/Common/SharpZipLib/Zip/ZipExtraData.cs
C# | 984 lines | 554 code | 106 blank | 324 comment | 64 complexity | c3922d77c6746802b32d1ae2aa4f6aad MD5 | raw file
- //
- // ZipExtraData.cs
- //
- // Copyright 2004-2007 John Reilly
- //
- // This program is free software; you can redistribute it and/or
- // modify it under the terms of the GNU General Public License
- // as published by the Free Software Foundation; either version 2
- // of the License, or (at your option) any later version.
- //
- // This program is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
- //
- // You should have received a copy of the GNU General Public License
- // along with this program; if not, write to the Free Software
- // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- //
- // Linking this library statically or dynamically with other modules is
- // making a combined work based on this library. Thus, the terms and
- // conditions of the GNU General Public License cover the whole
- // combination.
- //
- // As a special exception, the copyright holders of this library give you
- // permission to link this library with independent modules to produce an
- // executable, regardless of the license terms of these independent
- // modules, and to copy and distribute the resulting executable under
- // terms of your choice, provided that you also meet, for each linked
- // independent module, the terms and conditions of the license of that
- // module. An independent module is a module which is not derived from
- // or based on this library. If you modify this library, you may extend
- // this exception to your version of the library, but you are not
- // obligated to do so. If you do not wish to do so, delete this
- // exception statement from your version.
-
- using System;
- using System.Collections;
- using System.IO;
-
- namespace SharpZipLib.Zip
- {
- // TODO: Sort out wether tagged data is useful and what a good implementation might look like.
- // Its just a sketch of an idea at the moment.
-
- /// <summary>
- /// ExtraData tagged value interface.
- /// </summary>
- public interface ITaggedData
- {
- /// <summary>
- /// Get the ID for this tagged data value.
- /// </summary>
- short TagID { get; }
-
- /// <summary>
- /// Set the contents of this instance from the data passed.
- /// </summary>
- /// <param name="data">The data to extract contents from.</param>
- /// <param name="offset">The offset to begin extracting data from.</param>
- /// <param name="count">The number of bytes to extract.</param>
- void SetData(byte[] data, int offset, int count);
-
- /// <summary>
- /// Get the data representing this instance.
- /// </summary>
- /// <returns>Returns the data for this instance.</returns>
- byte[] GetData();
- }
-
- /// <summary>
- /// A raw binary tagged value
- /// </summary>
- public class RawTaggedData : ITaggedData
- {
- /// <summary>
- /// Initialise a new instance.
- /// </summary>
- /// <param name="tag">The tag ID.</param>
- public RawTaggedData(short tag)
- {
- tag_ = tag;
- }
-
- #region ITaggedData Members
-
- /// <summary>
- /// Get the ID for this tagged data value.
- /// </summary>
- public short TagID
- {
- get { return tag_; }
- set { tag_ = value; }
- }
-
- /// <summary>
- /// Set the data from the raw values provided.
- /// </summary>
- /// <param name="data">The raw data to extract values from.</param>
- /// <param name="offset">The index to start extracting values from.</param>
- /// <param name="count">The number of bytes available.</param>
- public void SetData(byte[] data, int offset, int count)
- {
- if( data==null )
- {
- throw new ArgumentNullException("data");
- }
-
- data_=new byte[count];
- Array.Copy(data, offset, data_, 0, count);
- }
-
- /// <summary>
- /// Get the binary data representing this instance.
- /// </summary>
- /// <returns>The raw binary data representing this instance.</returns>
- public byte[] GetData()
- {
- return data_;
- }
-
- #endregion
-
- /// <summary>
- /// Get /set the binary data representing this instance.
- /// </summary>
- /// <returns>The raw binary data representing this instance.</returns>
- public byte[] Data
- {
- get { return data_; }
- set { data_=value; }
- }
-
- #region Instance Fields
- /// <summary>
- /// The tag ID for this instance.
- /// </summary>
- protected short tag_;
-
- byte[] data_;
- #endregion
- }
-
- /// <summary>
- /// Class representing extended unix date time values.
- /// </summary>
- public class ExtendedUnixData : ITaggedData
- {
- /// <summary>
- /// Flags indicate which values are included in this instance.
- /// </summary>
- [Flags]
- public enum Flags : byte
- {
- /// <summary>
- /// The modification time is included
- /// </summary>
- ModificationTime = 0x01,
-
- /// <summary>
- /// The access time is included
- /// </summary>
- AccessTime = 0x02,
-
- /// <summary>
- /// The create time is included.
- /// </summary>
- CreateTime = 0x04,
- }
-
- #region ITaggedData Members
-
- /// <summary>
- /// Get the ID
- /// </summary>
- public short TagID
- {
- get { return 0x5455; }
- }
-
- /// <summary>
- /// Set the data from the raw values provided.
- /// </summary>
- /// <param name="data">The raw data to extract values from.</param>
- /// <param name="index">The index to start extracting values from.</param>
- /// <param name="count">The number of bytes available.</param>
- public void SetData(byte[] data, int index, int count)
- {
- using (MemoryStream ms = new MemoryStream(data, index, count, false))
- using (ZipHelperStream helperStream = new ZipHelperStream(ms))
- {
- // bit 0 if set, modification time is present
- // bit 1 if set, access time is present
- // bit 2 if set, creation time is present
-
- flags_ = (Flags)helperStream.ReadByte();
- if (((flags_ & Flags.ModificationTime) != 0) && (count >= 5))
- {
- int iTime = helperStream.ReadLEInt();
-
- modificationTime_ = (new System.DateTime(1970, 1, 1, 0, 0, 0).ToUniversalTime() +
- new TimeSpan(0, 0, 0, iTime, 0)).ToLocalTime();
- }
-
- if ((flags_ & Flags.AccessTime) != 0)
- {
- int iTime = helperStream.ReadLEInt();
-
- lastAccessTime_ = (new System.DateTime(1970, 1, 1, 0, 0, 0).ToUniversalTime() +
- new TimeSpan(0, 0, 0, iTime, 0)).ToLocalTime();
- }
-
- if ((flags_ & Flags.CreateTime) != 0)
- {
- int iTime = helperStream.ReadLEInt();
-
- createTime_ = (new System.DateTime(1970, 1, 1, 0, 0, 0).ToUniversalTime() +
- new TimeSpan(0, 0, 0, iTime, 0)).ToLocalTime();
- }
- }
- }
-
- /// <summary>
- /// Get the binary data representing this instance.
- /// </summary>
- /// <returns>The raw binary data representing this instance.</returns>
- public byte[] GetData()
- {
- using (MemoryStream ms = new MemoryStream())
- using (ZipHelperStream helperStream = new ZipHelperStream(ms))
- {
- helperStream.IsStreamOwner = false;
- helperStream.WriteByte((byte)flags_); // Flags
- if ( (flags_ & Flags.ModificationTime) != 0) {
- TimeSpan span = modificationTime_.ToUniversalTime() - new System.DateTime(1970, 1, 1, 0, 0, 0).ToUniversalTime();
- int seconds = (int)span.TotalSeconds;
- helperStream.WriteLEInt(seconds);
- }
- if ( (flags_ & Flags.AccessTime) != 0) {
- TimeSpan span = lastAccessTime_.ToUniversalTime() - new System.DateTime(1970, 1, 1, 0, 0, 0).ToUniversalTime();
- int seconds = (int)span.TotalSeconds;
- helperStream.WriteLEInt(seconds);
- }
- if ( (flags_ & Flags.CreateTime) != 0) {
- TimeSpan span = createTime_.ToUniversalTime() - new System.DateTime(1970, 1, 1, 0, 0, 0).ToUniversalTime();
- int seconds = (int)span.TotalSeconds;
- helperStream.WriteLEInt(seconds);
- }
- return ms.ToArray();
- }
- }
-
- #endregion
-
- /// <summary>
- /// Test a <see cref="DateTime"> value to see if is valid and can be represented here.</see>
- /// </summary>
- /// <param name="value">The <see cref="DateTime">value</see> to test.</param>
- /// <returns>Returns true if the value is valid and can be represented; false if not.</returns>
- /// <remarks>The standard Unix time is a signed integer data type, directly encoding the Unix time number,
- /// which is the number of seconds since 1970-01-01.
- /// Being 32 bits means the values here cover a range of about 136 years.
- /// The minimum representable time is 1901-12-13 20:45:52,
- /// and the maximum representable time is 2038-01-19 03:14:07.
- /// </remarks>
- public static bool IsValidValue(DateTime value)
- {
- return (( value >= new DateTime(1901, 12, 13, 20, 45, 52)) ||
- ( value <= new DateTime(2038, 1, 19, 03, 14, 07) ));
- }
-
- /// <summary>
- /// Get /set the Modification Time
- /// </summary>
- /// <exception cref="ArgumentOutOfRangeException"></exception>
- /// <seealso cref="IsValidValue"></seealso>
- public DateTime ModificationTime
- {
- get { return modificationTime_; }
- set
- {
- if ( !IsValidValue(value) ) {
- throw new ArgumentOutOfRangeException("value");
- }
-
- flags_ |= Flags.ModificationTime;
- modificationTime_=value;
- }
- }
-
- /// <summary>
- /// Get / set the Access Time
- /// </summary>
- /// <exception cref="ArgumentOutOfRangeException"></exception>
- /// <seealso cref="IsValidValue"></seealso>
- public DateTime AccessTime
- {
- get { return lastAccessTime_; }
- set {
- if ( !IsValidValue(value) ) {
- throw new ArgumentOutOfRangeException("value");
- }
-
- flags_ |= Flags.AccessTime;
- lastAccessTime_=value;
- }
- }
-
- /// <summary>
- /// Get / Set the Create Time
- /// </summary>
- /// <exception cref="ArgumentOutOfRangeException"></exception>
- /// <seealso cref="IsValidValue"></seealso>
- public DateTime CreateTime
- {
- get { return createTime_; }
- set {
- if ( !IsValidValue(value) ) {
- throw new ArgumentOutOfRangeException("value");
- }
-
- flags_ |= Flags.CreateTime;
- createTime_=value;
- }
- }
-
- /// <summary>
- /// Get/set the <see cref="Flags">values</see> to include.
- /// </summary>
- Flags Include
- {
- get { return flags_; }
- set { flags_ = value; }
- }
-
- #region Instance Fields
- Flags flags_;
- DateTime modificationTime_ = new DateTime(1970,1,1);
- DateTime lastAccessTime_ = new DateTime(1970, 1, 1);
- DateTime createTime_ = new DateTime(1970, 1, 1);
- #endregion
- }
-
- /// <summary>
- /// Class handling NT date time values.
- /// </summary>
- public class NTTaggedData : ITaggedData
- {
- /// <summary>
- /// Get the ID for this tagged data value.
- /// </summary>
- public short TagID
- {
- get { return 10; }
- }
-
- /// <summary>
- /// Set the data from the raw values provided.
- /// </summary>
- /// <param name="data">The raw data to extract values from.</param>
- /// <param name="index">The index to start extracting values from.</param>
- /// <param name="count">The number of bytes available.</param>
- public void SetData(byte[] data, int index, int count)
- {
- using (MemoryStream ms = new MemoryStream(data, index, count, false))
- using (ZipHelperStream helperStream = new ZipHelperStream(ms))
- {
- helperStream.ReadLEInt(); // Reserved
- while (helperStream.Position < helperStream.Length)
- {
- int ntfsTag = helperStream.ReadLEShort();
- int ntfsLength = helperStream.ReadLEShort();
- if (ntfsTag == 1)
- {
- if (ntfsLength >= 24)
- {
- long lastModificationTicks = helperStream.ReadLELong();
- lastModificationTime_ = DateTime.FromFileTime(lastModificationTicks);
-
- long lastAccessTicks = helperStream.ReadLELong();
- lastAccessTime_ = DateTime.FromFileTime(lastAccessTicks);
-
- long createTimeTicks = helperStream.ReadLELong();
- createTime_ = DateTime.FromFileTime(createTimeTicks);
- }
- break;
- }
- else
- {
- // An unknown NTFS tag so simply skip it.
- helperStream.Seek(ntfsLength, SeekOrigin.Current);
- }
- }
- }
- }
-
- /// <summary>
- /// Get the binary data representing this instance.
- /// </summary>
- /// <returns>The raw binary data representing this instance.</returns>
- public byte[] GetData()
- {
- using (MemoryStream ms = new MemoryStream())
- using (ZipHelperStream helperStream = new ZipHelperStream(ms))
- {
- helperStream.IsStreamOwner = false;
- helperStream.WriteLEInt(0); // Reserved
- helperStream.WriteLEShort(1); // Tag
- helperStream.WriteLEShort(24); // Length = 3 x 8.
- helperStream.WriteLELong(lastModificationTime_.ToFileTime());
- helperStream.WriteLELong(lastAccessTime_.ToFileTime());
- helperStream.WriteLELong(createTime_.ToFileTime());
- return ms.ToArray();
- }
- }
-
- /// <summary>
- /// Test a <see cref="DateTime"> valuie to see if is valid and can be represented here.</see>
- /// </summary>
- /// <param name="value">The <see cref="DateTime">value</see> to test.</param>
- /// <returns>Returns true if the value is valid and can be represented; false if not.</returns>
- /// <remarks>
- /// NTFS filetimes are 64-bit unsigned integers, stored in Intel
- /// (least significant byte first) byte order. They determine the
- /// number of 1.0E-07 seconds (1/10th microseconds!) past WinNT "epoch",
- /// which is "01-Jan-1601 00:00:00 UTC". 28 May 60056 is the upper limit
- /// </remarks>
- public static bool IsValidValue(DateTime value)
- {
- bool result = true;
- try
- {
- value.ToFileTimeUtc();
- }
- catch
- {
- result = false;
- }
- return result;
- }
-
- /// <summary>
- /// Get/set the <see cref="DateTime">last modification time</see>.
- /// </summary>
- public DateTime LastModificationTime
- {
- get { return lastModificationTime_; }
- set {
- if (! IsValidValue(value))
- {
- throw new ArgumentOutOfRangeException("value");
- }
- lastModificationTime_ = value;
- }
- }
-
- /// <summary>
- /// Get /set the <see cref="DateTime">create time</see>
- /// </summary>
- public DateTime CreateTime
- {
- get { return createTime_; }
- set {
- if ( !IsValidValue(value)) {
- throw new ArgumentOutOfRangeException("value");
- }
- createTime_ = value;
- }
- }
-
- /// <summary>
- /// Get /set the <see cref="DateTime">last access time</see>.
- /// </summary>
- public DateTime LastAccessTime
- {
- get { return lastAccessTime_; }
- set {
- if (!IsValidValue(value)) {
- throw new ArgumentOutOfRangeException("value");
- }
- lastAccessTime_ = value;
- }
- }
-
- #region Instance Fields
- DateTime lastAccessTime_ = DateTime.FromFileTime(0);
- DateTime lastModificationTime_ = DateTime.FromFileTime(0);
- DateTime createTime_ = DateTime.FromFileTime(0);
- #endregion
- }
-
- /// <summary>
- /// A factory that creates <see cref="ITaggedData">tagged data</see> instances.
- /// </summary>
- interface ITaggedDataFactory
- {
- /// <summary>
- /// Get data for a specific tag value.
- /// </summary>
- /// <param name="tag">The tag ID to find.</param>
- /// <param name="data">The data to search.</param>
- /// <param name="offset">The offset to begin extracting data from.</param>
- /// <param name="count">The number of bytes to extract.</param>
- /// <returns>The located <see cref="ITaggedData">value found</see>, or null if not found.</returns>
- ITaggedData Create(short tag, byte[] data, int offset, int count);
- }
-
- ///
- /// <summary>
- /// A class to handle the extra data field for Zip entries
- /// </summary>
- /// <remarks>
- /// Extra data contains 0 or more values each prefixed by a header tag and length.
- /// They contain zero or more bytes of actual data.
- /// The data is held internally using a copy on write strategy. This is more efficient but
- /// means that for extra data created by passing in data can have the values modified by the caller
- /// in some circumstances.
- /// </remarks>
- sealed public class ZipExtraData : IDisposable
- {
- #region Constructors
- /// <summary>
- /// Initialise a default instance.
- /// </summary>
- public ZipExtraData()
- {
- Clear();
- }
-
- /// <summary>
- /// Initialise with known extra data.
- /// </summary>
- /// <param name="data">The extra data.</param>
- public ZipExtraData(byte[] data)
- {
- if ( data == null )
- {
- data_ = new byte[0];
- }
- else
- {
- data_ = data;
- }
- }
- #endregion
-
- /// <summary>
- /// Get the raw extra data value
- /// </summary>
- /// <returns>Returns the raw byte[] extra data this instance represents.</returns>
- public byte[] GetEntryData()
- {
- if ( Length > ushort.MaxValue ) {
- throw new ZipException("Data exceeds maximum length");
- }
-
- return (byte[])data_.Clone();
- }
-
- /// <summary>
- /// Clear the stored data.
- /// </summary>
- public void Clear()
- {
- if ( (data_ == null) || (data_.Length != 0) ) {
- data_ = new byte[0];
- }
- }
-
- /// <summary>
- /// Gets the current extra data length.
- /// </summary>
- public int Length
- {
- get { return data_.Length; }
- }
-
- /// <summary>
- /// Get a read-only <see cref="Stream"/> for the associated tag.
- /// </summary>
- /// <param name="tag">The tag to locate data for.</param>
- /// <returns>Returns a <see cref="Stream"/> containing tag data or null if no tag was found.</returns>
- public Stream GetStreamForTag(int tag)
- {
- Stream result = null;
- if ( Find(tag) ) {
- result = new MemoryStream(data_, index_, readValueLength_, false);
- }
- return result;
- }
-
- /// <summary>
- /// Get the <see cref="ITaggedData">tagged data</see> for a tag.
- /// </summary>
- /// <param name="tag">The tag to search for.</param>
- /// <returns>Returns a <see cref="ITaggedData">tagged value</see> or null if none found.</returns>
- private ITaggedData GetData(short tag)
- {
- ITaggedData result = null;
- if (Find(tag))
- {
- result = Create(tag, data_, readValueStart_, readValueLength_);
- }
- return result;
- }
-
- static ITaggedData Create(short tag, byte[] data, int offset, int count)
- {
- ITaggedData result = null;
- switch ( tag )
- {
- case 0x000A:
- result = new NTTaggedData();
- break;
- case 0x5455:
- result = new ExtendedUnixData();
- break;
- default:
- result = new RawTaggedData(tag);
- break;
- }
- result.SetData(data, offset, count);
- return result;
- }
-
- /// <summary>
- /// Get the length of the last value found by <see cref="Find"/>
- /// </summary>
- /// <remarks>This is only valid if <see cref="Find"/> has previously returned true.</remarks>
- public int ValueLength
- {
- get { return readValueLength_; }
- }
-
- /// <summary>
- /// Get the index for the current read value.
- /// </summary>
- /// <remarks>This is only valid if <see cref="Find"/> has previously returned true.
- /// Initially the result will be the index of the first byte of actual data. The value is updated after calls to
- /// <see cref="ReadInt"/>, <see cref="ReadShort"/> and <see cref="ReadLong"/>. </remarks>
- public int CurrentReadIndex
- {
- get { return index_; }
- }
-
- /// <summary>
- /// Get the number of bytes remaining to be read for the current value;
- /// </summary>
- public int UnreadCount
- {
- get
- {
- if ((readValueStart_ > data_.Length) ||
- (readValueStart_ < 4) ) {
- throw new ZipException("Find must be called before calling a Read method");
- }
-
- return readValueStart_ + readValueLength_ - index_;
- }
- }
-
- /// <summary>
- /// Find an extra data value
- /// </summary>
- /// <param name="headerID">The identifier for the value to find.</param>
- /// <returns>Returns true if the value was found; false otherwise.</returns>
- public bool Find(int headerID)
- {
- readValueStart_ = data_.Length;
- readValueLength_ = 0;
- index_ = 0;
-
- int localLength = readValueStart_;
- int localTag = headerID - 1;
-
- // Trailing bytes that cant make up an entry (as there arent enough
- // bytes for a tag and length) are ignored!
- while ( (localTag != headerID) && (index_ < data_.Length - 3) ) {
- localTag = ReadShortInternal();
- localLength = ReadShortInternal();
- if ( localTag != headerID ) {
- index_ += localLength;
- }
- }
-
- bool result = (localTag == headerID) && ((index_ + localLength) <= data_.Length);
-
- if ( result ) {
- readValueStart_ = index_;
- readValueLength_ = localLength;
- }
-
- return result;
- }
-
- /// <summary>
- /// Add a new entry to extra data.
- /// </summary>
- /// <param name="taggedData">The <see cref="ITaggedData"/> value to add.</param>
- public void AddEntry(ITaggedData taggedData)
- {
- if (taggedData == null)
- {
- throw new ArgumentNullException("taggedData");
- }
- AddEntry(taggedData.TagID, taggedData.GetData());
- }
-
- /// <summary>
- /// Add a new entry to extra data
- /// </summary>
- /// <param name="headerID">The ID for this entry.</param>
- /// <param name="fieldData">The data to add.</param>
- /// <remarks>If the ID already exists its contents are replaced.</remarks>
- public void AddEntry(int headerID, byte[] fieldData)
- {
- if ( (headerID > ushort.MaxValue) || (headerID < 0)) {
- throw new ArgumentOutOfRangeException("headerID");
- }
-
- int addLength = (fieldData == null) ? 0 : fieldData.Length;
-
- if ( addLength > ushort.MaxValue ) {
- #if NETCF_1_0
- throw new ArgumentOutOfRangeException("fieldData");
- #else
- throw new ArgumentOutOfRangeException("fieldData", "exceeds maximum length");
- #endif
- }
-
- // Test for new length before adjusting data.
- int newLength = data_.Length + addLength + 4;
-
- if ( Find(headerID) )
- {
- newLength -= (ValueLength + 4);
- }
-
- if ( newLength > ushort.MaxValue ) {
- throw new ZipException("Data exceeds maximum length");
- }
-
- Delete(headerID);
-
- byte[] newData = new byte[newLength];
- data_.CopyTo(newData, 0);
- int index = data_.Length;
- data_ = newData;
- SetShort(ref index, headerID);
- SetShort(ref index, addLength);
- if ( fieldData != null ) {
- fieldData.CopyTo(newData, index);
- }
- }
-
- /// <summary>
- /// Start adding a new entry.
- /// </summary>
- /// <remarks>Add data using <see cref="AddData(byte[])"/>, <see cref="AddLeShort"/>, <see cref="AddLeInt"/>, or <see cref="AddLeLong"/>.
- /// The new entry is completed and actually added by calling <see cref="AddNewEntry"/></remarks>
- /// <seealso cref="AddEntry(ITaggedData)"/>
- public void StartNewEntry()
- {
- newEntry_ = new MemoryStream();
- }
-
- /// <summary>
- /// Add entry data added since <see cref="StartNewEntry"/> using the ID passed.
- /// </summary>
- /// <param name="headerID">The identifier to use for this entry.</param>
- public void AddNewEntry(int headerID)
- {
- byte[] newData = newEntry_.ToArray();
- newEntry_ = null;
- AddEntry(headerID, newData);
- }
-
- /// <summary>
- /// Add a byte of data to the pending new entry.
- /// </summary>
- /// <param name="data">The byte to add.</param>
- /// <seealso cref="StartNewEntry"/>
- public void AddData(byte data)
- {
- newEntry_.WriteByte(data);
- }
-
- /// <summary>
- /// Add data to a pending new entry.
- /// </summary>
- /// <param name="data">The data to add.</param>
- /// <seealso cref="StartNewEntry"/>
- public void AddData(byte[] data)
- {
- if ( data == null ) {
- throw new ArgumentNullException("data");
- }
-
- newEntry_.Write(data, 0, data.Length);
- }
-
- /// <summary>
- /// Add a short value in little endian order to the pending new entry.
- /// </summary>
- /// <param name="toAdd">The data to add.</param>
- /// <seealso cref="StartNewEntry"/>
- public void AddLeShort(int toAdd)
- {
- unchecked {
- newEntry_.WriteByte(( byte )toAdd);
- newEntry_.WriteByte(( byte )(toAdd >> 8));
- }
- }
-
- /// <summary>
- /// Add an integer value in little endian order to the pending new entry.
- /// </summary>
- /// <param name="toAdd">The data to add.</param>
- /// <seealso cref="StartNewEntry"/>
- public void AddLeInt(int toAdd)
- {
- unchecked {
- AddLeShort(( short )toAdd);
- AddLeShort(( short )(toAdd >> 16));
- }
- }
-
- /// <summary>
- /// Add a long value in little endian order to the pending new entry.
- /// </summary>
- /// <param name="toAdd">The data to add.</param>
- /// <seealso cref="StartNewEntry"/>
- public void AddLeLong(long toAdd)
- {
- unchecked {
- AddLeInt(( int )(toAdd & 0xffffffff));
- AddLeInt(( int )(toAdd >> 32));
- }
- }
-
- /// <summary>
- /// Delete an extra data field.
- /// </summary>
- /// <param name="headerID">The identifier of the field to delete.</param>
- /// <returns>Returns true if the field was found and deleted.</returns>
- public bool Delete(int headerID)
- {
- bool result = false;
-
- if ( Find(headerID) ) {
- result = true;
- int trueStart = readValueStart_ - 4;
-
- byte[] newData = new byte[data_.Length - (ValueLength + 4)];
- Array.Copy(data_, 0, newData, 0, trueStart);
-
- int trueEnd = trueStart + ValueLength + 4;
- Array.Copy(data_, trueEnd, newData, trueStart, data_.Length - trueEnd);
- data_ = newData;
- }
- return result;
- }
-
- #region Reading Support
- /// <summary>
- /// Read a long in little endian form from the last <see cref="Find">found</see> data value
- /// </summary>
- /// <returns>Returns the long value read.</returns>
- public long ReadLong()
- {
- ReadCheck(8);
- return (ReadInt() & 0xffffffff) | ((( long )ReadInt()) << 32);
- }
-
- /// <summary>
- /// Read an integer in little endian form from the last <see cref="Find">found</see> data value.
- /// </summary>
- /// <returns>Returns the integer read.</returns>
- public int ReadInt()
- {
- ReadCheck(4);
-
- int result = data_[index_] + (data_[index_ + 1] << 8) +
- (data_[index_ + 2] << 16) + (data_[index_ + 3] << 24);
- index_ += 4;
- return result;
- }
-
- /// <summary>
- /// Read a short value in little endian form from the last <see cref="Find">found</see> data value.
- /// </summary>
- /// <returns>Returns the short value read.</returns>
- public int ReadShort()
- {
- ReadCheck(2);
- int result = data_[index_] + (data_[index_ + 1] << 8);
- index_ += 2;
- return result;
- }
-
- /// <summary>
- /// Read a byte from an extra data
- /// </summary>
- /// <returns>The byte value read or -1 if the end of data has been reached.</returns>
- public int ReadByte()
- {
- int result = -1;
- if ( (index_ < data_.Length) && (readValueStart_ + readValueLength_ > index_) ) {
- result = data_[index_];
- index_ += 1;
- }
- return result;
- }
-
- /// <summary>
- /// Skip data during reading.
- /// </summary>
- /// <param name="amount">The number of bytes to skip.</param>
- public void Skip(int amount)
- {
- ReadCheck(amount);
- index_ += amount;
- }
-
- void ReadCheck(int length)
- {
- if ((readValueStart_ > data_.Length) ||
- (readValueStart_ < 4) ) {
- throw new ZipException("Find must be called before calling a Read method");
- }
-
- if (index_ > readValueStart_ + readValueLength_ - length ) {
- throw new ZipException("End of extra data");
- }
- }
-
- /// <summary>
- /// Internal form of <see cref="ReadShort"/> that reads data at any location.
- /// </summary>
- /// <returns>Returns the short value read.</returns>
- int ReadShortInternal()
- {
- if ( index_ > data_.Length - 2) {
- throw new ZipException("End of extra data");
- }
-
- int result = data_[index_] + (data_[index_ + 1] << 8);
- index_ += 2;
- return result;
- }
-
- void SetShort(ref int index, int source)
- {
- data_[index] = (byte)source;
- data_[index + 1] = (byte)(source >> 8);
- index += 2;
- }
-
- #endregion
-
- #region IDisposable Members
-
- /// <summary>
- /// Dispose of this instance.
- /// </summary>
- public void Dispose()
- {
- if ( newEntry_ != null ) {
- newEntry_.Close();
- }
- }
-
- #endregion
-
- #region Instance Fields
- int index_;
- int readValueStart_;
- int readValueLength_;
-
- MemoryStream newEntry_;
- byte[] data_;
- #endregion
- }
- }