NetBSD/gnu/usr.bin/groff/libgroff/putenv.c

97 lines
2.4 KiB
C

/* Copyright (C) 1991 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
/* Hacked slightly by jjc@jclark.com for groff. */
#include <string.h>
#ifdef __STDC__
#include <stddef.h>
typedef void *PTR;
typedef size_t SIZE_T;
#else /* not __STDC__ */
typedef char *PTR;
typedef int SIZE_T;
#endif /* not __STDC__ */
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#else /* not HAVE_STDLIB_H */
PTR malloc();
#endif /* not HAVE_STDLIB_H */
#ifndef NULL
#define NULL 0
#endif
extern char **environ;
/* Put STRING, which is of the form "NAME=VALUE", in the environment. */
int putenv(string)
char *string;
{
char *name_end = strchr(string, '=');
SIZE_T size;
char **ep;
if (name_end == NULL)
{
/* Remove the variable from the environment. */
size = strlen(string);
for (ep = environ; *ep != NULL; ++ep)
if (!strncmp(*ep, string, size) && (*ep)[size] == '=')
{
while (ep[1] != NULL)
{
ep[0] = ep[1];
++ep;
}
*ep = NULL;
return 0;
}
}
size = 0;
for (ep = environ; *ep != NULL; ++ep)
if (!strncmp(*ep, string, name_end - string)
&& (*ep)[name_end - string] == '=')
break;
else
++size;
if (*ep == NULL)
{
static char **last_environ = NULL;
char **new_environ = (char **) malloc((size + 2) * sizeof(char *));
if (new_environ == NULL)
return -1;
(void) memcpy((PTR) new_environ, (PTR) environ, size * sizeof(char *));
new_environ[size] = (char *) string;
new_environ[size + 1] = NULL;
if (last_environ != NULL)
free((PTR) last_environ);
last_environ = new_environ;
environ = new_environ;
}
else
*ep = (char *) string;
return 0;
}