// Write the local file header
void WriteLocalHeader(ZipEntry entry, EntryPatchData patchData)
{
CompressionMethod method = entry.CompressionMethod;
bool headerInfoAvailable = true; // How to get this?
bool patchEntryHeader = false;
WriteLEInt(ZipConstants.LocalHeaderSignature);
WriteLEShort(entry.Version);
WriteLEShort(entry.Flags);
WriteLEShort((byte)method);
WriteLEInt((int)entry.DosTime);
if (headerInfoAvailable == true)
{
WriteLEInt((int)entry.Crc);
if (entry.LocalHeaderRequiresZip64)
{
WriteLEInt(-1);
WriteLEInt(-1);
}
else
{
WriteLEInt(entry.IsCrypted ? (int)entry.CompressedSize + ZipConstants.CryptoHeaderSize : (int)entry.CompressedSize);
WriteLEInt((int)entry.Size);
}
}
else
{
if (patchData != null)
{
patchData.CrcPatchOffset = stream_.Position;
}
WriteLEInt(0); // Crc
if (patchData != null)
{
patchData.SizePatchOffset = stream_.Position;
}
// For local header both sizes appear in Zip64 Extended Information
if (entry.LocalHeaderRequiresZip64 && patchEntryHeader)
{
WriteLEInt(-1);
WriteLEInt(-1);
}
else
{
WriteLEInt(0); // Compressed size
WriteLEInt(0); // Uncompressed size
}
}
byte[] name = ZipConstants.ConvertToArray(entry.Flags, entry.Name);
if (name.Length > 0xFFFF)
{
throw new ZipException("Entry name too long.");
}
ZipExtraData ed = new ZipExtraData(entry.ExtraData);
if (entry.LocalHeaderRequiresZip64 && (headerInfoAvailable || patchEntryHeader))
{
ed.StartNewEntry();
if (headerInfoAvailable)
{
ed.AddLeLong(entry.Size);
ed.AddLeLong(entry.CompressedSize);
}
else
{
ed.AddLeLong(-1);
ed.AddLeLong(-1);
}
ed.AddNewEntry(1);
if (!ed.Find(1))
{
throw new ZipException("Internal error cant find extra data");
}
if (patchData != null)
{
patchData.SizePatchOffset = ed.CurrentReadIndex;
}
}
else
{
ed.Delete(1);
}
byte[] extra = ed.GetEntryData();
WriteLEShort(name.Length);
WriteLEShort(extra.Length);
if (name.Length > 0)
{
stream_.Write(name, 0, name.Length);
}
if (entry.LocalHeaderRequiresZip64 && patchEntryHeader)
{
patchData.SizePatchOffset += stream_.Position;
}
if (extra.Length > 0)
{
stream_.Write(extra, 0, extra.Length);
}
}
/// <summary>
/// Process extra data fields updating the entry based on the contents.
/// </summary>
/// <param name="localHeader">True if the extra data fields should be handled
/// for a local header, rather than for a central header.
/// </param>
internal void ProcessExtraData(bool localHeader)
{
ZipExtraData extraData = new ZipExtraData(this.extra);
if ( extraData.Find(0x0001) ) {
if ( (versionToExtract & 0xff) < ZipConstants.VersionZip64 ) {
throw new ZipException("Zip64 Extended information found but version is not valid");
}
// The recorded size will change but remember that this is zip64.
forceZip64_ = true;
if ( extraData.ValueLength < 4 ) {
throw new ZipException("Extra data extended Zip64 information length is invalid");
}
if ( localHeader || (size == uint.MaxValue) ) {
size = (ulong)extraData.ReadLong();
}
if ( localHeader || (compressedSize == uint.MaxValue) ) {
compressedSize = (ulong)extraData.ReadLong();
}
if ( !localHeader && (offset == uint.MaxValue) ) {
offset = extraData.ReadLong();
}
}
else {
if (
((versionToExtract & 0xff) >= ZipConstants.VersionZip64) &&
((size == uint.MaxValue) || (compressedSize == uint.MaxValue))
) {
throw new ZipException("Zip64 Extended information required but is missing.");
}
}
if ( extraData.Find(10) ) {
// No room for any tags.
if ( extraData.ValueLength < 8 ) {
throw new ZipException("NTFS Extra data invalid");
}
extraData.ReadInt(); // Reserved
while ( extraData.UnreadCount >= 4 ) {
int ntfsTag = extraData.ReadShort();
int ntfsLength = extraData.ReadShort();
if ( ntfsTag == 1 ) {
if ( ntfsLength >= 24 ) {
long lastModification = extraData.ReadLong();
long lastAccess = extraData.ReadLong();
long createTime = extraData.ReadLong();
DateTime = System.DateTime.FromFileTime(lastModification);
}
break;
}
else {
// An unknown NTFS tag so simply skip it.
extraData.Skip(ntfsLength);
}
}
}
else if ( extraData.Find(0x5455) ) {
int length = extraData.ValueLength;
int flags = extraData.ReadByte();
// Can include other times but these are ignored. Length of data should
// actually be 1 + 4 * no of bits in flags.
if ( ((flags & 1) != 0) && (length >= 5) ) {
int iTime = extraData.ReadInt();
DateTime = (new System.DateTime ( 1970, 1, 1, 0, 0, 0 ).ToUniversalTime() +
new TimeSpan ( 0, 0, 0, iTime, 0 )).ToLocalTime();
}
}
}