1 /* $OpenBSD: environ.c,v 1.5 2012/07/10 11:53:01 nicm Exp $ */ 2 3 /* 4 * Copyright (c) 2009 Nicholas Marriott <nicm@users.sourceforge.net> 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_GENERATE(environ, environ_entry, entry, environ_cmp); 31 32 int 33 environ_cmp(struct environ_entry *envent1, struct environ_entry *envent2) 34 { 35 return (strcmp(envent1->name, envent2->name)); 36 } 37 38 /* Initialise the environment. */ 39 void 40 environ_init(struct environ *env) 41 { 42 RB_INIT(env); 43 } 44 45 /* Free an environment. */ 46 void 47 environ_free(struct environ *env) 48 { 49 struct environ_entry *envent; 50 51 while (!RB_EMPTY(env)) { 52 envent = RB_ROOT(env); 53 RB_REMOVE(environ, env, envent); 54 free(envent->name); 55 free(envent->value); 56 free(envent); 57 } 58 } 59 60 /* Copy one environment into another. */ 61 void 62 environ_copy(struct environ *srcenv, struct environ *dstenv) 63 { 64 struct environ_entry *envent; 65 66 RB_FOREACH(envent, environ, srcenv) 67 environ_set(dstenv, envent->name, envent->value); 68 } 69 70 /* Find an environment variable. */ 71 struct environ_entry * 72 environ_find(struct environ *env, const char *name) 73 { 74 struct environ_entry envent; 75 76 envent.name = (char *) name; 77 return (RB_FIND(environ, env, &envent)); 78 } 79 80 /* Set an environment variable. */ 81 void 82 environ_set(struct environ *env, const char *name, const char *value) 83 { 84 struct environ_entry *envent; 85 86 if ((envent = environ_find(env, name)) != NULL) { 87 free(envent->value); 88 if (value != NULL) 89 envent->value = xstrdup(value); 90 else 91 envent->value = NULL; 92 } else { 93 envent = xmalloc(sizeof *envent); 94 envent->name = xstrdup(name); 95 if (value != NULL) 96 envent->value = xstrdup(value); 97 else 98 envent->value = NULL; 99 RB_INSERT(environ, env, envent); 100 } 101 } 102 103 /* Set an environment variable from a NAME=VALUE string. */ 104 void 105 environ_put(struct environ *env, const char *var) 106 { 107 char *name, *value; 108 109 value = strchr(var, '='); 110 if (value == NULL) 111 return; 112 value++; 113 114 name = xstrdup(var); 115 name[strcspn(name, "=")] = '\0'; 116 117 environ_set(env, name, value); 118 free(name); 119 } 120 121 /* Unset an environment variable. */ 122 void 123 environ_unset(struct environ *env, const char *name) 124 { 125 struct environ_entry *envent; 126 127 if ((envent = environ_find(env, name)) == NULL) 128 return; 129 RB_REMOVE(environ, env, envent); 130 free(envent->name); 131 free(envent->value); 132 free(envent); 133 } 134 135 /* 136 * Copy a space-separated list of variables from a destination into a source 137 * environment. 138 */ 139 void 140 environ_update(const char *vars, struct environ *srcenv, struct environ *dstenv) 141 { 142 struct environ_entry *envent; 143 char *copyvars, *var, *next; 144 145 copyvars = next = xstrdup(vars); 146 while ((var = strsep(&next, " ")) != NULL) { 147 if ((envent = environ_find(srcenv, var)) == NULL) 148 environ_set(dstenv, var, NULL); 149 else 150 environ_set(dstenv, envent->name, envent->value); 151 } 152 free(copyvars); 153 } 154 155 /* Push environment into the real environment - use after fork(). */ 156 void 157 environ_push(struct environ *env) 158 { 159 ARRAY_DECL(, char *) varlist; 160 struct environ_entry *envent; 161 char **varp, *var; 162 u_int i; 163 164 ARRAY_INIT(&varlist); 165 for (varp = environ; *varp != NULL; varp++) { 166 var = xstrdup(*varp); 167 var[strcspn(var, "=")] = '\0'; 168 ARRAY_ADD(&varlist, var); 169 } 170 for (i = 0; i < ARRAY_LENGTH(&varlist); i++) 171 unsetenv(ARRAY_ITEM(&varlist, i)); 172 ARRAY_FREE(&varlist); 173 174 RB_FOREACH(envent, environ, env) { 175 if (envent->value != NULL) 176 setenv(envent->name, envent->value, 1); 177 } 178 } 179