libgui: Add generation numbers to BufferQueue
This change allows producers to set a generation number on a
BufferQueue. This number will be embedded in any new GraphicBuffers
created in that BufferQueue, and attempts to attach buffers which have
a different generation number will fail.
It also plumbs the setGenerationNumber method through Surface, with the
additional effect that any buffers attached to the Surface after
setting a new generation number will automatically be updated with the
new number (as opposed to failing, as would happen on through IGBP).
Bug: 20923096
Change-Id: I32bf726b035f99c3e5834beaf76afb9f01adcbc2
diff --git a/libs/gui/BufferQueueConsumer.cpp b/libs/gui/BufferQueueConsumer.cpp
index 4174676..ae796b1 100644
--- a/libs/gui/BufferQueueConsumer.cpp
+++ b/libs/gui/BufferQueueConsumer.cpp
@@ -248,6 +248,13 @@
return INVALID_OPERATION;
}
+ if (buffer->getGenerationNumber() != mCore->mGenerationNumber) {
+ BQ_LOGE("attachBuffer: generation number mismatch [buffer %u] "
+ "[queue %u]", buffer->getGenerationNumber(),
+ mCore->mGenerationNumber);
+ return BAD_VALUE;
+ }
+
// Find a free slot to put the buffer into
int found = BufferQueueCore::INVALID_BUFFER_SLOT;
if (!mCore->mFreeSlots.empty()) {