From 7e477bfe11f8bb31622353b64e85721df3cf9702 Mon Sep 17 00:00:00 2001
From: Mathias Agopian <mathias@google.com>
Date: Fri, 18 May 2012 16:50:58 -0700
Subject: [PATCH] make sure BufferQueue releases newly acquired buffers on
 failures

this prevents SurfaceTexture producer to hang in dequeueBuffer()
when something goes wrong in the consumer.
only the consumer gets an error and the current frame is kept
instead of the new one. the producer is unaware of the problem.

Bug: 6476587
Change-Id: Ie6db5526632aabc3e60229b93dfe29c19491ade4
---
 libs/gui/SurfaceTexture.cpp | 58 ++++++++++++++++++++-----------------
 1 file changed, 31 insertions(+), 27 deletions(-)

diff --git a/libs/gui/SurfaceTexture.cpp b/libs/gui/SurfaceTexture.cpp
index feaf07aae..30c0d9bfb 100644
--- a/libs/gui/SurfaceTexture.cpp
+++ b/libs/gui/SurfaceTexture.cpp
@@ -235,36 +235,39 @@ status_t SurfaceTexture::updateTexImage() {
         if (image == EGL_NO_IMAGE_KHR) {
             if (mEGLSlots[buf].mGraphicBuffer == NULL) {
                 ST_LOGE("updateTexImage: buffer at slot %d is null", buf);
-                return BAD_VALUE;
-            }
-            image = createImage(dpy, mEGLSlots[buf].mGraphicBuffer);
-            mEGLSlots[buf].mEglImage = image;
-            if (image == EGL_NO_IMAGE_KHR) {
-                // NOTE: if dpy was invalid, createImage() is guaranteed to
-                // fail. so we'd end up here.
-                return UNKNOWN_ERROR;
+                err = BAD_VALUE;
+            } else {
+                image = createImage(dpy, mEGLSlots[buf].mGraphicBuffer);
+                mEGLSlots[buf].mEglImage = image;
+                if (image == EGL_NO_IMAGE_KHR) {
+                    // NOTE: if dpy was invalid, createImage() is guaranteed to
+                    // fail. so we'd end up here.
+                    err = UNKNOWN_ERROR;
+                }
             }
         }
 
-        GLint error;
-        while ((error = glGetError()) != GL_NO_ERROR) {
-            ST_LOGW("updateTexImage: clearing GL error: %#04x", error);
+        if (err == NO_ERROR) {
+            GLint error;
+            while ((error = glGetError()) != GL_NO_ERROR) {
+                ST_LOGW("updateTexImage: clearing GL error: %#04x", error);
+            }
+
+            glBindTexture(mTexTarget, mTexName);
+            glEGLImageTargetTexture2DOES(mTexTarget, (GLeglImageOES)image);
+
+            while ((error = glGetError()) != GL_NO_ERROR) {
+                ST_LOGE("updateTexImage: error binding external texture image %p "
+                        "(slot %d): %#04x", image, buf, error);
+                err = UNKNOWN_ERROR;
+            }
+
+            if (err == NO_ERROR) {
+                err = syncForReleaseLocked(dpy);
+            }
         }
 
-        glBindTexture(mTexTarget, mTexName);
-        glEGLImageTargetTexture2DOES(mTexTarget, (GLeglImageOES)image);
-
-        while ((error = glGetError()) != GL_NO_ERROR) {
-            ST_LOGE("updateTexImage: error binding external texture image %p "
-                    "(slot %d): %#04x", image, buf, error);
-            err = UNKNOWN_ERROR;
-        }
-
-        if (err == OK) {
-            err = syncForReleaseLocked(dpy);
-        }
-
-        if (err != OK) {
+        if (err != NO_ERROR) {
             // Release the buffer we just acquired.  It's not safe to
             // release the old buffer, so instead we just drop the new frame.
             mBufferQueue->releaseBuffer(buf, dpy, mEGLSlots[buf].mFence);
@@ -279,12 +282,13 @@ status_t SurfaceTexture::updateTexImage() {
 
         // release old buffer
         if (mCurrentTexture != BufferQueue::INVALID_BUFFER_SLOT) {
-            status_t status = mBufferQueue->releaseBuffer(mCurrentTexture, dpy, mEGLSlots[mCurrentTexture].mFence);
+            status_t status = mBufferQueue->releaseBuffer(mCurrentTexture, dpy,
+                    mEGLSlots[mCurrentTexture].mFence);
 
             mEGLSlots[mCurrentTexture].mFence = EGL_NO_SYNC_KHR;
             if (status == BufferQueue::STALE_BUFFER_SLOT) {
                 freeBufferLocked(mCurrentTexture);
-            } else if (status != OK) {
+            } else if (status != NO_ERROR) {
                 ST_LOGE("updateTexImage: released invalid buffer");
                 err = status;
             }