public FileReversePart(PatchPart part)
{
this.Part = part;
}
public void Build()
{
List <FileReversePart> preReverse = new List <FileReversePart>();
using (FileStream fs = new FileStream(patchFileName, FileMode.Open, FileAccess.Read))
{
fs.Position = 18;
InflateStream stream = new InflateStream(fs, true);
WzPatcherReader reader = new WzPatcherReader(stream);
PatchPart filePart;
PatchPart reversePart;
while ((filePart = reader.ReadPart()) != null)
{
switch (filePart.Type)
{
case PatchType.Create:
if (filePart.FileLength > 0)
{
stream.Seek(filePart.FileLength, SeekOrigin.Current);
//在原文件夹寻找同名文件
string oldFile = Path.Combine(msDir, filePart.FileName);
if (File.Exists(oldFile))
{
reversePart = new PatchPart()
{
Type = PatchType.Create
};
reversePart.FileName = filePart.FileName;
reversePart.FileLength = (int)new FileInfo(oldFile).Length;
preReverse.Add(new FileReversePart(reversePart));
}
else
{
reversePart = new PatchPart()
{
Type = PatchType.Delete
};
reversePart.FileName = filePart.FileName;
preReverse.Add(new FileReversePart(reversePart));
}
}
break;
case PatchType.Rebuild:
reversePart = new PatchPart()
{
Type = PatchType.Rebuild,
OldChecksum = filePart.Checksum,
Checksum = filePart.OldChecksum,
FileName = filePart.FileName
};
List <FileReverseInst> instList = new List <FileReverseInst>();
BuildInstruction inst;
int filePos = 0;
while ((inst = reader.ReadInst()).Type != null)
{
if (inst.Type == BuildType.Ending)
{
break;
}
switch (inst.Type)
{
case BuildType.FromPatcher:
stream.Seek(inst.Length, SeekOrigin.Current);
break;
case BuildType.FillBytes:
break;
case BuildType.FromOldFile:
instList.Add(new FileReverseInst()
{
Inst = inst, NewFilePosition = filePos
});
break;
}
filePos += inst.Length;
}
preReverse.Add(new FileReversePart(reversePart)
{
InstList = instList
});
break;
case PatchType.Delete:
{
string oldFile = Path.Combine(msDir, filePart.FileName);
if (File.Exists(oldFile))
{
reversePart = new PatchPart()
{
Type = PatchType.Create
};
reversePart.FileName = filePart.FileName;
reversePart.FileLength = (int)new FileInfo(oldFile).Length;
preReverse.Add(new FileReversePart(reversePart));
}
}
break;
}
} //end while
} //end using
preReverse.Sort();
using (FileStream dest = new FileStream(outputFileName, FileMode.Create))
{
WzPatcherWriter writer = new WzPatcherWriter(dest);
writer.Begin();
foreach (var part in preReverse)
{
string oldFileName = Path.Combine(msDir, part.Part.FileName);
switch (part.Part.Type)
{
case PatchType.Create:
//计算hash copy文件
using (FileStream oldFs = new FileStream(oldFileName, FileMode.Open, FileAccess.Read, FileShare.Read))
{
part.Part.FileLength = (int)oldFs.Length;
part.Part.Checksum = CheckSum.ComputeHash(oldFs, part.Part.FileLength);
oldFs.Position = 0;
writer.WritePart(part.Part);
writer.WriteContent(oldFs, part.Part.FileLength);
}
break;
case PatchType.Rebuild:
writer.WritePart(part.Part);
using (FileStream oldFs = new FileStream(oldFileName, FileMode.Open, FileAccess.Read, FileShare.Read))
{
//计算指令
var instList = Work(part.InstList, (int)oldFs.Length);
//开始执行
foreach (var inst in instList)
{
switch (inst.Inst.Type)
{
case BuildType.FromOldFile: //参数反转
inst.Inst.OldFilePosition = inst.NewFilePosition;
writer.WriteInst(inst.Inst);
break;
case BuildType.FromPatcher: //go 待优化
writer.WriteInst(inst.Inst);
oldFs.Position = inst.NewFilePosition;
writer.WriteContent(oldFs, inst.Inst.Length);
break;
}
}
//结束执行
writer.WriteInst(new BuildInstruction(BuildType.Ending));
}
break;
case PatchType.Delete:
writer.WritePart(part.Part);
break;
}
}
writer.End();
}
}
