Use SkSet to fix issue when pdf generates an exp number of resources.
The problem fixed - http://code.google.com/p/skia/issues/detail?id=940 - is that getResources will recursively obtain all child resource recursively without checking for duplicates.
If we have lots of duplicates, then we try to build a very large vector (exponential with the number of nodes usually) and sooner or later we end up using too much memory and crash.
A possible solution could have been to make sure resources do not have duplicates, but that requirement is impractical, and it this leaves the solution fragile, if there is any issue in the tree, we crash.
When we emit the pdf, the large number of duplicates is not an issue, because SkPDFCatalog::addObject will deal with duplicates.
I have run the gm with --config pdf, and the images are 100% same bits, while the pdfs have the same size but some very small changes, the order of some objects.
Review URL: https://codereview.appspot.com/6744050
git-svn-id: http://skia.googlecode.com/svn/trunk@7883 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/pdf/SkPDFFormXObject.cpp b/src/pdf/SkPDFFormXObject.cpp
index 5e33995b..884e6db 100644
--- a/src/pdf/SkPDFFormXObject.cpp
+++ b/src/pdf/SkPDFFormXObject.cpp
@@ -20,16 +20,8 @@
// We don't want to keep around device because we'd have two copies
// of content, so reference or copy everything we need (content and
// resources).
- device->getResources(&fResources, false);
-
- // Fail fast if in the tree of resources a child references a parent.
- // If there is an issue, getResources will end up consuming all memory.
- // TODO: A better approach might be for all SkPDFObject to keep track
- // of possible cycles.
-#ifdef SK_DEBUG
- SkTDArray<SkPDFObject*> dummy_resourceList;
- getResources(&dummy_resourceList);
-#endif
+ SkTSet<SkPDFObject*> emptySet;
+ device->getResources(emptySet, &fResources, false);
SkAutoTUnref<SkStream> content(device->content());
setData(content.get());
@@ -64,6 +56,10 @@
fResources.unrefAll();
}
-void SkPDFFormXObject::getResources(SkTDArray<SkPDFObject*>* resourceList) {
- GetResourcesHelper(&fResources, resourceList);
+void SkPDFFormXObject::getResources(
+ const SkTSet<SkPDFObject*>& knownResourceObjects,
+ SkTSet<SkPDFObject*>* newResourceObjects) {
+ GetResourcesHelper(&fResources.toArray(),
+ knownResourceObjects,
+ newResourceObjects);
}