { 131 free(envent->value); 132 envent->value = NULL; 133 } else { 134 envent = xmalloc(sizeof *envent); 135 envent->name = xstrdup(name); 136 envent->value = NULL; 137 RB_INSERT(environ, env, envent); 138 } 139 } 140 141 /* Set an environment variable from a NAME=VALUE string. */ 142 void 143 environ_put(struct environ *env, const char *var) 144 { 145 char *name, *value; 146 147 value = strchr(var, '='); 148 if (value == NULL) 149 return; 150 value++; 151 152 name = xstrdup(var); 153 name[strcspn(name, "=")] = '\0'; 154 155 environ_set(env, name, "%s", value); 156 free(name); 157 } 158 159 /* Unset an environment variable. */ 160 void 161 environ_unset(struct environ *env, const char *name) 162 { 163 struct environ_entry *envent; 164 165 if ((envent = environ_find(env, name)) == NULL) 166 return; 167 RB_REMOVE(environ, env, envent); 168 free(envent->name); 169 free(envent->value); 170 free(envent); 171 } 172 173 /* 174 * Copy a space-separated list of variables from a destination into a source 175 * environment. 176 */ 177 void 178 environ_update(const char *vars, struct environ *srcenv, 179 struct environ *dstenv) 180 { 181 struct environ_entry *envent; 182 char *copyvars, *var, *next; 183 184 copyvars = next = xstrdup(vars); 185 while ((var = strsep(&next, " ")) != NULL) { 186 if ((envent = environ_find(srcenv, var)) == NULL) 187 environ_clear(dstenv, var); 188 else 189 environ_set(dstenv, envent->name, "%s", envent->value); 190 } 191 free(copyvars); 192 } 193 194 /* Push environment into the real environment - use after fork(). */ 195 void 196 environ_push(struct environ *env) 197 { 198 struct environ_entry *envent; 199 200 environ = xcalloc(1, sizeof *environ); 201 RB_FOREACH(envent, environ, env) { 202 if (envent->value != NULL && *envent->name != '\0') 203 setenv(envent->name, envent->value, 1); 204 } 205 } 206 207 /* Log the environment. */ 208 void 209 environ_log(struct environ *env, const char *prefix) 210 { 211 struct environ_entry *envent; 212 213 RB_FOREACH(envent, environ, env) { 214 if (envent->value != NULL && *envent->name != '\0') { 215 log_debug("%s%s=%s", prefix, envent->name, 216 envent->value); 217 } 218 } 219 } 220