content: // Protocol Buffers - Google's data interchange format
  // Copyright 2008 Google Inc.  All rights reserved.
  // http://code.google.com/p/protobuf/
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  package com.google.protobuf.test;
  import com.google.protobuf.*;
  
  import protobuf_unittest.UnittestProto.TestAllTypes;
  import protobuf_unittest.UnittestProto.TestRecursiveMessage;
  
  import junit.framework.TestCase;
  
  import java.io.ByteArrayInputStream;
  import java.io.FilterInputStream;
  import java.io.InputStream;
  import java.io.IOException;
  
  /**
   * Unit test for {@link CodedInputStream}.
   *
   * @author kenton@google.com Kenton Varda
   */
  public class CodedInputStreamTest extends TestCase {
    /**
     * Helper to construct a byte array from a bunch of bytes.  The inputs are
     * actually ints so that I can use hex notation and not get stupid errors
     * about precision.
     */
    private byte[] bytes(int... bytesAsInts) {
      byte[] bytes = new byte[bytesAsInts.length];
      for (int i = 0; i < bytesAsInts.length; i++) {
        bytes[i] = (byte) bytesAsInts[i];
      }
      return bytes;
    }
  
    /**
     * An InputStream which limits the number of bytes it reads at a time.
     * We use this to make sure that CodedInputStream doesn't screw up when
     * reading in small blocks.
     */
    private static final class SmallBlockInputStream extends FilterInputStream {
      private final int blockSize;
  
      public SmallBlockInputStream(byte[] data, int blockSize) {
        this(new ByteArrayInputStream(data), blockSize);
      }
  
      public SmallBlockInputStream(InputStream in, int blockSize) {
        super(in);
        this.blockSize = blockSize;
      }
  
      public int read(byte[] b) throws IOException {
        return super.read(b, 0, Math.min(b.length, blockSize));
      }
  
      public int read(byte[] b, int off, int len) throws IOException {
        return super.read(b, off, Math.min(len, blockSize));
      }
    }
  
    /**
     * Parses the given bytes using readRawVarint32() and readRawVarint64() and
     * checks that the result matches the given value.
     */
    private void assertReadVarint(byte[] data, long value) throws Exception {
      CodedInputStream input = CodedInputStream.newInstance(data);
      assertEquals((int)value, input.readRawVarint32());
  
      input = CodedInputStream.newInstance(data);
      assertEquals(value, input.readRawVarint64());
      assertTrue(input.isAtEnd());
  
      // Try different block sizes.
      for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
        input = CodedInputStream.newInstance(
          new SmallBlockInputStream(data, blockSize));
        assertEquals((int)value, input.readRawVarint32());
  
        input = CodedInputStream.newInstance(
          new SmallBlockInputStream(data, blockSize));
        assertEquals(value, input.readRawVarint64());
        assertTrue(input.isAtEnd());
      }
  
      // Try reading direct from an InputStream.  We want to verify that it
      // doesn't read past the end of the input, so we copy to a new, bigger
      // array first.
      byte[] longerData = new byte[data.length + 1];
      System.arraycopy(data, 0, longerData, 0, data.length);
      InputStream rawInput = new ByteArrayInputStream(longerData);
    }
  
    /**
     * Parses the given bytes using readRawVarint32() and readRawVarint64() and
     * expects them to fail with an InvalidProtocolBufferException whose
     * description matches the given one.
     */
    private void assertReadVarintFailure(
        InvalidProtocolBufferException expected, byte[] data)
        throws Exception {
      CodedInputStream input = CodedInputStream.newInstance(data);
      try {
        input.readRawVarint32();
        fail("Should have thrown an exception.");
      } catch (InvalidProtocolBufferException e) {
        assertEquals(expected.getMessage(), e.getMessage());
      }
  
      input = CodedInputStream.newInstance(data);
      try {
        input.readRawVarint64();
        fail("Should have thrown an exception.");
      } catch (InvalidProtocolBufferException e) {
        assertEquals(expected.getMessage(), e.getMessage());
      }
    }
  
    /** Tests readRawVarint32() and readRawVarint64(). */
    public void testReadVarint() throws Exception {
      assertReadVarint(bytes(0x00), 0);
      assertReadVarint(bytes(0x01), 1);
      assertReadVarint(bytes(0x7f), 127);
      // 14882
      assertReadVarint(bytes(0xa2, 0x74), (0x22 << 0) | (0x74 << 7));
      // 2961488830
      assertReadVarint(bytes(0xbe, 0xf7, 0x92, 0x84, 0x0b),
        (0x3e << 0) | (0x77 << 7) | (0x12 << 14) | (0x04 << 21) |
        (0x0bL << 28));
  
      // 64-bit
      // 7256456126
      assertReadVarint(bytes(0xbe, 0xf7, 0x92, 0x84, 0x1b),
        (0x3e << 0) | (0x77 << 7) | (0x12 << 14) | (0x04 << 21) |
        (0x1bL << 28));
      // 41256202580718336
      assertReadVarint(
        bytes(0x80, 0xe6, 0xeb, 0x9c, 0xc3, 0xc9, 0xa4, 0x49),
        (0x00 << 0) | (0x66 << 7) | (0x6b << 14) | (0x1c << 21) |
        (0x43L << 28) | (0x49L << 35) | (0x24L << 42) | (0x49L << 49));
      // 11964378330978735131
      assertReadVarint(
        bytes(0x9b, 0xa8, 0xf9, 0xc2, 0xbb, 0xd6, 0x80, 0x85, 0xa6, 0x01),
        (0x1b << 0) | (0x28 << 7) | (0x79 << 14) | (0x42 << 21) |
        (0x3bL << 28) | (0x56L << 35) | (0x00L << 42) |
        (0x05L << 49) | (0x26L << 56) | (0x01L << 63));
    }
  
    /**
     * Parses the given bytes using readRawLittleEndian32() and checks
     * that the result matches the given value.
     */
    private void assertReadLittleEndian32(byte[] data, int value)
                                          throws Exception {
      CodedInputStream input = CodedInputStream.newInstance(data);
      assertEquals(value, input.readRawLittleEndian32());
      assertTrue(input.isAtEnd());
  
      // Try different block sizes.
      for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
        input = CodedInputStream.newInstance(
          new SmallBlockInputStream(data, blockSize));
        assertEquals(value, input.readRawLittleEndian32());
        assertTrue(input.isAtEnd());
      }
    }
  
    /**
     * Parses the given bytes using readRawLittleEndian64() and checks
     * that the result matches the given value.
     */
    private void assertReadLittleEndian64(byte[] data, long value)
                                          throws Exception {
      CodedInputStream input = CodedInputStream.newInstance(data);
      assertEquals(value, input.readRawLittleEndian64());
      assertTrue(input.isAtEnd());
  
      // Try different block sizes.
      for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
        input = CodedInputStream.newInstance(
          new SmallBlockInputStream(data, blockSize));
        assertEquals(value, input.readRawLittleEndian64());
        assertTrue(input.isAtEnd());
      }
    }
  
    /** Tests readRawLittleEndian32() and readRawLittleEndian64(). */
    public void testReadLittleEndian() throws Exception {
      assertReadLittleEndian32(bytes(0x78, 0x56, 0x34, 0x12), 0x12345678);
      assertReadLittleEndian32(bytes(0xf0, 0xde, 0xbc, 0x9a), 0x9abcdef0);
  
      assertReadLittleEndian64(
        bytes(0xf0, 0xde, 0xbc, 0x9a, 0x78, 0x56, 0x34, 0x12),
        0x123456789abcdef0L);
      assertReadLittleEndian64(
        bytes(0x78, 0x56, 0x34, 0x12, 0xf0, 0xde, 0xbc, 0x9a),
        0x9abcdef012345678L);
    }
  
    /** Test decodeZigZag32() and decodeZigZag64(). */
    public void testDecodeZigZag() throws Exception {
      assertEquals( 0, CodedInputStream.decodeZigZag32(0));
      assertEquals(-1, CodedInputStream.decodeZigZag32(1));
      assertEquals( 1, CodedInputStream.decodeZigZag32(2));
      assertEquals(-2, CodedInputStream.decodeZigZag32(3));
      assertEquals(0x3FFFFFFF, CodedInputStream.decodeZigZag32(0x7FFFFFFE));
      assertEquals(0xC0000000, CodedInputStream.decodeZigZag32(0x7FFFFFFF));
      assertEquals(0x7FFFFFFF, CodedInputStream.decodeZigZag32(0xFFFFFFFE));
      assertEquals(0x80000000, CodedInputStream.decodeZigZag32(0xFFFFFFFF));
  
      assertEquals( 0, CodedInputStream.decodeZigZag64(0));
      assertEquals(-1, CodedInputStream.decodeZigZag64(1));
      assertEquals( 1, CodedInputStream.decodeZigZag64(2));
      assertEquals(-2, CodedInputStream.decodeZigZag64(3));
      assertEquals(0x000000003FFFFFFFL,
                   CodedInputStream.decodeZigZag64(0x000000007FFFFFFEL));
      assertEquals(0xFFFFFFFFC0000000L,
                   CodedInputStream.decodeZigZag64(0x000000007FFFFFFFL));
      assertEquals(0x000000007FFFFFFFL,
                   CodedInputStream.decodeZigZag64(0x00000000FFFFFFFEL));
      assertEquals(0xFFFFFFFF80000000L,
                   CodedInputStream.decodeZigZag64(0x00000000FFFFFFFFL));
      assertEquals(0x7FFFFFFFFFFFFFFFL,
                   CodedInputStream.decodeZigZag64(0xFFFFFFFFFFFFFFFEL));
      assertEquals(0x8000000000000000L,
                   CodedInputStream.decodeZigZag64(0xFFFFFFFFFFFFFFFFL));
    }
  
    /** Tests reading and parsing a whole message with every field type. */
    public void testReadWholeMessage() throws Exception {
      TestAllTypes message = TestUtil.getAllSet();
  
      byte[] rawBytes = message.toByteArray();
      assertEquals(rawBytes.length, message.getSerializedSize());
  
      TestAllTypes message2 = TestAllTypes.parseFrom(rawBytes);
      TestUtil.assertAllFieldsSet(message2);
  
      // Try different block sizes.
      for (int blockSize = 1; blockSize < 256; blockSize *= 2) {
        message2 = TestAllTypes.parseFrom(
          new SmallBlockInputStream(rawBytes, blockSize));
        TestUtil.assertAllFieldsSet(message2);
      }
    }
  
    /** Tests skipField(). */
    public void testSkipWholeMessage() throws Exception {
      TestAllTypes message = TestUtil.getAllSet();
      byte[] rawBytes = message.toByteArray();
  
      // Create two parallel inputs.  Parse one as unknown fields while using
      // skipField() to skip each field on the other.  Expect the same tags.
      CodedInputStream input1 = CodedInputStream.newInstance(rawBytes);
      CodedInputStream input2 = CodedInputStream.newInstance(rawBytes);
      UnknownFieldSet.Builder unknownFields = UnknownFieldSet.newBuilder();
  
      while (true) {
        int tag = input1.readTag();
        assertEquals(tag, input2.readTag());
        if (tag == 0) {
          break;
        }
        unknownFields.mergeFieldFrom(tag, input1);
        input2.skipField(tag);
      }
    }
  
    /**
     * Test that a bug in skipRawBytes() has been fixed:  if the skip skips
     * exactly up to a limit, this should not break things.
     */
    public void testSkipRawBytesBug() throws Exception {
      byte[] rawBytes = new byte[] { 1, 2 };
      CodedInputStream input = CodedInputStream.newInstance(rawBytes);
  
      int limit = input.pushLimit(1);
      input.skipRawBytes(1);
      input.popLimit(limit);
      assertEquals(2, input.readRawByte());
    }
  
    /**
     * Test that a bug in skipRawBytes() has been fixed:  if the skip skips
     * past the end of a buffer with a limit that has been set past the end of
     * that buffer, this should not break things.
     */
    public void testSkipRawBytesPastEndOfBufferWithLimit() throws Exception {
      byte[] rawBytes = new byte[] { 1, 2, 3, 4, 5 };
      CodedInputStream input = CodedInputStream.newInstance(
          new SmallBlockInputStream(rawBytes, 3));
  
      int limit = input.pushLimit(4);
      // In order to expose the bug we need to read at least one byte to prime the
      // buffer inside the CodedInputStream.
      assertEquals(1, input.readRawByte());
      // Skip to the end of the limit.
      input.skipRawBytes(3);
      assertTrue(input.isAtEnd());
      input.popLimit(limit);
      assertEquals(5, input.readRawByte());
    }
  
    public void testReadHugeBlob() throws Exception {
      // Allocate and initialize a 1MB blob.
      byte[] blob = new byte[1 << 20];
      for (int i = 0; i < blob.length; i++) {
        blob[i] = (byte)i;
      }
  
      // Make a message containing it.
      TestAllTypes.Builder builder = TestAllTypes.newBuilder();
      TestUtil.setAllFields(builder);
      builder.setOptionalBytes(ByteString.copyFrom(blob));
      TestAllTypes message = builder.build();
  
      // Serialize and parse it.  Make sure to parse from an InputStream, not
      // directly from a ByteString, so that CodedInputStream uses buffered
      // reading.
      TestAllTypes message2 =
        TestAllTypes.parseFrom(message.toByteString().newInput());
  
      assertEquals(message.getOptionalBytes(), message2.getOptionalBytes());
  
      // Make sure all the other fields were parsed correctly.
      TestAllTypes message3 = TestAllTypes.newBuilder(message2)
        .setOptionalBytes(TestUtil.getAllSet().getOptionalBytes())
        .build();
      TestUtil.assertAllFieldsSet(message3);
    }
  
    public int makeTag(int number, int tag) {
      return (number << 3) + tag;
    }
  
    public void testReadMaliciouslyLargeBlob() throws Exception {
      ByteString.Output rawOutput = ByteString.newOutput();
      CodedOutputStream output = CodedOutputStream.newInstance(rawOutput);
  
      int tag = makeTag(1, WireFormat.WIRETYPE_LENGTH_DELIMITED);
      output.writeRawVarint32(tag);
      output.writeRawVarint32(0x7FFFFFFF);
      output.writeRawBytes(new byte[32]);  // Pad with a few random bytes.
      output.flush();
  
      CodedInputStream input = rawOutput.toByteString().newCodedInput();
      assertEquals(tag, input.readTag());
  
      try {
        input.readBytes();
        fail("Should have thrown an exception!");
      } catch (InvalidProtocolBufferException e) {
        // success.
      }
    }
  
    private TestRecursiveMessage makeRecursiveMessage(int depth) {
      if (depth == 0) {
        return TestRecursiveMessage.newBuilder().setI(5).build();
      } else {
        return TestRecursiveMessage.newBuilder()
          .setA(makeRecursiveMessage(depth - 1)).build();
      }
    }
  
    private void assertMessageDepth(TestRecursiveMessage message, int depth) {
      if (depth == 0) {
        assertFalse(message.hasA());
        assertEquals(5, message.getI());
      } else {
        assertTrue(message.hasA());
        assertMessageDepth(message.getA(), depth - 1);
      }
    }
  
    public void testResetSizeCounter() throws Exception {
      CodedInputStream input = CodedInputStream.newInstance(
          new SmallBlockInputStream(new byte[256], 8));
      input.setSizeLimit(16);
      input.readRawBytes(16);
      assertEquals(16, input.getTotalBytesRead());
  
      try {
        input.readRawByte();
        fail("Should have thrown an exception!");
      } catch (InvalidProtocolBufferException e) {
        // success.
      }
  
      input.resetSizeCounter();
      assertEquals(0, input.getTotalBytesRead());
      input.readRawByte();  // No exception thrown.
      input.resetSizeCounter();
      assertEquals(0, input.getTotalBytesRead());
    }
  
    /**
     * Tests that if we read an string that contains invalid UTF-8, no exception
     * is thrown.  Instead, the invalid bytes are replaced with the Unicode
     * "replacement character" U+FFFD.
     */
    public void testReadInvalidUtf8() throws Exception {
      ByteString.Output rawOutput = ByteString.newOutput();
      CodedOutputStream output = CodedOutputStream.newInstance(rawOutput);
  
      int tag = makeTag(1, WireFormat.WIRETYPE_LENGTH_DELIMITED);
      output.writeRawVarint32(tag);
      output.writeRawVarint32(1);
      output.writeRawBytes(new byte[] { (byte)0x80 });
      output.flush();
  
      CodedInputStream input = rawOutput.toByteString().newCodedInput();
      assertEquals(tag, input.readTag());
      String text = input.readString();
      assertEquals(0xfffd, text.charAt(0));
    }
  
    public void testReadFromSlice() throws Exception {
      byte[] bytes = bytes(0, 1, 2, 3, 4, 5, 6, 7, 8, 9);
      CodedInputStream in = CodedInputStream.newInstance(bytes, 3, 5);
      assertEquals(0, in.getTotalBytesRead());
      for (int i = 3; i < 8; i++) {
        assertEquals(i, in.readRawByte());
        assertEquals(i-2, in.getTotalBytesRead());
      }
      // eof
      assertEquals(0, in.readTag());
      assertEquals(5, in.getTotalBytesRead());
    }
  
    public void testInvalidTag() throws Exception {
      // Any tag number which corresponds to field number zero is invalid and
      // should throw InvalidProtocolBufferException.
      for (int i = 0; i < 8; i++) {
        try {
          CodedInputStream.newInstance(bytes(i)).readTag();
          fail("Should have thrown an exception.");
        } catch (InvalidProtocolBufferException e) {
        }
      }
    }
  }
  