1 /* 2 * Copyright (C) 2007, 2008 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #import "config.h" 30 #import "MainThread.h" 31 32 #import <CoreFoundation/CoreFoundation.h> 33 #import <Foundation/NSThread.h> 34 #import <stdio.h> 35 #import <wtf/Assertions.h> 36 #import <wtf/Threading.h> 37 38 @interface WTFMainThreadCaller : NSObject { 39 } 40 - (void)call; 41 @end 42 43 @implementation WTFMainThreadCaller 44 45 - (void)call 46 { 47 WTF::dispatchFunctionsFromMainThread(); 48 } 49 50 @end // implementation WTFMainThreadCaller 51 52 namespace WTF { 53 54 static WTFMainThreadCaller* staticMainThreadCaller; 55 static bool isTimerPosted; // This is only accessed on the 'main' thread. 56 static bool mainThreadEstablishedAsPthreadMain; 57 static pthread_t mainThreadPthread; 58 static NSThread* mainThreadNSThread; 59 60 void initializeMainThreadPlatform() 61 { 62 #if !defined(BUILDING_ON_TIGER) 63 ASSERT(!staticMainThreadCaller); 64 staticMainThreadCaller = [[WTFMainThreadCaller alloc] init]; 65 66 mainThreadEstablishedAsPthreadMain = false; 67 mainThreadPthread = pthread_self(); 68 mainThreadNSThread = [[NSThread currentThread] retain]; 69 #else 70 ASSERT_NOT_REACHED(); 71 #endif 72 } 73 74 void initializeMainThreadToProcessMainThreadPlatform() 75 { 76 if (!pthread_main_np()) 77 NSLog(@"WebKit Threading Violation - initial use of WebKit from a secondary thread."); 78 79 ASSERT(!staticMainThreadCaller); 80 staticMainThreadCaller = [[WTFMainThreadCaller alloc] init]; 81 82 mainThreadEstablishedAsPthreadMain = true; 83 mainThreadPthread = 0; 84 mainThreadNSThread = nil; 85 } 86 87 static void timerFired(CFRunLoopTimerRef timer, void*) 88 { 89 CFRelease(timer); 90 isTimerPosted = false; 91 WTF::dispatchFunctionsFromMainThread(); 92 } 93 94 static void postTimer() 95 { 96 ASSERT(isMainThread()); 97 98 if (isTimerPosted) 99 return; 100 101 isTimerPosted = true; 102 CFRunLoopAddTimer(CFRunLoopGetCurrent(), CFRunLoopTimerCreate(0, 0, 0, 0, 0, timerFired, 0), kCFRunLoopCommonModes); 103 } 104 105 void scheduleDispatchFunctionsOnMainThread() 106 { 107 ASSERT(staticMainThreadCaller); 108 109 if (isMainThread()) { 110 postTimer(); 111 return; 112 } 113 114 if (mainThreadEstablishedAsPthreadMain) { 115 ASSERT(!mainThreadNSThread); 116 [staticMainThreadCaller performSelectorOnMainThread:@selector(call) withObject:nil waitUntilDone:NO]; 117 return; 118 } 119 120 #if !defined(BUILDING_ON_TIGER) 121 ASSERT(mainThreadNSThread); 122 [staticMainThreadCaller performSelector:@selector(call) onThread:mainThreadNSThread withObject:nil waitUntilDone:NO]; 123 #else 124 ASSERT_NOT_REACHED(); 125 #endif 126 } 127 128 bool isMainThread() 129 { 130 if (mainThreadEstablishedAsPthreadMain) { 131 ASSERT(!mainThreadPthread); 132 return pthread_main_np(); 133 } 134 135 #if !defined(BUILDING_ON_TIGER) 136 ASSERT(mainThreadPthread); 137 return pthread_equal(pthread_self(), mainThreadPthread); 138 #else 139 ASSERT_NOT_REACHED(); 140 return false; 141 #endif 142 } 143 144 } // namespace WTF 145