From f10820769836b265266c75763ebbd798bd52db09 Mon Sep 17 00:00:00 2001
From: John Hurliman <jhurliman@jhurliman.org>
Date: Fri, 25 Jun 2010 01:24:11 +0000
Subject: [PATCH] * Fixed a bug in BitPack where existing 1 bits were not being
 overwritten by new 0 bits * Added BitPack.PackBit() * Made Binary LLSD
 deserialization more lenient when parsing the header. Tests pass again

git-svn-id: http://libopenmetaverse.googlecode.com/svn/libopenmetaverse/trunk@3364 52acb1d6-8a22-11de-b505-999d5b087335
---
 .../LLSD/BinaryLLSD.cs                        |  8 +++++---
 OpenMetaverse.Tests/BinaryLLSDTests.cs        |  2 +-
 OpenMetaverse.Tests/TypeTests.cs              | 16 +++++++++++++++
 OpenMetaverse/BitPack.cs                      | 20 ++++++++++++++++++-
 4 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/OpenMetaverse.StructuredData/LLSD/BinaryLLSD.cs b/OpenMetaverse.StructuredData/LLSD/BinaryLLSD.cs
index a3a17fff..9d1096ef 100644
--- a/OpenMetaverse.StructuredData/LLSD/BinaryLLSD.cs
+++ b/OpenMetaverse.StructuredData/LLSD/BinaryLLSD.cs
@@ -53,7 +53,8 @@ namespace OpenMetaverse.StructuredData
         private const int int32Length = 4;
         private const int doubleLength = 8;
 
-        private const string llsdBinaryHead = "<? llsd/binary ?>\n";
+        private const string llsdBinaryHead = "<? llsd/binary ?>";
+        private const string llsdBinaryHead2 = "<?llsd/binary?>";
         private const byte undefBinaryValue = (byte)'!';
         private const byte trueBinaryValue = (byte)'1';
         private const byte falseBinaryValue = (byte)'0';
@@ -98,10 +99,11 @@ namespace OpenMetaverse.StructuredData
 
             SkipWhiteSpace(stream);
 
-            bool result = FindString(stream, llsdBinaryHead);
-            if (!result)
+            if (!FindString(stream, llsdBinaryHead) && !FindString(stream, llsdBinaryHead2))
                 throw new OSDException("Failed to decode binary LLSD");
 
+            SkipWhiteSpace(stream);
+
             return ParseLLSDBinaryElement(stream);
         }
 
diff --git a/OpenMetaverse.Tests/BinaryLLSDTests.cs b/OpenMetaverse.Tests/BinaryLLSDTests.cs
index 59db9091..185d6686 100644
--- a/OpenMetaverse.Tests/BinaryLLSDTests.cs
+++ b/OpenMetaverse.Tests/BinaryLLSDTests.cs
@@ -49,7 +49,7 @@ namespace OpenMetaverse.Tests
     [TestFixture()]
     public class BinarySDTests
     {
-        private static byte[] binaryHead = { 0x3c, 0x3f, 0x6c, 0x6c, 0x73, 0x64, 0x2f, 0x62, 0x69, 0x6e, 0x61, 0x72, 0x79, 0x3f, 0x3e, 0xa };
+        private static readonly byte[] binaryHead = Encoding.ASCII.GetBytes("<? llsd/binary ?>");
 
         [Test()]
         public void HelperFunctions()
diff --git a/OpenMetaverse.Tests/TypeTests.cs b/OpenMetaverse.Tests/TypeTests.cs
index 0622e678..1819eea8 100644
--- a/OpenMetaverse.Tests/TypeTests.cs
+++ b/OpenMetaverse.Tests/TypeTests.cs
@@ -194,6 +194,22 @@ namespace OpenMetaverse.Tests
 
             b = bitpacker.UnpackBits(16);
             Assert.IsTrue(b == 1000, "Unpacked " + b + " instead of 1000");
+
+            packedBytes = new byte[1];
+            bitpacker = new BitPack(packedBytes, 0);
+            bitpacker.PackBit(true);
+
+            bitpacker = new BitPack(packedBytes, 0);
+            b = bitpacker.UnpackBits(1);
+            Assert.IsTrue(b == 1, "Unpacked " + b + " instead of 1");
+
+            packedBytes = new byte[1] { Byte.MaxValue };
+            bitpacker = new BitPack(packedBytes, 0);
+            bitpacker.PackBit(false);
+
+            bitpacker = new BitPack(packedBytes, 0);
+            b = bitpacker.UnpackBits(1);
+            Assert.IsTrue(b == 0, "Unpacked " + b + " instead of 0");
         }
 
         [Test]
diff --git a/OpenMetaverse/BitPack.cs b/OpenMetaverse/BitPack.cs
index fc1079b3..c1f5ac67 100644
--- a/OpenMetaverse/BitPack.cs
+++ b/OpenMetaverse/BitPack.cs
@@ -55,6 +55,8 @@ namespace OpenMetaverse
 
 
         private const int MAX_BITS = 8;
+        private static readonly byte[] ON = new byte[] { 1 };
+        private static readonly byte[] OFF = new byte[] { 0 };
 
         private int bytePos;
         private int bitPos;
@@ -108,6 +110,18 @@ namespace OpenMetaverse
             PackBitArray(input, totalCount);
         }
 
+        /// <summary>
+        /// Pack a single bit in to the data
+        /// </summary>
+        /// <param name="bit">Bit to pack</param>
+        public void PackBit(bool bit)
+        {
+            if (bit)
+                PackBitArray(ON, 1);
+            else
+                PackBitArray(OFF, 1);
+        }
+
         /// <summary>
         /// 
         /// </summary>
@@ -327,8 +341,12 @@ namespace OpenMetaverse
 
                 while (count > 0)
                 {
+                    byte curBit = (byte)(0x80 >> bitPos);
+
                     if ((data[curBytePos] & (0x01 << (count - 1))) != 0)
-                        Data[bytePos] |= (byte)(0x80 >> bitPos);
+                        Data[bytePos] |= curBit;
+                    else
+                        Data[bytePos] &= (byte)~curBit;
 
                     --count;
                     ++bitPos;