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 #import "utilities/debugging.h"
  28
  29 @implementation NSOperation (CKKSUsefulPrintingOperation)
  30 - (NSString*)selfname {
  31     if(self.name) {
  32         return [NSString stringWithFormat: @"%@(%@)", NSStringFromClass([self class]), self.name];
  33     } else {
  34         return NSStringFromClass([self class]);
  35     }
  36 }
  37
  38 -(void)linearDependencies: (NSHashTable*) collection {
  39     @synchronized(collection) {
  40         for(NSOperation* existingop in collection) {
  41             if(existingop == self) {
  42                 // don't depend on yourself
  43                 continue;
  44             }
  45 #if DEBUG
  46             secnotice("ckks-operation", "adding dependency of %@ on %@", self, existingop);
  47 #endif
  48             [self addDependency: existingop];
  49         }
  50         [collection addObject:self];
  51     }
  52 }
  53
  54 -(void)linearDependenciesWithSelfFirst: (NSHashTable*) collection {
  55     @synchronized(collection) {
  56         for(NSOperation* existingop in collection) {
  57             if(existingop == self) {
  58                 // don't depend on yourself
  59                 continue;
  60             }
  61
  62             if([existingop isPending]) {
  63                 [existingop addDependency: self];
  64                 if([existingop isPending]) {
  65                     // Good, we're ahead of this one.
  66                 } else {
  67                     // It started before we told it to wait on us. Reverse the dependency.
  68                     [existingop removeDependency: self];
  69                     [self addDependency:existingop];
  70                 }
  71             } else {
  72                 // Not a pending op? We depend on it.
  73                 [self addDependency: existingop];
  74             }
  75         }
  76         [collection addObject:self];
  77     }
  78 }
  79
  80 -(NSString*)pendingDependenciesString:(NSString*)prefix {
  81     NSArray* dependencies = [self.dependencies copy];
  82     dependencies = [dependencies objectsAtIndexes: [dependencies indexesOfObjectsPassingTest: ^BOOL (id obj,
  83                                                                                                      NSUInteger idx,
  84                                                                                                      BOOL* stop) {
  85         return [obj isFinished] ? NO : YES;
  86     }]];
  87
  88     if(dependencies.count == 0u) {
  89         return @"";
  90     }
  91
  92     return [NSString stringWithFormat: @"%@%@", prefix, [dependencies componentsJoinedByString: @", "]];
  93 }
  94
  95 - (NSString*)description {
  96     NSString* state = ([self isFinished] ? @"finished" :
  97                        [self isCancelled] ? @"cancelled" :
  98                        [self isExecuting] ? @"executing" :
  99                        [self isReady] ? @"ready" :
 100                        @"pending");
 101
 102     return [NSString stringWithFormat: @"<%@: %@%@>", [self selfname], state, [self pendingDependenciesString: @" dep:"]];
 103 }
 104 - (NSString*)debugDescription {
 105     NSString* state = ([self isFinished] ? @"finished" :
 106                        [self isCancelled] ? @"cancelled" :
 107                        [self isExecuting] ? @"executing" :
 108                        [self isReady] ? @"ready" :
 109                        @"pending");
 110
 111     return [NSString stringWithFormat: @"<%@ (%p): %@%@>", [self selfname], self, state, [self pendingDependenciesString: @" dep:"]];
 112 }
 113
 114 - (BOOL)isPending {
 115     return (!([self isExecuting] || [self isFinished] || [self isCancelled])) ? YES : NO;
 116 }
 117
 118 - (void)addNullableDependency: (NSOperation*) op {
 119     if(op) {
 120         [self addDependency:op];
 121     }
 122 }
 123
 124 - (void)removeDependenciesUponCompletion
 125 {
 126     WEAKIFY(self);
 127     self.completionBlock = ^{
 128         STRONGIFY(self);
 129         for (NSOperation *op in self.dependencies) {
 130             [self removeDependency:op];
 131         }
 132     };
 133 }
 134
 135 @end
 136
 137 @implementation NSBlockOperation (CKKSUsefulConstructorOperation)
 138 +(instancetype)named: (NSString*)name withBlock: (void(^)(void)) block {
 139     // How many blocks could a block block if a block could block blocks?
 140     NSBlockOperation* blockOp = [NSBlockOperation blockOperationWithBlock: block];
 141     blockOp.name = name;
 142     return blockOp;
 143 }
 144 @end