compiler/clib/__env.c

   1 /*
   2     Copyright © 1995-2003, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Internal functions for environment variables handling.
   6 */
   7
   8 #include "__arosc_privdata.h"
   9
  10 #include <stdlib.h>
  11 #include <strings.h>
  12 #include <proto/exec.h>
  13
  14 #include "__env.h"
  15
  16 static __env_item *__env_newvar(const char *name, int valuesize)
  17 {
  18     __env_item *item;
  19
  20     item = malloc(sizeof(__env_item));
  21     if (!item) goto err1;
  22
  23     item->name = strdup(name);
  24     if (!item->name) goto err2;
  25
  26     item->value = malloc(valuesize);
  27     if (!item->value) goto err3;
  28
  29     item->next = NULL;
  30
  31     return item;
  32
  33 err3:
  34     free(item->name);
  35 err2:
  36     free(item);
  37 err1:
  38     return NULL;
  39 }
  40
  41 static __env_item **internal_findvar(register const char *name)
  42 {
  43
  44    __env_item **curr;
  45
  46    for (
  47        curr = &__env_list;
  48        *curr && strcmp((*curr)->name, name);
  49        curr = &((*curr)->next)
  50    );
  51
  52   return curr;
  53 }
  54
  55 /*
  56   Allocates space for a variable with name 'name' returning a pointer to it.
  57   If a variable with this name already exists then returns a pointer to that
  58   variable.
  59
  60   Returns NULL on error.
  61 */
  62 __env_item *__env_getvar(const char *name, int valuesize)
  63 {
  64     register __env_item **curr;
  65
  66     curr = internal_findvar(name);
  67
  68     if (*curr)
  69     {
  70         if (strlen((*curr)->value) < valuesize)
  71         {
  72             free((*curr)->value);
  73             (*curr)->value = malloc(valuesize);
  74
  75             if (!(*curr)->value)
  76             {
  77                 __env_item *tmp = (*curr)->next;
  78
  79                 free(*curr);
  80                 *curr = tmp;
  81             }
  82         }
  83     }
  84     else
  85     {
  86         *curr = __env_newvar(name, valuesize);
  87     }
  88
  89     return *curr;
  90 }
  91
  92 void __env_delvar(const char *name)
  93 {
  94     register __env_item **curr;
  95
  96     curr = internal_findvar(name);
  97
  98     if (*curr)
  99     {
 100         register __env_item *tmp = *curr;
 101
 102         *curr = (*curr)->next;
 103
 104         free(tmp->name);
 105         free(tmp->value);
 106         free(tmp);
 107     }
 108 }