[NAN] Add LV utilities (TLV with T size of 0). (009b1fcb) · Commits · e / os / android_frameworks_base

wifi/java/android/net/wifi/nan/LvBufferUtils.java

0 → 100644

+340 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2016 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.
		*/

		package android.net.wifi.nan;

		import android.annotation.Nullable;

		import libcore.io.Memory;

		import java.nio.ByteOrder;
		import java.util.Iterator;

		/**
		* Utility class to construct and parse byte arrays using the LV format -
		* Length/Value format. The utilities accept a configuration of the size of
		* the Length field.
		*
		* @hide PROPOSED_NAN_API
		*/
		public class LvBufferUtils {
		private LvBufferUtils() {
		// no reason to ever create this class
		}

		/**
		* Utility class to construct byte arrays using the LV format - Length/Value.
		* <p>
		* A constructor is created specifying the size of the Length (L) field.
		* <p>
		* The byte array is either provided (using
		* {@link LvBufferUtils.LvConstructor#wrap(byte[])}) or allocated (using
		* {@link LvBufferUtils.LvConstructor#allocate(int)}).
		* <p>
		* Values are added to the structure using the {@code LvConstructor.put*()}
		* methods.
		* <p>
		* The final byte array is obtained using {@link LvBufferUtils.LvConstructor#getArray()}.
		*/
		public static class LvConstructor {
		private TlvBufferUtils.TlvConstructor mTlvImpl;

		/**
		* Define a LV constructor with the specified size of the Length (L) field.
		*
		* @param lengthSize Number of bytes used for the Length (L) field.
		* Values of 1 or 2 bytes are allowed.
		*/
		public LvConstructor(int lengthSize) {
		mTlvImpl = new TlvBufferUtils.TlvConstructor(0, lengthSize);
		}

		/**
		* Set the byte array to be used to construct the LV.
		*
		* @param array Byte array to be formatted.
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor wrap(@Nullable byte[] array) {
		mTlvImpl.wrap(array);
		return this;
		}

		/**
		* Allocates a new byte array to be used ot construct a LV.
		*
		* @param capacity The size of the byte array to be allocated.
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor allocate(int capacity) {
		mTlvImpl.allocate(capacity);
		return this;
		}

		/**
		* Copies a byte into the LV array.
		*
		* @param b The byte to be inserted into the structure.
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor putByte(byte b) {
		mTlvImpl.putByte(0, b);
		return this;
		}

		/**
		* Copies a byte array into the LV.
		*
		* @param array The array to be copied into the LV structure.
		* @param offset Start copying from the array at the specified offset.
		* @param length Copy the specified number (length) of bytes from the
		* array.
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor putByteArray(@Nullable byte[] array, int offset,
		int length) {
		mTlvImpl.putByteArray(0, array, offset, length);
		return this;
		}

		/**
		* Copies a byte array into the LV.
		*
		* @param array The array to be copied (in full) into the LV structure.
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor putByteArray(int type, @Nullable byte[] array) {
		return putByteArray(array, 0, (array == null) ? 0 : array.length);
		}

		/**
		* Places a zero length element (i.e. Length field = 0) into the LV.
		*
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor putZeroLengthElement() {
		mTlvImpl.putZeroLengthElement(0);
		return this;
		}

		/**
		* Copies short into the LV.
		*
		* @param data The short to be inserted into the structure.
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor putShort(short data) {
		mTlvImpl.putShort(0, data);
		return this;
		}

		/**
		* Copies integer into the LV.
		*
		* @param data The integer to be inserted into the structure.
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor putInt(int data) {
		mTlvImpl.putInt(0, data);
		return this;
		}

		/**
		* Copies a String's byte representation into the LV.
		*
		* @param data The string whose bytes are to be inserted into the
		* structure.
		* @return The constructor to facilitate chaining
		* {@code ctr.putXXX(..).putXXX(..)}.
		*/
		public LvBufferUtils.LvConstructor putString(@Nullable String data) {
		mTlvImpl.putString(0, data);
		return this;
		}

		/**
		* Returns the constructed LV formatted byte-array. This array is a copy of the wrapped
		* or allocated array - truncated to just the significant bytes - i.e. those written into
		* the LV.
		*
		* @return The byte array containing the LV formatted structure.
		*/
		public byte[] getArray() {
		return mTlvImpl.getArray();
		}
		}

		/**
		* Utility class used when iterating over an LV formatted byte-array. Use
		* {@link LvBufferUtils.LvIterable} to iterate over array. A {@link LvBufferUtils.LvElement}
		* represents each entry in a LV formatted byte-array.
		*/
		public static class LvElement {
		/**
		* The Length (L) field of the current LV element.
		*/
		public int length;

		/**
		* The Value (V) field - a raw byte array representing the current LV
		* element where the entry starts at {@link LvBufferUtils.LvElement#offset}.
		*/
		public byte[] refArray;

		/**
		* The offset to be used into {@link LvBufferUtils.LvElement#refArray} to access the
		* raw data representing the current LV element.
		*/
		public int offset;

		private LvElement(int length, @Nullable byte[] refArray, int offset) {
		this.length = length;
		this.refArray = refArray;
		this.offset = offset;
		}

		/**
		* Utility function to return a byte representation of a LV element of
		* length 1. Note: an attempt to call this function on a LV item whose
		* {@link LvBufferUtils.LvElement#length} is != 1 will result in an exception.
		*
		* @return byte representation of current LV element.
		*/
		public byte getByte() {
		if (length != 1) {
		throw new IllegalArgumentException(
		"Accesing a byte from a LV element of length " + length);
		}
		return refArray[offset];
		}

		/**
		* Utility function to return a short representation of a LV element of
		* length 2. Note: an attempt to call this function on a LV item whose
		* {@link LvBufferUtils.LvElement#length} is != 2 will result in an exception.
		*
		* @return short representation of current LV element.
		*/
		public short getShort() {
		if (length != 2) {
		throw new IllegalArgumentException(
		"Accesing a short from a LV element of length " + length);
		}
		return Memory.peekShort(refArray, offset, ByteOrder.BIG_ENDIAN);
		}

		/**
		* Utility function to return an integer representation of a LV element
		* of length 4. Note: an attempt to call this function on a LV item
		* whose {@link LvBufferUtils.LvElement#length} is != 4 will result in an exception.
		*
		* @return integer representation of current LV element.
		*/
		public int getInt() {
		if (length != 4) {
		throw new IllegalArgumentException(
		"Accesing an int from a LV element of length " + length);
		}
		return Memory.peekInt(refArray, offset, ByteOrder.BIG_ENDIAN);
		}

		/**
		* Utility function to return a String representation of a LV element.
		*
		* @return String representation of the current LV element.
		*/
		public String getString() {
		return new String(refArray, offset, length);
		}
		}

		/**
		* Utility class to iterate over a LV formatted byte-array.
		*/
		public static class LvIterable implements Iterable<LvBufferUtils.LvElement> {
		private final TlvBufferUtils.TlvIterable mTlvIterable;

		/**
		* Constructs an LvIterable object - specifying the format of the LV
		* (the size of the Length field), and the byte array whose data is to be parsed.
		*
		* @param lengthSize Number of bytes sued for the Length (L) field.
		* Values values are 1 or 2 bytes.
		* @param array The LV formatted byte-array to parse.
		*/
		public LvIterable(int lengthSize, @Nullable byte[] array) {
		mTlvIterable = new TlvBufferUtils.TlvIterable(0, lengthSize, array);
		}

		/**
		* Prints out a parsed representation of the LV-formatted byte array.
		* Whenever possible bytes, shorts, and integer are printed out (for
		* fields whose length is 1, 2, or 4 respectively).
		*/
		@Override
		public String toString() {
		return mTlvIterable.toString();
		}

		/**
		* Returns an iterator to step through a LV formatted byte-array. The
		* individual elements returned by the iterator are {@link LvBufferUtils.LvElement}.
		*/
		@Override
		public Iterator<LvBufferUtils.LvElement> iterator() {
		return new Iterator<LvBufferUtils.LvElement>() {
		private Iterator<TlvBufferUtils.TlvElement> mTlvIterator = mTlvIterable.iterator();

		@Override
		public boolean hasNext() {
		return mTlvIterator.hasNext();
		}

		@Override
		public LvBufferUtils.LvElement next() {
		TlvBufferUtils.TlvElement tlvE = mTlvIterator.next();

		return new LvElement(tlvE.length, tlvE.refArray, tlvE.offset);
		}

		@Override
		public void remove() {
		throw new UnsupportedOperationException();
		}
		};
		}
		}

		/**
		* Validates that a LV array is constructed correctly. I.e. that its specified Length
		* fields correctly fill the specified length (and do not overshoot).
		*
		* @param array The LV array to verify.
		* @param lengthSize The size (in bytes) of the length field. Valid values are 1 or 2.
		* @return A boolean indicating whether the array is valid (true) or invalid (false).
		*/
		public static boolean isValid(@Nullable byte[] array, int lengthSize) {
		return TlvBufferUtils.isValid(array, 0, lengthSize);
		}
		}

wifi/java/android/net/wifi/nan/PublishConfig.java

+6 −6

Original line number	Diff line number	Diff line
		@@ -116,8 +116,8 @@ public class PublishConfig implements Parcelable {
		public String toString() {
		return "PublishConfig [mServiceName='" + mServiceName + ", mServiceSpecificInfo='" + (
		(mServiceSpecificInfo == null) ? "null" : HexEncoding.encode(mServiceSpecificInfo))
		+ ", mTxFilter=" + (new TlvBufferUtils.TlvIterable(0, 1, mTxFilter)).toString()
		+ ", mRxFilter=" + (new TlvBufferUtils.TlvIterable(0, 1, mRxFilter)).toString()
		+ ", mTxFilter=" + (new LvBufferUtils.LvIterable(1, mTxFilter)).toString()
		+ ", mRxFilter=" + (new LvBufferUtils.LvIterable(1, mRxFilter)).toString()
		+ ", mPublishType=" + mPublishType + ", mPublishCount=" + mPublishCount
		+ ", mTtlSec=" + mTtlSec + ", mEnableTerminateNotification="
		+ mEnableTerminateNotification + "]";
		@@ -206,11 +206,11 @@ public class PublishConfig implements Parcelable {
		public void validate() throws IllegalArgumentException {
		WifiNanUtils.validateServiceName(mServiceName);

		if (!TlvBufferUtils.isValid(mTxFilter, 0, 1)) {
		if (!LvBufferUtils.isValid(mTxFilter, 1)) {
		throw new IllegalArgumentException(
		"Invalid txFilter configuration - LV fields do not match up to length");
		}
		if (!TlvBufferUtils.isValid(mRxFilter, 0, 1)) {
		if (!LvBufferUtils.isValid(mRxFilter, 1)) {
		throw new IllegalArgumentException(
		"Invalid rxFilter configuration - LV fields do not match up to length");
		}
		@@ -310,7 +310,7 @@ public class PublishConfig implements Parcelable {
		* determine whether they match - in addition to just relying on the
		* service name.
		* <p>
		* Format is an LV byte array - the {@link TlvBufferUtils} utility class
		* Format is an LV byte array - the {@link LvBufferUtils} utility class
		* is available to form and parse.
		*
		* @param txFilter The byte-array containing the LV formatted transmit
		@@ -331,7 +331,7 @@ public class PublishConfig implements Parcelable {
		* (active subscribers) - in addition to just relying on the service
		* name.
		* <p>
		* Format is an LV byte array - the {@link TlvBufferUtils} utility class
		* Format is an LV byte array - the {@link LvBufferUtils} utility class
		* is available to form and parse.
		*
		* @param rxFilter The byte-array containing the LV formatted receive

wifi/java/android/net/wifi/nan/SubscribeConfig.java

+6 −6

Original line number	Diff line number	Diff line
		@@ -140,8 +140,8 @@ public class SubscribeConfig implements Parcelable {
		public String toString() {
		return "SubscribeConfig [mServiceName='" + mServiceName + ", mServiceSpecificInfo='" + (
		(mServiceSpecificInfo == null) ? "null" : HexEncoding.encode(mServiceSpecificInfo))
		+ ", mTxFilter=" + (new TlvBufferUtils.TlvIterable(0, 1, mTxFilter)).toString()
		+ ", mRxFilter=" + (new TlvBufferUtils.TlvIterable(0, 1, mRxFilter)).toString()
		+ ", mTxFilter=" + (new LvBufferUtils.LvIterable(1, mTxFilter)).toString()
		+ ", mRxFilter=" + (new LvBufferUtils.LvIterable(1, mRxFilter)).toString()
		+ ", mSubscribeType=" + mSubscribeType + ", mSubscribeCount=" + mSubscribeCount
		+ ", mTtlSec=" + mTtlSec + ", mMatchType=" + mMatchStyle
		+ ", mEnableTerminateNotification=" + mEnableTerminateNotification + "]";
		@@ -234,11 +234,11 @@ public class SubscribeConfig implements Parcelable {
		public void validate() throws IllegalArgumentException {
		WifiNanUtils.validateServiceName(mServiceName);

		if (!TlvBufferUtils.isValid(mTxFilter, 0, 1)) {
		if (!LvBufferUtils.isValid(mTxFilter, 1)) {
		throw new IllegalArgumentException(
		"Invalid txFilter configuration - LV fields do not match up to length");
		}
		if (!TlvBufferUtils.isValid(mRxFilter, 0, 1)) {
		if (!LvBufferUtils.isValid(mRxFilter, 1)) {
		throw new IllegalArgumentException(
		"Invalid rxFilter configuration - LV fields do not match up to length");
		}
		@@ -344,7 +344,7 @@ public class SubscribeConfig implements Parcelable {
		* publishers) to determine whether they match - in addition to just
		* relying on the service name.
		* <p>
		* Format is an LV byte array - the {@link TlvBufferUtils} utility class
		* Format is an LV byte array - the {@link LvBufferUtils} utility class
		* is available to form and parse.
		*
		* @param txFilter The byte-array containing the LV formatted transmit
		@@ -364,7 +364,7 @@ public class SubscribeConfig implements Parcelable {
		* subscriber to determine whether they match transmitted publish
		* packets - in addition to just relying on the service name.
		* <p>
		* Format is an LV byte array - the {@link TlvBufferUtils} utility class
		* Format is an LV byte array - the {@link LvBufferUtils} utility class
		* is available to form and parse.
		*
		* @param rxFilter The byte-array containing the LV formatted receive