Check for pixels allocation failure

Standard memory allocator in Skia abort when an allocation request
fails. However, when allocating in managed heap, need to check for
allocation failure in allocPixels(). This add checks for all allocPixels
calls in Skia Bitmap code.

Bug: 3418381
Change-Id: I3c4ac403a3c073d64a689b29d3baccdc7fc90e1a

2 files changed, 29 insertions, 4 deletions

diff --git a/include/core/SkBitmap.h b/include/core/SkBitmap.h
index 1def198..84d069c 100644
--- a/include/core/SkBitmap.h
+++ b/include/core/SkBitmap.h
@@ -404,6 +404,19 @@ public:
         this->extractAlpha(dst, paint, NULL, offset);
     }
 
+    /** Set dst to contain alpha layer of this bitmap. If destination bitmap
+        fails to be initialized, e.g. because allocator can't allocate pixels
+        for it, dst will be resetted (zero width and height, no pixels).
+
+        @param dst The bitmap to be filled with alpha layer
+        @param paint The paint to draw with
+        @param allocator Allocator used to allocate the pixelref for the dst
+                         bitmap. If this is null, the standard HeapAllocator
+                         will be used.
+        @param offset If not null, it is set to top-left coordinate to position
+                      the returned bitmap so that it visually lines up with the
+                      original
+    */
     void extractAlpha(SkBitmap* dst, const SkPaint* paint, Allocator* allocator,
                       SkIPoint* offset) const;
 
diff --git a/src/core/SkBitmap.cpp b/src/core/SkBitmap.cpp
index e7d9537..0dc4ddc 100644
--- a/src/core/SkBitmap.cpp
+++ b/src/core/SkBitmap.cpp
@@ -1138,8 +1138,19 @@ void SkBitmap::extractAlpha(SkBitmap* dst, const SkPaint* paint,
     NO_FILTER_CASE:
         dst->setConfig(SkBitmap::kA8_Config, this->width(), this->height(),
                        srcM.fRowBytes);
-        dst->allocPixels(allocator, NULL);
-        GetBitmapAlpha(*this, dst->getAddr8(0, 0), srcM.fRowBytes);
+        if (dst->allocPixels(allocator, NULL)) {
+            GetBitmapAlpha(*this, dst->getAddr8(0, 0), srcM.fRowBytes);
+            if (offset) {
+                offset->set(0, 0);
+            }
+            return;
+        }
+    ALLOC_ERR:
+        // Allocation of pixels for alpha bitmap failed.
+        SkDebugf("extractAlpha failed to allocate (%d,%d) alpha bitmap\n",
+                 dst->width(), dst->height());
+        // When pixels can't be allocated, reset destination bitmap
+        dst->reset();
         if (offset) {
             offset->set(0, 0);
         }
@@ -1157,7 +1168,9 @@ void SkBitmap::extractAlpha(SkBitmap* dst, const SkPaint* paint,
 
     dst->setConfig(SkBitmap::kA8_Config, dstM.fBounds.width(),
                    dstM.fBounds.height(), dstM.fRowBytes);
-    dst->allocPixels(allocator, NULL);
+    if (!dst->allocPixels(allocator, NULL)) {
+        goto ALLOC_ERR;
+    }
     memcpy(dst->getPixels(), dstM.fImage, dstM.computeImageSize());
     if (offset) {
         offset->set(dstM.fBounds.fLeft, dstM.fBounds.fTop);
@@ -1341,4 +1354,3 @@ void SkBitmap::validate() const {
 #endif
 }
 #endif
-