/**Interface for NSPointerFunctions for GNUStep
   Copyright (C) 2008 Free Software Foundation, Inc.

   Written by:  Richard Frith-Macdonald <rfm@gnu.org>
   Date:	2008
   
   This file is part of the GNUstep Base Library.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
   
   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.
   
   You should have received a copy of the GNU Lesser General Public
   License along with this library; if not, write to the Free
   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02111 USA.

   */ 

#ifndef __NSPointerFunctions_h_GNUSTEP_BASE_INCLUDE
#define __NSPointerFunctions_h_GNUSTEP_BASE_INCLUDE

#import	<Foundation/NSObject.h>

#if OS_API_VERSION(MAC_OS_X_VERSION_10_5, GS_API_LATEST)

#if	defined(__cplusplus)
extern "C" {
#endif

/** Options flags come in three groups  ...<br />
 *  Memory management options (only one of which may be set)<br />
 *  Personality options (only one of which may be set)<br />
 *  Others.
 */
enum {
  /** Garbage collected strong references , or retain counting if GC
   * is not active. */
  NSPointerFunctionsStrongMemory = (0<<0),

  /** Garbage collected weak references */
  NSPointerFunctionsZeroingWeakMemory = (1<<0),

  /** Non-GC memory */
  NSPointerFunctionsOpaqueMemory = (2<<0),

  /** Heap (calloc/free) memory */
  NSPointerFunctionsMallocMemory = (3<<0),

  /** MACH virtual memory (not implemented) */
  NSPointerFunctionsMachVirtualMemory = (4<<0),

  /** Uses read and write barriers appropriate for either automatic reference
   * counting or garbage collection.  Note that the GNUstep implementation will
   * behave correctly when used with manual or automatic reference counting, as
   * long as the Objective-C runtime supports automatic reference counting.
   */
  NSPointerFunctionsWeakMemory = (5<<0),

  /** Use the -hash and -isEqual: methods for storing objects, and the
   * -description method to describe them. */
  NSPointerFunctionsObjectPersonality = (0<<8),

  /** Use the pointer (shifted) as a hash, and compare for bitwise quality.
   */
  NSPointerFunctionsOpaquePersonality = (1<<8),

  /** Use the pointer (shifted) as a hash, and compare for bitwise quality,
   * but use -description to desribe the objects.
   */
  NSPointerFunctionsObjectPointerPersonality = (2<<8),

  /** Use strcmp for comparison and a hash of the string contents.  Describe
   * assuming that the string contains UTF-8 data.
   */
  NSPointerFunctionsCStringPersonality = (3<<8),

  /** Use memcmp for comparison and a hash of the sructure contents.
   * A size function must be set so that the size of the memcmp and hash
   * are known,
   */
  NSPointerFunctionsStructPersonality = (4<<8),

  /** Use unmodified integer value for both hash and equality test.
   */
  NSPointerFunctionsIntegerPersonality = (5<<8),


  /** Request the memory acquire function to allocate/copy items.
   */
  NSPointerFunctionsCopyIn = (1<<16)
};

/** An integer value containing memory option, personality option,
 * and copying option.
 */
typedef	NSUInteger NSPointerFunctionsOptions;

@interface NSPointerFunctions : NSObject <NSCopying>

+ (id) pointerFunctionsWithOptions: (NSPointerFunctionsOptions)options;

- (id) initWithOptions: (NSPointerFunctionsOptions)options;

- (void* (*)(const void *item,
  NSUInteger (*size)(const void *item), BOOL shouldCopy)) acquireFunction;

- (NSString *(*)(const void *item)) descriptionFunction;

- (NSUInteger (*)(const void *item,
  NSUInteger (*size)(const void *item))) hashFunction;

- (BOOL (*)(const void *item1, const void *item2,
  NSUInteger (*size)(const void *item))) isEqualFunction;

- (void (*)(const void *item,
  NSUInteger (*size)(const void *item))) relinquishFunction;

- (void) setAcquireFunction: (void* (*)(const void *item,
  NSUInteger (*size)(const void *item), BOOL shouldCopy))func;

- (void) setDescriptionFunction: (NSString *(*)(const void *item))func;

- (void) setHashFunction: (NSUInteger (*)(const void *item,
  NSUInteger (*size)(const void *item)))func;

- (void) setIsEqualFunction: (BOOL (*)(const void *item1, const void *item2,
  NSUInteger (*size)(const void *item)))func;

- (void) setRelinquishFunction: (void (*)(const void *item,
  NSUInteger (*size)(const void *item))) func;

- (void) setSizeFunction: (NSUInteger (*)(const void *item))func;

- (void) setUsesStrongWriteBarrier: (BOOL)flag;

- (void) setUsesWeakReadAndWriteBarriers: (BOOL)flag;

- (NSUInteger (*)(const void *item)) sizeFunction;

- (BOOL) usesStrongWriteBarrier;

- (BOOL) usesWeakReadAndWriteBarriers;

@end

#if	defined(__cplusplus)
}
#endif

#endif /* OS_API_VERSION(MAC_OS_X_VERSION_10_5, GS_API_LATEST) */
#endif /* __NSPointerFunctions_h_GNUSTEP_BASE_INCLUDE */
