/****************************************************************************
* sched/env_unsetenv.c
*
* Copyright (C) 2007, 2009, 2011, 2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#ifndef CONFIG_DISABLE_ENVIRON
#include <sched.h>
#include <string.h>
#include <errno.h>
#include <nuttx/kmalloc.h>
#include "os_internal.h"
#include "env_internal.h"
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: unsetenv
*
* Description:
* The unsetenv() function deletes the variable name from the environment.
*
* Parameters:
* name - The name of the variable to delete
*
* Return Value:
* Zero on success
*
* Assumptions:
* Not called from an interrupt handler
*
****************************************************************************/
int unsetenv(FAR const char *name)
{
FAR struct tcb_s *rtcb = (FAR struct tcb_s*)g_readytorun.head;
FAR struct task_group_s *group = rtcb->group;
FAR char *pvar;
FAR char *newenvp;
int newsize;
int ret = OK;
DEBUGASSERT(name && group);
/* Check if the variable exists */
sched_lock();
if (group && (pvar = env_findvar(group, name)) != NULL)
{
/* It does! Remove the name=value pair from the environment. */
(void)env_removevar(group, pvar);
/* Reallocate the new environment buffer */
newsize = group->tg_envsize;
newenvp = (FAR char *)kurealloc(group->tg_envp, newsize);
if (!newenvp)
{
set_errno(ENOMEM);
ret = ERROR;
}
else
{
/* Save the new environment pointer (it might have changed due to
* reallocation.
*/
group->tg_envp = newenvp;
}
}
sched_unlock();
return ret;
}
#endif /* CONFIG_DISABLE_ENVIRON */
