/// <summary>
/// Read the next entry from the zip file.
/// </summary>
///
/// <remarks>
/// <para>
/// Call this method just before calling <see cref="Read(byte[], int, int)"/>,
/// to position the pointer in the zip file to the next entry that can be
/// read. Subsequent calls to <c>Read()</c>, will decrypt and decompress the
/// data in the zip file, until <c>Read()</c> returns 0.
/// </para>
///
/// <para>
/// Each time you call <c>GetNextEntry()</c>, the pointer in the wrapped
/// stream is moved to the next entry in the zip file. If you call <see
/// cref="Seek(long, SeekOrigin)"/>, and thus re-position the pointer within
/// the file, you will need to call <c>GetNextEntry()</c> again, to insure
/// that the file pointer is positioned at the beginning of a zip entry.
/// </para>
///
/// <para>
/// This method returns the <c>ZipEntry</c>. Using a stream approach, you will
/// read the raw bytes for an entry in a zip file via calls to <c>Read()</c>.
/// Alternatively, you can extract an entry into a file, or a stream, by
/// calling <see cref="ZipEntry.Extract()"/>, or one of its siblings.
/// </para>
///
/// </remarks>
///
/// <returns>
/// The <c>ZipEntry</c> read. Returns null (or Nothing in VB) if there are no more
/// entries in the zip file.
/// </returns>
///
public ZipEntry GetNextEntry()
{
if (_findRequired)
{
// find the next signature
long d = SharedUtilities.FindSignature(_inputStream, ZipConstants.ZipEntrySignature);
if (d == -1)
{
return(null);
}
// back up 4 bytes: ReadEntry assumes the file pointer is positioned before the entry signature
_inputStream.Seek(-4, SeekOrigin.Current);
// workitem 10178
CDEngine.CDUtils.Zlib.SharedUtilities.Workaround_Ladybug318918(_inputStream);
}
// workitem 10923
else if (_firstEntry)
{
// we've already read one entry.
// Seek to the end of it.
_inputStream.Seek(_endOfEntry, SeekOrigin.Begin);
CDEngine.CDUtils.Zlib.SharedUtilities.Workaround_Ladybug318918(_inputStream);
}
_currentEntry = ZipEntry.ReadEntry(_container, !_firstEntry);
// ReadEntry leaves the file position after all the entry
// data and the optional bit-3 data descriptpr. This is
// where the next entry would normally start.
_endOfEntry = _inputStream.Position;
_firstEntry = true;
_needSetup = true;
_findRequired = false;
return(_currentEntry);
}
// build the TOC by reading each entry in the file.
private static void ReadIntoInstance_Orig(ZipFile zf)
{
zf.OnReadStarted();
//zf._entries = new System.Collections.Generic.List<ZipEntry>();
zf._entries = new System.Collections.Generic.Dictionary <String, ZipEntry>();
ZipEntry e;
if (zf.Verbose)
{
if (zf.Name == null)
{
zf.StatusMessageTextWriter.WriteLine("Reading zip from stream...");
}
else
{
zf.StatusMessageTextWriter.WriteLine("Reading zip {0}...", zf.Name);
}
}
// work item 6647: PK00 (packed to removable disk)
bool firstEntry = true;
ZipContainer zc = new ZipContainer(zf);
while ((e = ZipEntry.ReadEntry(zc, firstEntry)) != null)
{
if (zf.Verbose)
{
zf.StatusMessageTextWriter.WriteLine(" {0}", e.FileName);
}
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);
if (zf.Verbose && !String.IsNullOrEmpty(zf.Comment))
{
zf.StatusMessageTextWriter.WriteLine("Zip file Comment: {0}", zf.Comment);
}
}
catch (Exception) { }
zf.OnReadCompleted();
}