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