129 lines
3.9 KiB
C
129 lines
3.9 KiB
C
/****************************************************************************
|
|
* sched/environ/env_getenv.c
|
|
*
|
|
* Copyright (C) 2007, 2008, 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 <stdlib.h>
|
|
#include <errno.h>
|
|
|
|
#include "sched/sched.h"
|
|
#include "environ/environ.h"
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: getenv
|
|
*
|
|
* Description:
|
|
* The getenv() function searches the environment list for a string that
|
|
* matches the string pointed to by name.
|
|
*
|
|
* Input Parameters:
|
|
* name - The name of the variable to find.
|
|
*
|
|
* Returned Value:
|
|
* The value of the valiable (read-only) or NULL on failure
|
|
*
|
|
* Assumptions:
|
|
* Not called from an interrupt handler
|
|
*
|
|
****************************************************************************/
|
|
|
|
FAR char *getenv(FAR const char *name)
|
|
{
|
|
FAR struct tcb_s *rtcb;
|
|
FAR struct task_group_s *group;
|
|
FAR char *pvar;
|
|
FAR char *pvalue = NULL;
|
|
int ret = OK;
|
|
|
|
/* Verify that a string was passed */
|
|
|
|
if (name == NULL)
|
|
{
|
|
ret = EINVAL;
|
|
goto errout;
|
|
}
|
|
|
|
/* Get a reference to the thread-private environ in the TCB. */
|
|
|
|
sched_lock();
|
|
rtcb = this_task();
|
|
group = rtcb->group;
|
|
|
|
/* Check if the variable exists */
|
|
|
|
if (group == NULL || (pvar = env_findvar(group, name)) == NULL)
|
|
{
|
|
ret = ENOENT;
|
|
goto errout_with_lock;
|
|
}
|
|
|
|
/* It does! Get the value sub-string from the name=value string */
|
|
|
|
pvalue = strchr(pvar, '=');
|
|
if (pvalue == NULL)
|
|
{
|
|
/* The name=value string has no '=' This is a bug! */
|
|
|
|
ret = EINVAL;
|
|
goto errout_with_lock;
|
|
}
|
|
|
|
/* Adjust the pointer so that it points to the value right after the '=' */
|
|
|
|
pvalue++;
|
|
sched_unlock();
|
|
return pvalue;
|
|
|
|
errout_with_lock:
|
|
sched_unlock();
|
|
errout:
|
|
set_errno(ret);
|
|
return NULL;
|
|
}
|
|
|
|
#endif /* CONFIG_DISABLE_ENVIRON */
|