Add Package.RenameFile, lowercase paths like Valve and fix writes that corrupt or truncate VPKs

ValvePak/ValvePak.Test/MultiChunkWriteTest.cs

@@ -34,13 +34,13 @@ public async Task WriteMultiChunkPackage()
 			using (var package = new Package())
 			{
 				package.SetFileName(dirPath);
-				package.WriteChunkSize = 1024;
+				package.WriteChunkSize = 800;
 
 				for (var i = 0; i < 10; i++)
 				{
 					var entry = package.AddFile($"files/chunked_{i}.bin", CreateTestData(400, (byte)i), multiChunk: true);
 
-					// 400 byte files with a 1024 chunk size, so three files per chunk
+					// 400 byte files with an 800 byte chunk size: a chunk file at exactly 800 bytes is not full yet, so each one holds three files
 					await Assert.That(entry.ArchiveIndex).IsEqualTo((ushort)(i / 3));
 				}
 
@@ -274,17 +274,17 @@ public async Task AddFileThrowsWhenExceedingChunkLimit()
 			package.SetFileName(TempPath("limit_dir.vpk"));
 			package.WriteChunkSize = 1;
 
-			// With a chunk size of 1 every file starts a new chunk
+			// With a chunk size of 1 every file of 2 bytes starts a new chunk
 			PackageEntry? entry = null;
 
 			for (var i = 0; i < 0x7FFF; i++)
 			{
-				entry = package.AddFile($"{i}.bin", [1], multiChunk: true);
+				entry = package.AddFile($"{i}.bin", [1, 2], multiChunk: true);
 			}
 
 			await Assert.That(entry!.ArchiveIndex).IsEqualTo((ushort)0x7FFE);
 
-			await Assert.That(() => package.AddFile("one too many.bin", [1], multiChunk: true)).ThrowsExactly<InvalidOperationException>()
+			await Assert.That(() => package.AddFile("one too many.bin", [1, 2], multiChunk: true)).ThrowsExactly<InvalidOperationException>()
 				.WithMessageContaining("maximum amount of chunk files", StringComparison.Ordinal);
 		}
 
@@ -492,7 +492,7 @@ public async Task WritesAgainAfterAddingMoreFiles()
 		public async Task WriteChunkSizeValidation()
 		{
 			using var package = new Package();
-			await Assert.That(package.WriteChunkSize).IsEqualTo(200 * 1024 * 1024);
+			await Assert.That(package.WriteChunkSize).IsEqualTo(100 * 1024 * 1024);
 			await Assert.That(() => package.WriteChunkSize = 0).ThrowsExactly<ArgumentOutOfRangeException>();
 			await Assert.That(() => package.WriteChunkSize = -1).ThrowsExactly<ArgumentOutOfRangeException>();
 		}

ValvePak/ValvePak.Test/PackageTest.cs

@@ -524,6 +524,44 @@ public async Task InvalidWholeFileChecksumThrows()
 			await Assert.That(() => package.VerifyHashes()).ThrowsExactly<InvalidDataException>();
 		}
 
+		[Test]
+		[Arguments(0, "File tree")]
+		[Arguments(16, "Archive MD5 entries")]
+		public async Task SectionChecksumMismatchIsReportedWhenWholeFileChecksumMatches(int checksumOffset, string sectionName)
+		{
+			var data = CreateSmallPackageBytes();
+			var otherMD5SectionOffset = GetOtherMD5SectionOffset(data);
+
+			data.AsSpan(otherMD5SectionOffset + checksumOffset, 16).Fill(0xAB);
+			MD5.HashData(data.AsSpan(0, otherMD5SectionOffset + 32)).CopyTo(data, otherMD5SectionOffset + 32);
+
+			using var package = new Package();
+			package.SetFileName("a.vpk");
+			package.Read(new MemoryStream(data));
+
+			var progress = new SynchronousProgress();
+
+			await Assert.That(() => package.VerifyHashes(progress)).ThrowsNothing();
+			await Assert.That(progress.Reports).Count().IsEqualTo(1);
+			await Assert.That(progress.Reports[0]).StartsWith($"{sectionName} checksum mismatch (", StringComparison.Ordinal);
+		}
+
+		[Test]
+		public async Task SectionChecksumMismatchThrowsWhenWholeFileChecksumMismatches()
+		{
+			var data = CreateSmallPackageBytes();
+			var otherMD5SectionOffset = GetOtherMD5SectionOffset(data);
+
+			data.AsSpan(otherMD5SectionOffset, 16).Fill(0xAB);
+
+			using var package = new Package();
+			package.SetFileName("a.vpk");
+			package.Read(new MemoryStream(data));
+
+			await Assert.That(() => package.VerifyHashes()).ThrowsExactly<InvalidDataException>()
+				.WithMessageContaining("File tree checksum mismatch", StringComparison.Ordinal);
+		}
+
 		[Test]
 		public async Task InvalidSignatureFails()
 		{
@@ -629,7 +667,7 @@ public async Task ThrowsWhenReadTwice()
 		}
 
 		[Test]
-		public async Task VerifyHashesThrowsOnVersion1()
+		public async Task VerifyHashesSkipsVersion1()
 		{
 			using var package = new Package();
 			package.SetFileName("a.vpk");
@@ -638,8 +676,10 @@ public async Task VerifyHashesThrowsOnVersion1()
 			using var ms = new MemoryStream([0x34, 0x12, 0xAA, 0x55, 0x01, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00]);
 			package.Read(ms);
 
-			await Assert.That(() => package.VerifyHashes()).ThrowsExactly<InvalidDataException>()
-				.WithMessage("Only version 2 is supported.", StringComparison.Ordinal);
+			var progress = new SynchronousProgress();
+
+			await Assert.That(() => package.VerifyHashes(progress)).ThrowsNothing();
+			await Assert.That(progress.Reports).IsEquivalentTo(["Version 1 packages have no checksums to verify."]);
 		}
 
 		[Test]
@@ -870,8 +910,10 @@ public async Task ThrowsOnDirectoryTreeEndingInTheMiddleOfString(string tree)
 		}
 
 		private const int TreeSizeOffset = 8;
+		private const int FileDataSectionSizeOffset = 12;
 		private const int ArchiveMD5SectionSizeOffset = 16;
 		private const int SignatureSectionSizeOffset = 24;
+		private const int HeaderSize = 28;
 		private const int EmbeddedPrefixLength = 1000;
 		private const int EmbeddedSuffixLength = 50;
 
@@ -886,6 +928,16 @@ private static byte[] CreateSmallPackageBytes()
 			return output.ToArray();
 		}
 
+		private static int GetOtherMD5SectionOffset(byte[] package)
+		{
+			var span = package.AsSpan();
+			var treeSize = BinaryPrimitives.ReadInt32LittleEndian(span[TreeSizeOffset..]);
+			var fileDataSectionSize = BinaryPrimitives.ReadInt32LittleEndian(span[FileDataSectionSizeOffset..]);
+			var archiveMD5SectionSize = BinaryPrimitives.ReadInt32LittleEndian(span[ArchiveMD5SectionSizeOffset..]);
+
+			return HeaderSize + treeSize + fileDataSectionSize + archiveMD5SectionSize;
+		}
+
 		/// <summary>
 		/// Creates a package whose signature section holds the given little-endian integers.
 		/// </summary>

ValvePak/ValvePak.Test/WriteTest.cs

@@ -35,9 +35,7 @@ public async Task CreateNewPackage()
 			output.Position = 0;
 
 			// Verify
-			using var packageWritten = new Package();
-			packageWritten.SetFileName("test.vpk");
-			packageWritten.Read(output);
+			using var packageWritten = ReadBack(output);
 			packageWritten.VerifyHashes();
 
 			var newEntry = packageWritten.FindEntry(newName);
@@ -76,9 +74,7 @@ public async Task WriteManyFiles()
 			output.Position = 0;
 
 			// Verify
-			using var packageWritten = new Package();
-			packageWritten.SetFileName("test.vpk");
-			packageWritten.Read(output);
+			using var packageWritten = ReadBack(output);
 			packageWritten.VerifyHashes();
 
 			await Assert.That(packageWritten.Entries!["txt"]).Count().IsEqualTo(1000);
@@ -118,22 +114,16 @@ await Assert.That(package.RemoveFile(new PackageEntry
 		public async Task SetsSpaces()
 		{
 			using var package = new Package();
-			var file = package.AddFile("", []);
-			using (Assert.Multiple())
-			{
-				await Assert.That(file.TypeName).IsEqualTo(" ");
-				await Assert.That(file.DirectoryName).IsEqualTo(" ");
-				await Assert.That(file.FileName).IsEqualTo("");
-				await Assert.That(package.Entries!.ContainsKey(" ")).IsTrue();
-				await Assert.That(package.Entries[" "][0]).IsEqualTo(file);
-			}
+			await Assert.That(() => package.AddFile("", [])).ThrowsExactly<ArgumentException>();
 
 			var file2 = package.AddFile("hello", []);
 			using (Assert.Multiple())
 			{
 				await Assert.That(file2.TypeName).IsEqualTo(" ");
 				await Assert.That(file2.DirectoryName).IsEqualTo(" ");
 				await Assert.That(file2.FileName).IsEqualTo("hello");
+				await Assert.That(package.Entries!.ContainsKey(" ")).IsTrue();
+				await Assert.That(package.Entries[" "][0]).IsEqualTo(file2);
 			}
 
 			var file3 = package.AddFile("hello.txt", []);
@@ -194,9 +184,7 @@ public async Task WritesToNonSeekableStream(uint version)
 			}
 
 			using var output = new MemoryStream(nonSeekable.ToArray());
-			using var readBack = new Package();
-			readBack.SetFileName("test.vpk");
-			readBack.Read(output);
+			using var readBack = ReadBack(output);
 
 			if (version >= 2)
 			{
@@ -259,9 +247,7 @@ public async Task WriteAndVerifyRoundTrip()
 
 			output.Position = 0;
 
-			using var readBack = new Package();
-			readBack.SetFileName("test.vpk");
-			readBack.Read(output);
+			using var readBack = ReadBack(output);
 
 			using (Assert.Multiple())
 			{
@@ -292,9 +278,7 @@ public async Task WriteVersion1Package()
 
 			output.Position = 0;
 
-			using var readBack = new Package();
-			readBack.SetFileName("test.vpk");
-			readBack.Read(output);
+			using var readBack = ReadBack(output);
 
 			using (Assert.Multiple())
 			{
@@ -327,18 +311,14 @@ public async Task WritePreservesVersionOfReadPackage()
 
 			output.Position = 0;
 
-			using var readBack = new Package();
-			readBack.SetFileName("test.vpk");
-			readBack.Read(output);
+			using var readBack = ReadBack(output);
 
 			using var output2 = new MemoryStream();
 			readBack.Write(output2);
 
 			output2.Position = 0;
 
-			using var readBack2 = new Package();
-			readBack2.SetFileName("test.vpk");
-			readBack2.Read(output2);
+			using var readBack2 = ReadBack(output2);
 
 			await Assert.That(readBack2.Version).IsEqualTo(1u);
 
@@ -428,9 +408,7 @@ public async Task WriteIntoLongerStream(int position, uint version)
 
 			output.Position = position;
 
-			using var readBack = new Package();
-			readBack.SetFileName("test.vpk");
-			readBack.Read(output);
+			using var readBack = ReadBack(output);
 
 			await Assert.That(readBack.Version).IsEqualTo(version);
 
@@ -517,6 +495,35 @@ public async Task AddedFilesCanBeFoundAfterOptimizingForBinarySearch(StringCompa
 			await Assert.That(package.FindEntry("addons/chess/missing.vdf")).IsNull();
 		}
 
+		[Test]
+		public async Task RenameFile()
+		{
+			using var package = new Package();
+			package.OptimizeEntriesForBinarySearch(StringComparison.OrdinalIgnoreCase);
+			var entry = package.AddFile("kitten.jpg", Encoding.UTF8.GetBytes("meow"));
+			package.AddFile("other.txt", []);
+
+			package.RenameFile(entry, "/Path\\To/Cat.PNG");
+
+			using (Assert.Multiple())
+			{
+				await Assert.That(entry.GetFullPath()).IsEqualTo("path/to/cat.png");
+				await Assert.That(package.FindEntry("kitten.jpg")).IsNull();
+				await Assert.That(package.FindEntry("path/to/cat.png")).IsEqualTo(entry);
+				await Assert.That(package.Entries!.ContainsKey("jpg")).IsFalse();
+				await Assert.That(() => package.RenameFile(entry, "other.txt")).ThrowsExactly<ArgumentException>();
+			}
+		}
+
+		private static Package ReadBack(Stream stream)
+		{
+			var package = new Package();
+			package.SetFileName("test.vpk");
+			package.Read(stream);
+
+			return package;
+		}
+
 		/// <summary>
 		/// Write only stream that can not seek, collecting the written bytes.
 		/// </summary>

ValvePak/ValvePak/Archive.cs

@@ -25,6 +25,11 @@ protected Archive(long origin, long dataOffset)
 		/// </summary>
 		protected long Origin { get; }
 
+		/// <summary>
+		/// Gets the size in bytes of the archive.
+		/// </summary>
+		public abstract long Length { get; }
+
 		/// <summary>
 		/// Reads data at the given offset until the output is full or the end of the archive is reached.
 		/// This method is safe to call from multiple threads.

ValvePak/ValvePak/FileArchive.cs

@@ -25,6 +25,8 @@ public FileArchive(SafeFileHandle handle, bool ownsHandle, long origin, long dat
 			OwnsHandle = ownsHandle;
 		}
 
+		public override long Length => RandomAccess.GetLength(Handle) - Origin;
+
 		public override int Read(long offset, Span<byte> output)
 		{
 			var totalRead = 0;