Add SkThreadPool for managing threads.
Skia-ized from https://codereview.appspot.com/6755043/
TODO: Use SkThread and platform independent features.
Review URL: https://codereview.appspot.com/6777064
git-svn-id: http://skia.googlecode.com/svn/trunk@6217 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/utils/SkCondVar.h b/include/utils/SkCondVar.h
new file mode 100644
index 0000000..d2539e4
--- /dev/null
+++ b/include/utils/SkCondVar.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkCondVar_DEFINED
+#define SkCondVar_DEFINED
+
+#include <pthread.h>
+
+class SkCondVar {
+public:
+ SkCondVar();
+ ~SkCondVar();
+
+ void lock();
+ void unlock();
+
+ /**
+ * Pause the calling thread. Will be awoken when signal() is called.
+ * Must be called while lock() is held (but gives it up while waiting).
+ */
+ void wait();
+
+ /**
+ * Wake one thread waiting on this condition. Must be called while lock()
+ * is held.
+ */
+ void signal();
+
+ /**
+ * Wake all threads waiting on this condition. Must be called while lock()
+ * is held.
+ */
+ void broadcast();
+
+private:
+ // FIXME: Make this independent of pthreads.
+ pthread_mutex_t fMutex;
+ pthread_cond_t fCond;
+};
+
+#endif
diff --git a/include/utils/SkCountdown.h b/include/utils/SkCountdown.h
new file mode 100644
index 0000000..6bcec7d
--- /dev/null
+++ b/include/utils/SkCountdown.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkCountdown_DEFINED
+#define SkCountdown_DEFINED
+
+#include "SkCondVar.h"
+#include "SkRunnable.h"
+#include "SkTypes.h"
+
+class SkCountdown : public SkRunnable {
+public:
+ explicit SkCountdown(int32_t count);
+
+ /**
+ * Resets the countdown to the count provided.
+ */
+ void reset(int32_t count);
+
+ virtual void run() SK_OVERRIDE;
+
+ /**
+ * Blocks until run() has been called count times.
+ */
+ void wait();
+
+private:
+ SkCondVar fReady;
+ int32_t fCount;
+};
+
+#endif
diff --git a/include/utils/SkRunnable.h b/include/utils/SkRunnable.h
new file mode 100644
index 0000000..c7bedcc
--- /dev/null
+++ b/include/utils/SkRunnable.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkRunnable_DEFINED
+#define SkRunnable_DEFINED
+
+class SkRunnable {
+public:
+ virtual void run() = 0;
+};
+
+#endif
diff --git a/include/utils/SkThreadPool.h b/include/utils/SkThreadPool.h
new file mode 100644
index 0000000..a96f87b
--- /dev/null
+++ b/include/utils/SkThreadPool.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkThreadPool_DEFINED
+#define SkThreadPool_DEFINED
+
+#include "SkCondVar.h"
+#include "SkTDArray.h"
+#include "SkTDLinkedList.h"
+
+class SkRunnable;
+class SkThread;
+
+class SkThreadPool {
+
+public:
+ /**
+ * Create a threadpool with exactly count (>=0) threads.
+ */
+ explicit SkThreadPool(int count);
+ ~SkThreadPool();
+
+ /**
+ * Queues up an SkRunnable to run when a thread is available, or immediately if
+ * count is 0. NULL is a safe no-op. Does not take ownership.
+ */
+ void add(SkRunnable*);
+
+ private:
+ struct LinkedRunnable {
+ // Unowned pointer.
+ SkRunnable* fRunnable;
+
+ private:
+ SK_DEFINE_DLINKEDLIST_INTERFACE(LinkedRunnable)
+ };
+
+ SkTDLinkedList<LinkedRunnable> fQueue;
+ SkCondVar fReady;
+ SkTDArray<SkThread*> fThreads;
+ bool fDone;
+
+ static void Loop(void*); // Static because we pass in this.
+};
+
+#endif