/**
* Ensure this is an ORC file to prevent users from trying to read text
* files or RC files as ORC files.
* @param in the file being read
* @param path the filename for error messages
* @param psLen the postscript length
* @param buffer the tail of the file
* @
*/
static void ensureOrcFooter(Stream @in,
string path,
int psLen,
ByteBuffer buffer)
{
int len = OrcFile.MAGIC.Length;
if (psLen < len + 1)
{
throw new FormatException("Malformed ORC file " + path +
". Invalid postscript length " + psLen);
}
int offset = buffer.arrayOffset() + buffer.position() + buffer.limit() - 1 - len;
byte[] array = buffer.array();
// now look for the magic string at the end of the postscript.
if (!Lists.AreEqual(array, offset, OrcFile.MAGIC, len))
{
// If it isn't there, this may be the 0.11.0 version of ORC.
// Read the first 3 bytes of the file to check for the header
byte[] header = new byte[len];
@in.readFully(0, header, 0, len);
// if it isn't there, this isn't an ORC file
if (!Lists.AreEqual(header, 0, OrcFile.MAGIC, len))
{
throw new FormatException("Malformed ORC file " + path +
". Invalid postscript.");
}
}
}