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28 #include "WebCommon.h"
33 // Always an integer value.
34 typedef uintptr_t PlatformThreadId;
36 // Provides an interface to an embedder-defined thread implementation.
38 // Deleting the thread blocks until all pending, non-delayed tasks have been
40 class BLINK_PLATFORM_EXPORT WebThread {
45 virtual void run() = 0;
48 class BLINK_PLATFORM_EXPORT TaskObserver {
50 virtual ~TaskObserver() { }
51 virtual void willProcessTask() = 0;
52 virtual void didProcessTask() = 0;
55 // postTask() and postDelayedTask() take ownership of the passed Task
56 // object. It is safe to invoke postTask() and postDelayedTask() from any
58 virtual void postTask(Task*) = 0;
59 virtual void postDelayedTask(Task*, long long delayMs) = 0;
61 virtual bool isCurrentThread() const = 0;
62 virtual PlatformThreadId threadId() const { return 0; }
64 virtual void addTaskObserver(TaskObserver*) { }
65 virtual void removeTaskObserver(TaskObserver*) { }
67 // enterRunLoop() processes tasks posted to this WebThread. This call does not return until some task calls exitRunLoop().
68 // WebThread does not support nesting, meaning that once the run loop is entered for a given WebThread it is not valid to
69 // call enterRunLoop() again.
70 virtual void enterRunLoop() = 0;
72 // exitRunLoop() runs tasks until there are no tasks available to run, then returns control to the caller of enterRunLoop().
73 // Must be called when the WebThread is running.
74 virtual void exitRunLoop() = 0;
76 virtual ~WebThread() { }