1 /* $Id: environ.c,v 1.3 2011/08/17 18:48:36 jmmv 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 xfree(envent->name); 55 if (envent->value != NULL) 56 xfree(envent->value); 57 xfree(envent); 58 } 59 } 60 61 /* Copy one environment into another. */ 62 void 63 environ_copy(struct environ *srcenv, struct environ *dstenv) 64 { 65 struct environ_entry *envent; 66 67 RB_FOREACH(envent, environ, srcenv) 68 environ_set(dstenv, envent->name, envent->value); 69 } 70 71 /* Find an environment variable. */ 72 struct environ_entry * 73 environ_find(struct environ *env, const char *name) 74 { 75 struct environ_entry envent; 76 77 envent.name = __UNCONST(name); 78 return (RB_FIND(environ, env, &envent)); 79 } 80 81 /* Set an environment variable. */ 82 void 83 environ_set(struct environ *env, const char *name, const char *value) 84 { 85 struct environ_entry *envent; 86 87 if ((envent = environ_find(env, name)) != NULL) { 88 if (envent->value != NULL) 89 xfree(envent->value); 90 if (value != NULL) 91 envent->value = xstrdup(value); 92 else 93 envent->value = NULL; 94 } else { 95 envent = xmalloc(sizeof *envent); 96 envent->name = xstrdup(name); 97 if (value != NULL) 98 envent->value = xstrdup(value); 99 else 100 envent->value = NULL; 101 RB_INSERT(environ, env, envent); 102 } 103 } 104 105 /* Set an environment variable from a NAME=VALUE string. */ 106 void 107 environ_put(struct environ *env, const char *var) 108 { 109 char *name, *value; 110 111 value = strchr(var, '='); 112 if (value == NULL) 113 return; 114 value++; 115 116 name = xstrdup(var); 117 name[strcspn(name, "=")] = '\0'; 118 119 environ_set(env, name, value); 120 xfree(name); 121 } 122 123 /* Unset an environment variable. */ 124 void 125 environ_unset(struct environ *env, const char *name) 126 { 127 struct environ_entry *envent; 128 129 if ((envent = environ_find(env, name)) == NULL) 130 return; 131 RB_REMOVE(environ, env, envent); 132 xfree(envent->name); 133 if (envent->value != NULL) 134 xfree(envent->value); 135 xfree(envent); 136 } 137 138 /* 139 * Copy a space-separated list of variables from a destination into a source 140 * environment. 141 */ 142 void 143 environ_update(const char *vars, struct environ *srcenv, struct environ *dstenv) 144 { 145 struct environ_entry *envent; 146 char *copyvars, *var, *next; 147 148 copyvars = next = xstrdup(vars); 149 while ((var = strsep(&next, " ")) != NULL) { 150 if ((envent = environ_find(srcenv, var)) == NULL) 151 environ_set(dstenv, var, NULL); 152 else 153 environ_set(dstenv, envent->name, envent->value); 154 } 155 xfree(copyvars); 156 } 157 158 /* Push environment into the real environment - use after fork(). */ 159 void 160 environ_push(struct environ *env) 161 { 162 ARRAY_DECL(, char *) varlist; 163 struct environ_entry *envent; 164 char **varp, *var; 165 u_int i; 166 167 ARRAY_INIT(&varlist); 168 for (varp = environ; *varp != NULL; varp++) { 169 var = xstrdup(*varp); 170 var[strcspn(var, "=")] = '\0'; 171 ARRAY_ADD(&varlist, var); 172 } 173 for (i = 0; i < ARRAY_LENGTH(&varlist); i++) 174 unsetenv(ARRAY_ITEM(&varlist, i)); 175 ARRAY_FREE(&varlist); 176 177 RB_FOREACH(envent, environ, env) { 178 if (envent->value != NULL) 179 setenv(envent->name, envent->value, 1); 180 } 181 } 182