Subversion Repositories openrisc_me

/* Copyright 2002, Red Hat Inc. */

#include <mqueue.h>

#include <fcntl.h>

#include <errno.h>

#include <sys/ipc.h>

#include <sys/sem.h>

#include <string.h>

#include <stdlib.h>

#define _LIBC 1

#include <sys/lock.h>

#undef _LIBC

#include "mqlocal.h"

__LOCK_INIT(static, mq_wrbuf_lock);

int

mq_send (mqd_t msgid, const char *msg, size_t msg_len, unsigned int msg_prio)

{

  struct libc_mq *info;

  struct sembuf sb2 = {2, -1, 0};

  struct sembuf sb3 = {3, 1, 0};

  int rc;

  int ipcflag;

  info = __find_mq (msgid);

  if (info == NULL || (info->oflag & O_ACCMODE) == O_RDONLY)

    {

      errno = EBADF;

      return -1;

    }

  if (msg_len > info->attr->mq_msgsize)

    {

      errno = EMSGSIZE;

      return -1;

    }

  if (msg_prio > MQ_PRIO_MAX)

    {

      errno = EINVAL;

      return -1;

    }

  __lock_acquire (mq_wrbuf_lock);

  memcpy (info->wrbuf->text, msg, msg_len);

  info->wrbuf->type = (MQ_PRIO_MAX - msg_prio);

  ipcflag = (info->attr->mq_flags & O_NONBLOCK) ? IPC_NOWAIT : 0;

  sb2.sem_flg = ipcflag;

  /* check to see if max msgs are on queue */

  rc = semop (info->semid, &sb2, 1);

  if (rc == 0)

    rc = msgsnd (info->msgqid, info->wrbuf, msg_len, ipcflag);

  if (rc == 0)

    semop (info->semid, &sb3, 1);  /* increment number of reads */

  __lock_release (mq_wrbuf_lock);

  return rc;

}