Function pipe

components/drivers/ipc/pipe.c:737–778

* @brief This function will creat a anonymous pipe. * * @param fildes[0] is the read handle. * fildes[1] is the write handle. * * @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 operation is failed. */

 *           When the return value is -1, it means the operation is failed.
 */
int pipe(int fildes[2])
{
    rt_pipe_t *pipe;
    char dname[8];
    char dev_name[32];
    int pipeno = 0;

    pipeno = resource_id_get(&id_mgr);
    if (pipeno == -1)
    {
        return -1;
    }
    rt_snprintf(dname, sizeof(dname), "pipe%d", pipeno);

    pipe = rt_pipe_create(dname, RT_USING_POSIX_PIPE_SIZE);
    if (pipe == RT_NULL)
    {
        resource_id_put(&id_mgr, pipeno);
        return -1;
    }

    pipe->is_named = RT_FALSE; /* unamed pipe */
    pipe->pipeno = pipeno;
    rt_snprintf(dev_name, sizeof(dev_name), "/dev/%s", dname);

    fildes[1] = open(dev_name, O_WRONLY, 0);
    if (fildes[1] < 0)
    {
        rt_pipe_delete(dname);
        return -1;
    }

    fildes[0] = open(dev_name, O_RDONLY, 0);
    if (fildes[0] < 0)
    {
        close(fildes[1]);
        rt_pipe_delete(dname);
        return -1;
    }

    return 0;
}

/**
 * @brief    This function will create a named pipe.