src/util/env.c

   1 /* Environment variables handling */
   2
   3 #ifdef HAVE_CONFIG_H
   4 #include "config.h"
   5 #endif
   6
   7 #include <ctype.h>
   8 #include <errno.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12
  13 #include "elinks.h"
  14
  15 #include "util/env.h"
  16 #include "util/memory.h"
  17 #include "util/string.h"
  18
  19 /* Set @name environment variable to @value or a substring of it:
  20  * On success, it returns 0.
  21  * If @value is NULL and on error, it returns -1.
  22  * If @length >= 0 and smaller than true @value length, it will
  23  * set @name to specified substring of @value.
  24  */
  25 int
  26 env_set(unsigned char *name, unsigned char *value, int length)
  27 {
  28         int true_length, substring = 0;
  29
  30         if (!value || !name || !*name) return -1;
  31
  32         true_length = strlen(value);
  33         substring = (length >= 0 && length < true_length);
  34         if (!substring) length = true_length;
  35
  36 #if defined(HAVE_SETENV)
  37         {
  38                 int ret, allocated = 0;
  39
  40                 if (substring) {
  41                         /* Copy the substring. */
  42                         value = memacpy(value, length);
  43                         if (!value) return -1;
  44                         allocated = 1;
  45                 }
  46
  47                 ret = setenv(name, value, 1);
  48                 if (allocated) mem_free(value);
  49                 return ret;
  50         }
  51
  52 #elif defined(HAVE_PUTENV)
  53
  54         {
  55                 int namelen = strlen(name);
  56                 char *s = malloc(namelen + length + 2);
  57
  58                 if (!s) return -1;
  59                 memcpy(s, name, namelen);
  60                 s[namelen] = '=';
  61                 memcpy(&s[namelen + 1], value, length);
  62                 s[namelen + 1 + length] = '\0';
  63
  64                 /* @s is never freed by us, this is intentional.
  65                  * --> Possible memleaks on repeated use of
  66                  * this function. */
  67                 return putenv(s);
  68         }
  69
  70 #else
  71         /* XXX: what to do ?? */
  72         return -1;
  73 #endif
  74 }