MYUtilities: Target.m@5588347dfcbd

     1 //

     2 //  Target.m

     3 //  MYUtilities

     4 //

     5 //  Created by Jens Alfke on 2/11/08.

     6 //  Copyright 2008 Jens Alfke. All rights reserved.

     7 //

     9 #import "Target.h"

    12 @implementation MYTarget

    15 - (id) initWithReceiver: (id)receiver action: (SEL)action

    16 {

    17     self = [super init];

    18     if( self ) {

    19         NSMethodSignature *sig = [receiver methodSignatureForSelector: action];

    20         CAssert(sig,@"%@<%p> does not respond to %@",[receiver class],receiver,NSStringFromSelector(action));

    21         CAssert(sig.numberOfArguments==3,

    22                @"-[%@ %@] can't be used as a target because it takes >1 param",

    23                [receiver class],NSStringFromSelector(action));

    24         CAssert(0==strcmp([sig getArgumentTypeAtIndex: 2],"@"),

    25                @"-[%@ %@] can't be used as a target because it takes a non-object param",

    26                [receiver class],NSStringFromSelector(action));

    27         NSInvocation *inv = [NSInvocation invocationWithMethodSignature: sig];

    28         inv.target = receiver;

    29         inv.selector = action;

    30         _invocations = [inv retain];

    31     }

    32     return self;

    33 }

    35 + (MYTarget*) targetWithReceiver: (id)receiver action: (SEL)action

    36 {

    37     return [[[self alloc] initWithReceiver: receiver action: action] autorelease];

    38 }

    40 - (void) dealloc

    41 {

    42     [_invocations release];

    43     [super dealloc];

    44 }

    47 - (NSArray*) invocations

    48 {

    49     NSMutableArray *invocations = $castIf(NSMutableArray,_invocations);

    50     if( ! invocations )

    51         invocations = [NSMutableArray arrayWithObject: _invocations];

    52     return invocations;

    53 }

    56 - (NSString*) description

    57 {

    58     NSMutableString *desc = [NSMutableString stringWithFormat: @"%@{", self.class];

    59     BOOL first = YES;

    60     for( NSInvocation *inv in self.invocations ) {

    61         if( first )

    62             first = NO;

    63         else

    64             [desc appendString: @", "];

    65         [desc appendFormat: @"-[%@ %s]", [inv.target class], inv.selector];

    66     }

    67     [desc appendString: @"}"];

    68     return desc;

    69 }

    72 static BOOL equalInvocations( NSInvocation *a, NSInvocation *b )

    73 {

    74     return a.target==b.target && a.selector==b.selector;

    75 }

    78 - (BOOL) isEqual: (MYTarget*)t

    79 {

    80     if( ! [t isKindOfClass: [self class]] )

    81         return NO;

    82     if( [_invocations isKindOfClass: [NSInvocation class]] && [t->_invocations isKindOfClass: [NSInvocation class]] )

    83         return equalInvocations(_invocations,t->_invocations);

    84     NSArray *myInvocations = self.invocations, *itsInvocations = t.invocations;

    85     unsigned n = myInvocations.count;

    86     if( n != itsInvocations.count )

    87         return NO;

    88     for( int i=0; i<n; i++ )

    89         if( ! equalInvocations( [myInvocations objectAtIndex: i],

    90                                 [itsInvocations objectAtIndex: i] ) )

    91             return NO;

    92     return YES;

    93 }

    96 - (void) addTarget: (MYTarget*)target

    97 {

    98     setObj(&_invocations,[self invocations]);

    99     [_invocations addObjectsFromArray: target.invocations];

   100 }

   103 static id invokeSingleTarget( NSInvocation *invocation, id param )

   104 {

   105     id result = nil;

   106     if( invocation && invocation.target ) {

   107         [invocation retain];

   108         @try{

   109             [invocation setArgument: &param atIndex: 2];

   110             [invocation invoke];

   112             NSMethodSignature *sig = invocation.methodSignature;

   113             NSUInteger returnLength = sig.methodReturnLength;

   114             if( returnLength==0 ) {

   115                 result = nil; // void

   116             } else {

   117                 const char *returnType = sig.methodReturnType;

   118                 if( returnType[0]=='@' ) {

   119                     [invocation getReturnValue: &result];

   120                 } else {

   121                     UInt8 returnBuffer[returnLength];

   122                     [invocation getReturnValue: &returnBuffer];

   123                     result = [NSValue valueWithBytes: &returnBuffer objCType: returnType];

   124                 }

   125             }

   126         }@finally{

   127             [invocation release];

   128         }

   129     }

   130     return result;

   131 }

   134 - (id) invokeWithSender: (id)sender

   135 {

   136     id result;

   137     NSMutableArray *invocations = $castIf(NSMutableArray,_invocations);

   138     if( invocations ) {

   139         result = nil;

   140         for( NSInvocation *invocation in invocations )

   141             result = invokeSingleTarget(invocation,sender);

   142     } else {

   143         result = invokeSingleTarget(_invocations,sender);

   144     }

   145     return result;

   146 }

   149 @end

author	Jens Alfke <jens@mooseyard.com>
	Wed May 07 16:47:44 2008 -0700 (2008-05-07)
changeset 8	5588347dfcbd
parent 7	59addced5e2a
child 11	e5976864dfe9
permissions	-rw-r--r--