/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This 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 OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_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 IOCommandPool; /*! * @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 { OSDeclareAbstractStructors(IOCommand) protected: virtual bool init(void); public: /*! @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_ */