public static InArchiveFormat CheckSignature(string fileName)
{
using (FileStream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
{
try
{
return(FileChecker.CheckSignature((Stream)fileStream));
}
catch (ArgumentException ex)
{
return(Formats.FormatByFileName(fileName, true));
}
}
}
private void Init(string archiveFullName)
{
this._FileName = archiveFullName;
this._Format = FileChecker.CheckSignature(archiveFullName);
SevenZipLibraryManager.LoadLibrary((object)this, (Enum)this._Format);
try
{
this._Archive = SevenZipLibraryManager.InArchive(this._Format, (object)this);
}
catch (SevenZipLibraryException ex)
{
SevenZipLibraryManager.FreeLibrary((object)this, (Enum)this._Format);
throw;
}
}
private void Init(Stream stream)
{
SevenZipExtractor.ValidateStream(stream);
this._Format = FileChecker.CheckSignature(stream);
SevenZipLibraryManager.LoadLibrary((object)this, (Enum)this._Format);
try
{
this._InStream = stream;
this._Archive = SevenZipLibraryManager.InArchive(this._Format, (object)this);
this._PackedSize = new long?(stream.Length);
}
catch (SevenZipLibraryException ex)
{
SevenZipLibraryManager.FreeLibrary((object)this, (Enum)this._Format);
throw;
}
}
public static InArchiveFormat CheckSignature(Stream stream)
{
if (!stream.CanRead)
{
throw new ArgumentException("The stream must be readable.");
}
if (stream.Length < 16L)
{
throw new ArgumentException("The stream is invalid.");
}
byte[] buffer = new byte[16];
int count = 16;
int offset = 0;
stream.Seek(0L, SeekOrigin.Begin);
while (count > 0)
{
int num = stream.Read(buffer, offset, count);
count -= num;
offset += num;
}
string str = BitConverter.ToString(buffer);
foreach (string key in Formats.InSignatureFormats.Keys)
{
if (str.StartsWith(key, StringComparison.OrdinalIgnoreCase) || str.Substring(6).StartsWith(key, StringComparison.OrdinalIgnoreCase) && Formats.InSignatureFormats[key] == InArchiveFormat.Lzh)
{
return(Formats.InSignatureFormats[key]);
}
}
try
{
FileChecker.SpecialDetect(stream, 257, InArchiveFormat.Tar);
}
catch (ArgumentException ex)
{
}
if (FileChecker.SpecialDetect(stream, 32769, InArchiveFormat.Iso) || FileChecker.SpecialDetect(stream, 34817, InArchiveFormat.Iso) || FileChecker.SpecialDetect(stream, 36865, InArchiveFormat.Iso))
{
return(InArchiveFormat.Iso);
}
throw new ArgumentException("The stream is invalid or no corresponding signature was found.");
}