Add Bitmap#getHardwareBuffer

Bug: 148155907
Bug: 135299581
Test: TODO

Hidden for now. We'd like to make it an SDK API eventually
(b/148155907).

Internal code is currently calling createGraphicBufferHandle. This is
not something we plan to expose from the UI rendering module, so add a
method to get a HardwareBuffer instead. This is something we were
already planning to add. It seems that clients of
createGraphicBufferHandle really wanted a Parcelable to pass the
HARDWARE Bitmap to another thread. This should satisfy that use case.

Change-Id: Id701f7c7eab37830cd7d2cdb929cbe6ba4eca119
diff --git a/core/jni/android/graphics/Bitmap.cpp b/core/jni/android/graphics/Bitmap.cpp
index ec6e71d..130322a 100755
--- a/core/jni/android/graphics/Bitmap.cpp
+++ b/core/jni/android/graphics/Bitmap.cpp
@@ -19,10 +19,10 @@
 #include <utils/Color.h>
 
 #ifdef __ANDROID__ // Layoutlib does not support graphic buffer, parcel or render thread
-#include <binder/Parcel.h>
-#include <renderthread/RenderProxy.h>
 #include <android_runtime/android_graphics_GraphicBuffer.h>
+#include <binder/Parcel.h>
 #include <dlfcn.h>
+#include <renderthread/RenderProxy.h>
 #endif
 
 #include "core_jni_helpers.h"
@@ -1029,6 +1029,9 @@
 #ifdef __ANDROID__ // Layoutlib does not support graphic buffer
 typedef AHardwareBuffer* (*AHB_from_HB)(JNIEnv*, jobject);
 AHB_from_HB AHardwareBuffer_fromHardwareBuffer;
+
+typedef jobject (*AHB_to_HB)(JNIEnv*, AHardwareBuffer*);
+AHB_to_HB AHardwareBuffer_toHardwareBuffer;
 #endif
 
 static jobject Bitmap_wrapHardwareBufferBitmap(JNIEnv* env, jobject, jobject hardwareBuffer,
@@ -1060,6 +1063,19 @@
 #endif
 }
 
+static jobject Bitmap_getHardwareBuffer(JNIEnv* env, jobject, jlong bitmapPtr) {
+#ifdef __ANDROID__ // Layoutlib does not support graphic buffer
+    LocalScopedBitmap bitmapHandle(bitmapPtr);
+    LOG_ALWAYS_FATAL_IF(!bitmapHandle->isHardware(),
+            "Hardware config is only supported config in Bitmap_getHardwareBuffer");
+
+    Bitmap& bitmap = bitmapHandle->bitmap();
+    return AHardwareBuffer_toHardwareBuffer(env, bitmap.hardwareBuffer());
+#else
+    return NULL;
+#endif
+}
+
 static jboolean Bitmap_isImmutable(CRITICAL_JNI_PARAMS_COMMA jlong bitmapHandle) {
     LocalScopedBitmap bitmapHolder(bitmapHandle);
     if (!bitmapHolder.valid()) return JNI_FALSE;
@@ -1126,6 +1142,8 @@
         (void*) Bitmap_wrapHardwareBufferBitmap },
     {   "nativeCreateGraphicBufferHandle", "(J)Landroid/graphics/GraphicBuffer;",
         (void*) Bitmap_createGraphicBufferHandle },
+    {   "nativeGetHardwareBuffer", "(J)Landroid/hardware/HardwareBuffer;",
+        (void*) Bitmap_getHardwareBuffer },
     {   "nativeComputeColorSpace",  "(J)Landroid/graphics/ColorSpace;", (void*)Bitmap_computeColorSpace },
     {   "nativeSetColorSpace",      "(JJ)V", (void*)Bitmap_setColorSpace },
     {   "nativeIsSRGB",             "(J)Z", (void*)Bitmap_isSRGB },
@@ -1150,6 +1168,10 @@
             (AHB_from_HB)dlsym(handle_, "AHardwareBuffer_fromHardwareBuffer");
     LOG_ALWAYS_FATAL_IF(AHardwareBuffer_fromHardwareBuffer == nullptr,
                         "Failed to find required symbol AHardwareBuffer_fromHardwareBuffer!");
+
+    AHardwareBuffer_toHardwareBuffer = (AHB_to_HB)dlsym(handle_, "AHardwareBuffer_toHardwareBuffer");
+    LOG_ALWAYS_FATAL_IF(AHardwareBuffer_toHardwareBuffer == nullptr,
+                        " Failed to find required symbol AHardwareBuffer_toHardwareBuffer!");
 #endif
     return android::RegisterMethodsOrDie(env, "android/graphics/Bitmap", gBitmapMethods,
                                          NELEM(gBitmapMethods));
diff --git a/graphics/java/android/graphics/Bitmap.java b/graphics/java/android/graphics/Bitmap.java
index 9c2e95f..c1e7a36 100644
--- a/graphics/java/android/graphics/Bitmap.java
+++ b/graphics/java/android/graphics/Bitmap.java
@@ -2243,6 +2243,19 @@
         return nativeCreateGraphicBufferHandle(mNativePtr);
     }
 
+    /**
+     * @return {@link HardwareBuffer} which is internally used by hardware bitmap
+     *
+     * Note: the HardwareBuffer does *not* have an associated {@link ColorSpace}.
+     * To render this object the same as its rendered with this Bitmap, you
+     * should also call {@link getColorSpace}.
+     *
+     * @hide
+     */
+    public HardwareBuffer getHardwareBuffer() {
+        return nativeGetHardwareBuffer(mNativePtr);
+    }
+
     //////////// native methods
 
     private static native Bitmap nativeCreate(int[] colors, int offset,
@@ -2308,6 +2321,7 @@
     private static native Bitmap nativeWrapHardwareBufferBitmap(HardwareBuffer buffer,
                                                                 long nativeColorSpace);
     private static native GraphicBuffer nativeCreateGraphicBufferHandle(long nativeBitmap);
+    private static native HardwareBuffer nativeGetHardwareBuffer(long nativeBitmap);
     private static native ColorSpace nativeComputeColorSpace(long nativePtr);
     private static native void nativeSetColorSpace(long nativePtr, long nativeColorSpace);
     private static native boolean nativeIsSRGB(long nativePtr);