gnucash/lib/libc/setenv.c
David Hampton 4b04137e7d Never include "config.h" from a header file. Doing so makes it nigh
impossible to override configuration settings.


git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@13549 57a11ea4-9604-0410-9ed3-97b8803252fd
2006-03-09 05:51:07 +00:00

93 lines
3.0 KiB
C

/********************************************************************\
* File: setenv.c
* Renamed from: core-utils.c
*
* Copyright (C) 2001 Linux Developers Group
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
\********************************************************************/
#include "config.h"
#include <glib.h>
#include <glib/gprintf.h>
#include <stdlib.h>
#include <string.h>
#include "setenv.h"
/* This setenv() papers over the brokenness of of systems that only
* have putenv() which takes ownership of the pointer you give it,
* making it *very* difficult, if not impossible to avoid memory
* leaks. Note that right now, on systems that have setenv, this is
* just setenv, and on other systems, we just leave the memory leak.
* Later, we may try to make things a little better by keeping track
* of the pointers we call putenv on in a hash table and if someone
* calls gnc_setenv on an envt var that we've previously set, then
* we'll free it after the change. However, given the sloppy
* semantics (or docs) for putenv, it's not even clear that this is
* OK, since it's not clear that people aren't allowed to keep the
* pointer from getenv around, as long as they don't try to modify
* it... <shrug> */
#ifndef HAVE_SETENV
int
setenv(const char *name, const char *value, int overwrite)
{
const char *old_value = getenv(name);
int result = 0;
if ((name == NULL) || (value == NULL)) return -1;
if(overwrite || (!old_value))
{
char *new_value = g_strdup_printf("%s=%s", name, value);
if(putenv(new_value) != 0) result = -1;
if(old_value)
{
/* for now, do nothing, but it would be nice if we could figure
out a safe way to reclaim any memory that *we* allocated,
taking in to account whether or not other code (in other
system libs) is allowed to have cached a pointer into the
value via getenv -- is that kosher?
Also we have to *know* that we allocated the memory.
*/
}
}
return result;
}
int
unsetenv(const char *name)
{
int result = 0;
char *putenv_str;
if(name == NULL) return -1;
if(strchr(name, '=') != NULL) return -1;
if(*name == '\0') return -1;
putenv_str = g_strdup_printf("%s=", name);
if(!putenv_str) return -1;
result = putenv(putenv_str);
g_free(putenv_str);
return result;
}
#endif