libkern/libkern/c++/OSCollection.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /* IOCollection.h created by gvdl on Thu 1998-10-22 */
  23
  24 #ifndef _OS_OSCOLLECTION_H
  25 #define _OS_OSCOLLECTION_H
  26
  27 #include <libkern/c++/OSObject.h>
  28
  29 class OSDictionary;
  30
  31 /*!
  32     @class OSCollection
  33     @abstract Abstract super class for all collections.
  34     @discussion
  35     OSCollection is the abstract super class for all OSObject derived collections and provides the necessary interfaces for managing storage space and iteration through a collection.
  36 */
  37 class OSCollection : public OSObject
  38 {
  39     friend class OSCollectionIterator;
  40
  41     OSDeclareAbstractStructors(OSCollection);
  42
  43     struct ExpansionData { };
  44
  45 protected:
  46     unsigned int updateStamp;
  47
  48 private:
  49     /* Reserved for future use.  (Internal use only)  */
  50     // ExpansionData *reserved;
  51     unsigned int fOptions;
  52
  53 protected:
  54     // Member functions used by the OSCollectionIterator class.
  55     /*
  56         @function iteratorSize
  57         @abstract A pure virtual member function to return the size of the iterator context.
  58         @result Returns an integer size for the storage space required to contain context necessary for iterating through a collection.
  59         @discussion
  60         This member function is called by an OSCollectionIterator object to allow it to allocate enough storage space for the iterator context.  This context contains the data necessary to iterate through the collection when getNextObjectForIterator() is called.
  61     */
  62     virtual unsigned int iteratorSize() const = 0;
  63     /*
  64         @function initIterator
  65         @abstract Pure virtual member function to allocate and initialize the iterator context data.
  66         @param iterator The iterator context.
  67         @result Returns true if initialization was successful, false otherwise.
  68     */
  69     virtual bool initIterator(void *iterator) const = 0;
  70     /*
  71         @function getNextObjectForIterator
  72         @abstract A pure virtual member function which returns the next member of a collection.
  73         @param iterator The iterator context.
  74         @param ret The object returned to the caller.
  75         @result Returns true if an object was found, false otherwise.
  76         @discussion
  77         This is the entry point used by an OSCollectionIterator object to advance to next object in the collection.  The iterator context is passed to the receiver to allow it to find the location of the current object and then advance the iterator context to the next object.
  78     */
  79     virtual bool getNextObjectForIterator(void *iterator, OSObject **ret) const = 0;
  80
  81     /*
  82         @function init
  83         @abstract A member function to initialize the OSCollection object.
  84         @result Returns true if an object was initialized successfully, false otherwise.
  85         @discussion
  86         This function is used to initialize state within a newly created OSCollection object.
  87     */
  88     virtual bool init();
  89
  90 public:
  91     enum {
  92         kImmutable = 0x00000001,
  93         kMASK      = (unsigned) -1
  94     };
  95
  96     /*
  97         @function haveUpdated
  98         @abstract A member function to track of all updates to the collection.
  99     */
 100     void haveUpdated();
 101
 102     /*
 103         @function getCount
 104         @abstract A pure virtual member function which returns the number of objects in the collection subclass.
 105         @results Returns the number objects in a collection.
 106      */
 107     virtual unsigned int getCount() const = 0;
 108     /*
 109         @function getCapacity
 110         @abstract A pure virtual member function which returns the storage space in the collection subclass.
 111         @results Returns the number objects in a collection.
 112      */
 113     virtual unsigned int getCapacity() const = 0;
 114     /*
 115         @function getCapacityIncrement
 116         @abstract A pure virtual member function which returns the growth factor of the collection subclass.
 117         @results Returns the size by which the collection subclass should grow.
 118      */
 119     virtual unsigned int getCapacityIncrement() const = 0;
 120     /*
 121         @function setCapacityIncrement
 122         @abstract A pure virtual member function which sets the growth factor of the collection subclass.
 123         @param increment The new size by which the capacity of the collection should grow.
 124         @results Returns the new capacity increment.
 125      */
 126     virtual unsigned int setCapacityIncrement(unsigned increment) = 0;
 127
 128     /*
 129         @function ensureCapacity
 130         @abstract A pure virtual member function which
 131         @param newCapacity
 132         @result
 133      */
 134     virtual unsigned int ensureCapacity(unsigned int newCapacity) = 0;
 135
 136     /*
 137         @function flushCollection
 138         @abstract A pure virtual member function which
 139      */
 140     virtual void flushCollection() = 0;
 141
 142     /*!
 143         @function setOptions
 144         @abstract This function is used to recursively set option bits in this collection and all child collections.
 145         @discussion setOptions is a recursive function but the OSCollection class itself does not know the structure of the particular collection.  This means that all derived classes are expected to override this method and recurse if the old value of the option was NOT set, which is why the old value is returned.  As this function is a reserved function override it is very multi purpose.  It can be used to get & set the options,
 146         @param options Set the (options & mask) bits.
 147         @param mask The mask of bits which need to be set, 0 to get the current value.
 148         @result The options before the set operation, NB setOptions(?,0) returns the current value of this collection.
 149      */
 150     OSMetaClassDeclareReservedUsed(OSCollection, 0);
 151     virtual unsigned setOptions(unsigned options, unsigned mask, void * = 0);
 152
 153     /*!
 154         @function copyCollection
 155         @abstract Do a deep copy of a collection tree.
 156         @discussion This function copies this collection and all of the contained collections recursively.  Objects that don't derive from OSContainter are NOT copied, that is objects like OSString and OSData.  To a derive from OSConnection::copyCollection some code is required to be implemented in the derived class, below is the skeleton pseudo code to copy a collection.
 157
 158 OSCollection * <MyCollection>::copyCollection(OSDictionary *inCycleDict)
 159 {
 160     bool allocDict = !cycleDict;
 161     OSCollection *ret = 0;
 162     <MyCollection> *newMyColl = 0;
 163
 164     if (allocDict)
 165         cycleDict = OSDictionary::withCapacity(16);
 166     if (!cycleDict)
 167         return 0;
 168
 169     do {
 170         // Check to see if we already have a copy of the new dictionary
 171         ret = super::copyCollection(cycleDict);
 172         if (ret)
 173             continue;
 174
 175         // Your code goes here to copy your collection,
 176         // see OSArray & OSDictionary for examples.
 177         newMyColl = <MyCollection>::with<MyCollection>(this);
 178         if (!newMyColl)
 179             continue;
 180
 181         // Insert object into cycle Dictionary
 182         cycleDict->setObject((const OSSymbol *) this, newMyColl);
 183
 184         // Duplicate any collections in us
 185         for (unsigned int i = 0; i < count; i++) {
 186             OSObject *obj = getObject(i);
 187             OSCollection *coll = OSDynamicCast(OSCollection, obj);
 188
 189             if (coll) {
 190                 OSCollection *newColl = coll->copyCollection(cycleDict);
 191                 if (!newColl)
 192                     goto abortCopy;
 193
 194                 newMyColl->replaceObject(i, newColl);
 195                 newColl->release();
 196             };
 197         };
 198
 199         ret = newMyColl;
 200         newMyColl = 0;
 201
 202     } while (false);
 203
 204 abortCopy:
 205     if (newMyColl)
 206         newMyColl->release();
 207
 208     if (allocDict)
 209         cycleDict->release();
 210
 211     return ret;
 212 }
 213
 214         @param cycleDict Is a dictionary of all of the collections that have been, to start the copy at the top level just leave this field 0.
 215         @result The newly copied collecton or 0 if insufficient memory
 216     */
 217     virtual OSCollection *copyCollection(OSDictionary *cycleDict = 0);
 218     OSMetaClassDeclareReservedUsed(OSCollection, 1);
 219
 220     OSMetaClassDeclareReservedUnused(OSCollection, 2);
 221     OSMetaClassDeclareReservedUnused(OSCollection, 3);
 222     OSMetaClassDeclareReservedUnused(OSCollection, 4);
 223     OSMetaClassDeclareReservedUnused(OSCollection, 5);
 224     OSMetaClassDeclareReservedUnused(OSCollection, 6);
 225     OSMetaClassDeclareReservedUnused(OSCollection, 7);
 226 };
 227
 228 #endif /* !_OS_OSCOLLECTION_H */