libgo/runtime/go-setenv.c

   1 /* go-setenv.c -- set the C environment from Go.
   2
   3    Copyright 2011 The Go Authors. All rights reserved.
   4    Use of this source code is governed by a BSD-style
   5    license that can be found in the LICENSE file.  */
   6
   7 #include "config.h"
   8
   9 #include <stddef.h>
  10 #include <stdlib.h>
  11
  12 #include "runtime.h"
  13
  14 /* Set the C environment from Go.  This is called by syscall.Setenv.  */
  15
  16 void setenv_c (String, String) __asm__ (GOSYM_PREFIX "syscall.setenv_c");
  17
  18 void
  19 setenv_c (String k, String v)
  20 {
  21   const byte *ks;
  22   unsigned char *kn;
  23   const byte *vs;
  24   unsigned char *vn;
  25
  26   ks = k.str;
  27   if (ks == NULL)
  28     ks = (const byte *) "";
  29   kn = NULL;
  30
  31   vs = v.str;
  32   if (vs == NULL)
  33     vs = (const byte *) "";
  34   vn = NULL;
  35
  36 #ifdef HAVE_SETENV
  37
  38   if (ks[k.len] != 0)
  39     {
  40       kn = malloc (k.len + 1);
  41       if (kn == NULL)
  42         runtime_throw ("out of malloc memory");
  43       __builtin_memcpy (kn, ks, k.len);
  44       kn[k.len] = '\0';
  45       ks = kn;
  46     }
  47
  48   if (vs[v.len] != 0)
  49     {
  50       vn = malloc (v.len + 1);
  51       if (vn == NULL)
  52         runtime_throw ("out of malloc memory");
  53       __builtin_memcpy (vn, vs, v.len);
  54       vn[v.len] = '\0';
  55       vs = vn;
  56     }
  57
  58   setenv ((const char *) ks, (const char *) vs, 1);
  59
  60 #else /* !defined(HAVE_SETENV) */
  61
  62   len = k.len + v.len + 2;
  63   kn = malloc (len);
  64   if (kn == NULL)
  65     runtime_throw ("out of malloc memory");
  66   __builtin_memcpy (kn, ks, k.len);
  67   kn[k.len] = '=';
  68   __builtin_memcpy (kn + k.len + 1, vs, v.len);
  69   kn[k.len + v.len + 1] = '\0';
  70   putenv ((char *) kn);
  71   kn = NULL; /* putenv takes ownership of the string.  */
  72
  73 #endif /* !defined(HAVE_SETENV) */
  74
  75   if (kn != NULL)
  76     free (kn);
  77   if (vn != NULL)
  78     free (vn);
  79 }