| /**************************************************************************** |
| * sched/mqueue/msgctl.c |
| * |
| * 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 "mqueue/msg.h" |
| |
| /**************************************************************************** |
| * Public Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Name: msgctl |
| * |
| * Description: |
| * System V message control operations. |
| * msgctl() performs the control operation specified by cmd on the |
| * System V message queue with identifier msqid. |
| * |
| * Input Parameters: |
| * msqid - System V message queue identifier |
| * cmd - Command operations |
| * msqid_ds - Defines a message queue |
| * |
| * Returned Value: |
| * On success, IPC_STAT, IPC_SET, and IPC_RMID return 0. A |
| * successful IPC_INFO or MSG_INFO operation returns the index of |
| * the highest used entry in the kernel's internal array recording |
| * information about all message queues. (This information can be |
| * used with repeated MSG_STAT or MSG_STAT_ANY operations to obtain |
| * information about all queues on the system.) A successful |
| * MSG_STAT or MSG_STAT_ANY operation returns the identifier of the |
| * queue whose index was given in msqid. |
| * |
| * On failure, -1 is returned and errno is set to indicate the error. |
| * |
| ****************************************************************************/ |
| |
| int msgctl(int msqid, int cmd, FAR struct msqid_ds *buf) |
| { |
| FAR struct msgq_s *msgq; |
| irqstate_t flags; |
| int ret = OK; |
| |
| flags = enter_critical_section(); |
| |
| msgq = nxmsg_lookup(msqid); |
| if (msgq == NULL) |
| { |
| ret = -EINVAL; |
| goto errout_with_critical; |
| } |
| |
| switch (cmd) |
| { |
| case IPC_RMID: |
| { |
| nxmsg_free(msgq); |
| break; |
| } |
| |
| case IPC_SET: |
| { |
| if (buf == NULL) |
| { |
| ret = -EFAULT; |
| break; |
| } |
| |
| msgq->maxmsgs = buf->msg_qbytes / CONFIG_MQ_MAXMSGSIZE; |
| |
| break; |
| } |
| |
| case IPC_STAT: |
| { |
| if (buf == NULL) |
| { |
| ret = -EFAULT; |
| break; |
| } |
| |
| buf->msg_qnum = list_length(&msgq->msglist); |
| buf->msg_cbytes = buf->msg_qnum * CONFIG_MQ_MAXMSGSIZE; |
| buf->msg_qbytes = msgq->maxmsgs * CONFIG_MQ_MAXMSGSIZE; |
| break; |
| } |
| |
| default: |
| { |
| ret = -EINVAL; |
| break; |
| } |
| } |
| |
| errout_with_critical: |
| leave_critical_section(flags); |
| if (ret < 0) |
| { |
| set_errno(-ret); |
| return ERROR; |
| } |
| |
| return ret; |
| } |