Return slices of ByteBuffers from getDataY/U/V() in I420Buffers.
I420Buffer implementations (I420BufferImpl and WrappedNativeI420Buffer) rely on
the 'position' of the underlying ByteBuffers to indicate the start of Y, U, and
V channels. Returning slices prevents callers from altering the state of the
I420Buffer by changing the position.
ByteBuffers are especially prone to accidentally moving the position: relative
read operations (such as get()) increment the position by the size of data read.
BUG=webrtc:8303
Change-Id: I52edce8a3bf46a6c41980ff5110a9480f021f22f
Reviewed-on: https://webrtc-review.googlesource.com/4521
Commit-Queue: Bjorn Mellem <mellem@webrtc.org>
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20050}diff --git a/sdk/android/api/org/webrtc/VideoFrame.java b/sdk/android/api/org/webrtc/VideoFrame.java
index 6a92cc9..a131121 100644
--- a/sdk/android/api/org/webrtc/VideoFrame.java
+++ b/sdk/android/api/org/webrtc/VideoFrame.java
@@ -59,17 +59,20 @@
public interface I420Buffer extends Buffer {
/**
* Returns a direct ByteBuffer containing Y-plane data. The buffer size is at least getStrideY()
- * * getHeight() bytes.
+ * * getHeight() bytes. Callers may mutate the ByteBuffer (eg. through relative-read
+ * operations), so implementations must return a new ByteBuffer or slice for each call.
*/
ByteBuffer getDataY();
/**
* Returns a direct ByteBuffer containing U-plane data. The buffer size is at least getStrideU()
- * * ((getHeight() + 1) / 2) bytes.
+ * * ((getHeight() + 1) / 2) bytes. Callers may mutate the ByteBuffer (eg. through relative-read
+ * operations), so implementations must return a new ByteBuffer or slice for each call.
*/
ByteBuffer getDataU();
/**
* Returns a direct ByteBuffer containing V-plane data. The buffer size is at least getStrideV()
- * * ((getHeight() + 1) / 2) bytes.
+ * * ((getHeight() + 1) / 2) bytes. Callers may mutate the ByteBuffer (eg. through relative-read
+ * operations), so implementations must return a new ByteBuffer or slice for each call.
*/
ByteBuffer getDataV();
diff --git a/sdk/android/src/java/org/webrtc/I420BufferImpl.java b/sdk/android/src/java/org/webrtc/I420BufferImpl.java
index 2f545e9..48efc25 100644
--- a/sdk/android/src/java/org/webrtc/I420BufferImpl.java
+++ b/sdk/android/src/java/org/webrtc/I420BufferImpl.java
@@ -81,17 +81,20 @@
@Override
public ByteBuffer getDataY() {
- return dataY;
+ // Return a slice to prevent relative reads from changing the position.
+ return dataY.slice();
}
@Override
public ByteBuffer getDataU() {
- return dataU;
+ // Return a slice to prevent relative reads from changing the position.
+ return dataU.slice();
}
@Override
public ByteBuffer getDataV() {
- return dataV;
+ // Return a slice to prevent relative reads from changing the position.
+ return dataV.slice();
}
@Override
diff --git a/sdk/android/src/java/org/webrtc/WrappedNativeI420Buffer.java b/sdk/android/src/java/org/webrtc/WrappedNativeI420Buffer.java
index 85d02e6..ba7f386 100644
--- a/sdk/android/src/java/org/webrtc/WrappedNativeI420Buffer.java
+++ b/sdk/android/src/java/org/webrtc/WrappedNativeI420Buffer.java
@@ -53,17 +53,20 @@
@Override
public ByteBuffer getDataY() {
- return dataY;
+ // Return a slice to prevent relative reads from changing the position.
+ return dataY.slice();
}
@Override
public ByteBuffer getDataU() {
- return dataU;
+ // Return a slice to prevent relative reads from changing the position.
+ return dataU.slice();
}
@Override
public ByteBuffer getDataV() {
- return dataV;
+ // Return a slice to prevent relative reads from changing the position.
+ return dataV.slice();
}
@Override