Merge "add ByteArrayRingBuffer" into mm-wireless-dev

1 files changed, 153 insertions, 0 deletions

diff --git a/tests/wifitests/src/com/android/server/wifi/ByteArrayRingBufferTest.java b/tests/wifitests/src/com/android/server/wifi/ByteArrayRingBufferTest.java
new file mode 100644
index 000000000..dcf4cfbd4
--- /dev/null
+++ b/tests/wifitests/src/com/android/server/wifi/ByteArrayRingBufferTest.java
@@ -0,0 +1,153 @@
+/*
+ * 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 com.android.server.wifi.util;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+
+import android.test.suitebuilder.annotation.SmallTest;
+
+import org.junit.Test;
+
+
+/**
+ * Unit tests for {@link com.android.server.wifi.util.ByteArrayRingBuffer}.
+ */
+@SmallTest
+public class ByteArrayRingBufferTest {
+    private static final int MAX_BYTES = 10;
+
+    @Test
+    public void ctorCreatesEmptyRingBuffer() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        assertEquals(0, rb.getNumBuffers());
+    }
+
+    @Test
+    public void canAddAndRetrieveSingleElement() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data = {0};
+        assertTrue(rb.appendBuffer(data));
+        assertEquals(1, rb.getNumBuffers());
+        assertSame(data, rb.getBuffer(0));
+    }
+
+    @Test
+    public void canAddAndRetrieveMultipleElements() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data1 = {0};
+        final byte[] data2 = {1};
+        assertTrue(rb.appendBuffer(data1));
+        assertTrue(rb.appendBuffer(data2));
+        assertEquals(2, rb.getNumBuffers());
+        assertSame(data1, rb.getBuffer(0));
+        assertSame(data2, rb.getBuffer(1));
+    }
+
+    @Test
+    public void canFillToCapacityWithMultipleElements() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data1 = {1, 2, 3, 4, 5};
+        final byte[] data2 = {6, 7, 8, 9, 10};
+        assertEquals(MAX_BYTES, data1.length + data2.length);
+        assertTrue(rb.appendBuffer(data1));
+        assertTrue(rb.appendBuffer(data2));
+        assertEquals(2, rb.getNumBuffers());
+    }
+
+    @Test
+    public void canFillToCapacityWithSingleElement() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+        assertEquals(MAX_BYTES, data.length);
+        assertTrue(rb.appendBuffer(data));
+    }
+
+    @Test
+    public void canNotOverfillWithSingleElement() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};
+        assertTrue(data.length > MAX_BYTES);
+        assertFalse(rb.appendBuffer(data));
+        assertEquals(0, rb.getNumBuffers());
+    }
+
+    @Test
+    public void appendPrunesBufferIfNecessary() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data1 = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+        assertTrue(rb.appendBuffer(data1));
+
+        final byte[] data2 = {11};
+        assertTrue(rb.appendBuffer(data2));
+        assertEquals(1, rb.getNumBuffers());
+        assertSame(data2, rb.getBuffer(0));
+    }
+
+    @Test
+    public void appendPrunesMultipleBuffersIfNecessary() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data1 = {1, 2, 3, 4, 5};
+        final byte[] data2 = {6, 7, 8, 9, 10};
+        assertTrue(rb.appendBuffer(data1));
+        assertTrue(rb.appendBuffer(data2));
+
+        final byte[] data3 = {11, 12, 13, 14, 15, 16};
+        assertTrue(rb.appendBuffer(data3));
+        assertEquals(1, rb.getNumBuffers());
+        assertSame(data3, rb.getBuffer(0));
+    }
+
+    @Test
+    public void appendPrunesOnlyWhenNecessary() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data1 = {1, 2, 3, 4, 5};
+        assertTrue(rb.appendBuffer(data1));
+
+        final byte[] data2 = {6};
+        assertTrue(rb.appendBuffer(data2));
+        assertEquals(2, rb.getNumBuffers());
+    }
+
+    @Test
+    public void appendPrunesInFifoOrder() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data1 = {1, 2, 3, 4, 5};
+        final byte[] data2 = {6, 7, 8, 9, 10};
+        assertTrue(rb.appendBuffer(data1));
+        assertTrue(rb.appendBuffer(data2));
+
+        final byte[] data3 = {11};
+        assertTrue(rb.appendBuffer(data3));
+        assertEquals(2, rb.getNumBuffers());
+        assertSame(data2, rb.getBuffer(0));
+        assertSame(data3, rb.getBuffer(1));
+    }
+
+    @Test
+    public void appendPrunesEvenWhenNewDataCanNotFit() {
+        final ByteArrayRingBuffer rb = new ByteArrayRingBuffer(MAX_BYTES);
+        final byte[] data1 = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+        assertTrue(rb.appendBuffer(data1));
+
+        final byte[] data2 = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};
+        assertFalse(rb.appendBuffer(data2));
+        assertEquals(0, rb.getNumBuffers());
+    }
+}