xnu-792.18.15.tar.gz

[apple/xnu.git] / iokit / IOKit / pwr_mgt / IOPMinformeeList.h

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 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
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 * as defined in and that are subject to the Apple Public Source License
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 * 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,
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 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
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#include <libkern/c++/OSObject.h>
#include <IOKit/IOLocks.h>
#include <IOKit/IOReturn.h>

class IOPMinformee;
class IOService;

class IOPMinformeeList : public OSObject
{
OSDeclareDefaultStructors(IOPMinformeeList)

private:
    IOPMinformee       *firstItem;      // pointer to first informee in the list
    unsigned long       length;         // how many informees are in the list

public:
    void initialize ( void );
    void free ( void );

    unsigned long numberOfItems ( void );

    IOReturn addToList ( IOPMinformee *   newInformee );
    IOReturn removeFromList ( IOService * theItem );
    
    IOPMinformee * firstInList ( void );
    IOPMinformee * nextInList ( IOPMinformee * currentItem );
    
    IOPMinformee * findItem ( IOService * driverOrChild );        

    // This lock must be held while modifying list or length
    static IORecursiveLock * getSharedRecursiveLock( void );
};