Function pipe_fops_close

components/drivers/ipc/pipe.c:121–167

* @brief This function will close a pipe. * * @param fd is the file descriptor. * * @return Return the operation status. * When the return value is 0, it means the operation is successful. * When the return value is -1, it means the file descriptor is invalid. */

 *           When the return value is -1, it means the file descriptor is invalid.
 */
static int pipe_fops_close(struct dfs_file *fd)
{
    rt_device_t device;
    rt_pipe_t *pipe;

    pipe = (rt_pipe_t *)fd->vnode->data;
    if (!pipe)
    {
        return -1;
    }

    device = &pipe->parent;
    rt_mutex_take(&pipe->lock, RT_WAITING_FOREVER);

    if ((fd->flags & O_RDONLY) == O_RDONLY)
    {
        pipe->reader -= 1;
    }

    if ((fd->flags & O_WRONLY) == O_WRONLY)
    {
        pipe->writer -= 1;
        while (!rt_list_isempty(&pipe->reader_queue.waiting_list))
        {
            rt_wqueue_wakeup(&pipe->reader_queue, (void*)POLLIN);
        }
    }

    if (fd->vnode->ref_count == 1)
    {
        if (pipe->fifo != RT_NULL)
        {
            rt_ringbuffer_destroy(pipe->fifo);
        }
        pipe->fifo = RT_NULL;
    }

    rt_mutex_release(&pipe->lock);

    if (fd->vnode->ref_count == 1 && pipe->is_named == RT_FALSE)
    {
        /* delete the unamed pipe */
        rt_pipe_delete(device->parent.name);
    }

    return 0;
}

/**
 * @brief    This function will get the pipe space size depends on the command.