1 files changed, 143 insertions, 0 deletions
diff --git a/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/PGPCompressedData.java b/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/PGPCompressedData.java
new file mode 100644
index 000000000..36e684416
--- /dev/null
+++ b/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/PGPCompressedData.java
@@ -0,0 +1,143 @@
+package org.spongycastle.openpgp;
+
+import java.io.EOFException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.zip.Inflater;
+import java.util.zip.InflaterInputStream;
+
+import org.spongycastle.bcpg.BCPGInputStream;
+import org.spongycastle.bcpg.CompressedDataPacket;
+import org.spongycastle.bcpg.CompressionAlgorithmTags;
+import org.spongycastle.apache.bzip2.CBZip2InputStream;
+
+/**
+ * Compressed data objects.
+ */
+public class PGPCompressedData 
+    implements CompressionAlgorithmTags
+{
+    CompressedDataPacket    data;
+    
+    public PGPCompressedData(
+        BCPGInputStream    pIn)
+        throws IOException
+    {
+        data = (CompressedDataPacket)pIn.readPacket();
+    }
+    
+    /**
+     * Return the algorithm used for compression
+     * 
+     * @return algorithm code
+     */
+    public int getAlgorithm()
+    {
+        return data.getAlgorithm();
+    }
+    
+    /**
+     * Return the raw input stream contained in the object.
+     * 
+     * @return InputStream
+     */
+    public InputStream getInputStream()
+    {
+        return data.getInputStream();
+    }
+    
+    /**
+     * Return an uncompressed input stream which allows reading of the 
+     * compressed data.
+     * 
+     * @return InputStream
+     * @throws PGPException
+     */
+    public InputStream getDataStream()
+        throws PGPException
+    {
+      if (this.getAlgorithm() == UNCOMPRESSED)
+      {
+          return this.getInputStream();
+      }
+      if (this.getAlgorithm() == ZIP)
+      {
+          return new InflaterInputStream(this.getInputStream(), new Inflater(true)) 
+          {
+              // If the "nowrap" inflater option is used the stream can 
+              // apparently overread - we override fill() and provide
+              // an extra byte for the end of the input stream to get
+              // around this.
+              //
+              // Totally weird...
+              //
+              protected void fill() throws IOException
+              {
+                  if (eof)
+                  {
+                      throw new EOFException("Unexpected end of ZIP input stream");
+                  }
+                  
+                  len = this.in.read(buf, 0, buf.length);
+                  
+                  if (len == -1)
+                  {
+                      buf[0] = 0;
+                      len = 1;
+                      eof = true;
+                  }
+                  
+                  inf.setInput(buf, 0, len);
+              }
+
+              private boolean eof = false;
+          };
+      }
+      if (this.getAlgorithm() == ZLIB)
+      {
+          return new InflaterInputStream(this.getInputStream())
+          {
+              // If the "nowrap" inflater option is used the stream can 
+              // apparently overread - we override fill() and provide
+              // an extra byte for the end of the input stream to get
+              // around this.
+              //
+              // Totally weird...
+              //
+              protected void fill() throws IOException
+              {
+                  if (eof)
+                  {
+                      throw new EOFException("Unexpected end of ZIP input stream");
+                  }
+                  
+                  len = this.in.read(buf, 0, buf.length);
+                  
+                  if (len == -1)
+                  {
+                      buf[0] = 0;
+                      len = 1;
+                      eof = true;
+                  }
+
+                  inf.setInput(buf, 0, len);
+              }
+
+              private boolean eof = false;
+          };
+      }
+      if (this.getAlgorithm() == BZIP2)
+      {
+          try
+          {
+              return new CBZip2InputStream(this.getInputStream());
+          }
+          catch (IOException e)
+          {
+              throw new PGPException("I/O problem with stream: " + e, e);
+          }
+      }
+        
+      throw new PGPException("can't recognise compression algorithm: " + this.getAlgorithm());
+    }
+}