713 lines
27 KiB
C
713 lines
27 KiB
C
/****************************************************************************
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* include/nuttx/mqueue.h
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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#ifndef ___INCLUDE_NUTTX_MQUEUE_H
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#define ___INCLUDE_NUTTX_MQUEUE_H
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <nuttx/compiler.h>
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#include <nuttx/fs/fs.h>
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#include <nuttx/signal.h>
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#include <nuttx/list.h>
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#include <sys/types.h>
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#include <stdint.h>
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#include <stdbool.h>
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#include <mqueue.h>
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#include <poll.h>
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#if CONFIG_MQ_MAXMSGSIZE > 0
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/****************************************************************************
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* Pre-processor Definitions
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****************************************************************************/
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/* Most internal nxmq_* interfaces are not available in the user space in
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* PROTECTED and KERNEL builds. In that context, the application message
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* queue interfaces must be used. The differences between the two sets of
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* interfaces are: (1) the nxmq_* interfaces do not cause cancellation
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* points and (2) they do not modify the errno variable.
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*
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* This is only important when compiling libraries (libc or libnx) that are
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* used both by the OS (libkc.a and libknx.a) or by the applications
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* (libc.a and libnx.a). In that case, the correct interface must be
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* used for the build context.
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*
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* REVISIT: In the flat build, the same functions must be used both by
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* the OS and by applications. We have to use the normal user functions
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* in this case or we will fail to set the errno or fail to create the
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* cancellation point.
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*/
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#if !defined(CONFIG_BUILD_FLAT) && defined(__KERNEL__)
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# define _MQ_OPEN nxmq_open
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# define _MQ_CLOSE(d) nxmq_close(d)
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# define _MQ_UNLINK(n) nxmq_unlink(n)
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# define _MQ_SEND(d,m,l,p) nxmq_send(d,m,l,p)
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# define _MQ_TIMEDSEND(d,m,l,p,t) nxmq_timedsend(d,m,l,p,t)
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# define _MQ_RECEIVE(d,m,l,p) nxmq_receive(d,m,l,p)
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# define _MQ_TIMEDRECEIVE(d,m,l,p,t) nxmq_timedreceive(d,m,l,p,t)
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#else
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# define _MQ_OPEN mq_open
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# define _MQ_CLOSE(d) mq_close(d)
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# define _MQ_UNLINK(n) mq_unlink(n)
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# define _MQ_SEND(d,m,l,p) mq_send(d,m,l,p)
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# define _MQ_TIMEDSEND(d,m,l,p,t) mq_timedsend(d,m,l,p,t)
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# define _MQ_RECEIVE(d,m,l,p) mq_receive(d,m,l,p)
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# define _MQ_TIMEDRECEIVE(d,m,l,p,t) mq_timedreceive(d,m,l,p,t)
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#endif
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#if CONFIG_FS_MQUEUE_NPOLLWAITERS > 0
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# define nxmq_pollnotify(msgq, eventset) \
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poll_notify(msgq->fds, CONFIG_FS_MQUEUE_NPOLLWAITERS, eventset)
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#else
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# define nxmq_pollnotify(msgq, eventset)
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#endif
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# define MQ_WNELIST(cmn) (&((cmn).waitfornotempty))
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# define MQ_WNFLIST(cmn) (&((cmn).waitfornotfull))
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/****************************************************************************
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* Public Type Declarations
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****************************************************************************/
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/* Common prologue of all message queue structures. */
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struct mqueue_cmn_s
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{
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dq_queue_t waitfornotempty; /* Task list waiting for not empty */
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dq_queue_t waitfornotfull; /* Task list waiting for not full */
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int16_t nwaitnotfull; /* Number tasks waiting for not full */
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int16_t nwaitnotempty; /* Number tasks waiting for not empty */
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};
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/* This structure defines a message queue */
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struct mqueue_inode_s
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{
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struct mqueue_cmn_s cmn; /* Common prologue */
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FAR struct inode *inode; /* Containing inode */
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struct list_node msglist; /* Prioritized message list */
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int16_t maxmsgs; /* Maximum number of messages in the queue */
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int16_t nmsgs; /* Number of message in the queue */
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#if CONFIG_MQ_MAXMSGSIZE < 256
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uint8_t maxmsgsize; /* Max size of message in message queue */
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#else
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uint16_t maxmsgsize; /* Max size of message in message queue */
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#endif
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#ifndef CONFIG_DISABLE_MQUEUE_NOTIFICATION
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pid_t ntpid; /* Notification: Receiving Task's PID */
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struct sigevent ntevent; /* Notification description */
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struct sigwork_s ntwork; /* Notification work */
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#endif
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FAR struct pollfd *fds[CONFIG_FS_MQUEUE_NPOLLWAITERS];
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};
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/****************************************************************************
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* Public Data
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****************************************************************************/
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/****************************************************************************
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* Public Function Prototypes
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****************************************************************************/
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#ifdef __cplusplus
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#define EXTERN extern "C"
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extern "C"
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{
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#else
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#define EXTERN extern
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#endif
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struct tcb_s; /* Forward reference */
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struct mq_attr; /* Forward reference */
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struct timespec; /* Forward reference */
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struct task_group_s; /* Forward reference */
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/****************************************************************************
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* Name: nxmq_open
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*
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* Description:
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* This function establish a connection between a named message queue and
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* the calling task. This is an internal OS interface. It is functionally
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* equivalent to mq_open() except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_open() for a more complete description of the
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* behavior of this function
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*
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* Input Parameters:
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* mq_name - Name of the queue to open
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* oflags - open flags
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* Optional parameters. When the O_CREAT flag is specified, two optional
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* parameters are expected:
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*
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* 1. mode_t mode, and
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* 2. struct mq_attr *attr. The mq_maxmsg attribute
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* is used at the time that the message queue is
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* created to determine the maximum number of
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* messages that may be placed in the message queue.
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* It follows the NuttX internal error return policy: Zero (OK) is
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* returned on success, mqdes point to the new message queue descriptor.
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* A negated errno value is returned on failure.
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*
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****************************************************************************/
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mqd_t nxmq_open(FAR const char *mq_name, int oflags, ...);
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/****************************************************************************
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* Name: nxmq_close
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*
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* Description:
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* This is an internal OS interface. It is functionally equivalent to
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* mq_close() except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_close() for a more complete description of the
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* behavior of this function
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*
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* Input Parameters:
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* mqdes - Message queue descriptor.
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* It follows the NuttX internal error return policy: Zero (OK) is
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* returned on success. A negated errno value is returned on failure.
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*
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****************************************************************************/
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int nxmq_close(mqd_t mqdes);
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/****************************************************************************
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* Name: nxmq_unlink
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*
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* Description:
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* This is an internal OS interface. It is functionally equivalent to
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* mq_unlink() except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_unlink() for a more complete description of the
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* behavior of this function
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*
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* Input Parameters:
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* mq_name - Name of the message queue
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* It follows the NuttX internal error return policy: Zero (OK) is
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* returned on success. A negated errno value is returned on failure.
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*
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****************************************************************************/
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int nxmq_unlink(FAR const char *mq_name);
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/****************************************************************************
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* Name: nxmq_send
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*
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* Description:
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* This function adds the specified message (msg) to the message queue
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* (mqdes). This is an internal OS interface. It is functionally
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* equivalent to mq_send() except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_send() for a more complete description of the
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* behavior of this function
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*
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* Input Parameters:
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* mqdes - Message queue descriptor
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* msg - Message to send
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* msglen - The length of the message in bytes
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* prio - The priority of the message
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* It follows the NuttX internal error return policy: Zero (OK) is
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* returned on success. A negated errno value is returned on failure.
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* (see mq_send() for the list list valid return values).
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*
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****************************************************************************/
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int nxmq_send(mqd_t mqdes, FAR const char *msg, size_t msglen,
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unsigned int prio);
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/****************************************************************************
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* Name: nxmq_timedsend
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*
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* Description:
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* This function adds the specified message (msg) to the message queue
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* (mqdes). nxmq_timedsend() behaves just like mq_send(), except that if
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* the queue is full and the O_NONBLOCK flag is not enabled for the
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* message queue description, then abstime points to a structure which
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* specifies a ceiling on the time for which the call will block.
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*
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* nxmq_timedsend() is functionally equivalent to mq_timedsend() except
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* that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_timedsend() for a more complete description of the
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* behavior of this function
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*
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* Input Parameters:
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* mqdes - Message queue descriptor
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* msg - Message to send
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* msglen - The length of the message in bytes
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* prio - The priority of the message
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* abstime - the absolute time to wait until a timeout is decleared
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* It follows the NuttX internal error return policy: Zero (OK) is
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* returned on success. A negated errno value is returned on failure.
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* (see mq_timedsend() for the list list valid return values).
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*
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* EAGAIN The queue was empty, and the O_NONBLOCK flag was set for the
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* message queue description referred to by mqdes.
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* EINVAL Either msg or mqdes is NULL or the value of prio is invalid.
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* EPERM Message queue opened not opened for writing.
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* EMSGSIZE 'msglen' was greater than the maxmsgsize attribute of the
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* message queue.
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* EINTR The call was interrupted by a signal handler.
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*
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****************************************************************************/
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int nxmq_timedsend(mqd_t mqdes, FAR const char *msg, size_t msglen,
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unsigned int prio, FAR const struct timespec *abstime);
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/****************************************************************************
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* Name: nxmq_receive
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*
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* Description:
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* This function receives the oldest of the highest priority messages
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* from the message queue specified by "mqdes." This is an internal OS
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* interface. It is functionally equivalent to mq_receive except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_receive() for a more complete description of the
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* behavior of this function
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*
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* Input Parameters:
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* mqdes - Message Queue Descriptor
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* msg - Buffer to receive the message
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* msglen - Size of the buffer in bytes
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* prio - If not NULL, the location to store message priority.
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* It follows the NuttX internal error return policy: Zero (OK) is
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* returned on success. A negated errno value is returned on failure.
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* (see mq_receive() for the list list valid return values).
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*
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****************************************************************************/
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ssize_t nxmq_receive(mqd_t mqdes, FAR char *msg, size_t msglen,
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FAR unsigned int *prio);
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/****************************************************************************
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* Name: nxmq_timedreceive
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*
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* Description:
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* This function receives the oldest of the highest priority messages from
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* the message queue specified by "mqdes." If the message queue is empty
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* and O_NONBLOCK was not set, nxmq_timedreceive() will block until a
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* message is added to the message queue (or until a timeout occurs).
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*
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* nxmq_timedreceive() is an internal OS interface. It is functionally
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* equivalent to mq_timedreceive() except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_timedreceive() for a more complete description of
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* the behavior of this function
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*
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* Input Parameters:
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* mqdes - Message Queue Descriptor
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* msg - Buffer to receive the message
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* msglen - Size of the buffer in bytes
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* prio - If not NULL, the location to store message priority.
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* abstime - the absolute time to wait until a timeout is declared.
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* It follows the NuttX internal error return policy: Zero (OK) is
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* returned on success. A negated errno value is returned on failure.
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* (see mq_timedreceive() for the list list valid return values).
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*
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****************************************************************************/
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ssize_t nxmq_timedreceive(mqd_t mqdes, FAR char *msg, size_t msglen,
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FAR unsigned int *prio,
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FAR const struct timespec *abstime);
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/****************************************************************************
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* Name: nxmq_free_msgq
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*
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* Description:
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* This function deallocates an initialized message queue structure.
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* First, it deallocates all of the queued messages in the message
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* queue. It is assumed that this message queue is fully unlinked
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* and closed so that no thread will attempt to access it while it
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* is being deleted.
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*
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* Input Parameters:
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* msgq - Named message queue to be freed
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*
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* Returned Value:
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* None
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*
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****************************************************************************/
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void nxmq_free_msgq(FAR struct mqueue_inode_s *msgq);
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/****************************************************************************
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* Name: nxmq_alloc_msgq
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*
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* Description:
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* This function implements a part of the POSIX message queue open logic.
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* It allocates and initializes a struct mqueue_inode_s structure.
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*
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* Input Parameters:
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* attr - The mq_maxmsg attribute is used at the time that the message
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* queue is created to determine the maximum number of
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* messages that may be placed in the message queue.
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* pmsgq - This parameter is a address of a pointer
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*
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* Returned Value:
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* Zero (OK) is returned on success. Otherwise, a negated errno value is
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* returned to indicate the nature of the failure.
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*
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* EINVAL attr is NULL or either attr->mq_mqssize or attr->mq_maxmsg
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* have an invalid value
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* ENOSPC There is insufficient space for the creation of the new
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* message queue
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*
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****************************************************************************/
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int nxmq_alloc_msgq(FAR struct mq_attr *attr,
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FAR struct mqueue_inode_s **pmsgq);
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/****************************************************************************
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* Name: file_mq_open
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*
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* Description:
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* This function establish a connection between a named message queue and
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* the calling task. This is an internal OS interface. It is functionally
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* equivalent to mq_open() except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_open() for a more complete description of the
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* behavior of this function
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*
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* Input Parameters:
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* mq_name - Name of the queue to open
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* oflags - open flags
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* Optional parameters. When the O_CREAT flag is specified, two optional
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* parameters are expected:
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*
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* 1. mode_t mode, and
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* 2. struct mq_attr *attr. The mq_maxmsg attribute
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* is used at the time that the message queue is
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* created to determine the maximum number of
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* messages that may be placed in the message queue.
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* NOT NULL Message queue descriptor, NULL failed.
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*
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****************************************************************************/
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int file_mq_open(FAR struct file *mq,
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FAR const char *mq_name, int oflags, ...);
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/****************************************************************************
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* Name: file_mq_close
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*
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* Description:
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* This is an internal OS interface. It is functionally equivalent to
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* mq_close() except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_close() for a more complete description of the
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* behavior of this function
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*
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* Input Parameters:
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* mq - Message queue descriptor.
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*
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* Returned Value:
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* This is an internal OS interface and should not be used by applications.
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* It follows the NuttX internal error return policy: Zero (OK) is
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* returned on success. A negated errno value is returned on failure.
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*
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****************************************************************************/
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int file_mq_close(FAR struct file *mq);
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/****************************************************************************
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* Name: file_mq_unlink
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*
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* Description:
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* This is an internal OS interface. It is functionally equivalent to
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* mq_unlink() except that:
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*
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* - It is not a cancellation point, and
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* - It does not modify the errno value.
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*
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* See comments with mq_unlink() for a more complete description of the
|
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* behavior of this function
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*
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* Input Parameters:
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* mq_name - Name of the message queue
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*
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* Returned Value:
|
|
* This is an internal OS interface and should not be used by applications.
|
|
* It follows the NuttX internal error return policy: Zero (OK) is
|
|
* returned on success. A negated errno value is returned on failure.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int file_mq_unlink(FAR const char *mq_name);
|
|
|
|
/****************************************************************************
|
|
* Name: file_mq_send
|
|
*
|
|
* Description:
|
|
* This function adds the specified message (msg) to the message queue
|
|
* (mq). This is an internal OS interface. It is functionally
|
|
* equivalent to mq_send() except that:
|
|
*
|
|
* - It is not a cancellation point, and
|
|
* - It does not modify the errno value.
|
|
*
|
|
* See comments with mq_send() for a more complete description of the
|
|
* behavior of this function
|
|
*
|
|
* Input Parameters:
|
|
* mq - Message queue descriptor
|
|
* msg - Message to send
|
|
* msglen - The length of the message in bytes
|
|
* prio - The priority of the message
|
|
*
|
|
* Returned Value:
|
|
* This is an internal OS interface and should not be used by applications.
|
|
* It follows the NuttX internal error return policy: Zero (OK) is
|
|
* returned on success. A negated errno value is returned on failure.
|
|
* (see mq_send() for the list list valid return values).
|
|
*
|
|
****************************************************************************/
|
|
|
|
int file_mq_send(FAR struct file *mq, FAR const char *msg, size_t msglen,
|
|
unsigned int prio);
|
|
|
|
/****************************************************************************
|
|
* Name: file_mq_timedsend
|
|
*
|
|
* Description:
|
|
* This function adds the specified message (msg) to the message queue
|
|
* (mq). file_mq_timedsend() behaves just like mq_send(), except that if
|
|
* the queue is full and the O_NONBLOCK flag is not enabled for the
|
|
* message queue description, then abstime points to a structure which
|
|
* specifies a ceiling on the time for which the call will block.
|
|
*
|
|
* file_mq_timedsend() is functionally equivalent to mq_timedsend() except
|
|
* that:
|
|
*
|
|
* - It is not a cancellation point, and
|
|
* - It does not modify the errno value.
|
|
*
|
|
* See comments with mq_timedsend() for a more complete description of the
|
|
* behavior of this function
|
|
*
|
|
* Input Parameters:
|
|
* mq - Message queue descriptor
|
|
* msg - Message to send
|
|
* msglen - The length of the message in bytes
|
|
* prio - The priority of the message
|
|
* abstime - the absolute time to wait until a timeout is decleared
|
|
*
|
|
* Returned Value:
|
|
* This is an internal OS interface and should not be used by applications.
|
|
* It follows the NuttX internal error return policy: Zero (OK) is
|
|
* returned on success. A negated errno value is returned on failure.
|
|
* (see mq_timedsend() for the list list valid return values).
|
|
*
|
|
* EAGAIN The queue was empty, and the O_NONBLOCK flag was set for the
|
|
* message queue description referred to by mq.
|
|
* EINVAL Either msg or mq is NULL or the value of prio is invalid.
|
|
* EPERM Message queue opened not opened for writing.
|
|
* EMSGSIZE 'msglen' was greater than the maxmsgsize attribute of the
|
|
* message queue.
|
|
* EINTR The call was interrupted by a signal handler.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int file_mq_timedsend(FAR struct file *mq, FAR const char *msg,
|
|
size_t msglen, unsigned int prio,
|
|
FAR const struct timespec *abstime);
|
|
|
|
/****************************************************************************
|
|
* Name: file_mq_receive
|
|
*
|
|
* Description:
|
|
* This function receives the oldest of the highest priority messages
|
|
* from the message queue specified by "mq." This is an internal OS
|
|
* interface. It is functionally equivalent to mq_receive except that:
|
|
*
|
|
* - It is not a cancellation point, and
|
|
* - It does not modify the errno value.
|
|
*
|
|
* See comments with mq_receive() for a more complete description of the
|
|
* behavior of this function
|
|
*
|
|
* Input Parameters:
|
|
* mq - Message Queue Descriptor
|
|
* msg - Buffer to receive the message
|
|
* msglen - Size of the buffer in bytes
|
|
* prio - If not NULL, the location to store message priority.
|
|
*
|
|
* Returned Value:
|
|
* This is an internal OS interface and should not be used by applications.
|
|
* It follows the NuttX internal error return policy: Zero (OK) is
|
|
* returned on success. A negated errno value is returned on failure.
|
|
* (see mq_receive() for the list list valid return values).
|
|
*
|
|
****************************************************************************/
|
|
|
|
ssize_t file_mq_receive(FAR struct file *mq, FAR char *msg, size_t msglen,
|
|
FAR unsigned int *prio);
|
|
|
|
/****************************************************************************
|
|
* Name: file_mq_timedreceive
|
|
*
|
|
* Description:
|
|
* This function receives the oldest of the highest priority messages from
|
|
* the message queue specified by "mq." If the message queue is empty
|
|
* and O_NONBLOCK was not set, file_mq_timedreceive() will block until a
|
|
* message is added to the message queue (or until a timeout occurs).
|
|
*
|
|
* file_mq_timedreceive() is an internal OS interface. It is functionally
|
|
* equivalent to mq_timedreceive() except that:
|
|
*
|
|
* - It is not a cancellation point, and
|
|
* - It does not modify the errno value.
|
|
*
|
|
* See comments with mq_timedreceive() for a more complete description of
|
|
* the behavior of this function
|
|
*
|
|
* Input Parameters:
|
|
* mq - Message Queue Descriptor
|
|
* msg - Buffer to receive the message
|
|
* msglen - Size of the buffer in bytes
|
|
* prio - If not NULL, the location to store message priority.
|
|
* abstime - the absolute time to wait until a timeout is declared.
|
|
*
|
|
* Returned Value:
|
|
* This is an internal OS interface and should not be used by applications.
|
|
* It follows the NuttX internal error return policy: Zero (OK) is
|
|
* returned on success. A negated errno value is returned on failure.
|
|
* (see mq_timedreceive() for the list list valid return values).
|
|
*
|
|
****************************************************************************/
|
|
|
|
ssize_t file_mq_timedreceive(FAR struct file *mq, FAR char *msg,
|
|
size_t msglen, FAR unsigned int *prio,
|
|
FAR const struct timespec *abstime);
|
|
|
|
/****************************************************************************
|
|
* Name: file_mq_setattr
|
|
*
|
|
* Description:
|
|
* This function sets the attributes associated with the
|
|
* specified message queue "mq". Only the "O_NONBLOCK"
|
|
* bit of the "mq_flags" can be changed.
|
|
*
|
|
* If "oldstat" is non-null, mq_setattr() will store the
|
|
* previous message queue attributes at that location (just
|
|
* as would have been returned by file_mq_getattr()).
|
|
*
|
|
* Input Parameters:
|
|
* mqdes - Message queue descriptor
|
|
* mq_stat - New attributes
|
|
* oldstate - Old attributes
|
|
*
|
|
* Returned Value:
|
|
* This is an internal OS interface and should not be used by applications.
|
|
* It follows the NuttX internal error return policy: Zero (OK) is
|
|
* returned on success. A negated errno value is returned on failure.
|
|
*
|
|
* Assumptions:
|
|
*
|
|
****************************************************************************/
|
|
|
|
int file_mq_setattr(FAR struct file *mq, FAR const struct mq_attr *mq_stat,
|
|
FAR struct mq_attr *oldstat);
|
|
|
|
/****************************************************************************
|
|
* Name: file_mq_getattr
|
|
*
|
|
* Description:
|
|
* This functions gets status information and attributes
|
|
* associated with the specified message queue.
|
|
*
|
|
* Input Parameters:
|
|
* mq - Message queue descriptor
|
|
* mq_stat - Buffer in which to return attributes
|
|
*
|
|
* Returned Value:
|
|
* This is an internal OS interface and should not be used by applications.
|
|
* It follows the NuttX internal error return policy: Zero (OK) is
|
|
* returned on success. A negated errno value is returned on failure.
|
|
*
|
|
* Assumptions:
|
|
*
|
|
****************************************************************************/
|
|
|
|
int file_mq_getattr(FAR struct file *mq, FAR struct mq_attr *mq_stat);
|
|
|
|
#undef EXTERN
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* CONFIG_MQ_MAXMSGSIZE > 0 */
|
|
#endif /* ___INCLUDE_NUTTX_MQUEUE_H */
|