[apple/xnu.git] / libkern / libkern / c++ / OSArray.h

/*
 * Copyright (c) 2000 Apple Computer, 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.
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 */
/* IOArray.h created by rsulack on Thu 11-Sep-1997 */
/* IOArray.h converted to C++ by gvdl on Fri 1998-10-30 */

#ifndef _OS_OSARRAY_H
#define _OS_OSARRAY_H

#include <libkern/c++/OSCollection.h>

class OSSerialize;

/*!
 * @header
 *
 * @abstract
 * This header declares the OSArray collection class.
 */
 
 
/*!
 * @class OSArray
 *
 * @abstract
 * OSArray provides an indexed store of objects.
 *
 * @discussion
 * OSArray is a container for Libkern C++ objects
 * (those derived from
 * @link //apple_ref/doc/class/OSMetaClassBase OSMetaClassBase@/link,
 * in particular
 * @link //apple_ref/doc/class/OSObject OSObject@/link).
 * Storage and access are by array index.
 *
 * You must generally cast retrieved objects from
 * @link //apple_ref/cpp/cl/OSObject OSObject@/link
 * to the desired class using
 * <code>@link //apple_ref/cpp/macro/OSDynamicCast OSDynamicCast@/link</code>.
 * This macro returns the object cast to the desired class,
 * or <code>NULL</code> if the object isn't derived from that class.
 *
 * As with all Libkern collection classes,
 * OSArray retains objects added to it,
 * and releases objects removed from it (or replaced).
 * An OSArray also grows as necessary to accommodate new objects,
 * <i>unlike</i> Core Foundation collections (it does not, however, shrink).
 *
 * <b>Use Restrictions</b>
 *
 * With very few exceptions in the I/O Kit, all Libkern-based C++
 * classes, functions, and macros are <b>unsafe</b>
 * to use in a primary interrupt context.
 * Consult the I/O Kit documentation related to primary interrupts 
 * for more information.
 *
 * OSArray provides no concurrency protection;
 * it's up to the usage context to provide any protection necessary.
 * Some portions of the I/O Kit, such as
 * @link //apple_ref/doc/class/IORegistryEntry IORegistryEntry@/link,
 * handle synchronization via defined member functions for setting
 * properties.
 */
class OSArray : public OSCollection
{
    friend class OSSet;
    friend class OSSerialize;

    OSDeclareDefaultStructors(OSArray)

protected:
    const OSMetaClassBase ** array;
    unsigned int             count;
    unsigned int             capacity;
    unsigned int             capacityIncrement;

    struct ExpansionData { };
    
   /* Reserved for future use. (Internal use only) */
    ExpansionData          * reserved;

   /* OSCollectionIterator interfaces. */
    virtual unsigned int iteratorSize() const;
    virtual bool initIterator(void * iterator) const;
    virtual bool getNextObjectForIterator(void * iterator, OSObject ** ret) const;

public:

   /*!
    * @function withCapacity
    *
    * @abstract
    * Creates and initializes an empty OSArray.
    * 
    * @param  capacity  The initial storage capacity of the array object.
    *
    * @result
    * An empty instance of OSArray with a retain count of 1;
    * <code>NULL</code> on failure.
    *
    * @discussion
    * <code>capacity</code> must be nonzero.
    * The new array will grow as needed to accommodate more objects
    * (<i>unlike</i> @link //apple_ref/doc/uid/20001502 CFMutableArray@/link,
    * for which the initial capacity is a hard limit).
    */
    static OSArray * withCapacity(unsigned int capacity);


   /*!
    * @function withObjects
    *
    * @abstract
    * Creates and initializes an OSArray populated with objects provided.
    *
    * @param objects   A C array of OSObject-derived instances.
    * @param count     The number of objects to be placed into the array.
    * @param capacity  The initial storage capacity of the array object.
    *                  If 0, <code>count</code> is used; otherwise this value
    *                  must be greater than or equal to <code>count</code>.
    *
    * @result
    * An instance of OSArray containing the objects provided,
    * with a retain count of 1;
    * <code>NULL</code> on failure.
    *
    * @discussion
    * <code>objects</code> must be non-<code>NULL</code>, and <code>count</code> must be nonzero.
    * If <code>capacity</code> is nonzero,
    * it must be greater than or equal to <code>count</code>.
    * The new array will grow as needed to accommodate more objects
    * (<i>unlike</i> @link //apple_ref/doc/uid/20001502 CFMutableArray@/link,
    * for which the initial capacity is a hard limit).
    */
    static OSArray * withObjects(
        const OSObject * objects[],
        unsigned int     count,
        unsigned int     capacity = 0);


   /*!
    * @function withArray
    *
    * @abstract
    * Creates and initializes an OSArray populated with the contents of another array.
    *
    * @param array     An OSArray whose contents will be stored
    *                  in the new instance.
    * @param capacity  The initial storage capacity of the array object.
    *                  If 0, the capacity is set to the number of objects
    *                  in <code>array</code>;
    *                  otherwise <code>capacity</code> must be
    *                  greater than or equal to the number of objects
    *                  in <code>array</code>.
    *
    * @result
    * An instance of OSArray containing the objects of <code>array</code>,
    * with a retain count of 1;
    * <code>NULL</code> on failure.
    *
    * @discussion
    * <code>array</code> must be non-<code>NULL</code>.
    * If <code>capacity</code> is nonzero,
    * it must be greater than or equal to <code>count</code>.
    * The new array will grow as needed to accommodate more objects
    * (<i>unlike</i> @link //apple_ref/doc/uid/20001502 CFMutableArray@/link,
    * for which the initial capacity is a hard limit).
    *
    * The objects in <code>array</code> are retained
    * for storage in the new OSArray,
    * not copied.
    */
    static OSArray * withArray(
        const OSArray * array,
        unsigned int    capacity = 0);


   /*!
    * @function initWithCapacity
    *
    * @abstract
    * Initializes a new instance of OSArray.
    *
    * @param capacity  The initial storage capacity of the array object.
    *
    * @result
    * <code>true</code> on success, <code>false</code> on failure.
    *
    * @discussion
    * Not for general use. Use the static instance creation method
    * <code>@link //apple_ref/cpp/clm/OSArray/withCapacity/staticOSArray*\/(unsignedint)
    * withCapacity@/link</code>
    * instead.
    *
    * <code>capacity</code> must be nonzero.
    * The new array will grow as needed to accommodate more objects
    * (<i>unlike</i> @link //apple_ref/doc/uid/20001502 CFMutableArray@/link,
    * for which the initial capacity is a hard limit).
    */
    virtual bool initWithCapacity(unsigned int capacity);


   /*!
    * @function initWithObjects
    *
    * @abstract
    * Initializes a new OSArray populated with objects provided.
    *
    * @param objects   A C array of OSObject-derived objects.
    * @param count     The number of objects to be placed into the array.
    * @param capacity  The initial storage capacity of the array object.
    *                  If 0, <code>count</code> is used; otherwise this value
    *                  must be greater than or equal to <code>count</code>.
    *
    * @result
    * <code>true</code> on success, <code>false</code> on failure.
    *
    * @discussion
    * Not for general use. Use the static instance creation method
    * <code>@link
    * //apple_ref/cpp/clm/OSArray/withObjects/staticOSArray*\/(constOSObject*,unsignedint,unsignedint)
    * withObjects@/link</code>
    * instead.
    *
    * <code>objects</code> must be non-<code>NULL</code>,
    * and <code>count</code> must be nonzero.
    * If <code>capacity</code> is nonzero,
    * it must be greater than or equal to <code>count</code>.
    * The new array will grow as needed to accommodate more objects
    * (<i>unlike</i> @link //apple_ref/doc/uid/20001502 CFMutableArray@/link,
    * for which the initial capacity is a hard limit).
    */
    virtual bool initWithObjects(
        const OSObject * objects[],
        unsigned int     count,
        unsigned int     capacity = 0);

   /*!
    * @function initWithArray
    *
    * @abstract
    * Initializes a new OSArray populated with the contents of another array.
    *
    * @param anArray  The array whose contents will be placed
    *                 in the new instance.
    * @param capacity The initial storage capacity of the array object.
    *                 If 0, the capacity is set to the number of objects
    *                 in <code>array</code>;
    *                 otherwise <code>capacity</code> must be
    *                 greater than or equal to the number of objects
    *                 in <code>array</code>.
    *
    * @result
    * <code>true</code> on success, <code>false</code> on failure.
    *
    * @discussion
    * Not for general use. Use the static instance creation method
    * <code>@link //apple_ref/cpp/clm/OSArray/withArray/staticOSArray*\/(constOSArray*,unsignedint)
    * withArray@/link</code> instead.
    *
    * <code>array</code> must be non-<code>NULL</code>.
    * If <code>capacity</code> is nonzero,
    * it must be greater than or equal to <code>count</code>.
    * The new array will grow as needed to accommodate more objects
    * (<i>unlike</i> @link //apple_ref/doc/uid/20001502 CFMutableArray@/link,
    * for which the initial capacity is a hard limit).
    *
    * The objects in <code>array</code> are retained for storage in the new OSArray,
    * not copied.
    */
    virtual bool initWithArray(
        const OSArray * anArray,
        unsigned int    capacity = 0);


   /*!
    * @function free
    *
    * @abstract
    * Deallocates or releases any resources
    * used by the OSArray instance.
    *
    * @discussion
    * This function should not be called directly;
    * use
    * <code>@link
    * //apple_ref/cpp/instm/OSObject/release/virtualvoid/()
    * release@/link</code>
    * instead.
    */
    virtual void free();


   /*!
    * @function getCount
    *
    * @abstract
    * Returns the current number of objects within the array.
    *
    * @result
    * The current number of objects within the array.
    */
    virtual unsigned int getCount() const;


   /*!
    * @function getCapacity
    *
    * @abstract
    * Returns the number of objects the array can store
    * without reallocating.
    *
    * @result
    * The number objects the array can store
    * without reallocating.
    *
    * @discussion
    * OSArray objects grow when full to accommodate additional objects.
    * See
    * <code>@link
    * //apple_ref/cpp/instm/OSArray/getCapacity/virtualunsignedint/()
    * getCapacityIncrement@/link</code>
    * and
    * @link
    * //apple_ref/cpp/instm/OSArray/ensureCapacity/virtualunsignedint/(unsignedint)
    * <code>ensureCapacity</code>.@/link
    */
    virtual unsigned int getCapacity() const;
    
    
   /*!
    * @function getCapacityIncrement
    *
    * @abstract
    * Returns the storage increment of the array.
    *
    * @result
    * The storage increment of the array.
    *
    * @discussion
    * An OSArray allocates storage for objects in multiples
    * of the capacity increment.
    */
    virtual unsigned int getCapacityIncrement() const;


   /*!
    * @function setCapacityIncrement
    *
    * @abstract
    * Sets the storage increment of the array.
    *
    * @result
    * The new storage increment of the array,
    * which may be different from the number requested.
    *
    * @discussion
    * An OSArray allocates storage for objects in multiples
    * of the capacity increment.
    * Calling this function does not immediately reallocate storage.
    */
    virtual unsigned int setCapacityIncrement(unsigned increment);


   /*!
    * @function ensureCapacity
    *
    * @abstract
    * Ensures the array has enough space
    * to store the requested number of objects.
    *
    * @param newCapacity  The total number of objects the array
    *                     should be able to store.
    *
    * @result
    * The new capacity of the array,
    * which may be different from the number requested
    * (if smaller, reallocation of storage failed).
    *
    * @discussion
    * This function immediately resizes the array, if necessary,
    * to accommodate at least <code>newCapacity</code> objects.
    * If <code>newCapacity</code> is not greater than the current capacity,
    * or if an allocation error occurs, the original capacity is returned.
    *
    * There is no way to reduce the capacity of an OSArray.
    */
    virtual unsigned int ensureCapacity(unsigned int newCapacity);


   /*!
    * @function flushCollection
    *
    * @abstract
    * Removes and releases all objects within the array.
    *
    * @discussion
    * The array's capacity (and therefore direct memory consumption)
    * is not reduced by this function.
    */
    virtual void flushCollection();


   /*!
    * @function setObject
    *
    * @abstract
    * Appends an object onto the end of the array,
    * increasing storage if necessary.
    *
    * @param anObject  The object to add to the OSArray instance.
    *
    * @result
    * <code>true</code> if the addition of <code>anObject</code> was successful,
    * <code>false</code> if not.
    *
    * @discussion
    * The array adds storage to accomodate the new object, if necessary.
    * If successfully added, the object is retained.
    */
    virtual bool setObject(const OSMetaClassBase * anObject);


   /*!
    * @function setObject
    *
    * @abstract
    * Inserts or appends an object into the array
    * at a particular index.
    *
    * @param index     The index in the array at which to insert the object.
    *                  Must be less than or equal to the array's count.
    * @param anObject  The object to add to the array.
    *
    * @result
    * <code>true</code> if the addition of <code>anObject</code>
    * was successful, <code>false</code> if not.
    *
    * @discussion
    * This function moves existing objects from <code>index</code> on,
    * in order to accommodate the new object;
    * it does not replace an existing object at <code>index</code>. See
    * <code>@link
    * //apple_ref/cpp/instm/OSArray/replaceObject/virtualvoid/(unsignedint,constOSMetaClassBase*)
    * replaceObject@/link</code>.
    * If successfully added, the object is retained.
    *
    * The array adds storage to accomodate the new object, if necessary.
    * Note, however, that this function does not allow for arbirtrary growth
    * of an array by specifying an index larger than the current count.
    * If you need to immediately grow an array by an arbitrary amount,
    * use
    * <code>@link
    * //apple_ref/cpp/instm/OSArray/ensureCapacity/virtualunsignedint/(unsignedint)
    * ensureCapacity@/link</code>.
    */
    virtual bool setObject(
        unsigned int            index,
        const OSMetaClassBase * anObject);


   /*!
    * @function merge
    *
    * @abstract
    * Appends the contents of an array onto the receiving array.
    *
    * @param  otherArray  The array whose contents will be appended
    *                     to the receiving array.
    * @result
    * <code>true</code> if merging was successful, <code>false</code> otherwise.
    *
    * @discussion
    * This function merely appends one array onto another.
    * Duplicates are not avoided and no sorting is performed.
    * Objects successfully added to the receiver are retained.
    */
    virtual bool merge(const OSArray * otherArray);


   /*!
    * @function replaceObject
    *
    * @abstract
    * Replaces an object in an array at a given index.
    *
    * @param index     The index of the object to be replaced.
    *                  Must be less than the array's count.
    * @param anObject  The object to be placed into the array.
    *
    * @discussion
    * The original object is released and the new object is retained.
    */
    virtual void replaceObject(
        unsigned int            index,
        const OSMetaClassBase * anObject);


   /*!
    * @function removeObject
    *
    * @abstract
    * Removes an object from the array.
    *
    * @param index  The index of the object to be removed.
    *
    * @discussion
    * This function moves existing objects to fill the vacated index
    * so that there are no gaps.
    * The object removed is released.
    */
    virtual void removeObject(unsigned int index);


   /*!
    * @function isEqualTo
    *
    * @abstract
    * Tests the equality of two OSArray objects.
    *
    * @param anArray  The array object being compared against the receiver.
    *
    * @result
    * <code>true</code> if the two arrays are equivalent,
    *<code>false</code> otherwise.
    *
    * @discussion
    * Two OSArray objects are considered equal if they have same count
    * and if the objects at corresponding indices compare as equal using
    * <code>@link
    * //apple_ref/cpp/instm/OSMetaClassBase/isEqualTo/virtualbool/(constOSMetaClassBase*)
    * isEqualTo@/link</code>.
    */
    virtual bool isEqualTo(const OSArray * anArray) const;


   /*!
    * @function isEqualTo
    *
    * @abstract
    * Tests the equality of an OSArray to an arbitrary object.
    *
    * @param anObject  The object to be compared against the receiver.
    *
    * @result
    * <code>true</code> if the two objects are equivalent,
    * <code>false</code> otherwise.
    *
    * @discussion
    * An OSArray is considered equal to another object
    * if that object is derived from OSArray
    * and contains the same or equivalent objects.
    */
    virtual bool isEqualTo(const OSMetaClassBase * anObject) const;


   /*!
    * @function getObject
    *
    * @abstract
    * Return the object stored at a given index.
    *
    * @param index The index of the object to be returned to caller.
    *
    * @result
    * The object stored at <code>index</code>,
    * or <code>NULL</code> if <code>index</code> lies past the end of the array.
    *
    * @discussion
    * The returned object will be released if removed from the array;
    * if you plan to store the reference, you should call
    * <code>@link
    * //apple_ref/cpp/instm/OSObject/retain/virtualvoid/()
    * retain@/link</code>
    * on that object.
    */
    virtual OSObject * getObject(unsigned int index) const;


   /*!
    * @function getLastObject
    *
    * @abstract
    * Returns the last object in the array.
    *
    * @result
    * The last object in the array,
    * or <code>NULL</code> if the array is empty.
    *
    * @discussion
    * The returned object will be released if removed from the array;
    * if you plan to store the reference, you should call
    * <code>@link
    * //apple_ref/cpp/instm/OSObject/retain/virtualvoid/()
    * retain@/link</code>
    * on that object.
    */
    virtual OSObject * getLastObject() const;


   /*!
    * @function getNextIndexOfObject
    *
    * @abstract
    * Scans the array for the next instance of a specific object
    * at or beyond a given index.
    *
    * @param anObject  The object to scan for.
    * @param index     The index at which to begin the scan.
    *
    * @result 
    * The next index of <code>anObject</code> in the array or (-1)
    * if none is found.
    *
    * @discussion
    * This function uses pointer equivalence, and does not use
    * <code>@link
    * //apple_ref/cpp/instm/OSMetaClassBase/isEqualTo/virtualbool/(constOSMetaClassBase*)
    * isEqualTo@/link</code>.
    */
    virtual unsigned int getNextIndexOfObject(
        const OSMetaClassBase * anObject,
        unsigned int            index) const;

   /*!
    * @function serialize
    *
    * @abstract
    * Archives the receiver into the provided
    * @link //apple_ref/doc/class/OSSerialize OSSerialize@/link object.
    *
    * @param serializer  The OSSerialize object.
    * @result
    * <code>true</code> if serialization succeeds, <code>false</code> if not.
    */
    virtual bool serialize(OSSerialize * serializer) const;


   /*!
    * @function setOptions
    *
    * @abstract
    * Recursively sets option bits in an array
    * and all child collections.
    *
    * @param options  A bitfield whose values turn the options on (1) or off (0).
    * @param mask     A mask indicating which bits
    *                 in <code>options</code> to change.
    *                 Pass 0 to get the whole current options bitfield
    *                 without changing any settings.
    * @param context  Unused.
    *
    * @result
    * The options bitfield as it was before the set operation.
    *
    * @discussion
    * Kernel extensions should not call this function.
    *
    * Child collections' options are changed only if the receiving array's
    * options actually change.
    */
    virtual unsigned setOptions(
        unsigned   options,
        unsigned   mask,
        void     * context = 0);


   /*!
    * @function copyCollection
    *
    * @abstract
    * Creates a deep copy of an array and its child collections.
    *
    * @param cycleDict  A dictionary of all of the collections
    *                   that have been copied so far,
    *                   which is used to track circular references.
    *                   To start the copy at the top level,
    *                   pass <code>NULL</code>.
    *
    * @result
    * The newly copied array, with a retain count of 1,
    * or <code>NULL</code> if there is insufficient memory to do the copy.
    *
    * @discussion
    * The receiving array, and any collections it contains,
    * recursively, are copied.
    * Objects that are not derived from OSCollection are retained
    * rather than copied.
    */
    OSCollection * copyCollection(OSDictionary * cycleDict = 0);

    OSMetaClassDeclareReservedUnused(OSArray, 0);
    OSMetaClassDeclareReservedUnused(OSArray, 1);
    OSMetaClassDeclareReservedUnused(OSArray, 2);
    OSMetaClassDeclareReservedUnused(OSArray, 3);
    OSMetaClassDeclareReservedUnused(OSArray, 4);
    OSMetaClassDeclareReservedUnused(OSArray, 5);
    OSMetaClassDeclareReservedUnused(OSArray, 6);
    OSMetaClassDeclareReservedUnused(OSArray, 7);
};

#endif /* !_OS_OSARRAY_H */