static FileIDResult Test_UNIF(IdentifyJob job)
{
if (!CheckMagic(job.Stream, SimpleMagics.UNIF))
{
return(new FileIDResult());
}
//TODO - simple parser (for starters, check for a known chunk being next, see http://wiki.nesdev.com/w/index.php/UNIF)
var ret = new FileIDResult(FileIDType.UNIF, 100);
return(ret);
}
static FileIDResult Test_Simple(IdentifyJob job, FileIDType type, SimpleMagicRecord magic)
{
var ret = new FileIDResult(type);
if (CheckMagic(job.Stream, magic))
{
return(new FileIDResult(type, 100));
}
else
{
return(new FileIDResult());
}
}
static FileIDResult Test_INES(IdentifyJob job)
{
if (!CheckMagic(job.Stream, SimpleMagics.INES))
{
return(new FileIDResult());
}
var ret = new FileIDResult(FileIDType.INES, 100);
//an INES file should be a multiple of 8k, with the 16 byte header.
//if it isnt.. this is fishy.
if (((job.Stream.Length - 16) & (8 * 1024 - 1)) != 0)
{
ret.Confidence = 50;
}
return(ret);
}
static FileIDResult Test_N64(IdentifyJob job)
{
// .Z64 = No swapping
// .N64 = Word Swapped
// .V64 = Byte Swapped
//not sure how to check for these yet...
var ret = new FileIDResult(FileIDType.N64, 5);
if (job.Extension == "V64")
{
ret.ExtraInfo["byteswap"] = true;
}
if (job.Extension == "N64")
{
ret.ExtraInfo["wordswap"] = true;
}
return(ret);
}
static FileIDResult Test_GB_GBC(IdentifyJob job)
{
if (!CheckMagic(job.Stream, SimpleMagics.GB))
{
return(new FileIDResult());
}
var ret = new FileIDResult(FileIDType.GB, 100);
int type = ReadByte(job.Stream, 0x143);
if ((type & 0x80) != 0)
{
ret.FileIDType = FileIDType.GBC;
}
//could check cart type and rom size for extra info if necessary
return(ret);
}
static FileIDResult Test_BIN_ISO(IdentifyJob job)
{
//ok, this is complicated.
//there are lots of mislabeled bins/isos so lets just treat them the same (mostly)
//if the BIN cant be recognized, but it is small, it is more likely some other rom BIN than a disc (turbocd or other)
if (job.Extension == "BIN")
{
//first we can check for SMD magic words.
//since this extension is ambiguous, we can't be completely sure about it. but it's almost surely accurate
if (CheckMagic(job.Stream, SimpleMagics.SEGAGENESIS))
{
var ret = new FileIDResult(FileIDType.SMD, 95);
ret.ExtraInfo["type"] = "genesis";
return(ret);
}
if (CheckMagic(job.Stream, SimpleMagics.SEGAMEGADRIVE))
{
var ret = new FileIDResult(FileIDType.SMD, 95);
ret.ExtraInfo["type"] = "megadrive";
}
}
//well... guess it's a disc.
//since it's just a bin, we dont need the user to provide a DiscSystem disc.
//lets just analyze this as best we can.
//of course, it's a lot of redundant logic with the discsystem disc checker.
//but you kind of need different approaches when loading a hugely unstructured bin file
//discsystem won't really even be happy mounting a .bin anyway, and we don't want it to be
//for PSX, we have a magic word to look for.
//it's at 0x24E0 with a mode2 (2352 byte) track 1.
//what if its 2048 byte?
//i found a ".iso" which was actually 2352 byte sectors..
//found a hilarious ".bin.iso" which was actually 2352 byte sectors
//so, I think it's possible that every valid PSX disc is mode2 in the track 1
if (CheckMagic(job.Stream, SimpleMagics.PSX))
{
var ret = new FileIDResult(FileIDType.PSX, 95);
//this is an unreliable way to get a PSX game!
ret.ExtraInfo["unreliable"] = true;
return(ret);
}
//it's not proven that this is reliable. this is actually part of the Mode 1 CDFS header. perhaps it's mobile?
//if it's mobile, we'll need to mount it as an ISO file here via discsystem
if (CheckMagic(job.Stream, SimpleMagics.PSP))
{
return(new FileIDResult(FileIDType.PSP, 95));
}
//if this was an ISO, we might discover the magic word at offset 0...
//if it was a mode2/2352 bin, we might discover it at offset 16 (after the data sector header)
if (CheckMagic(job.Stream, SimpleMagics.SEGASATURN, 0))
{
return(new FileIDResult(FileIDType.Saturn, job.Extension == "ISO" ? 95 : 90));
}
if (CheckMagic(job.Stream, SimpleMagics.SEGASATURN, 16))
{
return(new FileIDResult(FileIDType.Saturn, job.Extension == "BIN" ? 95 : 90));
}
if (CheckMagic(job.Stream, SimpleMagics.SEGADISCSYSTEM, 0))
{
return(new FileIDResult(FileIDType.MegaCD, job.Extension == "ISO" ? 95 : 90));
}
if (CheckMagic(job.Stream, SimpleMagics.SEGADISCSYSTEM, 16))
{
return(new FileIDResult(FileIDType.MegaCD, job.Extension == "BIN" ? 95 : 90));
}
if (job.Extension == "ISO")
{
return(new FileIDResult(FileIDType.Disc, 1));
}
else
{
return(new FileIDResult(FileIDType.Multiple, 1));
}
}
/// <summary>
/// performs wise heuristics to identify a file.
/// this will attempt to return early if a confident result can be produced.
/// </summary>
public FileIDResults Identify(IdentifyParams p)
{
IdentifyJob job = new IdentifyJob()
{
Stream = p.SeekableStream,
Disc = p.Disc
};
//if we have a disc, that's a separate codepath
if (job.Disc != null)
{
return(IdentifyDisc(job));
}
FileIDResults ret = new FileIDResults();
string ext = p.Extension;
if (ext != null)
{
ext = ext.TrimStart('.').ToUpper();
job.Extension = ext;
}
if (job.Extension == "CUE")
{
ret.ShouldTryDisc = true;
return(ret);
}
if (job.Extension != null)
{
//first test everything associated with this extension
ExtensionInfo handler = null;
if (ExtensionHandlers.TryGetValue(ext, out handler))
{
foreach (var del in handler.Testers)
{
var fidr = del(job);
if (fidr.FileIDType == FileIDType.None)
{
continue;
}
ret.Add(fidr);
}
ret.Sort();
//add a low confidence result just based on extension, if it doesnt exist
if (ret.Find((x) => x.FileIDType == handler.DefaultForExtension) == null)
{
var fidr = new FileIDResult(handler.DefaultForExtension, 5);
ret.Add(fidr);
}
}
}
ret.Sort();
//if we didnt find anything high confidence, try all the testers (TODO)
return(ret);
}
