Canvas - CanvasRenderingContext2D.drawImage can throw 0x80040111 (NS_ERROR_NOT_AVAILABLE)

2 files changed, 20 insertions, 1 deletions

diff --git a/layout/base/nsLayoutUtils.cpp b/layout/base/nsLayoutUtils.cpp
index c8ff2670f..d4e758e86 100644
--- a/layout/base/nsLayoutUtils.cpp
+++ b/layout/base/nsLayoutUtils.cpp
@@ -6566,11 +6566,25 @@ nsLayoutUtils::SurfaceFromElement(nsIImageLoadingContent* aElement,
   nsCOMPtr<imgIRequest> imgRequest;
   rv = aElement->GetRequest(nsIImageLoadingContent::CURRENT_REQUEST,
                             getter_AddRefs(imgRequest));
-  if (NS_FAILED(rv) || !imgRequest)
+  if (NS_FAILED(rv)) {
     return result;
+  }
+
+  if (!imgRequest) {
+    // There's no image request. This is either because a request for
+    // a non-empty URI failed, or the URI is the empty string.
+    nsCOMPtr<nsIURI> currentURI;
+    aElement->GetCurrentURI(getter_AddRefs(currentURI));
+    if (!currentURI) {
+      // Treat the empty URI as available instead of broken state.
+      result.mHasSize = true;
+    }
+    return result;
+  }
 
   uint32_t status;
   imgRequest->GetImageStatus(&status);
+  result.mHasSize = status & imgIRequest::STATUS_SIZE_AVAILABLE;
   if ((status & imgIRequest::STATUS_LOAD_COMPLETE) == 0) {
     // Spec says to use GetComplete, but that only works on
     // nsIDOMHTMLImageElement, and we support all sorts of other stuff
@@ -6691,6 +6705,7 @@ nsLayoutUtils::SurfaceFromElement(HTMLCanvasElement* aElement,
   // in case this is being used by -moz-element()
   aElement->MarkContextClean();
 
+  result.mHasSize = true;
   result.mSize = size;
   result.mPrincipal = aElement->NodePrincipal();
   result.mIsWriteOnly = aElement->IsWriteOnly();
@@ -6737,6 +6752,7 @@ nsLayoutUtils::SurfaceFromElement(HTMLVideoElement* aElement,
   }
 
   result.mCORSUsed = aElement->GetCORSMode() != CORS_NONE;
+  result.mHasSize = true;
   result.mSize = ThebesIntSize(size);
   result.mPrincipal = principal.forget();
   result.mIsWriteOnly = false;
@@ -7775,6 +7791,7 @@ nsLayoutUtils::SurfaceFromElementResult::SurfaceFromElementResult()
   // Use safe default values here
   : mIsWriteOnly(true)
   , mIsStillLoading(false)
+  , mHasSize(false)
   , mCORSUsed(false)
   , mIsPremultiplied(true)
 {
diff --git a/layout/base/nsLayoutUtils.h b/layout/base/nsLayoutUtils.h
index c3221e8f2..68d7abd1a 100644
--- a/layout/base/nsLayoutUtils.h
+++ b/layout/base/nsLayoutUtils.h
@@ -2027,6 +2027,8 @@ public:
     /* Whether the element was still loading.  Some consumers need to handle
        this case specially. */
     bool mIsStillLoading;
+    /* Whether the element has a valid size. */
+    bool mHasSize;
     /* Whether the element used CORS when loading. */
     bool mCORSUsed;
     /* Whether the returned image contains premultiplied pixel data */