Rewrite IndirectStorage

build/CodeGen/results.csv

@@ -50,7 +50,14 @@ Module,DescriptionStart,DescriptionEnd,Name,Summary
 
 2,4000,4999,DataCorrupted,
 2,4001,4299,RomCorrupted,
-2,4023,,InvalidIndirectStorageSource,
+
+2,4021,4029,IndirectStorageCorrupted,
+2,4022,,InvalidIndirectEntryOffset,
+2,4023,,InvalidIndirectEntryStorageIndex,
+2,4024,,InvalidIndirectStorageSize,
+2,4025,,InvalidIndirectVirtualOffset,
+2,4026,,InvalidIndirectPhysicalOffset,
+2,4027,,InvalidIndirectStorageIndex,
 
 2,4031,4039,BucketTreeCorrupted,
 2,4032,,InvalidBucketTreeSignature,

src/LibHac/Diag/Assert.cs

@@ -27,5 +27,20 @@ namespace LibHac.Diag
                 throw new LibHacException("Not-null assertion failed.");
             }
         }
+
+        [Conditional("DEBUG")]
+        public static void InRange(int value, int lowerInclusive, int upperExclusive)
+        {
+            InRange((long)value, lowerInclusive, upperExclusive);
+        }
+
+        [Conditional("DEBUG")]
+        public static void InRange(long value, long lowerInclusive, long upperExclusive)
+        {
+            if (value < lowerInclusive || value >= upperExclusive)
+            {
+                throw new LibHacException($"Value {value} is not in the range {lowerInclusive} to {upperExclusive}");
+            }
+        }
     }
 }

src/LibHac/Fs/IStorage.cs

@@ -132,8 +132,8 @@ namespace LibHac.Fs
         protected abstract Result DoRead(long offset, Span<byte> destination);
         protected abstract Result DoWrite(long offset, ReadOnlySpan<byte> source);
         protected abstract Result DoFlush();
-        protected abstract Result DoGetSize(out long size);
         protected abstract Result DoSetSize(long size);
+        protected abstract Result DoGetSize(out long size);
 
         protected virtual Result DoOperateRange(Span<byte> outBuffer, OperationId operationId, long offset, long size,
             ReadOnlySpan<byte> inBuffer)

src/LibHac/Fs/ResultFs.cs

@@ -114,8 +114,20 @@ namespace LibHac.Fs
         public static Result.Base DataCorrupted { [MethodImpl(MethodImplOptions.AggressiveInlining)] get => new Result.Base(ModuleFs, 4000, 4999); }
             /// <summary>Error code: 2002-4001; Range: 4001-4299; Inner value: 0x1f4202</summary>
             public static Result.Base RomCorrupted { [MethodImpl(MethodImplOptions.AggressiveInlining)] get => new Result.Base(ModuleFs, 4001, 4299); }
-                /// <summary>Error code: 2002-4023; Inner value: 0x1f6e02</summary>
-                public static Result.Base InvalidIndirectStorageSource => new Result.Base(ModuleFs, 4023);
+                /// <summary>Error code: 2002-4021; Range: 4021-4029; Inner value: 0x1f6a02</summary>
+                public static Result.Base IndirectStorageCorrupted { [MethodImpl(MethodImplOptions.AggressiveInlining)] get => new Result.Base(ModuleFs, 4021, 4029); }
+                    /// <summary>Error code: 2002-4022; Inner value: 0x1f6c02</summary>
+                    public static Result.Base InvalidIndirectEntryOffset => new Result.Base(ModuleFs, 4022);
+                    /// <summary>Error code: 2002-4023; Inner value: 0x1f6e02</summary>
+                    public static Result.Base InvalidIndirectEntryStorageIndex => new Result.Base(ModuleFs, 4023);
+                    /// <summary>Error code: 2002-4024; Inner value: 0x1f7002</summary>
+                    public static Result.Base InvalidIndirectStorageSize => new Result.Base(ModuleFs, 4024);
+                    /// <summary>Error code: 2002-4025; Inner value: 0x1f7202</summary>
+                    public static Result.Base InvalidIndirectVirtualOffset => new Result.Base(ModuleFs, 4025);
+                    /// <summary>Error code: 2002-4026; Inner value: 0x1f7402</summary>
+                    public static Result.Base InvalidIndirectPhysicalOffset => new Result.Base(ModuleFs, 4026);
+                    /// <summary>Error code: 2002-4027; Inner value: 0x1f7602</summary>
+                    public static Result.Base InvalidIndirectStorageIndex => new Result.Base(ModuleFs, 4027);
 
                 /// <summary>Error code: 2002-4031; Range: 4031-4039; Inner value: 0x1f7e02</summary>
                 public static Result.Base BucketTreeCorrupted { [MethodImpl(MethodImplOptions.AggressiveInlining)] get => new Result.Base(ModuleFs, 4031, 4039); }

src/LibHac/FsSystem/BucketTree2.cs

@@ -105,6 +105,16 @@ namespace LibHac.FsSystem
         public long GetEnd() => EndOffset;
         public long GetSize() => EndOffset - StartOffset;
 
+        public bool Includes(long offset)
+        {
+            return StartOffset <= offset && offset < EndOffset;
+        }
+
+        public bool Includes(long offset, long size)
+        {
+            return size > 0 && StartOffset <= offset && size <= EndOffset - offset;
+        }
+
         public Result Find(ref Visitor visitor, long virtualAddress)
         {
             Assert.AssertTrue(IsInitialized());
@@ -382,6 +392,11 @@ namespace LibHac.FsSystem
                 return Result.Success;
             }
 
+            public void Dispose()
+            {
+                // todo: try using shared arrays
+            }
+
             public bool IsValid() => EntryIndex >= 0;
 
             public bool CanMoveNext()

src/LibHac/FsSystem/IndirectStorage.cs

@@ -1,72 +1,183 @@
 using System;
-using System.Collections.Generic;
-using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using LibHac.Common;
+using LibHac.Diag;
 using LibHac.Fs;
 
 namespace LibHac.FsSystem
 {
     public class IndirectStorage : IStorage
     {
-        private List<RelocationEntry> RelocationEntries { get; }
-        private List<long> RelocationOffsets { get; }
+        public static readonly int StorageCount = 2;
+        public static readonly int NodeSize = 1024 * 16;
 
-        private List<IStorage> Sources { get; } = new List<IStorage>();
-        private BucketTree<RelocationEntry> BucketTree { get; }
-        private long Length { get; }
-        private bool LeaveOpen { get; }
+        private BucketTree2 Table { get; } = new BucketTree2();
+        private SubStorage2[] DataStorage { get; } = new SubStorage2[StorageCount];
 
-        public IndirectStorage(IStorage bucketTreeData, bool leaveOpen, params IStorage[] sources)
+        [StructLayout(LayoutKind.Sequential, Size = 0x14)]
+        public struct Entry
         {
-            Sources.AddRange(sources);
+            private long VirtualOffset;
+            private long PhysicalOffset;
+            public int StorageIndex;
 
-            LeaveOpen = leaveOpen;
+            public void SetVirtualOffset(long offset) => VirtualOffset = offset;
+            public long GetVirtualOffset() => VirtualOffset;
 
-            BucketTree = new BucketTree<RelocationEntry>(bucketTreeData);
-
-            RelocationEntries = BucketTree.GetEntryList();
-            RelocationOffsets = RelocationEntries.Select(x => x.Offset).ToList();
-
-            Length = BucketTree.BucketOffsets.OffsetEnd;
+            public void SetPhysicalOffset(long offset) => PhysicalOffset = offset;
+            public long GetPhysicalOffset() => PhysicalOffset;
         }
 
-        protected override Result DoRead(long offset, Span<byte> destination)
+        public static long QueryHeaderStorageSize() => BucketTree2.QueryHeaderStorageSize();
+
+        public static long QueryNodeStorageSize(int entryCount) =>
+            BucketTree2.QueryNodeStorageSize(NodeSize, Unsafe.SizeOf<Entry>(), entryCount);
+
+        public static long QueryEntryStorageSize(int entryCount) =>
+            BucketTree2.QueryEntryStorageSize(NodeSize, Unsafe.SizeOf<Entry>(), entryCount);
+
+        public bool IsInitialized() => Table.IsInitialized();
+
+        public Result Initialize(SubStorage2 tableStorage)
         {
-            RelocationEntry entry = GetRelocationEntry(offset);
+            // Read and verify the bucket tree header.
+            // note: skip init
+            var header = new BucketTree2.Header();
 
-            if (entry.SourceIndex > Sources.Count)
+            Result rc = tableStorage.Read(0, SpanHelpers.AsByteSpan(ref header));
+            if (rc.IsFailure()) return rc;
+
+            rc = header.Verify();
+            if (rc.IsFailure()) return rc;
+
+            // Determine extents.
+            long nodeStorageSize = QueryNodeStorageSize(header.EntryCount);
+            long entryStorageSize = QueryEntryStorageSize(header.EntryCount);
+            long nodeStorageOffset = QueryHeaderStorageSize();
+            long entryStorageOffset = nodeStorageOffset + nodeStorageSize;
+
+            // Initialize.
+            var nodeStorage = new SubStorage2(tableStorage, nodeStorageOffset, nodeStorageSize);
+            var entryStorage = new SubStorage2(tableStorage, entryStorageOffset, entryStorageSize);
+
+            return Initialize(nodeStorage, entryStorage, header.EntryCount);
+        }
+
+        public Result Initialize(SubStorage2 nodeStorage, SubStorage2 entryStorage, int entryCount)
+        {
+            return Table.Initialize(nodeStorage, entryStorage, NodeSize, Unsafe.SizeOf<Entry>(), entryCount);
+        }
+
+        public void SetStorage(int index, SubStorage2 storage)
+        {
+            Assert.InRange(index, 0, StorageCount);
+            DataStorage[index] = storage;
+        }
+
+        public void SetStorage(int index, IStorage storage, long offset, long size)
+        {
+            Assert.InRange(index, 0, StorageCount);
+            DataStorage[index] = new SubStorage2(storage, offset, size);
+        }
+
+        public Result GetEntryList(Span<Entry> entryBuffer, out int outputEntryCount, long offset, long size)
+        {
+            // Validate pre-conditions
+            Assert.AssertTrue(offset >= 0);
+            Assert.AssertTrue(size >= 0);
+            Assert.AssertTrue(IsInitialized());
+
+            // Clear the out count
+            outputEntryCount = 0;
+
+            // Succeed if there's no range
+            if (size == 0)
+                return Result.Success;
+
+            // Check that our range is valid
+            if (!Table.Includes(offset, size))
+                return ResultFs.OutOfRange.Log();
+
+            // Find the offset in our tree
+            var visitor = new BucketTree2.Visitor();
+            Result rc = Table.Find(ref visitor, offset);
+            if (rc.IsFailure()) return rc;
+
+            long entryOffset = visitor.Get<Entry>().GetVirtualOffset();
+            if (entryOffset > 0 || !Table.Includes(entryOffset))
+                return ResultFs.InvalidIndirectEntryOffset.Log();
+
+            // Prepare to loop over entries
+            long endOffset = offset + size;
+            int count = 0;
+
+            ref Entry currentEntry = ref visitor.Get<Entry>();
+            while (currentEntry.GetVirtualOffset() < endOffset)
             {
-                return ResultFs.InvalidIndirectStorageSource.Log();
-            }
-
-            long inPos = offset;
-            int outPos = 0;
-            int remaining = destination.Length;
-
-            while (remaining > 0)
-            {
-                long entryPos = inPos - entry.Offset;
-
-                int bytesToRead = (int)Math.Min(entry.OffsetEnd - inPos, remaining);
-
-                Result rc = Sources[entry.SourceIndex].Read(entry.SourceOffset + entryPos, destination.Slice(outPos, bytesToRead));
-                if (rc.IsFailure()) return rc;
-
-                outPos += bytesToRead;
-                inPos += bytesToRead;
-                remaining -= bytesToRead;
-
-                if (inPos >= entry.OffsetEnd)
+                // Try to write the entry to the out list
+                if (entryBuffer.Length != 0)
                 {
-                    entry = entry.Next;
+                    if (count >= entryBuffer.Length)
+                        break;
+
+                    entryBuffer[count] = currentEntry;
+                }
+
+                count++;
+
+                // Advance
+                if (visitor.CanMoveNext())
+                {
+                    rc = visitor.MoveNext();
+                    if (rc.IsFailure()) return rc;
+
+                    currentEntry = ref visitor.Get<Entry>();
+                }
+                else
+                {
+                    break;
                 }
             }
 
+            // Write the entry count
+            outputEntryCount = count;
             return Result.Success;
         }
 
+        protected override unsafe Result DoRead(long offset, Span<byte> destination)
+        {
+            // Validate pre-conditions
+            Assert.AssertTrue(offset >= 0);
+            Assert.AssertTrue(IsInitialized());
+
+            // Succeed if there's nothing to read
+            if (destination.Length == 0)
+                return Result.Success;
+
+            // Pin and recreate the span because C# can't use byref-like types in a closure
+            int bufferSize = destination.Length;
+            fixed (byte* pBuffer = destination)
+            {
+                // Copy the pointer to workaround CS1764.
+                // OperatePerEntry won't store the delegate anywhere, so it should be safe
+                byte* pBuffer2 = pBuffer;
+
+                Result Operate(IStorage storage, long dataOffset, long currentOffset, long currentSize)
+                {
+                    var buffer = new Span<byte>(pBuffer2, bufferSize);
+
+                    return storage.Read(dataOffset,
+                        buffer.Slice((int)(currentOffset - offset), (int)currentSize));
+                }
+
+                return OperatePerEntry(offset, destination.Length, Operate);
+            }
+        }
+
         protected override Result DoWrite(long offset, ReadOnlySpan<byte> source)
         {
-            return ResultFs.UnsupportedOperationInIndirectStorageSetSize.Log();
+            return ResultFs.UnsupportedOperationInIndirectStorageWrite.Log();
         }
 
         protected override Result DoFlush()
@@ -74,36 +185,117 @@ namespace LibHac.FsSystem
             return Result.Success;
         }
 
-        protected override Result DoGetSize(out long size)
-        {
-            size = Length;
-            return Result.Success;
-        }
-
         protected override Result DoSetSize(long size)
         {
             return ResultFs.UnsupportedOperationInIndirectStorageSetSize.Log();
         }
 
-        protected override void Dispose(bool disposing)
+        protected override Result DoGetSize(out long size)
         {
-            if (disposing)
-            {
-                if (!LeaveOpen && Sources != null)
-                {
-                    foreach (IStorage storage in Sources)
-                    {
-                        storage?.Dispose();
-                    }
-                }
-            }
+            size = Table.GetEnd();
+            return Result.Success;
         }
 
-        private RelocationEntry GetRelocationEntry(long offset)
+        private delegate Result OperateFunc(IStorage storage, long dataOffset, long currentOffset, long currentSize);
+
+        private Result OperatePerEntry(long offset, long size, OperateFunc func)
         {
-            int index = RelocationOffsets.BinarySearch(offset);
-            if (index < 0) index = ~index - 1;
-            return RelocationEntries[index];
+            // Validate preconditions
+            Assert.AssertTrue(offset >= 0);
+            Assert.AssertTrue(size >= 0);
+            Assert.AssertTrue(IsInitialized());
+
+            // Succeed if there's nothing to operate on
+            if (size == 0)
+                return Result.Success;
+
+            // Validate arguments
+            if (!Table.Includes(offset, size))
+                return ResultFs.OutOfRange.Log();
+
+            // Find the offset in our tree
+            var visitor = new BucketTree2.Visitor();
+
+            Result rc = Table.Find(ref visitor, offset);
+            if (rc.IsFailure()) return rc;
+
+            long entryOffset = visitor.Get<Entry>().GetVirtualOffset();
+            if (entryOffset < 0 || !Table.Includes(entryOffset))
+                return ResultFs.InvalidIndirectEntryStorageIndex.Log();
+
+            // Prepare to operate in chunks
+            long currentOffset = offset;
+            long endOffset = offset + size;
+
+            while (currentOffset < endOffset)
+            {
+                // Get the current entry
+                var currentEntry = visitor.Get<Entry>();
+
+                // Get and validate the entry's offset
+                long currentEntryOffset = currentEntry.GetVirtualOffset();
+                if (currentEntryOffset > currentOffset)
+                    return ResultFs.InvalidIndirectEntryOffset.Log();
+
+                // Validate the storage index
+                if (currentEntry.StorageIndex < 0 || currentEntry.StorageIndex >= StorageCount)
+                    return ResultFs.InvalidIndirectEntryStorageIndex.Log();
+
+                // todo: Implement continuous reading
+
+                // Get and validate the next entry offset
+                long nextEntryOffset;
+                if (visitor.CanMoveNext())
+                {
+                    rc = visitor.MoveNext();
+                    if (rc.IsFailure()) return rc;
+
+                    nextEntryOffset = visitor.Get<Entry>().GetVirtualOffset();
+                    if (!Table.Includes(nextEntryOffset))
+                        return ResultFs.InvalidIndirectEntryOffset.Log();
+                }
+                else
+                {
+                    nextEntryOffset = Table.GetEnd();
+                }
+
+                if (currentOffset >= nextEntryOffset)
+                    return ResultFs.InvalidIndirectEntryOffset.Log();
+
+                // Get the offset of the entry in the data we read
+                long dataOffset = currentOffset - currentEntryOffset;
+                long dataSize = nextEntryOffset - currentEntryOffset - dataOffset;
+                Assert.AssertTrue(dataSize > 0);
+
+                // Determine how much is left
+                long remainingSize = endOffset - currentOffset;
+                long currentSize = Math.Min(remainingSize, dataSize);
+                Assert.AssertTrue(currentSize <= size);
+
+                {
+                    SubStorage2 currentStorage = DataStorage[currentEntry.StorageIndex];
+
+                    // Get the current data storage's size.
+                    rc = currentStorage.GetSize(out long currentDataStorageSize);
+                    if (rc.IsFailure()) return rc;
+
+                    // Ensure that we remain within range.
+                    long currentEntryPhysicalOffset = currentEntry.GetPhysicalOffset();
+
+                    if (currentEntryPhysicalOffset < 0 || currentEntryPhysicalOffset > currentDataStorageSize)
+                        return ResultFs.IndirectStorageCorrupted.Log();
+
+                    if (currentDataStorageSize < currentEntryPhysicalOffset + dataOffset + currentSize)
+                        return ResultFs.IndirectStorageCorrupted.Log();
+
+                    rc = func(currentStorage, currentEntryPhysicalOffset + dataOffset, currentOffset, currentSize);
+                    if (rc.IsFailure()) return rc;
+                }
+
+                currentOffset += currentSize;
+            }
+
+            return Result.Success;
         }
     }
 }

src/LibHac/FsSystem/NcaUtils/Nca.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
+using LibHac.Common;
 using LibHac.Fs;
 using LibHac.Fs.Fsa;
 using LibHac.FsSystem.RomFs;
@@ -214,6 +215,9 @@ namespace LibHac.FsSystem.NcaUtils
             IStorage patchStorage = patchNca.OpenRawStorage(index);
             IStorage baseStorage = SectionExists(index) ? OpenRawStorage(index) : new NullStorage();
 
+            patchStorage.GetSize(out long patchSize).ThrowIfFailure();
+            baseStorage.GetSize(out long baseSize).ThrowIfFailure();
+
             NcaFsHeader header = patchNca.Header.GetFsHeader(index);
             NcaFsPatchInfo patchInfo = header.GetPatchInfo();
 
@@ -222,9 +226,24 @@ namespace LibHac.FsSystem.NcaUtils
                 return patchStorage;
             }
 
-            IStorage relocationTableStorage = patchStorage.Slice(patchInfo.RelocationTreeOffset, patchInfo.RelocationTreeSize);
+            var treeHeader = new BucketTree2.Header();
+            patchInfo.RelocationTreeHeader.CopyTo(SpanHelpers.AsByteSpan(ref treeHeader));
+            long nodeStorageSize = IndirectStorage.QueryNodeStorageSize(treeHeader.EntryCount);
+            long entryStorageSize = IndirectStorage.QueryEntryStorageSize(treeHeader.EntryCount);
 
-            return new IndirectStorage(relocationTableStorage, true, baseStorage, patchStorage);
+            var relocationTableStorage = new SubStorage2(patchStorage, patchInfo.RelocationTreeOffset, patchInfo.RelocationTreeSize);
+            var cachedTableStorage = new CachedStorage(relocationTableStorage, IndirectStorage.NodeSize, 4, true);
+
+            var tableNodeStorage = new SubStorage2(cachedTableStorage, 0, nodeStorageSize);
+            var tableEntryStorage = new SubStorage2(cachedTableStorage, nodeStorageSize, entryStorageSize);
+
+            var storage = new IndirectStorage();
+            storage.Initialize(tableNodeStorage, tableEntryStorage, treeHeader.EntryCount).ThrowIfFailure();
+
+            storage.SetStorage(0, baseStorage, 0, baseSize);
+            storage.SetStorage(1, patchStorage, 0, patchSize);
+
+            return storage;
         }
 
         public IStorage OpenStorage(int index, IntegrityCheckLevel integrityCheckLevel)

src/LibHac/Util.cs

@@ -48,20 +48,9 @@ namespace LibHac
             return true;
         }
 
-        public static bool SpansEqual<T>(Span<T> a1, Span<T> a2)
+        public static bool SpansEqual<T>(Span<T> a1, Span<T> a2) where T : IEquatable<T>
         {
-            if (a1 == a2) return true;
-            if (a1.Length != a2.Length) return false;
-
-            for (int i = 0; i < a1.Length; i++)
-            {
-                if (!a1[i].Equals(a2[i]))
-                {
-                    return false;
-                }
-            }
-
-            return true;
+            return a1.SequenceEqual(a2);
         }
 
         public static ReadOnlySpan<byte> GetUtf8Bytes(string value)