From 305a4881877c680ea38a4d48534efccb14613fdb Mon Sep 17 00:00:00 2001
From: "L. David Baron" <dbaron@dbaron.org>
Date: Thu, 31 Dec 2009 10:56:33 -0500
Subject: [PATCH] Add method to nsStyleSet to call EnsureUniqueInner on all CSS
 sheets.  (Bug 536379)  r=bzbarsky

---
 layout/style/nsCSSStyleSheet.cpp | 12 ++++++++++
 layout/style/nsCSSStyleSheet.h   |  4 ++++
 layout/style/nsStyleSet.cpp      | 38 ++++++++++++++++++++++++++++++++
 layout/style/nsStyleSet.h        |  6 +++--
 4 files changed, 58 insertions(+), 2 deletions(-)

diff --git a/layout/style/nsCSSStyleSheet.cpp b/layout/style/nsCSSStyleSheet.cpp
index c9646e4c345d..b2529fbb5e8d 100644
--- a/layout/style/nsCSSStyleSheet.cpp
+++ b/layout/style/nsCSSStyleSheet.cpp
@@ -1488,6 +1488,18 @@ nsCSSStyleSheet::EnsureUniqueInner()
   return eUniqueInner_ClonedInner;
 }
 
+PRBool
+nsCSSStyleSheet::AppendAllChildSheets(nsTArray<nsCSSStyleSheet*>& aArray)
+{
+  for (nsCSSStyleSheet* child = mInner->mFirstChild; child;
+       child = child->mNext) {
+    if (!aArray.AppendElement(child)) {
+      return PR_FALSE;
+    }
+  }
+  return PR_TRUE;
+}
+
 NS_IMETHODIMP
 nsCSSStyleSheet::Clone(nsICSSStyleSheet* aCloneParent,
                        nsICSSImportRule* aCloneOwnerRule,
diff --git a/layout/style/nsCSSStyleSheet.h b/layout/style/nsCSSStyleSheet.h
index c6e67a99fb6b..c39b08a6a6a2 100644
--- a/layout/style/nsCSSStyleSheet.h
+++ b/layout/style/nsCSSStyleSheet.h
@@ -183,6 +183,10 @@ public:
   };
   EnsureUniqueInnerResult EnsureUniqueInner();
 
+  // Append all of this sheet's child sheets to aArray.  Return PR_TRUE
+  // on success and PR_FALSE on allocation failure.
+  PRBool AppendAllChildSheets(nsTArray<nsCSSStyleSheet*>& aArray);
+
   PRBool UseForPresentation(nsPresContext* aPresContext,
                             nsMediaQueryResultCacheKey& aKey) const;
 
diff --git a/layout/style/nsStyleSet.cpp b/layout/style/nsStyleSet.cpp
index cfeb85808095..f60cb1d1424d 100644
--- a/layout/style/nsStyleSet.cpp
+++ b/layout/style/nsStyleSet.cpp
@@ -1161,3 +1161,41 @@ nsStyleSet::MediumFeaturesChanged(nsPresContext* aPresContext)
 
   return stylesChanged;
 }
+
+nsCSSStyleSheet::EnsureUniqueInnerResult
+nsStyleSet::EnsureUniqueInnerOnCSSSheets()
+{
+  nsAutoTArray<nsCSSStyleSheet*, 32> queue;
+  for (PRUint32 i = 0; i < NS_ARRAY_LENGTH(gCSSSheetTypes); ++i) {
+    nsCOMArray<nsIStyleSheet> &sheets = mSheets[gCSSSheetTypes[i]];
+    for (PRUint32 j = 0, j_end = sheets.Count(); j < j_end; ++j) {
+      nsCSSStyleSheet *sheet = static_cast<nsCSSStyleSheet*>(sheets[j]);
+      if (!queue.AppendElement(sheet)) {
+        return nsCSSStyleSheet::eUniqueInner_CloneFailed;
+      }
+    }
+  }
+
+  nsCSSStyleSheet::EnsureUniqueInnerResult res =
+    nsCSSStyleSheet::eUniqueInner_AlreadyUnique;
+  while (!queue.IsEmpty()) {
+    PRUint32 idx = queue.Length() - 1;
+    nsCSSStyleSheet *sheet = queue[idx];
+    queue.RemoveElementAt(idx);
+
+    nsCSSStyleSheet::EnsureUniqueInnerResult sheetRes =
+      sheet->EnsureUniqueInner();
+    if (sheetRes == nsCSSStyleSheet::eUniqueInner_CloneFailed) {
+      return sheetRes;
+    }
+    if (sheetRes == nsCSSStyleSheet::eUniqueInner_ClonedInner) {
+      res = sheetRes;
+    }
+
+    // Enqueue all the sheet's children.
+    if (!sheet->AppendAllChildSheets(queue)) {
+      return nsCSSStyleSheet::eUniqueInner_CloneFailed;
+    }
+  }
+  return res;
+}
diff --git a/layout/style/nsStyleSet.h b/layout/style/nsStyleSet.h
index 30d1d4c44bc2..c57e28c1f54e 100644
--- a/layout/style/nsStyleSet.h
+++ b/layout/style/nsStyleSet.h
@@ -48,7 +48,7 @@
 #define nsStyleSet_h_
 
 #include "nsIStyleRuleProcessor.h"
-#include "nsICSSStyleSheet.h"
+#include "nsCSSStyleSheet.h"
 #include "nsBindingManager.h"
 #include "nsRuleNode.h"
 #include "nsTArray.h"
@@ -277,7 +277,9 @@ class nsStyleSet
   void RuleNodeInUse() {
     --mUnusedRuleNodeCount;
   }
-  
+
+  nsCSSStyleSheet::EnsureUniqueInnerResult EnsureUniqueInnerOnCSSSheets();
+
  private:
   // Not to be implemented
   nsStyleSet(const nsStyleSet& aCopy);