private static void CheckContents(ZipFile zipFile)
{
Assert.AreEqual("Contents of \"A.txt\".", ReadFile(zipFile, "A.txt"));
Assert.AreEqual("Contents of \"B.txt\".", ReadFile(zipFile, "B.txt"));
Assert.AreEqual("Contents of \"C.txt\".", ReadFile(zipFile, "Folder/C.txt"));
Assert.AreEqual(Lorem, ReadFile(zipFile, "Lorem.txt"));
}
private static void CheckEntries(ZipFile zipFile)
{
// Depending on the ZIP tool: The folder "Folder\" is not always in Entries.
Assert.True(zipFile.Entries.Count == 4 || zipFile.Entries.Count == 5);
Assert.True(zipFile.ContainsEntry("A.txt"));
Assert.True(zipFile.ContainsEntry("B.txt"));
Assert.True(zipFile.ContainsEntry("Folder/C.txt"));
Assert.True(zipFile.ContainsEntry("Lorem.txt"));
}
private static string ReadFile(ZipFile zipFile, string filename)
{
using (var reader = new StreamReader(zipFile[filename].OpenReader()))
{
return reader.ReadToEnd();
}
}
/// <summary>
/// Reads one entry from the zip directory structure in the zip file.
/// </summary>
///
/// <param name="zf">
/// The zipfile for which a directory entry will be read. From this param, the
/// method gets the ReadStream and the expected text encoding
/// (ProvisionalAlternateEncoding) which is used if the entry is not marked
/// UTF-8.
/// </param>
///
/// <param name="previouslySeen">
/// a list of previously seen entry names; used to prevent duplicates.
/// </param>
///
/// <returns>the entry read from the archive.</returns>
internal static ZipEntry ReadDirEntry(ZipFile zf,
Dictionary<String,Object> previouslySeen)
{
System.IO.Stream s = zf.ReadStream;
System.Text.Encoding expectedEncoding = (zf.AlternateEncodingUsage == ZipOption.Always)
? zf.AlternateEncoding
: ZipFile.DefaultEncoding;
int signature = Ionic.Zip.SharedUtilities.ReadSignature(s);
// return null if this is not a local file header signature
if (IsNotValidZipDirEntrySig(signature))
{
s.Seek(-4, System.IO.SeekOrigin.Current);
// Getting "not a ZipDirEntry signature" here is not always wrong or an
// error. This can happen when walking through a zipfile. After the
// last ZipDirEntry, we expect to read an
// EndOfCentralDirectorySignature. When we get this is how we know
// we've reached the end of the central directory.
if (signature != ZipConstants.EndOfCentralDirectorySignature &&
signature != ZipConstants.Zip64EndOfCentralDirectoryRecordSignature &&
signature != ZipConstants.ZipEntrySignature // workitem 8299
)
{
throw new BadReadException(String.Format(CultureInfo.InvariantCulture, " Bad signature (0x{0:X8}) at position 0x{1:X8}", signature, s.Position));
}
return null;
}
int bytesRead = 42 + 4;
byte[] block = new byte[42];
int n = s.Read(block, 0, block.Length);
if (n != block.Length) return null;
int i = 0;
ZipEntry zde = new ZipEntry();
zde.AlternateEncoding = expectedEncoding;
zde._Source = ZipEntrySource.ZipFile;
zde._container = new ZipContainer(zf);
unchecked
{
zde._VersionMadeBy = (short)(block[i++] + block[i++] * 256);
zde._VersionNeeded = (short)(block[i++] + block[i++] * 256);
zde._BitField = (short)(block[i++] + block[i++] * 256);
zde._CompressionMethod = (Int16)(block[i++] + block[i++] * 256);
zde._TimeBlob = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;
zde._LastModified = Ionic.Zip.SharedUtilities.PackedToDateTime(zde._TimeBlob);
zde._timestamp |= ZipEntryTimestamp.DOS;
zde._Crc32 = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;
zde._CompressedSize = (uint)(block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256);
zde._UncompressedSize = (uint)(block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256);
}
// preserve
zde._CompressionMethod_FromZipFile = zde._CompressionMethod;
zde._filenameLength = (short)(block[i++] + block[i++] * 256);
zde._extraFieldLength = (short)(block[i++] + block[i++] * 256);
zde._commentLength = (short)(block[i++] + block[i++] * 256);
zde._diskNumber = (UInt32)(block[i++] + block[i++] * 256);
zde._InternalFileAttrs = (short)(block[i++] + block[i++] * 256);
zde._ExternalFileAttrs = block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256;
zde._RelativeOffsetOfLocalHeader = (uint)(block[i++] + block[i++] * 256 + block[i++] * 256 * 256 + block[i++] * 256 * 256 * 256);
// workitem 7801
zde.IsText = ((zde._InternalFileAttrs & 0x01) == 0x01);
block = new byte[zde._filenameLength];
n = s.Read(block, 0, block.Length);
bytesRead += n;
if ((zde._BitField & 0x0800) == 0x0800)
{
// UTF-8 is in use
zde._FileNameInArchive = Ionic.Zip.SharedUtilities.Utf8StringFromBuffer(block);
}
else
{
zde._FileNameInArchive = Ionic.Zip.SharedUtilities.StringFromBuffer(block, expectedEncoding);
}
// workitem 10330
// insure unique entry names
while (previouslySeen.ContainsKey(zde._FileNameInArchive))
{
zde._FileNameInArchive = CopyHelper.AppendCopyToFileName(zde._FileNameInArchive);
zde._metadataChanged = true;
}
if (zde.AttributesIndicateDirectory)
zde.MarkAsDirectory(); // may append a slash to filename if nec.
// workitem 6898
else if (zde._FileNameInArchive.EndsWith("/", StringComparison.Ordinal)) zde.MarkAsDirectory();
zde._CompressedFileDataSize = zde._CompressedSize;
if ((zde._BitField & 0x01) == 0x01)
{
// this may change after processing the Extra field
zde._Encryption_FromZipFile = zde._Encryption =
EncryptionAlgorithm.PkzipWeak;
zde._sourceIsEncrypted = true;
}
if (zde._extraFieldLength > 0)
{
zde._InputUsesZip64 = (zde._CompressedSize == 0xFFFFFFFF ||
zde._UncompressedSize == 0xFFFFFFFF ||
zde._RelativeOffsetOfLocalHeader == 0xFFFFFFFF);
// Console.WriteLine(" Input uses Z64?: {0}", zde._InputUsesZip64);
bytesRead += zde.ProcessExtraField(s, zde._extraFieldLength);
zde._CompressedFileDataSize = zde._CompressedSize;
}
// we've processed the extra field, so we know the encryption method is set now.
if (zde._Encryption == EncryptionAlgorithm.PkzipWeak)
{
// the "encryption header" of 12 bytes precedes the file data
zde._CompressedFileDataSize -= 12;
}
#if AESCRYPTO
else if (zde.Encryption == EncryptionAlgorithm.WinZipAes128 ||
zde.Encryption == EncryptionAlgorithm.WinZipAes256)
{
zde._CompressedFileDataSize = zde.CompressedSize -
(ZipEntry.GetLengthOfCryptoHeaderBytes(zde.Encryption) + 10);
zde._LengthOfTrailer = 10;
}
#endif
// tally the trailing descriptor
if ((zde._BitField & 0x0008) == 0x0008)
{
// sig, CRC, Comp and Uncomp sizes
if (zde._InputUsesZip64)
zde._LengthOfTrailer += 24;
else
zde._LengthOfTrailer += 16;
}
// workitem 12744
zde.AlternateEncoding = ((zde._BitField & 0x0800) == 0x0800)
? System.Text.Encoding.UTF8
:expectedEncoding;
zde.AlternateEncodingUsage = ZipOption.Always;
if (zde._commentLength > 0)
{
block = new byte[zde._commentLength];
n = s.Read(block, 0, block.Length);
bytesRead += n;
if ((zde._BitField & 0x0800) == 0x0800)
{
// UTF-8 is in use
zde._Comment = Ionic.Zip.SharedUtilities.Utf8StringFromBuffer(block);
}
else
{
zde._Comment = Ionic.Zip.SharedUtilities.StringFromBuffer(block, expectedEncoding);
}
}
//zde._LengthOfDirEntry = bytesRead;
return zde;
}
private static void ReadZipFileComment(ZipFile zf)
{
// read the comment here
byte[] block = new byte[2];
zf.ReadStream.Read(block, 0, block.Length);
Int16 commentLength = (short)(block[0] + block[1] * 256);
if (commentLength > 0)
{
block = new byte[commentLength];
zf.ReadStream.Read(block, 0, block.Length);
// workitem 10392 - prefer ProvisionalAlternateEncoding,
// first. The fix for workitem 6513 tried to use UTF8
// only as necessary, but that is impossible to test
// for, in this direction. There's no way to know what
// characters the already-encoded bytes refer
// to. Therefore, must do what the user tells us.
string s1 = zf.AlternateEncoding.GetString(block, 0, block.Length);
zf.Comment = s1;
}
}
private static void Zip64SeekToCentralDirectory(ZipFile zf)
{
Stream s = zf.ReadStream;
byte[] block = new byte[16];
// seek back to find the ZIP64 EoCD.
// I think this might not work for .NET CF ?
s.Seek(-40, SeekOrigin.Current);
s.Read(block, 0, 16);
Int64 offset64 = BitConverter.ToInt64(block, 8);
// change for workitem 8098
s.Seek(offset64, SeekOrigin.Begin);
//zf.SeekFromOrigin(Offset64);
uint datum = (uint)Ionic.Zip.SharedUtilities.ReadInt(s);
if (datum != ZipConstants.Zip64EndOfCentralDirectoryRecordSignature)
throw new BadReadException(String.Format(CultureInfo.InvariantCulture, " Bad signature (0x{0:X8}) looking for ZIP64 EoCD Record at position 0x{1:X8}", datum, s.Position));
s.Read(block, 0, 8);
Int64 Size = BitConverter.ToInt64(block, 0);
block = new byte[Size];
s.Read(block, 0, block.Length);
offset64 = BitConverter.ToInt64(block, 36);
// change for workitem 8098
s.Seek(offset64, SeekOrigin.Begin);
//zf.SeekFromOrigin(Offset64);
}
private static void ReadIntoInstance(ZipFile zf)
{
Stream s = zf.ReadStream;
try
{
if (!s.CanSeek)
{
ReadIntoInstance_Orig(zf);
return;
}
// change for workitem 8098
//zf._originPosition = s.Position;
// Try reading the central directory, rather than scanning the file.
uint datum = ReadFirstFourBytes(s);
if (datum == ZipConstants.EndOfCentralDirectorySignature)
return;
// start at the end of the file...
// seek backwards a bit, then look for the EoCD signature.
int nTries = 0;
bool success = false;
// The size of the end-of-central-directory-footer plus 2 bytes is 18.
// This implies an archive comment length of 0. We'll add a margin of
// safety and start "in front" of that, when looking for the
// EndOfCentralDirectorySignature
long posn = s.Length - 64;
long maxSeekback = Math.Max(s.Length - 0x4000, 10);
do
{
if (posn < 0) posn = 0; // BOF
s.Seek(posn, SeekOrigin.Begin);
long bytesRead = SharedUtilities.FindSignature(s, (int)ZipConstants.EndOfCentralDirectorySignature);
if (bytesRead != -1)
success = true;
else
{
if (posn==0) break; // started at the BOF and found nothing
nTries++;
// Weird: with NETCF, negative offsets from SeekOrigin.End DO
// NOT WORK. So rather than seek a negative offset, we seek
// from SeekOrigin.Begin using a smaller number.
posn -= (32 * (nTries + 1) * nTries);
}
}
while (!success && posn > maxSeekback);
if (success)
{
// workitem 8299
zf._locEndOfCDS = s.Position - 4;
byte[] block = new byte[16];
s.Read(block, 0, block.Length);
zf._diskNumberWithCd = BitConverter.ToUInt16(block, 2);
if (zf._diskNumberWithCd == 0xFFFF)
throw new ZipException("Spanned archives with more than 65534 segments are not supported at this time.");
zf._diskNumberWithCd++; // I think the number in the file differs from reality by 1
int i = 12;
uint offset32 = (uint) BitConverter.ToUInt32(block, i);
if (offset32 == 0xFFFFFFFF)
{
Zip64SeekToCentralDirectory(zf);
}
else
{
// change for workitem 8098
s.Seek(offset32, SeekOrigin.Begin);
}
ReadCentralDirectory(zf);
}
else
{
// Could not find the central directory.
// Fallback to the old method.
// workitem 8098: ok
//s.Seek(zf._originPosition, SeekOrigin.Begin);
s.Seek(0L, SeekOrigin.Begin);
ReadIntoInstance_Orig(zf);
}
}
catch (Exception ex1)
{
throw new ZipException("Cannot read that as a ZipFile", ex1);
}
}
// build the TOC by reading each entry in the file.
private static void ReadIntoInstance_Orig(ZipFile zf)
{
//zf._entries = new System.Collections.Generic.List<ZipEntry>();
zf._entries = new System.Collections.Generic.Dictionary<String,ZipEntry>();
ZipEntry e;
// work item 6647: PK00 (packed to removable disk)
bool firstEntry = true;
ZipContainer zc = new ZipContainer(zf);
while ((e = ZipEntry.ReadEntry(zc, firstEntry)) != null)
{
zf._entries.Add(e.FileName,e);
firstEntry = false;
}
// read the zipfile's central directory structure here.
// workitem 9912
// But, because it may be corrupted, ignore errors.
try
{
ZipEntry de;
// in lieu of hashset, use a dictionary
var previouslySeen = new Dictionary<String,Object>();
while ((de = ZipEntry.ReadDirEntry(zf, previouslySeen)) != null)
{
// Housekeeping: Since ZipFile exposes ZipEntry elements in the enumerator,
// we need to copy the comment that we grab from the ZipDirEntry
// into the ZipEntry, so the application can access the comment.
// Also since ZipEntry is used to Write zip files, we need to copy the
// file attributes to the ZipEntry as appropriate.
ZipEntry e1 = zf._entries[de.FileName];
if (e1 != null)
{
e1._Comment = de.Comment;
if (de.IsDirectory) e1.MarkAsDirectory();
}
previouslySeen.Add(de.FileName,null); // to prevent dupes
}
// workitem 8299
if (zf._locEndOfCDS > 0)
zf.ReadStream.Seek(zf._locEndOfCDS, SeekOrigin.Begin);
ReadCentralDirectoryFooter(zf);
}
catch (ZipException) { }
catch (IOException) { }
}
private static void ReadCentralDirectoryFooter(ZipFile zf)
{
Stream s = zf.ReadStream;
int signature = Ionic.Zip.SharedUtilities.ReadSignature(s);
byte[] block = null;
int j = 0;
if (signature == ZipConstants.Zip64EndOfCentralDirectoryRecordSignature)
{
// We have a ZIP64 EOCD
// This data block is 4 bytes sig, 8 bytes size, 44 bytes fixed data,
// followed by a variable-sized extension block. We have read the sig already.
// 8 - datasize (64 bits)
// 2 - version made by
// 2 - version needed to extract
// 4 - number of this disk
// 4 - number of the disk with the start of the CD
// 8 - total number of entries in the CD on this disk
// 8 - total number of entries in the CD
// 8 - size of the CD
// 8 - offset of the CD
// -----------------------
// 52 bytes
block = new byte[8 + 44];
s.Read(block, 0, block.Length);
Int64 DataSize = BitConverter.ToInt64(block, 0); // == 44 + the variable length
if (DataSize < 44)
throw new ZipException("Bad size in the ZIP64 Central Directory.");
//zf._versionMadeBy = BitConverter.ToUInt16(block, j);
j += 2;
//zf._versionNeededToExtract = BitConverter.ToUInt16(block, j);
j += 2;
zf._diskNumberWithCd = BitConverter.ToUInt32(block, j);
j += 2;
//zf._diskNumberWithCd++; // hack!!
// read the extended block
block = new byte[DataSize - 44];
s.Read(block, 0, block.Length);
// discard the result
signature = Ionic.Zip.SharedUtilities.ReadSignature(s);
if (signature != ZipConstants.Zip64EndOfCentralDirectoryLocatorSignature)
throw new ZipException("Inconsistent metadata in the ZIP64 Central Directory.");
block = new byte[16];
s.Read(block, 0, block.Length);
// discard the result
signature = Ionic.Zip.SharedUtilities.ReadSignature(s);
}
// Throw if this is not a signature for "end of central directory record"
// This is a sanity check.
if (signature != ZipConstants.EndOfCentralDirectorySignature)
{
s.Seek(-4, SeekOrigin.Current);
throw new BadReadException(String.Format(CultureInfo.InvariantCulture,
"Bad signature ({0:X8}) at position 0x{1:X8}",
signature, s.Position));
}
// read the End-of-Central-Directory-Record
block = new byte[16];
zf.ReadStream.Read(block, 0, block.Length);
// off sz data
// -------------------------------------------------------
// 0 4 end of central dir signature (0x06054b50)
// 4 2 number of this disk
// 6 2 number of the disk with start of the central directory
// 8 2 total number of entries in the central directory on this disk
// 10 2 total number of entries in the central directory
// 12 4 size of the central directory
// 16 4 offset of start of central directory with respect to the starting disk number
// 20 2 ZIP file comment length
// 22 ?? ZIP file comment
if (zf._diskNumberWithCd == 0)
{
zf._diskNumberWithCd = BitConverter.ToUInt16(block, 2);
//zf._diskNumberWithCd++; // hack!!
}
// read the comment here
ReadZipFileComment(zf);
}
private static void ReadCentralDirectory(ZipFile zf)
{
// We must have the central directory footer record, in order to properly
// read zip dir entries from the central directory. This because the logic
// knows when to open a spanned file when the volume number for the central
// directory differs from the volume number for the zip entry. The
// _diskNumberWithCd was set when originally finding the offset for the
// start of the Central Directory.
ZipEntry de;
// in lieu of hashset, use a dictionary
var previouslySeen = new Dictionary<String,object>();
while ((de = ZipEntry.ReadDirEntry(zf, previouslySeen)) != null)
{
de.ResetDirEntry();
zf._entries.Add(de.FileName,de);
previouslySeen.Add(de.FileName, null); // to prevent dupes
}
// workitem 8299
if (zf._locEndOfCDS > 0)
zf.ReadStream.Seek(zf._locEndOfCDS, SeekOrigin.Begin);
ReadCentralDirectoryFooter(zf);
// We keep the read stream open after reading.
}
private static ZipFile Read(Stream zipStream, System.Text.Encoding encoding)
{
if (zipStream == null)
throw new ArgumentNullException("zipStream");
ZipFile zf = new ZipFile();
zf._alternateEncoding = encoding ?? ZipFile.DefaultEncoding;
zf._alternateEncodingUsage = ZipOption.Always;
zf._readstream = (zipStream.Position == 0L)
? zipStream
: new OffsetStream(zipStream);
ReadIntoInstance(zf);
return zf;
}
//--------------------------------------------------------------
/// <summary>
/// Initializes a new instance of the <see cref="ZipStorage"/> class.
/// </summary>
/// <param name="storage">The storage that contains the ZIP archive.</param>
/// <param name="fileName">The file name (incl. path) of the ZIP archive.</param>
/// <remarks>
/// An exception is raised if the ZIP archive could not be opened.
/// </remarks>
/// <exception cref="ArgumentNullException">
/// <paramref name="storage"/> or <paramref name="fileName"/> is null.
/// </exception>
public ZipStorage(Storage storage, string fileName)
{
if (storage == null)
throw new ArgumentNullException("storage");
if (fileName == null)
throw new ArgumentNullException("fileName");
Storage = storage;
FileName = fileName;
_zipStream = storage.OpenFile(fileName);
try
{
_zipFile = ZipFile.Read(_zipStream);
return;
}
catch
{
_zipStream.Dispose();
#if !ANDROID
throw;
#endif
}
#if ANDROID
// Android asset streams do not support Stream.Length/Position or seeking.
// We need to copy the asset first to normal file.
string tempFileName = storage.GetRealPath(fileName) ?? fileName;
tempFileName = tempFileName.Replace('\\', '_');
tempFileName = tempFileName.Replace('/', '_');
tempFileName = "DigitalRune_Temp_" + tempFileName;
tempFileName = System.IO.Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Personal), tempFileName);
// We copy the files once for each session because the asset files could have change.
// To check if a file has changed, we would have to compare the whole file because ZIP files
// store their dictionary at the end of the file. :-(
// Filenames of the temp files are stored in a list. Other ZipStorages for the same
// file will use the existing temp file.
lock(_tempFiles)
{
if (!_tempFiles.Contains(tempFileName))
{
_tempFiles.Add(tempFileName);
using (_zipStream = storage.OpenFile(fileName))
{
using (var dest = File.Create(tempFileName))
_zipStream.CopyTo(dest);
}
}
}
_zipStream = File.OpenRead(tempFileName);
try
{
_zipFile = ZipFile.Read(_zipStream);
}
catch
{
_zipStream.Dispose();
throw;
}
#endif
}
public ZipContainer(ZipFile zf)
{
_zf = zf;
}
