incubator-nuttx/sched/environ/env_foreach.c

104 lines
3.0 KiB
C

/****************************************************************************
* sched/environ/env_foreach.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#ifndef CONFIG_DISABLE_ENVIRON
#include <stdbool.h>
#include <string.h>
#include <sched.h>
#include <assert.h>
#include <nuttx/environ.h>
#include "environ/environ.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: env_foreach
*
* Description:
* Visit each name-value pair in the environment.
*
* Input Parameters:
* group - The task group containing environment array to be searched.
* cb - The callback function to be invoked for each environment
* variable.
*
* Returned Value:
* Zero if the all environment variables have been traversed. A non-zero
* value means that the callback function requested early termination by
* returning a nonzero value.
*
* Assumptions:
* - Not called from an interrupt handler
* - Pre-emptions is disabled by caller
*
****************************************************************************/
int env_foreach(FAR struct task_group_s *group,
env_foreach_t cb,
FAR void *arg)
{
int ret = OK;
size_t i;
/* Verify input parameters */
DEBUGASSERT(group != NULL && cb != NULL);
if (group->tg_envp == NULL)
{
return ret;
}
for (i = 0; group->tg_envp[i] != NULL; i++)
{
/* Perform the callback */
ret = cb(arg, group->tg_envp[i]);
/* Terminate the traversal early if the callback so requests by
* returning a non-zero value.
*/
if (ret != 0)
{
break;
}
}
DEBUGASSERT(ret != OK || group->tg_envc == i);
return ret;
}
#endif /* CONFIG_DISABLE_ENVIRON */