public unsafe static string Readlink(string path)
{
var pathBytes = Encoding.UTF8.GetBytes(path);
int bufferLength = 1024;
byte *buffer = stackalloc byte[bufferLength];
long size;
fixed(byte *pathname = pathBytes)
{
size = LibC.readlink(pathname, buffer, bufferLength);
if (size == -1)
{
PlatformException.Throw();
}
}
return(Encoding.UTF8.GetString(buffer, (int)size));
}
public override int ReadLink(ReadOnlySpan <byte> path, Span <byte> buffer, Guid fileGuid)
{
path = base.TransformPath(path);
if (debug)
{
Console.WriteLine($"NeoFS::ReadLink({RawDirs.HR(path)}");
}
ssize_t retl;
fixed(byte *b = buffer)
{
retl = LibC.readlink(toBp(path), b, buffer.Length);
}
if (retl < 0)
{
return(-LibC.errno);
}
return(0);
}
public override int GetAttr(ReadOnlySpan <byte> path, ref stat stat, FuseFileInfoRef fiRef, Guid fileGuid)
{
try
{
path = base.TransformPath(path);
if (debug)
{
Console.WriteLine($"NeoFS::GetAttr({RawDirs.HR(path)})");
fixed(stat *st = &stat)
{
var lc = LibC.lstat(toBp(path), st);
if (lc < 0)
{
// Windows file explorer hits lot of files that don't exist
//Console.WriteLine($"Stat error: {lc} errno={LibC.errno} path={RawDirs.HR(path)}");
return(-LibC.errno);
}
}
// Intercept an asset - we must provide the asset's Attr, not the link of the baked file
if ((stat.st_mode & LibC.S_IFMT) == LibC.S_IFLNK)
{
if (debug)
{
Console.WriteLine($"Link Seen: Stat mode={stat.st_mode}, S_IFMT={LibC.S_IFMT}, link={LibC.S_IFLNK}");
}
ssize_t retl;
var buffer = new byte[1024];
fixed(byte *b = buffer)
{
retl = LibC.readlink(toBp(path), b, buffer.Length);
}
// Trying to do something like startswith for bytes that's fast
var link = MemoryExtensions.AsSpan(buffer, 0, assetTag.Length);
if (debug)
{
Console.WriteLine($"NeoFS::GetAttr Asset Detected - ({RawDirs.HR(path)}, {RawDirs.HR(link)}");
}
if (link.SequenceEqual(assetTag))
{
link = MemoryExtensions.AsSpan(buffer, 0, (int)retl);
if (debug)
{
Console.WriteLine($"Found ASSET {RawDirs.HR(link)}");
}
base.GetAssetAttr(path, link, ref stat, fileGuid);
return(0);
}
}
if (debug)
{
Console.WriteLine($"Stat Dump: size={stat.st_size}, mode={stat.st_mode}, mtim={stat.st_mtim}");
}
return(0);
}
catch (Exception ex)
{
Console.WriteLine($"GetAttr error: {ex.Message} {ex.StackTrace}");
return(-LibC.ENOENT);
}
}
// File read
public override int Open(ReadOnlySpan <byte> path, ref FuseFileInfo fi, Guid fileGuid)
{
path = base.TransformPath(path);
if (path.Length < 1)
{
return(-LibC.ENOENT);
}
if (debug)
{
Console.WriteLine($"NeoFS::Open()");
}
// Stat the file
var stat = new stat();
var lc = LibC.lstat(toBp(path), &stat);
if (lc < 0)
{
return(-LibC.errno);
}
string extAssetSha1 = null;
// Intercept an asset - we must provide the asset's Attr, not the link of the baked file
if ((stat.st_mode & LibC.S_IFMT) == LibC.S_IFLNK)
{
if (debug)
{
Console.WriteLine($"Stat mode={stat.st_mode}, S_IFMT={LibC.S_IFMT}, link={LibC.S_IFLNK}");
}
// Get the link
ssize_t retl;
var buffer = new byte[1024];
fixed(byte *b = buffer)
{
retl = LibC.readlink(toBp(path), b, buffer.Length);
}
// Trying to do something like startswith for bytes that's fast
var link = MemoryExtensions.AsSpan <byte>(buffer, 0, assetTag.Length);
if (debug)
{
Console.WriteLine($"NeoFS::GetAttr Asset Detected - ({RawDirs.HR(path)}, {RawDirs.HR(link)}");
}
if (link.SequenceEqual(assetTag))
{
link = MemoryExtensions.AsSpan <byte>(buffer, 0, (int)retl);
if (debug)
{
Console.WriteLine($"Found ASSET {RawDirs.HR(link)}");
}
var asset = link.Slice(assetTag.Length);
extAssetSha1 = Encoding.ASCII.GetString(asset);
}
else
{
link = MemoryExtensions.AsSpan <byte>(buffer, 0, (int)retl);
//path = base.TransformPath() - have to figure out how to pass to our mountmapper
// Probably a dependancy injection
// These links shouldn't happen, but it would be a nice attack vector
}
}
// See if asset -- if so, set to asset mode and call base
if (extAssetSha1 != null) // Asset Mode
{
var fakeFd = LibC.open(toBp(fakeFile), 0);
if (fakeFd > 0)
{
fi.fh = (ulong)fakeFd;
FileContexts.Add(fi.fh, new FileContext
{
AssetLink = null,
ExtAssetSha1 = extAssetSha1,
ExtFileHandle = null,
});
//Console.WriteLine($"Create Context (sha1) ID={fi.fh}");
}
else
{
Console.WriteLine($"Error Opening /dev/null? Error={LibC.errno}");
}
return(base.AssetOpen(path, ref fi, fileGuid));
}
// transform the link
var newFd = LibC.open(toBp(path), fi.flags);
if (newFd > 0)
{
fi.fh = (ulong)newFd;
// Make a context anyway
FileContexts.Add(fi.fh, new FileContext
{
AssetLink = null,
ExtAssetSha1 = null,
ExtFileHandle = null,
});
//Console.WriteLine($"Create Context (null) ID={fi.fh}");
return(0);
}
return(-LibC.errno);
}