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 "go-alloc.h"
  13 #include "go-string.h"
  14
  15 /* Set the C environment from Go.  This is called by syscall.Setenv.  */
  16
  17 void setenv_c (struct __go_string, struct __go_string)
  18   __asm__ ("libgo_syscall.syscall.setenv_c");
  19
  20 void
  21 setenv_c (struct __go_string k, struct __go_string v)
  22 {
  23   const unsigned char *ks;
  24   unsigned char *kn;
  25   const unsigned char *vs;
  26   unsigned char *vn;
  27
  28   ks = k.__data;
  29   kn = NULL;
  30   vs = v.__data;
  31   vn = NULL;
  32
  33 #ifdef HAVE_SETENV
  34
  35   if (ks[k.__length] != 0)
  36     {
  37       kn = __go_alloc (k.__length + 1);
  38       __builtin_memcpy (kn, ks, k.__length);
  39       ks = kn;
  40     }
  41
  42   if (vs[v.__length] != 0)
  43     {
  44       vn = __go_alloc (v.__length + 1);
  45       __builtin_memcpy (vn, vs, v.__length);
  46       vs = vn;
  47     }
  48
  49   setenv ((const char *) ks, (const char *) vs, 1);
  50
  51 #else /* !defined(HAVE_SETENV) */
  52
  53   kn = malloc (k.__length + v.__length + 2);
  54   __builtin_memcpy (kn, ks, k.__length);
  55   kn[k.__length] = '=';
  56   __builtin_memcpy (kn + k.__length + 1, vs, v.__length);
  57   kn[k.__length + v.__length + 1] = '\0';
  58   putenv ((char *) kn);
  59
  60 #endif /* !defined(HAVE_SETENV) */
  61
  62   if (kn != NULL)
  63     __go_free (kn);
  64   if (vn != NULL)
  65     __go_free (vn);
  66 }