From 8e93a5852c25eda9e75b8f6a14bbebe3bf9603a4 Mon Sep 17 00:00:00 2001
From: Masayuki Nakano <masayuki@d-toybox.com>
Date: Sun, 29 May 2011 08:39:27 +0900
Subject: [PATCH] Bug 659913 part.2 Implement AddObservers and RemoveObservers
 r=roc

---
 modules/libpref/public/Preferences.h | 11 +++++++++
 modules/libpref/src/Preferences.cpp  | 36 ++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+)

diff --git a/modules/libpref/public/Preferences.h b/modules/libpref/public/Preferences.h
index 324636bc2836..baab0a8947ca 100644
--- a/modules/libpref/public/Preferences.h
+++ b/modules/libpref/public/Preferences.h
@@ -193,6 +193,17 @@ public:
   static nsresult AddWeakObserver(nsIObserver* aObserver, const char* aPref);
   static nsresult RemoveObserver(nsIObserver* aObserver, const char* aPref);
 
+  /**
+   * Adds/Removes two or more observers for the root pref branch.
+   * Pass to aPrefs an array of const char* whose last item is NULL.
+   */
+  static nsresult AddStrongObservers(nsIObserver* aObserver,
+                                     const char** aPrefs);
+  static nsresult AddWeakObservers(nsIObserver* aObserver,
+                                   const char** aPrefs);
+  static nsresult RemoveObservers(nsIObserver* aObserver,
+                                  const char** aPrefs);
+
 protected:
   nsresult NotifyServiceObservers(const char *aSubject);
   nsresult UseDefaultPrefFile();
diff --git a/modules/libpref/src/Preferences.cpp b/modules/libpref/src/Preferences.cpp
index dd8b5e630c1b..3aa68f692573 100644
--- a/modules/libpref/src/Preferences.cpp
+++ b/modules/libpref/src/Preferences.cpp
@@ -1197,4 +1197,40 @@ Preferences::RemoveObserver(nsIObserver* aObserver,
   return sPreferences->mRootBranch->RemoveObserver(aPref, aObserver);
 }
 
+// static
+nsresult
+Preferences::AddStrongObservers(nsIObserver* aObserver,
+                                const char** aPrefs)
+{
+  for (PRUint32 i = 0; aPrefs[i]; i++) {
+    nsresult rv = AddStrongObserver(aObserver, aPrefs[i]);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  return NS_OK;
+}
+
+// static
+nsresult
+Preferences::AddWeakObservers(nsIObserver* aObserver,
+                              const char** aPrefs)
+{
+  for (PRUint32 i = 0; aPrefs[i]; i++) {
+    nsresult rv = AddWeakObserver(aObserver, aPrefs[i]);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  return NS_OK;
+}
+
+// static
+nsresult
+Preferences::RemoveObservers(nsIObserver* aObserver,
+                             const char** aPrefs)
+{
+  for (PRUint32 i = 0; aPrefs[i]; i++) {
+    nsresult rv = RemoveObserver(aObserver, aPrefs[i]);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  return NS_OK;
+}
+
 } // namespace mozilla