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/****************************************************************************
* eched/env_dupenv.c
*
* Copyright (C) 2007, 2009, 2011 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 <sys/types.h>
#include <sched.h>
#include <nuttx/kmalloc.h>
#include "os_internal.h"
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: dupenv
*
* Description:
* Copy the internal environment structure of a task. This is the action
* that is performed when a new task is created: The new task has a private,
* exact duplicate of the parent task's environment.
*
* Parameters:
* None
*
* Return Value:
* A pointer to a newly allocated copy of the specified TCB's environment
* structure with reference count equal to one.
*
* Assumptions:
* Not called from an interrupt handler.
*
****************************************************************************/
FAR environ_t *dupenv(FAR _TCB *ptcb)
{
environ_t *envp = NULL;
/* Pre-emption must be disabled throughout the following because the
* environment may be shared.
*/
sched_lock();
/* Does the parent task have an environment? */
if (ptcb->envp)
{
/* Yes..The parent task has an environment, duplicate it */
size_t envlen = ptcb->envp->ev_alloc
envp = (environ_t*)kmalloc(SIZEOF_ENVIRON_T( envlen ));
if (envp)
{
envp->ev_crefs = 1;
envp->ev_alloc = envlen;
memcmp( envp->ev_env, ptcb->envp->ev_env, envlen );
}
}
sched_unlock();
return envp;
}
#endif /* CONFIG_DISABLE_ENVIRON */
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