Revert "m"

This reverts commit 2a6c43d.

Author: Lucas McDonald

src/main/java/software/amazon/encryption/s3/internal/CipherSubscriber.java

@@ -20,6 +20,7 @@ public class CipherSubscriber implements Subscriber<ByteBuffer> {
     private final Long contentLength;
     private boolean isLastPart;
     private int tagLength;
+    private boolean onCompleteCalled = false;
 
     private byte[] outputBuffer;
 
@@ -47,16 +48,33 @@ public class CipherSubscriber implements Subscriber<ByteBuffer> {
 
     @Override
     public void onSubscribe(Subscription s) {
-        wrappedSubscriber.onSubscribe(s);
+        System.out.println("[CipherSubscriber] onSubscribe called with subscription: " + s);
+        wrappedSubscriber.onSubscribe(new Subscription() {
+            @Override
+            public void request(long n) {
+                System.out.println("[CipherSubscriber] Request received for " + n + " items");
+                s.request(n);
+            }
+
+            @Override
+            public void cancel() {
+                System.out.println("[CipherSubscriber] Subscription cancelled");
+                s.cancel();
+            }
+        });
     }
 
     @Override
     public void onNext(ByteBuffer byteBuffer) {
+        System.out.println("[CipherSubscriber] onNext called with buffer size: " + byteBuffer.remaining() + ", contentRead: " + contentRead.get() + ", contentLength: " + contentLength);
         int amountToReadFromByteBuffer = getAmountToReadFromByteBuffer(byteBuffer);
+        System.out.println("[CipherSubscriber] Amount to read from buffer: " + amountToReadFromByteBuffer);
 
         if (amountToReadFromByteBuffer > 0) {
             byte[] buf = BinaryUtils.copyBytesFrom(byteBuffer, amountToReadFromByteBuffer);
+            System.out.println("[CipherSubscriber] Copied " + buf.length + " bytes from input buffer");
             outputBuffer = cipher.update(buf, 0, amountToReadFromByteBuffer);
+            System.out.println("[CipherSubscriber] Cipher update produced " + (outputBuffer != null ? outputBuffer.length : 0) + " bytes");
 
             if (outputBuffer == null || outputBuffer.length == 0) {
                 // The underlying data is too short to fill in the block cipher.
@@ -65,12 +83,14 @@ public void onNext(ByteBuffer byteBuffer) {
                 // null OR length == 0.
                 if (contentRead.get() + tagLength >= contentLength) {
                     // All content has been read, so complete to get the final bytes
+                    System.out.println("[CipherSubscriber] All content read (" + contentRead.get() + " bytes), proceeding to finalBytes");
                     finalBytes();
                     return;
                 }
                 // Otherwise, wait for more bytes. To avoid blocking,
                 // send an empty buffer to the wrapped subscriber.
-                wrappedSubscriber.onNext(ByteBuffer.allocate(0));
+                System.out.println("[CipherSubscriber] Sending empty buffer to wrapped subscriber");
+//                wrappedSubscriber.onNext(ByteBuffer.allocate(0));
             } else {
                 // Check if stream has read all expected content.
                 // Once all content has been read, call onComplete.
@@ -89,19 +109,23 @@ public void onNext(ByteBuffer byteBuffer) {
                 // including the result of cipher.doFinal(), if applicable.
                 // Calling `wrappedSubscriber.onNext` more than once for `request(1)` 
                 // violates the Reactive Streams specification and can cause exceptions downstream.
+                System.out.println("[CipherSubscriber] Checking content read threshold: contentRead=" + contentRead.get() + ", tagLength=" + tagLength + ", contentLength=" + contentLength);
                 if (contentRead.get() + tagLength >= contentLength) {
                     // All content has been read; complete the stream.
                     // (Signalling onComplete from here is Reactive Streams-spec compliant;
                     // this class is allowed to call onComplete, even if upstream has not yet signaled onComplete.)
+                    System.out.println("[CipherSubscriber] Content read threshold reached, proceeding to finalBytes");
                     finalBytes();
                 } else {
                     // Needs to read more data, so send the data downstream,
                     // expecting that downstream will continue to request more data.
+                    System.out.println("[CipherSubscriber] Sending " + outputBuffer.length + " bytes to wrapped subscriber");
                     wrappedSubscriber.onNext(ByteBuffer.wrap(outputBuffer));
                 }
             }
         } else {
             // Do nothing
+            System.out.println("[CipherSubscriber] No data to process, forwarding buffer directly");
             wrappedSubscriber.onNext(byteBuffer);
         }
     }
@@ -110,48 +134,73 @@ private int getAmountToReadFromByteBuffer(ByteBuffer byteBuffer) {
         // If content length is null, we should include everything in the cipher because the stream is essentially
         // unbounded.
         if (contentLength == null) {
+            System.out.println("[CipherSubscriber] Content length is null, reading entire buffer: " + byteBuffer.remaining());
             return byteBuffer.remaining();
         }
 
         long amountReadSoFar = contentRead.getAndAdd(byteBuffer.remaining());
         long amountRemaining = Math.max(0, contentLength - amountReadSoFar);
+        System.out.println("[CipherSubscriber] Buffer read calculation - read: " + amountReadSoFar + ", remaining: " + amountRemaining + ", buffer size: " + byteBuffer.remaining());
 
         if (amountRemaining > byteBuffer.remaining()) {
+            System.out.println("[CipherSubscriber] Reading entire buffer: " + byteBuffer.remaining());
             return byteBuffer.remaining();
         } else {
+            System.out.println("[CipherSubscriber] Reading partial buffer: " + amountRemaining);
             return Math.toIntExact(amountRemaining);
         }
     }
 
     @Override
     public void onError(Throwable t) {
+        System.out.println("[CipherSubscriber] Error occurred: " + t.getMessage());
         wrappedSubscriber.onError(t);
     }
 
     @Override
     public void onComplete() {
+        System.out.println("[CipherSubscriber] onComplete called");
         wrappedSubscriber.onComplete();
     }
 
     public void finalBytes() {
+        System.out.println("[CipherSubscriber] finalBytes called, isLastPart: " + isLastPart + ", onCompleteCalled: " + onCompleteCalled);
+        // onComplete can be signalled to CipherSubscriber multiple times,
+        // but additional calls should be deduped to avoid calling onNext multiple times
+        // and raising exceptions.
+        if (onCompleteCalled) {
+            System.out.println("[CipherSubscriber] finalBytes already called, returning");
+            return;
+        }
+        onCompleteCalled = true;
+
         // If this isn't the last part, skip doFinal and just send outputBuffer downstream.
         // doFinal requires that all parts have been processed to compute the tag,
         // so the tag will only be computed when the last part is processed.
         if (!isLastPart) {
+            System.out.println("[CipherSubscriber] Not last part, sending output buffer of size: " + (outputBuffer != null ? outputBuffer.length : 0));
+            // First, propagate the bytes that were in outputBuffer downstream.
             wrappedSubscriber.onNext(ByteBuffer.wrap(outputBuffer));
+            // Then, propagate the onComplete signal downstream.
+//            wrappedSubscriber.onComplete();
             return;
         }
 
         // If this is the last part, compute doFinal and include its result in the value sent downstream.
         // The result of doFinal MUST be included with the bytes that were in outputBuffer in the final onNext call.
-        byte[] finalBytes;
+        byte[] finalBytes = null;
         try {
+            System.out.println("[CipherSubscriber] Calling cipher.doFinal()");
             finalBytes = cipher.doFinal();
+            System.out.println("[CipherSubscriber] doFinal produced " + (finalBytes != null ? finalBytes.length : 0) + " bytes");
         } catch (final GeneralSecurityException exception) {
             // Even if doFinal fails, downstream still expects to receive the bytes that were in outputBuffer
+            System.out.println("[CipherSubscriber] Security exception during doFinal: " + exception.getMessage());
             wrappedSubscriber.onNext(ByteBuffer.wrap(outputBuffer));
             // Forward error, else the wrapped subscriber waits indefinitely
             wrappedSubscriber.onError(exception);
+            // Even though doFinal failed, propagate the onComplete signal downstream
+//            wrappedSubscriber.onComplete();
             throw new S3EncryptionClientSecurityException(exception.getMessage(), exception);
         }
 
@@ -160,18 +209,24 @@ public void finalBytes() {
         // This single onNext call must contain both the bytes from outputBuffer and the tag.
         byte[] combinedBytes;
         if (outputBuffer != null && outputBuffer.length > 0 && finalBytes != null && finalBytes.length > 0) {
+            System.out.println("[CipherSubscriber] Combining outputBuffer (" + outputBuffer.length + " bytes) with finalBytes (" + finalBytes.length + " bytes)");
             combinedBytes = new byte[outputBuffer.length + finalBytes.length];
             System.arraycopy(outputBuffer, 0, combinedBytes, 0, outputBuffer.length);
             System.arraycopy(finalBytes, 0, combinedBytes, outputBuffer.length, finalBytes.length);
         } else if (outputBuffer != null && outputBuffer.length > 0) {
+            System.out.println("[CipherSubscriber] Using only outputBuffer (" + outputBuffer.length + " bytes)");
             combinedBytes = outputBuffer;
         } else if (finalBytes != null && finalBytes.length > 0) {
+            System.out.println("[CipherSubscriber] Using only finalBytes (" + finalBytes.length + " bytes)");
             combinedBytes = finalBytes;
         } else {
+            System.out.println("[CipherSubscriber] No bytes to send");
             combinedBytes = new byte[0];
         }
 
+        System.out.println("[CipherSubscriber] Sending combined bytes to wrapped subscriber of length " + combinedBytes.length);
         wrappedSubscriber.onNext(ByteBuffer.wrap(combinedBytes));
+//        wrappedSubscriber.onComplete();
     }
 
 }