chovy-sign/CHOVY-JUAN/PathTable.cs

100 lines
3.5 KiB
C#

//
// Copyright (c) 2008-2011, Kenneth Bell
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//
using System;
using System.Collections.Generic;
using System.Text;
using DiscUtils.Streams;
namespace DiscUtils.Iso9660
{
internal class PathTable : BuilderExtent
{
private readonly bool _byteSwap;
private readonly List<BuildDirectoryInfo> _dirs;
private readonly Encoding _enc;
private readonly Dictionary<BuildDirectoryMember, uint> _locations;
private byte[] _readCache;
public PathTable(bool byteSwap, Encoding enc, List<BuildDirectoryInfo> dirs,
Dictionary<BuildDirectoryMember, uint> locations, long start)
: base(start, CalcLength(enc, dirs))
{
_byteSwap = byteSwap;
_enc = enc;
_dirs = dirs;
_locations = locations;
}
public override void Dispose() {}
public override void PrepareForRead()
{
_readCache = new byte[Length];
int pos = 0;
List<BuildDirectoryInfo> sortedList = new List<BuildDirectoryInfo>(_dirs);
sortedList.Sort(BuildDirectoryInfo.PathTableSortComparison);
Dictionary<BuildDirectoryInfo, ushort> dirNumbers = new Dictionary<BuildDirectoryInfo, ushort>(_dirs.Count);
ushort i = 1;
foreach (BuildDirectoryInfo di in sortedList)
{
dirNumbers[di] = i++;
PathTableRecord ptr = new PathTableRecord();
ptr.DirectoryIdentifier = di.PickName(null, _enc);
ptr.LocationOfExtent = _locations[di];
ptr.ParentDirectoryNumber = dirNumbers[di.Parent];
pos += ptr.Write(_byteSwap, _enc, _readCache, pos);
}
}
public override int Read(long diskOffset, byte[] buffer, int offset, int count)
{
long relPos = diskOffset - Start;
int numRead = (int)Math.Min(count, _readCache.Length - relPos);
Array.Copy(_readCache, (int)relPos, buffer, offset, numRead);
return numRead;
}
public override void DisposeReadState()
{
_readCache = null;
}
private static uint CalcLength(Encoding enc, List<BuildDirectoryInfo> dirs)
{
uint length = 0;
foreach (BuildDirectoryInfo di in dirs)
{
length += di.GetPathTableEntrySize(enc);
}
return length;
}
}
}