runtime/Protocol.mm

   1 /*
   2  * Copyright (c) 1999-2001, 2005-2007 Apple Inc.  All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24         Protocol.h
  25         Copyright 1991-1996 NeXT Software, Inc.
  26 */
  27
  28 #include "objc-private.h"
  29
  30 #undef id
  31 #undef Class
  32
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <mach-o/dyld.h>
  36 #include <mach-o/ldsyms.h>
  37
  38 #include "Protocol.h"
  39 #include "NSObject.h"
  40
  41 // __IncompleteProtocol is used as the return type of objc_allocateProtocol().
  42
  43 // Old ABI uses NSObject as the superclass even though Protocol uses Object
  44 // because the R/R implementation for class Protocol is added at runtime
  45 // by CF, so __IncompleteProtocol would be left without an R/R implementation
  46 // otherwise, which would break ARC.
  47
  48 @interface __IncompleteProtocol : NSObject
  49 @end
  50
  51 #if __OBJC2__
  52 __attribute__((objc_nonlazy_class))
  53 #endif
  54 @implementation __IncompleteProtocol
  55 @end
  56
  57
  58 #if __OBJC2__
  59 __attribute__((objc_nonlazy_class))
  60 #endif
  61 @implementation Protocol
  62
  63 - (BOOL) conformsTo: (Protocol *)aProtocolObj
  64 {
  65     return protocol_conformsToProtocol(self, aProtocolObj);
  66 }
  67
  68 - (struct objc_method_description *) descriptionForInstanceMethod:(SEL)aSel
  69 {
  70 #if !__OBJC2__
  71     return lookup_protocol_method((struct old_protocol *)self, aSel,
  72                                   YES/*required*/, YES/*instance*/,
  73                                   YES/*recursive*/);
  74 #else
  75     return method_getDescription(protocol_getMethod((struct protocol_t *)self,
  76                                                      aSel, YES, YES, YES));
  77 #endif
  78 }
  79
  80 - (struct objc_method_description *) descriptionForClassMethod:(SEL)aSel
  81 {
  82 #if !__OBJC2__
  83     return lookup_protocol_method((struct old_protocol *)self, aSel,
  84                                   YES/*required*/, NO/*instance*/,
  85                                   YES/*recursive*/);
  86 #else
  87     return method_getDescription(protocol_getMethod((struct protocol_t *)self,
  88                                                     aSel, YES, NO, YES));
  89 #endif
  90 }
  91
  92 - (const char *)name
  93 {
  94     return protocol_getName(self);
  95 }
  96
  97 - (BOOL)isEqual:other
  98 {
  99 #if __OBJC2__
 100     // check isKindOf:
 101     Class cls;
 102     Class protoClass = objc_getClass("Protocol");
 103     for (cls = object_getClass(other); cls; cls = cls->getSuperclass()) {
 104         if (cls == protoClass) break;
 105     }
 106     if (!cls) return NO;
 107     // check equality
 108     return protocol_isEqual(self, other);
 109 #else
 110     return [other isKindOf:[Protocol class]] && [self conformsTo: other] && [other conformsTo: self];
 111 #endif
 112 }
 113
 114 #if __OBJC2__
 115 - (NSUInteger)hash
 116 {
 117     return 23;
 118 }
 119 #else
 120 - (unsigned)hash
 121 {
 122     return 23;
 123 }
 124 #endif
 125
 126 @end