Remove ZipHelper.ReadBytes wrapper methods and use Stream.ReadAtLeast directly (#118629)

* Initial plan

* Simplify ZipHelper.ReadBytes by using Stream.ReadAtLeast default behavior

Co-authored-by: rzikm <[email protected]>

* Remove ZipHelper.ReadBytes wrapper methods and use Stream.ReadAtLeast directly

Co-authored-by: stephentoub <[email protected]>

---------

Co-authored-by: Copilot <[email protected]>
Co-authored-by: rzikm <[email protected]>
Co-authored-by: stephentoub <[email protected]>

Author: 3 people

src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Async.cs

@@ -172,9 +172,9 @@ internal async Task LoadCompressedBytesIfNeededAsync(CancellationToken cancellat
 
             for (int i = 0; i < _compressedBytes.Length - 1; i++)
             {
-                await ZipHelper.ReadBytesAsync(_archive.ArchiveStream, _compressedBytes[i], maxSingleBufferSize, cancellationToken).ConfigureAwait(false);
+                await _archive.ArchiveStream.ReadAtLeastAsync(_compressedBytes[i], maxSingleBufferSize, throwOnEndOfStream: true, cancellationToken).ConfigureAwait(false);
             }
-            await ZipHelper.ReadBytesAsync(_archive.ArchiveStream, _compressedBytes[_compressedBytes.Length - 1], (int)(_compressedSize % maxSingleBufferSize), cancellationToken).ConfigureAwait(false);
+            await _archive.ArchiveStream.ReadAtLeastAsync(_compressedBytes[_compressedBytes.Length - 1], (int)(_compressedSize % maxSingleBufferSize), throwOnEndOfStream: true, cancellationToken).ConfigureAwait(false);
         }
     }
 

src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs

@@ -678,9 +678,9 @@ internal void LoadCompressedBytesIfNeeded()
 
                 for (int i = 0; i < _compressedBytes.Length - 1; i++)
                 {
-                    ZipHelper.ReadBytes(_archive.ArchiveStream, _compressedBytes[i], maxSingleBufferSize);
+                    _archive.ArchiveStream.ReadAtLeast(_compressedBytes[i], maxSingleBufferSize, throwOnEndOfStream: true);
                 }
-                ZipHelper.ReadBytes(_archive.ArchiveStream, _compressedBytes[_compressedBytes.Length - 1], (int)(_compressedSize % maxSingleBufferSize));
+                _archive.ArchiveStream.ReadAtLeast(_compressedBytes[_compressedBytes.Length - 1], (int)(_compressedSize % maxSingleBufferSize), throwOnEndOfStream: true);
             }
         }
 

src/libraries/System.IO.Compression/src/System/IO/Compression/ZipHelper.Async.cs

@@ -10,22 +10,6 @@ namespace System.IO.Compression;
 
 internal static partial class ZipHelper
 {
-    /// <summary>
-    /// Asynchronously reads exactly bytesToRead out of stream, unless it is out of bytes.
-    /// </summary>
-    internal static async Task<int> ReadBytesAsync(Stream stream, Memory<byte> buffer, int bytesToRead, CancellationToken cancellationToken)
-    {
-        cancellationToken.ThrowIfCancellationRequested();
-
-        int bytesRead = await stream.ReadAtLeastAsync(buffer, bytesToRead, throwOnEndOfStream: false, cancellationToken).ConfigureAwait(false);
-
-        if (bytesRead < bytesToRead)
-        {
-            throw new IOException(SR.UnexpectedEndOfStream);
-        }
-        return bytesRead;
-    }
-
     // Asynchronously assumes all bytes of signatureToFind are non zero, looks backwards from current position in stream,
     // assumes maxBytesToRead is positive, ensures to not read beyond the provided max number of bytes,
     // if the signature is found then returns true and positions stream at first byte of signature
@@ -114,14 +98,14 @@ private static async Task<int> SeekBackwardsAndReadAsync(Stream stream, Memory<b
         {
             Debug.Assert(overlap <= buffer.Length);
             stream.Seek(-(buffer.Length - overlap), SeekOrigin.Current);
-            bytesRead = await ReadBytesAsync(stream, buffer, buffer.Length, cancellationToken).ConfigureAwait(false);
+            bytesRead = await stream.ReadAtLeastAsync(buffer, buffer.Length, throwOnEndOfStream: true, cancellationToken).ConfigureAwait(false);
             stream.Seek(-buffer.Length, SeekOrigin.Current);
         }
         else
         {
             int bytesToRead = (int)stream.Position;
             stream.Seek(0, SeekOrigin.Begin);
-            bytesRead = await ReadBytesAsync(stream, buffer, bytesToRead, cancellationToken).ConfigureAwait(false);
+            bytesRead = await stream.ReadAtLeastAsync(buffer, bytesToRead, throwOnEndOfStream: true, cancellationToken).ConfigureAwait(false);
             stream.Seek(0, SeekOrigin.Begin);
         }
 

src/libraries/System.IO.Compression/src/System/IO/Compression/ZipHelper.cs

@@ -32,19 +32,6 @@ internal static Encoding GetEncoding(string text)
         return Encoding.ASCII;
     }
 
-    /// <summary>
-    /// Reads exactly bytesToRead out of stream, unless it is out of bytes
-    /// </summary>
-    internal static int ReadBytes(Stream stream, Span<byte> buffer, int bytesToRead)
-    {
-        int bytesRead = stream.ReadAtLeast(buffer, bytesToRead, throwOnEndOfStream: false);
-        if (bytesRead < bytesToRead)
-        {
-            throw new IOException(SR.UnexpectedEndOfStream);
-        }
-        return bytesRead;
-    }
-
     // will silently return InvalidDateIndicator if the uint is not a valid Dos DateTime
     internal static DateTime DosTimeToDateTime(uint dateTime)
     {
@@ -183,14 +170,14 @@ private static int SeekBackwardsAndRead(Stream stream, Span<byte> buffer, int ov
         {
             Debug.Assert(overlap <= buffer.Length);
             stream.Seek(-(buffer.Length - overlap), SeekOrigin.Current);
-            bytesRead = ReadBytes(stream, buffer, buffer.Length);
+            bytesRead = stream.ReadAtLeast(buffer, buffer.Length, throwOnEndOfStream: true);
             stream.Seek(-buffer.Length, SeekOrigin.Current);
         }
         else
         {
             int bytesToRead = (int)stream.Position;
             stream.Seek(0, SeekOrigin.Begin);
-            bytesRead = ReadBytes(stream, buffer, bytesToRead);
+            bytesRead = stream.ReadAtLeast(buffer, bytesToRead, throwOnEndOfStream: true);
             stream.Seek(0, SeekOrigin.Begin);
         }