/// <summary>
/// Closes the current entry, updating header and footer information as required
/// </summary>
/// <exception cref="System.IO.IOException">
/// An I/O error occurs.
/// </exception>
/// <exception cref="System.InvalidOperationException">
/// No entry is active.
/// </exception>
public void CloseEntry()
{
if (curEntry == null) {
throw new InvalidOperationException("No open entry");
}
// First finish the deflater, if appropriate
if (curMethod == CompressionMethod.Deflated) {
base.Finish();
}
long csize = curMethod == CompressionMethod.Deflated ? def.TotalOut : size;
if (curEntry.Size < 0) {
curEntry.Size = size;
} else if (curEntry.Size != size) {
throw new ZipException("size was " + size + ", but I expected " + curEntry.Size);
}
if (curEntry.CompressedSize < 0) {
curEntry.CompressedSize = csize;
} else if (curEntry.CompressedSize != csize) {
throw new ZipException("compressed size was " + csize + ", but I expected " + curEntry.CompressedSize);
}
if (curEntry.Crc < 0) {
curEntry.Crc = crc.Value;
} else if (curEntry.Crc != crc.Value) {
throw new ZipException("crc was " + crc.Value + ", but I expected " + curEntry.Crc);
}
offset += csize;
if (offset > 0xffffffff) {
throw new ZipException("Maximum Zip file size exceeded");
}
if (curEntry.IsCrypted == true) {
curEntry.CompressedSize += ZipConstants.CRYPTO_HEADER_SIZE;
}
// Patch the header if possible
if (patchEntryHeader == true) {
long curPos = baseOutputStream.Position;
baseOutputStream.Seek(headerPatchPos, SeekOrigin.Begin);
WriteLeInt((int)curEntry.Crc);
WriteLeInt((int)curEntry.CompressedSize);
WriteLeInt((int)curEntry.Size);
baseOutputStream.Seek(curPos, SeekOrigin.Begin);
patchEntryHeader = false;
}
// Add data descriptor if flagged as required
if ((curEntry.Flags & 8) != 0) {
WriteLeInt(ZipConstants.EXTSIG);
WriteLeInt((int)curEntry.Crc);
WriteLeInt((int)curEntry.CompressedSize);
WriteLeInt((int)curEntry.Size);
offset += ZipConstants.EXTHDR;
}
entries.Add(curEntry);
curEntry = null;
}
/// <summary>
/// Search for and read the central directory of a zip file filling the entries
/// array. This is called exactly once by the constructors.
/// </summary>
/// <exception cref="System.IO.IOException">
/// An i/o error occurs.
/// </exception>
/// <exception cref="AdHocDesktop.SharpZipLib.Zip.ZipException">
/// The central directory is malformed or cannot be found
/// </exception>
void ReadEntries()
{
// Search for the End Of Central Directory. When a zip comment is
// present the directory may start earlier.
//
// TODO: The search is limited to 64K which is the maximum size of a trailing comment field to aid speed.
// This should be compatible with both SFX and ZIP files but has only been tested for Zip files
// Need to confirm this is valid in all cases.
// Could also speed this up by reading memory in larger blocks?
if (baseStream.CanSeek == false)
{
throw new ZipException("ZipFile stream must be seekable");
}
long pos = baseStream.Length - ZipConstants.ENDHDR;
if (pos <= 0)
{
throw new ZipException("File is too small to be a Zip file");
}
long giveUpMarker = Math.Max(pos - 0x10000, 0);
do
{
if (pos < giveUpMarker)
{
throw new ZipException("central directory not found, probably not a zip file");
}
baseStream.Seek(pos--, SeekOrigin.Begin);
} while (ReadLeInt() != ZipConstants.ENDSIG);
int thisDiskNumber = ReadLeShort();
int startCentralDirDisk = ReadLeShort();
int entriesForThisDisk = ReadLeShort();
int entriesForWholeCentralDir = ReadLeShort();
int centralDirSize = ReadLeInt();
int offsetOfCentralDir = ReadLeInt();
int commentSize = ReadLeShort();
byte[] zipComment = new byte[commentSize];
baseStream.Read(zipComment, 0, zipComment.Length);
comment = ZipConstants.ConvertToString(zipComment);
/* Its seems possible that this is too strict, more digging required.
* if (thisDiskNumber != 0 || startCentralDirDisk != 0 || entriesForThisDisk != entriesForWholeCentralDir) {
* throw new ZipException("Spanned archives are not currently handled");
* }
*/
entries = new ZipEntry[entriesForWholeCentralDir];
baseStream.Seek(offsetOfCentralDir, SeekOrigin.Begin);
for (int i = 0; i < entriesForWholeCentralDir; i++)
{
if (ReadLeInt() != ZipConstants.CENSIG)
{
throw new ZipException("Wrong Central Directory signature");
}
int versionMadeBy = ReadLeShort();
int versionToExtract = ReadLeShort();
int bitFlags = ReadLeShort();
int method = ReadLeShort();
int dostime = ReadLeInt();
int crc = ReadLeInt();
int csize = ReadLeInt();
int size = ReadLeInt();
int nameLen = ReadLeShort();
int extraLen = ReadLeShort();
int commentLen = ReadLeShort();
int diskStartNo = ReadLeShort(); // Not currently used
int internalAttributes = ReadLeShort(); // Not currently used
int externalAttributes = ReadLeInt();
int offset = ReadLeInt();
byte[] buffer = new byte[Math.Max(nameLen, commentLen)];
baseStream.Read(buffer, 0, nameLen);
string name = ZipConstants.ConvertToString(buffer, nameLen);
ZipEntry entry = new ZipEntry(name, versionToExtract, versionMadeBy);
entry.CompressionMethod = (CompressionMethod)method;
entry.Crc = crc & 0xffffffffL;
entry.Size = size & 0xffffffffL;
entry.CompressedSize = csize & 0xffffffffL;
entry.Flags = bitFlags;
entry.DosTime = (uint)dostime;
if (extraLen > 0)
{
byte[] extra = new byte[extraLen];
baseStream.Read(extra, 0, extraLen);
entry.ExtraData = extra;
}
if (commentLen > 0)
{
baseStream.Read(buffer, 0, commentLen);
entry.Comment = ZipConstants.ConvertToString(buffer, commentLen);
}
entry.ZipFileIndex = i;
entry.Offset = offset;
entry.ExternalFileAttributes = externalAttributes;
entries[i] = entry;
}
}
/// <summary>
/// Starts a new Zip entry. It automatically closes the previous
/// entry if present.
/// All entry elements bar name are optional, but must be correct if present.
/// If the compression method is stored and the output is not patchable
/// the compression for that entry is automatically changed to deflate level 0
/// </summary>
/// <param name="entry">
/// the entry.
/// </param>
/// <exception cref="System.IO.IOException">
/// if an I/O error occured.
/// </exception>
/// <exception cref="System.InvalidOperationException">
/// if stream was finished
/// </exception>
/// <exception cref="ZipException">
/// Too many entries in the Zip file<br/>
/// Entry name is too long<br/>
/// Finish has already been called<br/>
/// </exception>
public void PutNextEntry(ZipEntry entry)
{
if (entries == null) {
throw new InvalidOperationException("ZipOutputStream was finished");
}
if (curEntry != null) {
CloseEntry();
}
if (entries.Count >= 0xffff) {
throw new ZipException("Too many entries for Zip file");
}
CompressionMethod method = entry.CompressionMethod;
int compressionLevel = defaultCompressionLevel;
entry.Flags = 0;
patchEntryHeader = false;
bool headerInfoAvailable = true;
if (method == CompressionMethod.Stored) {
if (entry.CompressedSize >= 0) {
if (entry.Size < 0) {
entry.Size = entry.CompressedSize;
} else if (entry.Size != entry.CompressedSize) {
throw new ZipException("Method STORED, but compressed size != size");
}
} else {
if (entry.Size >= 0) {
entry.CompressedSize = entry.Size;
}
}
if (entry.Size < 0 || entry.Crc < 0) {
if (CanPatchEntries == true) {
headerInfoAvailable = false;
}
else {
method = CompressionMethod.Deflated;
compressionLevel = 0;
}
}
}
if (method == CompressionMethod.Deflated) {
if (entry.Size == 0) {
entry.CompressedSize = entry.Size;
entry.Crc = 0;
method = CompressionMethod.Stored;
} else if (entry.CompressedSize < 0 || entry.Size < 0 || entry.Crc < 0) {
headerInfoAvailable = false;
}
}
if (headerInfoAvailable == false) {
if (CanPatchEntries == false) {
entry.Flags |= 8;
} else {
patchEntryHeader = true;
}
}
if (Password != null) {
entry.IsCrypted = true;
if (entry.Crc < 0) {
entry.Flags |= 8;
}
}
entry.Offset = (int)offset;
entry.CompressionMethod = (CompressionMethod)method;
curMethod = method;
// Write the local file header
WriteLeInt(ZipConstants.LOCSIG);
WriteLeShort(entry.Version);
WriteLeShort(entry.Flags);
WriteLeShort((byte)method);
WriteLeInt((int)entry.DosTime);
if (headerInfoAvailable == true) {
WriteLeInt((int)entry.Crc);
WriteLeInt(entry.IsCrypted ? (int)entry.CompressedSize + ZipConstants.CRYPTO_HEADER_SIZE : (int)entry.CompressedSize);
WriteLeInt((int)entry.Size);
} else {
if (patchEntryHeader == true) {
headerPatchPos = baseOutputStream.Position;
}
WriteLeInt(0); // Crc
WriteLeInt(0); // Compressed size
WriteLeInt(0); // Uncompressed size
}
byte[] name = ZipConstants.ConvertToArray(entry.Name);
if (name.Length > 0xFFFF) {
throw new ZipException("Entry name too long.");
}
byte[] extra = entry.ExtraData;
if (extra == null) {
extra = new byte[0];
}
if (extra.Length > 0xFFFF) {
throw new ZipException("Extra data too long.");
}
WriteLeShort(name.Length);
WriteLeShort(extra.Length);
baseOutputStream.Write(name, 0, name.Length);
baseOutputStream.Write(extra, 0, extra.Length);
offset += ZipConstants.LOCHDR + name.Length + extra.Length;
// Activate the entry.
curEntry = entry;
crc.Reset();
if (method == CompressionMethod.Deflated) {
def.Reset();
def.SetLevel(compressionLevel);
}
size = 0;
if (entry.IsCrypted == true) {
if (entry.Crc < 0) { // so testing Zip will says its ok
WriteEncryptionHeader(entry.DosTime << 16);
} else {
WriteEncryptionHeader(entry.Crc);
}
}
}
