PR #455: Add FastZip.CreateZip with a leaveOpen parameter

* Add a variant of FastZip.CreateZip with a leaveOpen parameter to control output stream disposal
* Add unit test for FastZip.CreateZip leaving the stream open or disposed as required

Author: Numpsy

src/ICSharpCode.SharpZipLib/Zip/FastZip.cs

@@ -361,13 +361,28 @@ public void CreateZip(string zipFileName, string sourceDirectory, bool recurse,
 		/// <param name="directoryFilter">The <see cref="PathFilter">directory filter</see> to apply.</param>
 		/// <remarks>The <paramref name="outputStream"/> is closed after creation.</remarks>
 		public void CreateZip(Stream outputStream, string sourceDirectory, bool recurse, string fileFilter, string directoryFilter)
+		{
+			CreateZip(outputStream, sourceDirectory, recurse, fileFilter, directoryFilter, false);
+		}
+
+		/// <summary>
+		/// Create a zip archive sending output to the <paramref name="outputStream"/> passed.
+		/// </summary>
+		/// <param name="outputStream">The stream to write archive data to.</param>
+		/// <param name="sourceDirectory">The directory to source files from.</param>
+		/// <param name="recurse">True to recurse directories, false for no recursion.</param>
+		/// <param name="fileFilter">The <see cref="PathFilter">file filter</see> to apply.</param>
+		/// <param name="directoryFilter">The <see cref="PathFilter">directory filter</see> to apply.</param>
+		/// <param name="leaveOpen">true to leave <paramref name="outputStream"/> open after the zip has been created, false to dispose it.</param>
+		public void CreateZip(Stream outputStream, string sourceDirectory, bool recurse, string fileFilter, string directoryFilter, bool leaveOpen)
 		{
 			NameTransform = new ZipNameTransform(sourceDirectory);
 			sourceDirectory_ = sourceDirectory;
 
 			using (outputStream_ = new ZipOutputStream(outputStream))
 			{
 				outputStream_.SetLevel((int)CompressionLevel);
+				outputStream_.IsStreamOwner = !leaveOpen;
 
 				if (password_ != null)
 				{

test/ICSharpCode.SharpZipLib.Tests/Zip/FastZipHandling.cs

@@ -625,5 +625,45 @@ public void SetDirectoryModifiedDate()
 				Directory.Delete(targetDir, true);
 			}
 		}
+
+		/// <summary>
+		/// Test for https://github.com/icsharpcode/SharpZipLib/issues/78
+		/// </summary>
+		/// <param name="leaveOpen">if true, the stream given to CreateZip should be left open, if false it should be disposed.</param>
+		[TestCase(true)]
+		[TestCase(false)]
+		[Category("Zip")]
+		[Category("CreatesTempFile")]
+		public void CreateZipShouldLeaveOutputStreamOpenIfRequested(bool leaveOpen)
+		{
+			const string tempFileName = "a(2).dat";
+
+			using (var tempFolder = new Utils.TempDir())
+			{
+				// Create test input file
+				string addFile = Path.Combine(tempFolder.Fullpath, tempFileName);
+				MakeTempFile(addFile, 16);
+
+				// Create the zip with fast zip
+				var target = new TrackedMemoryStream();
+				var fastZip = new FastZip();
+
+     			fastZip.CreateZip(target, tempFolder.Fullpath, false, @"a\(2\)\.dat", null, leaveOpen: leaveOpen);
+
+				// Check that the output stream was disposed (or not) as expected
+				Assert.That(target.IsDisposed, Is.Not.EqualTo(leaveOpen), "IsDisposed should be the opposite of leaveOpen");
+
+				// Check that the file contents are correct in both cases
+				var archive = new MemoryStream(target.ToArray());
+				using (ZipFile zf = new ZipFile(archive))
+				{
+					Assert.AreEqual(1, zf.Count);
+					ZipEntry entry = zf[0];
+					Assert.AreEqual(tempFileName, entry.Name);
+					Assert.AreEqual(16, entry.Size);
+					Assert.IsTrue(zf.TestArchive(true));
+				}
+			}
+		}
 	}
 }