[FileTransfer] Log stack traces on error, some OOM handling

Try smaller buffers for uploading on OOM errors.
Log error reason instead of just sending to peer, and also
print a stack trace if applicable.

3 files changed, 43 insertions, 8 deletions

diff --git a/src/main/java/org/openslx/filetransfer/Downloader.java b/src/main/java/org/openslx/filetransfer/Downloader.java
index 13bd95c..b2dbbd1 100644
--- a/src/main/java/org/openslx/filetransfer/Downloader.java
+++ b/src/main/java/org/openslx/filetransfer/Downloader.java
@@ -116,6 +116,7 @@ public class Downloader extends Transfer
 				compressed += compressedLength;
 				uncompressed += decompressedLength;
 				if ( decompressedLength > len ) {
+					// TODO: Partial reads with buffering, if remote payload is larger than our buffer
 					throw new RuntimeException( "This should never happen! ;)" );
 				}
 				if ( decompressedLength == compressedLength ) {
@@ -168,6 +169,19 @@ public class Downloader extends Transfer
 		}
 		FileRange requestedRange;
 		try {
+			byte[] incoming = new byte[ 500000 ];
+			/* TODO once the Lz4InputStream can handle small buffer sizes / partial reads
+			for ( int bufsiz = 600; bufsiz >= 100 && incoming == null; bufsiz -= 100 ) {
+				try {
+					incoming = new byte[ bufsiz * 1024 ];
+				} catch ( OutOfMemoryError e ) {
+				}
+			}
+			if ( incoming == null ) {
+				log.error( "Could not allocate buffer for receiving." );
+				return false;
+			}
+			*/
 			while ( ( requestedRange = rangeCallback.get() ) != null ) {
 				if ( requestedRange.startOffset < 0 || requestedRange.startOffset >= requestedRange.endOffset ) {
 					log.error( "Callback supplied bad range (" + requestedRange.startOffset + " to " + requestedRange.endOffset + ")" );
@@ -197,7 +211,6 @@ public class Downloader extends Transfer
 				int chunkLength = requestedRange.getLength();
 				// If the uploader sets the COMPRESS field, assume compressed chunk
 				InputStream inStream = meta.peerWantsCompression() ? compressedIn : dataFromServer;
-				byte[] incoming = new byte[ 500000 ]; // 500kb
 				int hasRead = 0;
 				while ( hasRead < chunkLength ) {
 					int ret;
@@ -208,7 +221,7 @@ public class Downloader extends Transfer
 							return false;
 						}
 					} catch ( IOException e ) {
-						log.error( "Could not read payload from socket" );
+						log.error( "Could not read payload from socket", e );
 						sendErrorCode( "payload read error" );
 						return false;
 					}
diff --git a/src/main/java/org/openslx/filetransfer/Transfer.java b/src/main/java/org/openslx/filetransfer/Transfer.java
index c396d6e..933e63e 100644
--- a/src/main/java/org/openslx/filetransfer/Transfer.java
+++ b/src/main/java/org/openslx/filetransfer/Transfer.java
@@ -219,11 +219,17 @@ public abstract class Transfer
 	 */
 	protected void close( String error, UploadStatusCallback callback, boolean sendToPeer )
 	{
+		close( error, callback, sendToPeer, null );
+	}
+
+	protected void close( String error, UploadStatusCallback callback, boolean sendToPeer, Exception e )
+	{
 		if ( error != null ) {
 			if ( sendToPeer )
 				sendErrorCode( error );
 			if ( callback != null )
 				callback.uploadError( error );
+			log.info( "Closing with error '" + error + "'", e );
 		}
 		synchronized ( transferSocket ) {
 			safeClose( dataFromServer, outStream, transferSocket );
@@ -232,7 +238,12 @@ public abstract class Transfer
 
 	protected void close( String error )
 	{
-		close( error, null, false );
+		close( error, null );
+	}
+
+	protected void close( String error, Exception e )
+	{
+		close( error, null, false, e );
 	}
 
 	public void cancel()
diff --git a/src/main/java/org/openslx/filetransfer/Uploader.java b/src/main/java/org/openslx/filetransfer/Uploader.java
index 73445aa..ed6e972 100644
--- a/src/main/java/org/openslx/filetransfer/Uploader.java
+++ b/src/main/java/org/openslx/filetransfer/Uploader.java
@@ -136,6 +136,18 @@ public class Uploader extends Transfer
 				this.close( "Could not open given file for reading.", callback, true );
 				return false;
 			}
+			byte[] data = null;
+			// Cannot go above 500000 for backwards compat
+			for ( int bufsiz = 500; bufsiz >= 100 && data == null; bufsiz -= 100 ) {
+				try {
+					data = new byte[ bufsiz * 1000 ];
+				} catch ( OutOfMemoryError e ) {
+				}
+			}
+			if ( data == null ) {
+				this.close( "Could not allocate buffer for reading.", callback, true );
+				return false;
+			}
 			while ( !Thread.currentThread().isInterrupted() ) { // Loop as long as remote peer is requesting chunks from this file
 				// Read meta data of remote peer - either new range, or it's telling us it's done
 				MetaData meta = readMetaData();
@@ -158,14 +170,14 @@ public class Uploader extends Transfer
 						return false;
 					}
 				} catch ( IOException e ) {
-					this.close( "Could not get current length of file " + filename, callback, false );
+					this.close( "Could not get current length of file " + filename, callback, false, e );
 					return false;
 				}
 				// Seek to requested chunk
 				try {
 					file.seek( requestedRange.startOffset );
 				} catch ( IOException e ) {
-					this.close( "Could not seek to start of requested range in given file (" + requestedRange.startOffset + ")", callback, true );
+					this.close( "Could not seek to start of requested range in given file (" + requestedRange.startOffset + ")", callback, true, e );
 					return false;
 				}
 				// Send confirmation of range and compression mode we're about to send
@@ -185,7 +197,6 @@ public class Uploader extends Transfer
 					return false;
 				}
 				// Finally send requested chunk
-				byte[] data = new byte[ 500000 ]; // 500kb
 				int hasRead = 0;
 				int length = requestedRange.getLength();
 				while ( hasRead < length ) {
@@ -193,7 +204,7 @@ public class Uploader extends Transfer
 					try {
 						ret = file.read( data, 0, Math.min( length - hasRead, data.length ) );
 					} catch ( IOException e ) {
-						this.close( "Error reading from file ", callback, true );
+						this.close( "Error reading from file ", callback, true, e );
 						return false;
 					}
 					if ( ret == -1 ) {
@@ -204,7 +215,7 @@ public class Uploader extends Transfer
 					try {
 						outStr.write( data, 0, ret );
 					} catch ( IOException e ) {
-						this.close( "Sending payload failed" );
+						this.close( "Sending payload failed", e );
 						return false;
 					}
 					if ( callback != null )