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diff --git a/include/cutils/selector.h b/include/cutils/selector.h
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+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Framework for multiplexing I/O. A selector manages a set of file
+ * descriptors and calls out to user-provided callback functions to read and
+ * write data and handle errors.
+ */
+
+#ifndef __SELECTOR_H
+#define __SELECTOR_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdbool.h>
+    
+/** 
+ * Manages SelectableFds and invokes their callbacks at appropriate times. 
+ */
+typedef struct Selector Selector;
+
+/** 
+ * A selectable descriptor. Contains callbacks which the selector can invoke
+ * before calling select(), when the descriptor is readable or writable, and 
+ * when the descriptor contains out-of-band data. Simply set a callback to 
+ * NULL if you're not interested in that particular event.
+ *
+ * A selectable descriptor can indicate that it needs to be removed from the
+ * selector by setting the 'remove' flag. The selector will remove the
+ * descriptor at a later time and invoke the onRemove() callback.
+ * 
+ * SelectableFd fields should only be modified from the selector loop.
+ */
+typedef struct SelectableFd SelectableFd;
+struct SelectableFd {
+
+    /** The file descriptor itself. */
+    int fd;
+    
+    /** Pointer to user-specific data. Can be NULL. */
+    void* data;
+    
+    /** 
+     * Set this flag when you no longer wish to be selected. The selector
+     * will invoke onRemove() when the descriptor is actually removed.
+     */
+    bool remove;
+
+    /** 
+     * Invoked by the selector before calling select. You can set up other
+     * callbacks from here as necessary.
+     */
+    void (*beforeSelect)(SelectableFd* self);
+
+    /** 
+     * Invoked by the selector when the descriptor has data available. Set to
+     * NULL to indicate that you're not interested in reading.
+     */
+    void (*onReadable)(SelectableFd* self);
+
+    /** 
+     * Invoked by the selector when the descriptor can accept data. Set to
+     * NULL to indicate that you're not interested in writing.
+     */
+    void (*onWritable)(SelectableFd* self);
+
+    /** 
+     * Invoked by the selector when out-of-band (OOB) data is available. Set to
+     * NULL to indicate that you're not interested in OOB data.
+     */
+    void (*onExcept)(SelectableFd* self);
+
+    /**
+     * Invoked by the selector after the descriptor is removed from the
+     * selector but before the selector frees the SelectableFd memory.
+     */
+    void (*onRemove)(SelectableFd* self);
+
+    /**
+     * The selector which selected this fd. Set by the selector itself.
+     */
+    Selector* selector;
+};
+
+/** 
+ * Creates a new selector. 
+ */
+Selector* selectorCreate(void);
+
+/** 
+ * Creates a new selectable fd, adds it to the given selector and returns a 
+ * pointer. Outside of 'selector' and 'fd', all fields are set to 0 or NULL 
+ * by default.
+ * 
+ * The selectable fd should only be modified from the selector loop thread.
+ */
+SelectableFd* selectorAdd(Selector* selector, int fd);
+
+/**
+ * Wakes up the selector even though no I/O events occurred. Use this
+ * to indicate that you're ready to write to a descriptor.
+ */
+void selectorWakeUp(Selector* selector);
+    
+/** 
+ * Loops continuously selecting file descriptors and firing events. 
+ * Does not return. 
+ */
+void selectorLoop(Selector* selector);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __SELECTOR_H */