/* Copyright (c) 2011, The Linux Foundation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of The Linux Foundation 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 "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
* 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.
*/
#ifndef __MSG_Q_H__
#define __MSG_Q_H__
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
#include <stdlib.h>
/** Linked List Return Codes */
typedef enum
{
eMSG_Q_SUCCESS = 0,
/**< Request was successful. */
eMSG_Q_FAILURE_GENERAL = -1,
/**< Failed because of a general failure. */
eMSG_Q_INVALID_PARAMETER = -2,
/**< Failed because the request contained invalid parameters. */
eMSG_Q_INVALID_HANDLE = -3,
/**< Failed because an invalid handle was specified. */
eMSG_Q_UNAVAILABLE_RESOURCE = -4,
/**< Failed because an there were not enough resources. */
eMSG_Q_INSUFFICIENT_BUFFER = -5,
/**< Failed because an the supplied buffer was too small. */
}msq_q_err_type;
/*===========================================================================
FUNCTION msg_q_init
DESCRIPTION
Initializes internal structures for message queue.
msg_q_data: pointer to an opaque Q handle to be returned; NULL if fails
DEPENDENCIES
N/A
RETURN VALUE
Look at error codes above.
SIDE EFFECTS
N/A
===========================================================================*/
msq_q_err_type msg_q_init(void** msg_q_data);
/*===========================================================================
FUNCTION msg_q_init2
DESCRIPTION
Initializes internal structures for message queue.
DEPENDENCIES
N/A
RETURN VALUE
opaque handle to the Q created; NULL if create fails
SIDE EFFECTS
N/A
===========================================================================*/
const void* msg_q_init2();
/*===========================================================================
FUNCTION msg_q_destroy
DESCRIPTION
Releases internal structures for message queue.
msg_q_data: State of message queue to be released.
DEPENDENCIES
N/A
RETURN VALUE
Look at error codes above.
SIDE EFFECTS
N/A
===========================================================================*/
msq_q_err_type msg_q_destroy(void** msg_q_data);
/*===========================================================================
FUNCTION msg_q_snd
DESCRIPTION
Sends data to the message queue. The passed in data pointer
is not modified or freed. Passed in msg_obj is expected to live throughout
the use of the msg_q (i.e. data is not allocated internally)
msg_q_data: Message Queue to add the element to.
msgp: Pointer to data to add into message queue.
dealloc: Function used to deallocate memory for this element. Pass NULL
if you do not want data deallocated during a flush operation
DEPENDENCIES
N/A
RETURN VALUE
Look at error codes above.
SIDE EFFECTS
N/A
===========================================================================*/
msq_q_err_type msg_q_snd(void* msg_q_data, void* msg_obj, void (*dealloc)(void*));
/*===========================================================================
FUNCTION msg_q_rcv
DESCRIPTION
Retrieves data from the message queue. msg_obj is the oldest message received
and pointer is simply removed from message queue.
msg_q_data: Message Queue to copy data from into msgp.
msg_obj: Pointer to space to copy msg_q contents to.
DEPENDENCIES
N/A
RETURN VALUE
Look at error codes above.
SIDE EFFECTS
N/A
===========================================================================*/
msq_q_err_type msg_q_rcv(void* msg_q_data, void** msg_obj);
/*===========================================================================
FUNCTION msg_q_rmv
DESCRIPTION
Remove data from the message queue. msg_obj is the oldest message received
and pointer is simply removed from message queue.
msg_q_data: Message Queue to copy data from into msgp.
msg_obj: Pointer to space to copy msg_q contents to.
DEPENDENCIES
N/A
RETURN VALUE
Look at error codes above.
SIDE EFFECTS
N/A
===========================================================================*/
msq_q_err_type msg_q_rmv(void* msg_q_data, void** msg_obj);
/*===========================================================================
FUNCTION msg_q_flush
DESCRIPTION
Function removes all elements from the message queue.
msg_q_data: Message Queue to remove elements from.
DEPENDENCIES
N/A
RETURN VALUE
Look at error codes above.
SIDE EFFECTS
N/A
===========================================================================*/
msq_q_err_type msg_q_flush(void* msg_q_data);
/*===========================================================================
FUNCTION msg_q_unblock
DESCRIPTION
This function will stop use of the message queue. All waiters will wake up
and likely receive nothing from the queue resulting in a negative return
value. The message queue can no longer be used until it is destroyed
and initialized again after calling this function.
msg_q_data: Message queue to unblock.
DEPENDENCIES
N/A
RETURN VALUE
Look at error codes above.
SIDE EFFECTS
N/A
===========================================================================*/
msq_q_err_type msg_q_unblock(void* msg_q_data);
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* __MSG_Q_H__ */
