px4-firmware/apps/controllib/block/UOrbPublication.hpp

119 lines
3.6 KiB
C++

/****************************************************************************
*
* Copyright (C) 2012 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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****************************************************************************/
/**
* @file UOrbPublication.h
*
*/
#pragma once
#include <uORB/uORB.h>
#include "Block.hpp"
#include "List.hpp"
namespace control
{
class Block;
/**
* Base publication warapper class, used in list traversal
* of various publications.
*/
class __EXPORT UOrbPublicationBase : public ListNode<control::UOrbPublicationBase *>
{
public:
UOrbPublicationBase(
List<UOrbPublicationBase *> * list,
const struct orb_metadata *meta) :
_meta(meta),
_handle() {
if (list != NULL) list->add(this);
}
void update() {
orb_publish(getMeta(), getHandle(), getDataVoidPtr());
}
virtual void *getDataVoidPtr() = 0;
virtual ~UOrbPublicationBase() {
orb_unsubscribe(getHandle());
}
const struct orb_metadata *getMeta() { return _meta; }
int getHandle() { return _handle; }
protected:
void setHandle(orb_advert_t handle) { _handle = handle; }
const struct orb_metadata *_meta;
orb_advert_t _handle;
};
/**
* UOrb Publication wrapper class
*/
template<class T>
class UOrbPublication :
public T, // this must be first!
public UOrbPublicationBase
{
public:
/**
* Constructor
*
* @param list A list interface for adding to list during construction
* @param meta The uORB metadata (usually from the ORB_ID() macro)
* for the topic.
*/
UOrbPublication(
List<UOrbPublicationBase *> * list,
const struct orb_metadata *meta) :
T(), // initialize data structure to zero
UOrbPublicationBase(list, meta) {
// It is important that we call T()
// before we publish the data, so we
// call this here instead of the base class
setHandle(orb_advertise(getMeta(), getDataVoidPtr()));
}
virtual ~UOrbPublication() {}
/*
* XXX
* This function gets the T struct, assuming
* the struct is the first base class, this
* should use dynamic cast, but doesn't
* seem to be available
*/
void *getDataVoidPtr() { return (void *)(T *)(this); }
};
} // namespace control