environ.c

   1 /* $Id: environ.c,v 1.3 2009-08-09 17:57:39 tcunha 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 void
  39 environ_init(struct environ *env)
  40 {
  41         RB_INIT(env);
  42 }
  43
  44 void
  45 environ_free(struct environ *env)
  46 {
  47         struct environ_entry    *envent;
  48
  49         while (!RB_EMPTY(env)) {
  50                 envent = RB_ROOT(env);
  51                 RB_REMOVE(environ, env, envent);
  52                 xfree(envent->name);
  53                 if (envent->value != NULL)
  54                         xfree(envent->value);
  55                 xfree(envent);
  56         }
  57 }
  58
  59 void
  60 environ_copy(struct environ *srcenv, struct environ *dstenv)
  61 {
  62         struct environ_entry    *envent;
  63
  64         RB_FOREACH(envent, environ, srcenv)
  65                 environ_set(dstenv, envent->name, envent->value);
  66 }
  67
  68 struct environ_entry *
  69 environ_find(struct environ *env, const char *name)
  70 {
  71         struct environ_entry    envent;
  72
  73         envent.name = (char *) name;
  74         return (RB_FIND(environ, env, &envent));
  75 }
  76
  77 void
  78 environ_set(struct environ *env, const char *name, const char *value)
  79 {
  80         struct environ_entry    *envent;
  81
  82         if ((envent = environ_find(env, name)) != NULL) {
  83                 if (envent->value != NULL)
  84                         xfree(envent->value);
  85                 if (value != NULL)
  86                         envent->value = xstrdup(value);
  87                 else
  88                         envent->value = NULL;
  89         } else {
  90                 envent = xmalloc(sizeof *envent);
  91                 envent->name = xstrdup(name);
  92                 if (value != NULL)
  93                         envent->value = xstrdup(value);
  94                 else
  95                         envent->value = NULL;
  96                 RB_INSERT(environ, env, envent);
  97         }
  98 }
  99
 100 void
 101 environ_put(struct environ *env, const char *var)
 102 {
 103         char            *name, *value;
 104
 105         value = strchr(var, '=');
 106         if (value == NULL)
 107                 return;
 108         value++;
 109
 110         name = xstrdup(var);
 111         name[strcspn(name, "=")] = '\0';
 112
 113         environ_set(env, name, value);
 114         xfree(name);
 115 }
 116
 117 void
 118 environ_unset(struct environ *env, const char *name)
 119 {
 120         struct environ_entry    *envent;
 121
 122         if ((envent = environ_find(env, name)) == NULL)
 123                 return;
 124         RB_REMOVE(environ, env, envent);
 125         xfree(envent->name);
 126         if (envent->value != NULL)
 127                 xfree(envent->value);
 128         xfree(envent);
 129 }
 130
 131 void
 132 environ_update(const char *vars, struct environ *srcenv, struct environ *dstenv)
 133 {
 134         struct environ_entry    *envent;
 135         char                    *copyvars, *var, *next;
 136
 137         copyvars = next = xstrdup(vars);
 138         while ((var = strsep(&next, " ")) != NULL) {
 139                 if ((envent = environ_find(srcenv, var)) == NULL)
 140                         environ_set(dstenv, var, NULL);
 141                 else
 142                         environ_set(dstenv, envent->name, envent->value);
 143         }
 144         xfree(copyvars);
 145 }