cuetools flac encoder: was producing corrupt seek table that caused

fb2k to crash while seeking.

CUETools/CUETools.TestCodecs/BitWriterTest.cs

@@ -0,0 +1,106 @@
+using CUETools.Codecs;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+
+namespace CUETools.TestCodecs
+{
+    
+    
+    /// <summary>
+    ///This is a test class for BitWriterTest and is intended
+    ///to contain all BitWriterTest Unit Tests
+    ///</summary>
+    [TestClass()]
+    public class BitWriterTest
+    {
+
+
+        private TestContext testContextInstance;
+
+        /// <summary>
+        ///Gets or sets the test context which provides
+        ///information about and functionality for the current test run.
+        ///</summary>
+        public TestContext TestContext
+        {
+            get
+            {
+                return testContextInstance;
+            }
+            set
+            {
+                testContextInstance = value;
+            }
+        }
+
+        #region Additional test attributes
+        // 
+        //You can use the following additional attributes as you write your tests:
+        //
+        //Use ClassInitialize to run code before running the first test in the class
+        //[ClassInitialize()]
+        //public static void MyClassInitialize(TestContext testContext)
+        //{
+        //}
+        //
+        //Use ClassCleanup to run code after all tests in a class have run
+        //[ClassCleanup()]
+        //public static void MyClassCleanup()
+        //{
+        //}
+        //
+        //Use TestInitialize to run code before running each test
+        //[TestInitialize()]
+        //public void MyTestInitialize()
+        //{
+        //}
+        //
+        //Use TestCleanup to run code after each test has run
+        //[TestCleanup()]
+        //public void MyTestCleanup()
+        //{
+        //}
+        //
+        #endregion
+
+
+        /// <summary>
+        ///A test for writebits
+        ///</summary>
+        [TestMethod()]
+        public void writebitsTest()
+        {
+            byte[] buf = new byte[0x10000];
+            for (int seed = 0; seed < 10; seed++)
+            {
+                BitWriter target = new BitWriter(buf, 0, buf.Length);
+                var rnd = new Random(seed);
+                int count = 0;
+                do
+                {
+                    int bits = rnd.Next(0, 64) + 1;
+                    ulong val = (1U << (bits - 1));
+                    target.writebits(bits, val);
+                    count++;
+                }
+                while (target.Length < buf.Length - 32);
+                target.flush();
+                rnd = new Random(seed);
+                unsafe
+                {
+                    fixed (byte* ptr = buf)
+                    {
+                        BitReader reader = new BitReader(ptr, 0, buf.Length);
+                        for (int i = 0; i < count; i++)
+                        {
+                            int bits = rnd.Next(0, 64) + 1;
+                            ulong val = (1U << (bits - 1));
+                            ulong val1 = reader.readbits64(bits);
+                            Assert.AreEqual(val, val1, string.Format("i = {0}, bits = {1}, seed = {2}, pos = {3}", i, bits, seed, reader.Position));
+                        }
+                    }
+                }
+            }
+        }
+    }
+}