/*
* Copyright (c) 2019 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
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*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
*
* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
*
* HISTORY
*
* 2001-01-18 gvdl Made the primary queue pointer public, to be used when
* Ownership is clear.
* 11/13/2000 CJS Created IOCommand class and implementation
*
*/
/*!
* @header IOCommand
* @abstract
* This header contains the IOCommand class definition.
*/
#ifndef _IOKIT_IO_COMMAND_H_
#define _IOKIT_IO_COMMAND_H_
/*
* Kernel
*/
#if defined(KERNEL) && defined(__cplusplus)
#include <kern/queue.h>
#include <libkern/c++/OSObject.h>
/*!
* @class IOCommand
* @abstract
* This class is an abstract class which represents an I/O command.
* @discussion
* This class is an abstract class which represents an I/O command passed
* from a device driver to a controller. All controller commands (e.g. IOATACommand)
* should inherit from this class.
*/
class IOCommand : public OSObject
{
OSDeclareDefaultStructors(IOCommand);
public:
virtual bool init(void) APPLE_KEXT_OVERRIDE;
/*! @var fCommandChain
* This variable is used by the current 'owner' to queue the command. During the life cycle of a command it moves through a series of queues. This is the queue pointer for it. Only valid while 'ownership' is clear. For instance a IOCommandPool uses this pointer to maintain its list of free commands. May be manipulated using the kern/queue.h macros */
queue_chain_t fCommandChain; /* used to queue commands */
};
#endif /* defined(KERNEL) && defined(__cplusplus) */
#endif /* _IOKIT_IO_COMMAND_H_ */