1 files changed, 147 insertions, 0 deletions
diff --git a/flow-core/src/main/java/com/github/jodersky/flow/internal/NativeSerial.java b/flow-core/src/main/java/com/github/jodersky/flow/internal/NativeSerial.java
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+++ b/flow-core/src/main/java/com/github/jodersky/flow/internal/NativeSerial.java
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+package com.github.jodersky.flow.internal;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+import ch.jodersky.jni.NativeLoader;
+
+import com.github.jodersky.flow.AccessDeniedException;
+import com.github.jodersky.flow.InvalidSettingsException;
+import com.github.jodersky.flow.NoSuchPortException;
+import com.github.jodersky.flow.PortInUseException;
+import com.github.jodersky.flow.PortInterruptedException;
+
+/**
+ * Low-level wrapper on top of native serial backend. 
+ * 
+ * WARNING: Methods in this class allocate native structures and deal with pointers.
+ * These pointers are handled as longs by java and are NOT checked for correctness,
+ * therefore passing invalid pointers may have unexpected results, including but not
+ * limited to crashing the VM.
+ * 
+ * See SerialConnection for a higher level, more secured wrapper
+ * of serial communication.
+ * 
+ * @see com.github.jodersky.flow.internal.SerialConnection
+ */
+final class NativeSerial {
+	
+	static {
+		NativeLoader.load("/com/github/jodersky/flow", "flow3");
+	}
+	
+	final static int PARITY_NONE = 0;
+	final static int PARITY_ODD = 1;
+	final static int PARITY_EVEN = 2;
+	
+	/**
+	 * Opens a serial port.
+	 * 
+	 * @param port name of serial port to open
+	 * @param characterSize size of a character of the data sent through the serial port
+	 * @param twoStopBits set to use two stop bits instead of one
+	 * @param parity type of parity to use with serial port
+	 * @return address of natively allocated serial configuration structure
+	 * @throws NoSuchPortException if the given port does not exist
+	 * @throws AccessDeniedException if permissions of the current user are not sufficient to open port 
+	 * @throws PortInUseException if port is already in use
+	 * @throws InvalidSettingsException if any of the specified settings are invalid
+	 * @throws IOException on IO error
+	 */
+	native static long open(String port, int baud, int characterSize, boolean twoStopBits, int parity)
+	throws NoSuchPortException, AccessDeniedException, PortInUseException, InvalidSettingsException, IOException;
+	
+	/**
+	 * Reads from a previously opened serial port into a direct ByteBuffer. Note that data is only read into the
+	 * buffer's allocated memory, its position or limit are not changed. 
+	 *  
+	 * The read is blocking, however it may be interrupted by calling cancelRead() on the given serial port.
+	 * 
+	 * @param serial address of natively allocated serial configuration structure
+	 * @param buffer direct ByteBuffer to read into
+	 * @return number of bytes actually read
+	 * @throws IllegalArgumentException if the ByteBuffer is not direct
+	 * @throws PortInterruptedException if the call to this function was interrupted
+	 * @throws IOException on IO error
+	 */
+	native static int readDirect(long serial, ByteBuffer buffer)
+	throws IllegalArgumentException, PortInterruptedException, IOException;
+
+	/**
+	 * Reads data from a previously opened serial port into an array.
+	 * 
+	 * The read is blocking, however it may be interrupted by calling cancelRead() on the given serial port.
+	 * 
+	 * @param serial address of natively allocated serial configuration structure
+	 * @param buffer array to read data into
+	 * @return number of bytes actually read
+	 * @throws PortInterruptedException if the call to this function was interrupted
+	 * @throws IOException on IO error
+	 */
+	native static int read(long serial, byte[] buffer)
+	throws PortInterruptedException, IOException;
+	
+	/**
+	 * Cancels a read (any caller to read or readDirect will return with a PortInterruptedException). This function may be called from any thread.
+	 * 
+	 * @param serial address of natively allocated serial configuration structure
+	 * @throws IOException on IO error
+	 */
+	native static void cancelRead(long serial)
+	throws IOException;
+
+	/**
+	 * Writes data from a direct ByteBuffer to a previously opened serial port. Note that data is only taken from
+	 * the buffer's allocated memory, its position or limit are not changed.
+	 *  
+	 * The write is non-blocking, this function returns as soon as the data is copied into the kernel's
+	 * transmission buffer.
+	 * 
+	 * @param serial address of natively allocated serial configuration structure
+	 * @param buffer direct ByteBuffer from which data is taken
+	 * @param length actual amount of data that should be taken from the buffer (this is needed since the native
+	 * backend does not provide a way to query the buffer's current limit)
+	 * @return number of bytes actually written   
+	 * @throws IllegalArgumentException if the ByteBuffer is not direct
+	 * @throws IOException on IO error
+	 */
+	native static int writeDirect(long serial, ByteBuffer buffer, int length)
+	throws IllegalArgumentException, IOException;
+	
+	/**
+	 * Writes data from an array to a previously opened serial port.
+	 *  
+	 * The write is non-blocking, this function returns as soon as the data is copied into the kernel's
+	 * transmission buffer.
+	 * 
+	 * @param serial address of natively allocated serial configuration structure
+	 * @param buffer array from which data is taken
+	 * @param length actual amount of data that should be taken from the buffer
+	 * @return number of bytes actually written
+	 * @throws IOException on IO error
+	 */
+	native static int write(long serial, byte[] buffer, int length)
+	throws IOException;
+	
+	/**
+	 * Closes an previously open serial port. Natively allocated resources are freed and the serial pointer becomes invalid,
+	 * therefore this function should only be called ONCE per open serial port.
+	 * 
+	 * A port should not be closed while it is used (by a read or write) as this
+	 * results in undefined behaviour.
+	 * 
+	 * @param serial address of natively allocated serial configuration structure
+	 * @throws IOException on IO error
+	 */
+	native static void close(long serial)
+	throws IOException;
+	
+	/**
+	 * Sets native debugging mode. If debugging is enabled, detailed error messages
+	 * are printed (to stderr) from native method calls.
+	 * 
+	 * @param value set to enable debugging
+	 */
+	native static void debug(boolean value);
+
+}