Add a new more complex unit test (#105)

Add a new more complete unit test which emulates how Xamarin.Android uses LibZipSharp.
Also made a small change to the way we handle reading from a stream. According to the documentation stream.Read can return a value less than what was asked. So we need to keep reading until we get all the data we expected or an error is thrown.

Author: dellis1972

LibZipSharp.UnitTest/ZipTests.cs

@@ -257,6 +257,85 @@ public void CheckForUnknownCompressionMethods ()
 }
 }
 
+[Test]
+publicvoidSimulateXamarinAndroidUsage([Values(true,false)]boolcopyArchive,[Values(true,false)]booluseFiles)
+{
+stringfilePath=Path.GetFullPath("packaged_resources");
+if(!File.Exists(filePath)){
+filePath=Path.GetFullPath(Path.Combine("LibZipSharp.UnitTest","packaged_resources"));
+}
+
+stringbaseArchive=$"base_{copyArchive}_{useFiles}.zip";
+
+if(File.Exists(baseArchive))
+File.Delete(baseArchive);
+
+varmode=FileMode.Create;
+if(copyArchive){
+File.Copy(filePath,baseArchive);
+mode=FileMode.Open;
+}
+
+List<(stringname,CompressionMethodc,ulongsize)>expectedFiles=newList<(stringname,CompressionMethodc,ulongsize)>();
+// use a specific seed so we always generate the same files
+Randomrnd=newRandom(3456464);
+
+using(varbaseZip=newZipWrapper(baseArchive,mode)){
+using(varzip=ZipArchive.Open(filePath,FileMode.Open)){
+foreach(varentryinzip){
+varentryName=entry.FullName;
+if(entryName.Contains("\\")){
+entryName=entryName.Replace('\\','/');
+}
+expectedFiles.Add((entryName,entry.CompressionMethod,entry.Size));
+if(copyArchive)
+continue;
+varms=newMemoryStream();
+entry.Extract(ms);
+TestContext.Out.WriteLine($"Adding {entryName} to base.zip");
+baseZip.Archive.AddStream(ms,entryName,compressionMethod:entry.CompressionMethod);
+}
+}
+
+baseZip.FixupWindowsPathSeparators((a,b)=>TestContext.Out.WriteLine($"Fixing up malformed entry `{a}` -> `{b}`"));
+
+for(inti=0;i<200;i++){
+uintfileSize=(uint)rnd.Next(341,3535592);
+byte[]buffer=newbyte[fileSize];
+rnd.NextBytes(buffer);
+CompressionMethodcompression=rnd.NextDouble()<0.8?CompressionMethod.Deflate:CompressionMethod.Store;
+stringentryName=$"temp/file_{i}_size_{fileSize}_{compression}.bin";
+stringarchivePath=rnd.NextDouble()<0.3?entryName:Path.GetFileName(entryName);
+TestContext.Out.WriteLine($"Adding {entryName} to base.zip");
+if(useFiles){
+Directory.CreateDirectory("temp");
+File.WriteAllBytes(entryName,buffer);
+baseZip.Archive.AddFile(entryName,archivePath,compressionMethod:compression);
+}else{
+varms=newMemoryStream(buffer);
+ms.Position=0;
+baseZip.Archive.AddStream(ms,archivePath,compressionMethod:compression);
+}
+expectedFiles.Add((archivePath,compression,fileSize));
+
+if(rnd.NextDouble()<0.2)
+baseZip.Flush();
+}
+
+}
+using(varzip=ZipArchive.Open(baseArchive,FileMode.Open,strictConsistencyChecks:true)){
+foreach(varfileinexpectedFiles){
+Assert.IsTrue(zip.ContainsEntry(file.name),$"zip should contain {file}.");
+vare=zip.ReadEntry(file.name);
+Assert.AreEqual(file.size,e.Size,$"{file} should be {file.size} but was {e.Size}.");
+Assert.AreEqual(file.c,e.CompressionMethod,$"{file} should be {file.c} but was {e.CompressionMethod}.");
+}
+}
+
+if(File.Exists(baseArchive))
+File.Delete(baseArchive);
+}
+
 [Test]
 publicvoidInMemoryZipFile()
 {

LibZipSharp.UnitTest/ZipWrapper.cs

@@ -0,0 +1,65 @@
+usingNUnit.Framework;
+usingSystem;
+usingSystem.Collections.Generic;
+usingSystem.IO;
+usingSystem.Text;
+usingSystem.Threading;
+usingXamarin.Tools.Zip;
+usingUnix=Mono.Unix;
+
+namespaceTests{
+publicclassZipWrapper:IDisposable{
+ZipArchivearchive;
+stringfilename;
+publicZipArchiveArchive=>archive;
+
+publicZipWrapper(stringfile,FileModemode=FileMode.CreateNew){
+filename=file;
+archive=ZipArchive.Open(filename,mode);
+}
+
+publicvoidFlush(){
+if(archive!=null){
+archive.Close();
+archive.Dispose();
+archive=null;
+}
+archive=ZipArchive.Open(filename,FileMode.Open);
+}
+
+/// <summary>
+/// HACK: aapt2 is creating zip entries on Windows such as `assets\subfolder/asset2.txt`
+/// </summary>
+publicvoidFixupWindowsPathSeparators(Action<string,string>onRename)
+{
+boolmodified=false;
+foreach(varentryinarchive){
+if(entry.FullName.Contains("\\")){
+varname=entry.FullName.Replace('\\','/');
+onRename?.Invoke(entry.FullName,name);
+entry.Rename(name);
+modified=true;
+}
+}
+if(modified){
+Flush();
+}
+}
+
+publicvoidDispose()
+{
+Dispose(true);
+GC.SuppressFinalize(this);
+}
+
+protectedvirtualvoidDispose(booldisposing){
+if(disposing){
+if(archive!=null){
+archive.Close();
+archive.Dispose();
+archive=null;
+}
+}
+}
+}
+}

LibZipSharp/Xamarin.Tools.Zip/ZipArchive.cs

@@ -852,8 +852,14 @@ internal static unsafe Int64 stream_callback (IntPtr state, IntPtr data, UInt64
 length=(int)Math.Min(stream.Length-stream.Position,length);
 buffer=ArrayPool<byte>.Shared.Rent(length);
 try{
-intbytesRead=stream.Read(buffer,0,length);
-Marshal.Copy(buffer,0,data,bytesRead);
+intbytesRead=0;
+intstartIndex=0;
+while(length>0){
+bytesRead=stream.Read(buffer,0,length);
+Marshal.Copy(buffer,startIndex,data,bytesRead);
+startIndex+=bytesRead;
+length-=bytesRead;
+}
 returnbytesRead;
 }finally{
 ArrayPool<byte>.Shared.Return(buffer);