compiler/clib/putenv.c

   1 /*
   2     Copyright © 1995-2003, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     ANSI C function putenv().
   6 */
   7
   8 #include <proto/dos.h>
   9 #include <dos/var.h>
  10
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <ctype.h>
  14 #include <errno.h>
  15
  16 /*****************************************************************************
  17
  18     NAME */
  19 #include <stdlib.h>
  20
  21         int putenv (
  22
  23 /*  SYNOPSIS */
  24         const char *string)
  25
  26 /*  FUNCTION
  27         Change or add an environment variable.
  28
  29     INPUTS
  30         string - Is of the form "name=value", where name is the variable's
  31                  name and value is its value. In case the string is of the form
  32                  "name" then the variable is removed from the environment.
  33     RESULT
  34         The putenv() function returns zero on success, or -1 if an
  35         error occurs. In such a case the errno variable is set
  36         appropriately.
  37
  38     NOTES
  39         This function must not be used in a shared library.
  40         Conforming to BSD4.4 in that it makes a copy of the argument string.
  41
  42     EXAMPLE
  43
  44     BUGS
  45
  46     SEE ALSO
  47
  48     INTERNALS
  49
  50 ******************************************************************************/
  51 {
  52     char *name = NULL, *value = NULL, *ptr;
  53     int res = -1;
  54
  55     if (!string)
  56     {
  57         errno = EFAULT;
  58         goto err;
  59     }
  60
  61     name = strdup(string);
  62     if (!name) return -1;
  63
  64     for (ptr=name; *ptr!='\0' && *ptr!='='; ptr++)
  65     {
  66         if (isspace(*ptr))
  67         {
  68             errno = EINVAL;
  69             goto err;
  70         }
  71     }
  72
  73     /* No value means we have to delete the variable */
  74     if (*ptr == '\0')
  75         res = 0, unsetenv(name);
  76
  77     /* we might have a value to get */
  78     else
  79     {
  80         *ptr = '\0'; /* terminate the name string */
  81         value = ++ptr;
  82         res = setenv(name, value, 1);
  83     }
  84
  85 err:
  86     if (name)
  87         free(name);
  88
  89     return res;
  90 } /* putenv */
  91