/* * Copyright (c) 2012 Apple Inc. All rights reserved. * * @APPLE_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. 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 * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* CFBinaryHeap.h Copyright (c) 1998-2012, Apple Inc. All rights reserved. */ /*! @header CFBinaryHeap CFBinaryHeap implements a container which stores values sorted using a binary search algorithm. CFBinaryHeaps can be useful as priority queues. */ #if !defined(__COREFOUNDATION_CFBINARYHEAP__) #define __COREFOUNDATION_CFBINARYHEAP__ 1 #include <CoreFoundation/CFBase.h> CF_IMPLICIT_BRIDGING_ENABLED CF_EXTERN_C_BEGIN typedef struct { CFIndex version; void * info; const void *(*retain)(const void *info); void (*release)(const void *info); CFStringRef (*copyDescription)(const void *info); } CFBinaryHeapCompareContext; /*! @typedef CFBinaryHeapCallBacks Structure containing the callbacks for values of a CFBinaryHeap. @field version The version number of the structure type being passed in as a parameter to the CFBinaryHeap creation functions. This structure is version 0. @field retain The callback used to add a retain for the binary heap on values as they are put into the binary heap. This callback returns the value to use as the value in the binary heap, which is usually the value parameter passed to this callback, but may be a different value if a different value should be added to the binary heap. The binary heap's allocator is passed as the first argument. @field release The callback used to remove a retain previously added for the binary heap from values as they are removed from the binary heap. The binary heap's allocator is passed as the first argument. @field copyDescription The callback used to create a descriptive string representation of each value in the binary heap. This is used by the CFCopyDescription() function. @field compare The callback used to compare values in the binary heap for equality in some operations. */ typedef struct { CFIndex version; const void *(*retain)(CFAllocatorRef allocator, const void *ptr); void (*release)(CFAllocatorRef allocator, const void *ptr); CFStringRef (*copyDescription)(const void *ptr); CFComparisonResult (*compare)(const void *ptr1, const void *ptr2, void *context); } CFBinaryHeapCallBacks; /*! @constant kCFStringBinaryHeapCallBacks Predefined CFBinaryHeapCallBacks structure containing a set of callbacks appropriate for use when the values in a CFBinaryHeap are all CFString types. */ CF_EXPORT const CFBinaryHeapCallBacks kCFStringBinaryHeapCallBacks; /*! @typedef CFBinaryHeapApplierFunction Type of the callback function used by the apply functions of CFBinaryHeap. @param value The current value from the binary heap. @param context The user-defined context parameter given to the apply function. */ typedef void (*CFBinaryHeapApplierFunction)(const void *val, void *context); /*! @typedef CFBinaryHeapRef This is the type of a reference to CFBinaryHeaps. */ typedef struct __CFBinaryHeap * CFBinaryHeapRef; /*! @function CFBinaryHeapGetTypeID Returns the type identifier of all CFBinaryHeap instances. */ CF_EXPORT CFTypeID CFBinaryHeapGetTypeID(void); /*! @function CFBinaryHeapCreate Creates a new mutable binary heap with the given values. @param allocator The CFAllocator which should be used to allocate memory for the binary heap and its storage for values. This parameter may be NULL in which case the current default CFAllocator is used. If this reference is not a valid CFAllocator, the behavior is undefined. @param capacity A hint about the number of values that will be held by the CFBinaryHeap. Pass 0 for no hint. The implementation may ignore this hint, or may use it to optimize various operations. A heap's actual capacity is only limited by address space and available memory constraints). If this parameter is negative, the behavior is undefined. @param callBacks A pointer to a CFBinaryHeapCallBacks structure initialized with the callbacks for the binary heap to use on each value in the binary heap. A copy of the contents of the callbacks structure is made, so that a pointer to a structure on the stack can be passed in, or can be reused for multiple binary heap creations. If the version field of this callbacks structure is not one of the defined ones for CFBinaryHeap, the behavior is undefined. The retain field may be NULL, in which case the CFBinaryHeap will do nothing to add a retain to values as they are put into the binary heap. The release field may be NULL, in which case the CFBinaryHeap will do nothing to remove the binary heap's retain (if any) on the values when the heap is destroyed or a key-value pair is removed. If the copyDescription field is NULL, the binary heap will create a simple description for a value. If the equal field is NULL, the binary heap will use pointer equality to test for equality of values. This callbacks parameter itself may be NULL, which is treated as if a valid structure of version 0 with all fields NULL had been passed in. Otherwise, if any of the fields are not valid pointers to functions of the correct type, or this parameter is not a valid pointer to a CFBinaryHeapCallBacks callbacks structure, the behavior is undefined. If any of the values put into the binary heap is not one understood by one of the callback functions the behavior when that callback function is used is undefined. @param compareContext A pointer to a CFBinaryHeapCompareContext structure. @result A reference to the new CFBinaryHeap. */ CF_EXPORT CFBinaryHeapRef CFBinaryHeapCreate(CFAllocatorRef allocator, CFIndex capacity, const CFBinaryHeapCallBacks *callBacks, const CFBinaryHeapCompareContext *compareContext); /*! @function CFBinaryHeapCreateCopy Creates a new mutable binary heap with the values from the given binary heap. @param allocator The CFAllocator which should be used to allocate memory for the binary heap and its storage for values. This parameter may be NULL in which case the current default CFAllocator is used. If this reference is not a valid CFAllocator, the behavior is undefined. @param capacity A hint about the number of values that will be held by the CFBinaryHeap. Pass 0 for no hint. The implementation may ignore this hint, or may use it to optimize various operations. A heap's actual capacity is only limited by address space and available memory constraints). This parameter must be greater than or equal to the count of the heap which is to be copied, or the behavior is undefined. If this parameter is negative, the behavior is undefined. @param heap The binary heap which is to be copied. The values from the binary heap are copied as pointers into the new binary heap (that is, the values themselves are copied, not that which the values point to, if anything). However, the values are also retained by the new binary heap. The count of the new binary will be the same as the given binary heap. The new binary heap uses the same callbacks as the binary heap to be copied. If this parameter is not a valid CFBinaryHeap, the behavior is undefined. @result A reference to the new mutable binary heap. */ CF_EXPORT CFBinaryHeapRef CFBinaryHeapCreateCopy(CFAllocatorRef allocator, CFIndex capacity, CFBinaryHeapRef heap); /*! @function CFBinaryHeapGetCount Returns the number of values currently in the binary heap. @param heap The binary heap to be queried. If this parameter is not a valid CFBinaryHeap, the behavior is undefined. @result The number of values in the binary heap. */ CF_EXPORT CFIndex CFBinaryHeapGetCount(CFBinaryHeapRef heap); /*! @function CFBinaryHeapGetCountOfValue Counts the number of times the given value occurs in the binary heap. @param heap The binary heap to be searched. If this parameter is not a valid CFBinaryHeap, the behavior is undefined. @param value The value for which to find matches in the binary heap. The compare() callback provided when the binary heap was created is used to compare. If the compare() callback was NULL, pointer equality (in C, ==) is used. If value, or any of the values in the binary heap, are not understood by the compare() callback, the behavior is undefined. @result The number of times the given value occurs in the binary heap. */ CF_EXPORT CFIndex CFBinaryHeapGetCountOfValue(CFBinaryHeapRef heap, const void *value); /*! @function CFBinaryHeapContainsValue Reports whether or not the value is in the binary heap. @param heap The binary heap to be searched. If this parameter is not a valid CFBinaryHeap, the behavior is undefined. @param value The value for which to find matches in the binary heap. The compare() callback provided when the binary heap was created is used to compare. If the compare() callback was NULL, pointer equality (in C, ==) is used. If value, or any of the values in the binary heap, are not understood by the compare() callback, the behavior is undefined. @result true, if the value is in the specified binary heap, otherwise false. */ CF_EXPORT Boolean CFBinaryHeapContainsValue(CFBinaryHeapRef heap, const void *value); /*! @function CFBinaryHeapGetMinimum Returns the minimum value is in the binary heap. If the heap contains several equal minimum values, any one may be returned. @param heap The binary heap to be searched. If this parameter is not a valid CFBinaryHeap, the behavior is undefined. @result A reference to the minimum value in the binary heap, or NULL if the binary heap contains no values. */ CF_EXPORT const void * CFBinaryHeapGetMinimum(CFBinaryHeapRef heap); /*! @function CFBinaryHeapGetMinimumIfPresent Returns the minimum value is in the binary heap, if present. If the heap contains several equal minimum values, any one may be returned. @param heap The binary heap to be searched. If this parameter is not a valid CFBinaryHeap, the behavior is undefined. @param value A C pointer to pointer-sized storage to be filled with the minimum value in the binary heap. If this value is not a valid C pointer to a pointer-sized block of storage, the result is undefined. If the result of the function is false, the value stored at this address is undefined. @result true, if a minimum value was found in the specified binary heap, otherwise false. */ CF_EXPORT Boolean CFBinaryHeapGetMinimumIfPresent(CFBinaryHeapRef heap, const void **value); /*! @function CFBinaryHeapGetValues Fills the buffer with values from the binary heap. @param heap The binary heap to be queried. If this parameter is not a valid CFBinaryHeap, the behavior is undefined. @param values A C array of pointer-sized values to be filled with values from the binary heap. The values in the C array are ordered from least to greatest. If this parameter is not a valid pointer to a C array of at least CFBinaryHeapGetCount() pointers, the behavior is undefined. */ CF_EXPORT void CFBinaryHeapGetValues(CFBinaryHeapRef heap, const void **values); /*! @function CFBinaryHeapApplyFunction Calls a function once for each value in the binary heap. @param heap The binary heap to be operated upon. If this parameter is not a valid CFBinaryHeap, the behavior is undefined. @param applier The callback function to call once for each value in the given binary heap. If this parameter is not a pointer to a function of the correct prototype, the behavior is undefined. If there are values in the binary heap which the applier function does not expect or cannot properly apply to, the behavior is undefined. @param context A pointer-sized user-defined value, which is passed as the second parameter to the applier function, but is otherwise unused by this function. If the context is not what is expected by the applier function, the behavior is undefined. */ CF_EXPORT void CFBinaryHeapApplyFunction(CFBinaryHeapRef heap, CFBinaryHeapApplierFunction applier, void *context); /*! @function CFBinaryHeapAddValue Adds the value to the binary heap. @param heap The binary heap to which the value is to be added. If this parameter is not a valid mutable CFBinaryHeap, the behavior is undefined. @param value The value to add to the binary heap. The value is retained by the binary heap using the retain callback provided when the binary heap was created. If the value is not of the sort expected by the retain callback, the behavior is undefined. */ CF_EXPORT void CFBinaryHeapAddValue(CFBinaryHeapRef heap, const void *value); /*! @function CFBinaryHeapRemoveMinimumValue Removes the minimum value from the binary heap. @param heap The binary heap from which the minimum value is to be removed. If this parameter is not a valid mutable CFBinaryHeap, the behavior is undefined. */ CF_EXPORT void CFBinaryHeapRemoveMinimumValue(CFBinaryHeapRef heap); /*! @function CFBinaryHeapRemoveAllValues Removes all the values from the binary heap, making it empty. @param heap The binary heap from which all of the values are to be removed. If this parameter is not a valid mutable CFBinaryHeap, the behavior is undefined. */ CF_EXPORT void CFBinaryHeapRemoveAllValues(CFBinaryHeapRef heap); CF_EXTERN_C_END CF_IMPLICIT_BRIDGING_DISABLED #endif /* ! __COREFOUNDATION_CFBINARYHEAP__ */