/// <summary>
/// Class constructor
/// </summary>
/// <param name="baseFile"></param>
/// <param name="list"></param>
/// <param name="bytesPerLine"Number of bytes to display per line.></param>
public BinaryDiffLines(Stream baseFile, AddCopyCollection list, int bytesPerLine)
{
this.bytesPerLine = bytesPerLine;
baseFile.Seek(0, SeekOrigin.Begin);
foreach (IAddCopy entry in list)
{
if (entry.IsAdd)
{
// Add A's bytes to VerLines
Addition add = (Addition)entry;
byte[] bytes = add.GetBytes();
int length = bytes.Length;
using (MemoryStream stream = new MemoryStream(bytes, false))
{
this.AddBytesFromStream(stream, 0, length, false, true);
}
// Move the ver position.
this.versionPosition += length;
}
else
{
Copy copy = (Copy)entry;
if (this.basePosition < copy.BaseOffset)
{
// Add bytes to BaseLines from this.iBasePos to C.iBaseOffset-1
int length = copy.BaseOffset - this.basePosition;
this.AddBytesFromStream(baseFile, this.basePosition, length, true, false);
this.basePosition += length;
}
// Add copied bytes to both sets of lines.
this.AddBytesFromStream(baseFile, copy.BaseOffset, copy.Length, true, true);
// Move the base and version positions.
this.basePosition = copy.BaseOffset + copy.Length;
this.versionPosition += copy.Length;
}
}
int baseLength = (int)baseFile.Length;
if (this.basePosition < baseLength)
{
// Add bytes to BaseLines from this.iBasePos to this.Base.Length
this.AddBytesFromStream(baseFile, this.basePosition, baseLength - this.basePosition, true, false);
}
}
/// <summary>
/// Does a binary diff on the two streams and returns an <see cref="AddCopyCollection"/>
/// of the differences.
/// </summary>
/// <param name="baseFile">The base file.</param>
/// <param name="versionFile">The version file.</param>
/// <returns>An AddCopyCollection that can be used later to construct the version file from the base file.</returns>
public AddCopyCollection Execute(Stream baseFile, Stream versionFile,
IDiffProgress progress)
{
if (!baseFile.CanSeek || !versionFile.CanSeek)
{
throw new ArgumentException("The Base and Version streams must support seeking.");
}
TableEntry[] table = new TableEntry[this.tableSize];
List <IAddCopy> list = new List <IAddCopy>();
AddCopyCollection result = new AddCopyCollection(list);
baseFile.Seek(0, SeekOrigin.Begin);
versionFile.Seek(0, SeekOrigin.End);
int verPos = 0;
int basePos = 0;
int verStart = 0;
bool isBaseActive = true;
uint verHash = 0;
uint baseHash = 0;
int lastVerHashPos = 0;
int lastBaseHashPos = 0;
while (verPos <= (versionFile.Length - this.footprintLength))
{
progress.Token.ThrowIfCancellationRequested();
// The GetTableEntry procedure will add the entry if it isn't already there.
// This gives us a default behavior of favoring the first match.
verHash = this.Footprint(versionFile, verPos, verHash, ref lastVerHashPos);
TableEntry verEntry = GetTableEntry(table, verHash, versionFile, verPos);
TableEntry baseEntry = null;
if (isBaseActive)
{
baseHash = this.Footprint(baseFile, basePos, baseHash, ref lastBaseHashPos);
baseEntry = GetTableEntry(table, baseHash, baseFile, basePos);
}
if (baseFile == verEntry.File && Verify(baseFile, verEntry.Offset, versionFile, verPos))
{
int length = this.EmitCodes(verEntry.Offset, verPos, verStart, baseFile, versionFile, list);
basePos = verEntry.Offset + length;
verPos += length;
verStart = verPos;
FlushTable(table);
continue;
}
else if (this.favorLastMatch)
{
verEntry.Offset = verPos;
verEntry.File = versionFile;
}
isBaseActive = isBaseActive && (basePos <= (baseFile.Length - this.footprintLength));
if (isBaseActive)
{
if (versionFile == baseEntry.File && Verify(versionFile, baseEntry.Offset, baseFile, basePos) &&
verStart <= baseEntry.Offset)
{
int length = this.EmitCodes(basePos, baseEntry.Offset, verStart, baseFile, versionFile, list);
verPos = baseEntry.Offset + length;
basePos += length;
verStart = verPos;
FlushTable(table);
continue;
}
else if (this.favorLastMatch)
{
baseEntry.Offset = basePos;
baseEntry.File = baseFile;
}
}
verPos++;
basePos++;
}
this.EmitCodes((int)baseFile.Length, (int)versionFile.Length, verStart, baseFile, versionFile, list);
Debug.Assert(
result.TotalByteLength == (int)versionFile.Length,
"The total byte length of the AddCopyCollection MUST equal the length of the version file!");
return(result);
}
