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/*
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package sun.nio.ch;

import java.lang.annotation.Native;

Manipulates a native array of structs corresponding to (fd, events) pairs. typedef struct pollfd { SOCKET fd; // 4 bytes short events; // 2 bytes } pollfd_t;
Author:Konstantin Kladko, Mike McCloskey
/** * Manipulates a native array of structs corresponding to (fd, events) pairs. * * typedef struct pollfd { * SOCKET fd; // 4 bytes * short events; // 2 bytes * } pollfd_t; * * @author Konstantin Kladko * @author Mike McCloskey */
class PollArrayWrapper { private AllocatedNativeObject pollArray; // The fd array long pollArrayAddress; // pollArrayAddress @Native private static final short FD_OFFSET = 0; // fd offset in pollfd @Native private static final short EVENT_OFFSET = 4; // events offset in pollfd static short SIZE_POLLFD = 8; // sizeof pollfd struct private int size; // Size of the pollArray PollArrayWrapper(int newSize) { int allocationSize = newSize * SIZE_POLLFD; pollArray = new AllocatedNativeObject(allocationSize, true); pollArrayAddress = pollArray.address(); this.size = newSize; } // Prepare another pollfd struct for use. void putEntry(int index, SelectionKeyImpl ski) { putDescriptor(index, ski.getFDVal()); putEventOps(index, 0); } // Writes the pollfd entry from the source wrapper at the source index // over the entry in the target wrapper at the target index. void replaceEntry(PollArrayWrapper source, int sindex, PollArrayWrapper target, int tindex) { target.putDescriptor(tindex, source.getDescriptor(sindex)); target.putEventOps(tindex, source.getEventOps(sindex)); } // Grows the pollfd array to new size void grow(int newSize) { PollArrayWrapper temp = new PollArrayWrapper(newSize); for (int i = 0; i < size; i++) replaceEntry(this, i, temp, i); pollArray.free(); pollArray = temp.pollArray; this.size = temp.size; pollArrayAddress = pollArray.address(); } void free() { pollArray.free(); } // Access methods for fd structures void putDescriptor(int i, int fd) { pollArray.putInt(SIZE_POLLFD * i + FD_OFFSET, fd); } void putEventOps(int i, int event) { pollArray.putShort(SIZE_POLLFD * i + EVENT_OFFSET, (short)event); } int getEventOps(int i) { return pollArray.getShort(SIZE_POLLFD * i + EVENT_OFFSET); } int getDescriptor(int i) { return pollArray.getInt(SIZE_POLLFD * i + FD_OFFSET); } // Adds Windows wakeup socket at a given index. void addWakeupSocket(int fdVal, int index) { putDescriptor(index, fdVal); putEventOps(index, Net.POLLIN); } }