package org.bouncycastle.bcpg;
import java.io.*;
/**
* Basic output stream.
*/
public class BCPGOutputStream
extends OutputStream
implements PacketTags, CompressionAlgorithmTags
{
OutputStream out;
private byte[] partialBuffer;
private int partialBufferLength;
private int partialPower;
private int partialOffset;
private static final int BUF_SIZE_POWER = 16; // 2^16 size buffer on long files
public BCPGOutputStream(
OutputStream out)
{
this.out = out;
}
/**
* Create a stream representing an old style partial object.
*
* @param tag the packet tag for the object.
*/
public BCPGOutputStream(
OutputStream out,
int tag)
throws IOException
{
this.out = out;
this.writeHeader(tag, true, true, 0);
}
/**
* Create a stream representing a general packet.
*
* @param out
* @param tag
* @param length
* @param oldFormat
* @throws IOException
*/
public BCPGOutputStream(
OutputStream out,
int tag,
long length,
boolean oldFormat)
throws IOException
{
this.out = out;
if (length > 0xFFFFFFFFL)
{
this.writeHeader(tag, false, true, 0);
this.partialBufferLength = 1 << BUF_SIZE_POWER;
this.partialBuffer = new byte[partialBufferLength];
this.partialPower = BUF_SIZE_POWER;
this.partialOffset = 0;
}
else
{
this.writeHeader(tag, oldFormat, false, length);
}
}
/**
*
* @param tag
* @param length
* @throws IOException
*/
public BCPGOutputStream(
OutputStream out,
int tag,
long length)
throws IOException
{
this.out = out;
this.writeHeader(tag, false, false, length);
}
/**
* Create a new style partial input stream buffered into chunks.
*
* @param out output stream to write to.
* @param tag packet tag.
* @param buffer size of chunks making up the packet.
* @throws IOException
*/
public BCPGOutputStream(
OutputStream out,
int tag,
byte[] buffer)
throws IOException
{
this.out = out;
this.writeHeader(tag, false, true, 0);
this.partialBuffer = buffer;
int length = partialBuffer.length;
for (partialPower = 0; length != 1; partialPower++)
{
length >>>= 1;
}
if (partialPower > 30)
{
throw new IOException("Buffer cannot be greater than 2^30 in length.");
}
this.partialBufferLength = 1 << partialPower;
this.partialOffset = 0;
}
private void writeNewPacketLength(
long bodyLen)
throws IOException
{
if (bodyLen < 192)
{
out.write((byte)bodyLen);
}
else if (bodyLen <= 8383)
{
bodyLen -= 192;
out.write((byte)(((bodyLen >> 8) & 0xff) + 192));
out.write((byte)bodyLen);
}
else
{
out.write(0xff);
out.write((byte)(bodyLen >> 24));
out.write((byte)(bodyLen >> 16));
out.write((byte)(bodyLen >> 8));
out.write((byte)bodyLen);
}
}
private void writeHeader(
int tag,
boolean oldPackets,
boolean partial,
long bodyLen)
throws IOException
{
int hdr = 0x80;
if (partialBuffer != null)
{
partialFlush(true);
partialBuffer = null;
}
if (oldPackets)
{
hdr |= tag << 2;
if (partial)
{
this.write(hdr | 0x03);
}
else
{
if (bodyLen <= 0xff)
{
this.write(hdr);
this.write((byte)bodyLen);
}
else if (bodyLen <= 0xffff)
{
this.write(hdr | 0x01);
this.write((byte)(bodyLen >> 8));
this.write((byte)(bodyLen));
}
else
{
this.write(hdr | 0x02);
this.write((byte)(bodyLen >> 24));
this.write((byte)(bodyLen >> 16));
this.write((byte)(bodyLen >> 8));
this.write((byte)bodyLen);
}
}
}
else
{
hdr |= 0x40 | tag;
this.write(hdr);
if (partial)
{
partialOffset = 0;
}
else
{
this.writeNewPacketLength(bodyLen);
}
}
}
private void partialFlush(
boolean isLast)
throws IOException
{
if (isLast)
{
writeNewPacketLength(partialOffset);
out.write(partialBuffer, 0, partialOffset);
}
else
{
out.write(0xE0 | partialPower);
out.write(partialBuffer, 0, partialBufferLength);
}
partialOffset = 0;
}
private void writePartial(
byte b)
throws IOException
{
if (partialOffset == partialBufferLength)
{
partialFlush(false);
}
partialBuffer[partialOffset++] = b;
}
private void writePartial(
byte[] buf,
int off,
int len)
throws IOException
{
if (partialOffset == partialBufferLength)
{
partialFlush(false);
}
if (len <= (partialBufferLength - partialOffset))
{
System.arraycopy(buf, off, partialBuffer, partialOffset, len);
partialOffset += len;
}
else
{
System.arraycopy(buf, off, partialBuffer, partialOffset, partialBufferLength - partialOffset);
off += partialBufferLength - partialOffset;
len -= partialBufferLength - partialOffset;
partialFlush(false);
while (len > partialBufferLength)
{
System.arraycopy(buf, off, partialBuffer, 0, partialBufferLength);
off += partialBufferLength;
len -= partialBufferLength;
partialFlush(false);
}
System.arraycopy(buf, off, partialBuffer, 0, len);
partialOffset += len;
}
}
public void write(
int b)
throws IOException
{
if (partialBuffer != null)
{
writePartial((byte)b);
}
else
{
out.write(b);
}
}
public void write(
byte[] bytes,
int off,
int len)
throws IOException
{
if (partialBuffer != null)
{
writePartial(bytes, off, len);
}
else
{
out.write(bytes, off, len);
}
}
public void writePacket(
ContainedPacket p)
throws IOException
{
p.encode(this);
}
void writePacket(
int tag,
byte[] body,
boolean oldFormat)
throws IOException
{
this.writeHeader(tag, oldFormat, false, body.length);
this.write(body);
}
public void writeObject(
BCPGObject o)
throws IOException
{
o.encode(this);
}
/**
* Flush the underlying stream.
*/
public void flush()
throws IOException
{
out.flush();
}
/**
* Finish writing out the current packet without closing the underlying stream.
*/
public void finish()
throws IOException
{
if (partialBuffer != null)
{
partialFlush(true);
partialBuffer = null;
}
}
public void close()
throws IOException
{
this.finish();
out.flush();
out.close();
}
}