keychain/ckks/NSOperationCategories.m

   1 /*
   2  * Copyright (c) 2017 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 #import <Foundation/Foundation.h>
  25 #import "keychain/ckks/NSOperationCategories.h"
  26 #import "keychain/ot/ObjCImprovements.h"
  27
  28 @implementation NSOperation (CKKSUsefulPrintingOperation)
  29 - (NSString*)selfname {
  30     if(self.name) {
  31         return [NSString stringWithFormat: @"%@(%@)", NSStringFromClass([self class]), self.name];
  32     } else {
  33         return NSStringFromClass([self class]);
  34     }
  35 }
  36
  37 -(void)linearDependencies: (NSHashTable*) collection {
  38     @synchronized(collection) {
  39         for(NSOperation* existingop in collection) {
  40             if(existingop == self) {
  41                 // don't depend on yourself
  42                 continue;
  43             }
  44             [self addDependency: existingop];
  45         }
  46         [collection addObject:self];
  47     }
  48 }
  49
  50 -(void)linearDependenciesWithSelfFirst: (NSHashTable*) collection {
  51     @synchronized(collection) {
  52         for(NSOperation* existingop in collection) {
  53             if(existingop == self) {
  54                 // don't depend on yourself
  55                 continue;
  56             }
  57
  58             if([existingop isPending]) {
  59                 [existingop addDependency: self];
  60                 if([existingop isPending]) {
  61                     // Good, we're ahead of this one.
  62                 } else {
  63                     // It started before we told it to wait on us. Reverse the dependency.
  64                     [existingop removeDependency: self];
  65                     [self addDependency:existingop];
  66                 }
  67             } else {
  68                 // Not a pending op? We depend on it.
  69                 [self addDependency: existingop];
  70             }
  71         }
  72         [collection addObject:self];
  73     }
  74 }
  75
  76 -(NSString*)pendingDependenciesString:(NSString*)prefix {
  77     NSArray* dependencies = [self.dependencies copy];
  78     dependencies = [dependencies objectsAtIndexes: [dependencies indexesOfObjectsPassingTest: ^BOOL (id obj,
  79                                                                                                      NSUInteger idx,
  80                                                                                                      BOOL* stop) {
  81         return [obj isFinished] ? NO : YES;
  82     }]];
  83
  84     if(dependencies.count == 0u) {
  85         return @"";
  86     }
  87
  88     return [NSString stringWithFormat: @"%@%@", prefix, [dependencies componentsJoinedByString: @", "]];
  89 }
  90
  91 - (NSString*)description {
  92     NSString* state = ([self isFinished] ? @"finished" :
  93                        [self isCancelled] ? @"cancelled" :
  94                        [self isExecuting] ? @"executing" :
  95                        [self isReady] ? @"ready" :
  96                        @"pending");
  97
  98     return [NSString stringWithFormat: @"<%@: %@%@>", [self selfname], state, [self pendingDependenciesString: @" dep:"]];
  99 }
 100 - (NSString*)debugDescription {
 101     NSString* state = ([self isFinished] ? @"finished" :
 102                        [self isCancelled] ? @"cancelled" :
 103                        [self isExecuting] ? @"executing" :
 104                        [self isReady] ? @"ready" :
 105                        @"pending");
 106
 107     return [NSString stringWithFormat: @"<%@ (%p): %@%@>", [self selfname], self, state, [self pendingDependenciesString: @" dep:"]];
 108 }
 109
 110 - (BOOL)isPending {
 111     return (!([self isExecuting] || [self isFinished] || [self isCancelled])) ? YES : NO;
 112 }
 113
 114 - (void)addNullableDependency: (NSOperation*) op {
 115     if(op) {
 116         [self addDependency:op];
 117     }
 118 }
 119
 120 - (void)removeDependenciesUponCompletion
 121 {
 122     WEAKIFY(self);
 123     self.completionBlock = ^{
 124         STRONGIFY(self);
 125         for (NSOperation *op in self.dependencies) {
 126             [self removeDependency:op];
 127         }
 128     };
 129 }
 130
 131 @end
 132
 133 @implementation NSBlockOperation (CKKSUsefulConstructorOperation)
 134 +(instancetype)named: (NSString*)name withBlock: (void(^)(void)) block {
 135     // How many blocks could a block block if a block could block blocks?
 136     NSBlockOperation* blockOp = [NSBlockOperation blockOperationWithBlock: block];
 137     blockOp.name = name;
 138     return blockOp;
 139 }
 140 @end