/**
* Parse a signature from a byte stream
*
* @param in input bytes to parse
* @return the decoded signature data
* @throws CtxException
*/
static ScalaSig parse(byte[] in) throws CtxException {
ByteArrayInputStream bis = new ByteArrayInputStream(in);
// Pull version info & check OK
int major = Nat.read(bis);
int minor = Nat.read(bis);
if (major != 5 || minor != 0) {
throw new CtxException("Unexpected signature version found: " + major + "." + minor);
}
// Pull table
int tblEntries = Nat.read(bis);
Table table = new Table();
for (int e = 0; e < tblEntries; e++) {
int type = Nat.read(bis);
int size = Nat.read(bis);
byte[] raw = new byte[size];
if (bis.read(raw, 0, size) != size) {
throw new CtxException("Unexpected EOF in signature data");
}
table.addEntry(type, raw);
}
// The input stream should be consumed at this point but a 'feature' of the encoding is
// that there may be a trailer 0 byte, just check all look good
int trail = bis.read();
if (trail == 0) trail = bis.read();
if (trail != -1) throw new CtxException("Unexpected additional byte found at end of signature");
// All good so create signature
return new ScalaSig(major, minor, table);
}
/**
* Decode from raw bytes
*
* @param raw the bytes
*/
ExtModClassRefEntry(byte[] raw) {
ByteArrayInputStream in = new ByteArrayInputStream(raw);
_nameRef = Nat.read(in);
// Symbol is optional in the encoding
_symbolRef = -1;
if (in.available() > 0) {
_symbolRef = Nat.read(in);
}
}
/**
* Get a byte array containing the encoded signature
*
* @return the byte array
*/
byte[] asBytes() {
try {
ByteArrayOutputStream out = new ByteArrayOutputStream();
Nat.write(_majorVersion, out);
Nat.write(_minorVersion, out);
_table.write(out);
return out.toByteArray();
} catch (IOException e) {
throw new CtxException("Unexpected error converting signature to byte array", e);
}
}
/**
* Write entry back to a stream
*
* @param bos stream to write to
* @throws IOException
*/
public void write(ByteArrayOutputStream bos) throws IOException {
Nat.write(TblTypeID.EXT_MOD_CLASS_REF_ID, bos);
if (_symbolRef != -1) {
Nat.write(Nat.size(_nameRef) + Nat.size(_symbolRef), bos);
Nat.write(_nameRef, bos);
Nat.write(_symbolRef, bos);
} else {
Nat.write(Nat.size(_nameRef), bos);
Nat.write(_nameRef, bos);
}
}
/**
* Write the table as a byte stream
*
* @param out the stream to write to
* @throws IOException
*/
void write(ByteArrayOutputStream out) throws IOException {
Nat.write(entries.size(), out);
for (TableEntry e : entries) {
e.write(out);
}
}
/**
* Write entry back to a stream
*
* @param bos stream to write to
* @throws IOException
*/
public void write(ByteArrayOutputStream bos) throws IOException {
Nat.write(TblTypeID.TERM_NAME_ID, bos);
byte[] bytes = _name.getBytes(StandardCharsets.UTF_8);
Nat.write(bytes.length, bos);
bos.write(bytes);
}
/**
* Write entry back to a stream
*
* @param bos stream to write to
* @throws IOException
*/
public void write(ByteArrayOutputStream bos) throws IOException {
Nat.write(type, bos);
Nat.write(raw.length, bos);
bos.write(raw);
}
