From 64d8d66e6f197c31f3b51eb8e073a383ffa7f289 Mon Sep 17 00:00:00 2001
From: "mats.palmgren%bredband.net"
 <mats.palmgren%bredband.net@18797224-902f-48f8-a5cc-f745e15eee43>
Date: Wed, 11 Nov 2009 03:50:20 +0000
Subject: [PATCH] Corrupt prefs.js file not removed if backup file
 (invalidprefs.js) exists. b=495735 r=benjamin a1.9.0.16=dveditz

git-svn-id: svn://10.0.0.236/trunk@258961 18797224-902f-48f8-a5cc-f745e15eee43
---
 mozilla/modules/libpref/src/nsPrefService.cpp | 37 +++++++++++--------
 mozilla/modules/libpref/src/nsPrefService.h   |  5 +--
 2 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/mozilla/modules/libpref/src/nsPrefService.cpp b/mozilla/modules/libpref/src/nsPrefService.cpp
index 27ad9cddf32..8e43f35b2f5 100644
--- a/mozilla/modules/libpref/src/nsPrefService.cpp
+++ b/mozilla/modules/libpref/src/nsPrefService.cpp
@@ -21,6 +21,7 @@
  *
  * Contributor(s):
  *   Alec Flett <alecf@netscape.com>
+ *   Mats Palmgren <matspal@gmail.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
  * either the GNU General Public License Version 2 or later (the "GPL"), or
@@ -85,10 +86,6 @@ static nsresult pref_InitInitialObjects(void);
  */
 
 nsPrefService::nsPrefService()
-: mDontWriteUserPrefs(PR_FALSE)
-#if MOZ_PROFILESHARING
-  , mDontWriteSharedUserPrefs(PR_FALSE)
-#endif
 {
 }
 
@@ -367,10 +364,22 @@ nsresult nsPrefService::UseUserPrefFile()
 nsresult nsPrefService::MakeBackupPrefFile(nsIFile *aFile)
 {
   // Example: this copies "prefs.js" to "Invalidprefs.js" in the same directory.
+  // "Invalidprefs.js" is removed if it exists, prior to making the copy.
   nsAutoString newFilename;
   nsresult rv = aFile->GetLeafName(newFilename);
   NS_ENSURE_SUCCESS(rv, rv);
   newFilename.Insert(NS_LITERAL_STRING("Invalid"), 0);
+  nsCOMPtr<nsIFile> newFile;
+  rv = aFile->GetParent(getter_AddRefs(newFile));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = newFile->Append(newFilename);
+  NS_ENSURE_SUCCESS(rv, rv);
+  PRBool exists = PR_FALSE;
+  newFile->Exists(&exists);
+  if (exists) {
+    rv = newFile->Remove(PR_FALSE);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
   rv = aFile->CopyTo(nsnull, newFilename);
   NS_ENSURE_SUCCESS(rv, rv);
   return rv;
@@ -395,7 +404,10 @@ nsresult nsPrefService::ReadAndOwnUserPrefFile(nsIFile *aFile)
   if (exists) {
     rv = openPrefFile(mCurrentFile);
     if (NS_FAILED(rv)) {
-      mDontWriteUserPrefs = NS_FAILED(MakeBackupPrefFile(mCurrentFile));
+      // Save a backup copy of the current (invalid) prefs file, since all prefs
+      // from the error line to the end of the file will be lost (bug 361102).
+      // TODO we should notify the user about it (bug 523725).
+      MakeBackupPrefFile(mCurrentFile);
     }
   } else {
     rv = NS_ERROR_FILE_NOT_FOUND;
@@ -424,7 +436,10 @@ nsresult nsPrefService::ReadAndOwnSharedUserPrefFile(nsIFile *aFile)
 
   nsresult rv = openPrefFile(mCurrentSharedFile);
   if (NS_FAILED(rv) && rv != NS_ERROR_FILE_NOT_FOUND) {
-    mDontWriteSharedUserPrefs = NS_FAILED(MakeBackupPrefFile(mCurrentSharedFile));
+    // Save a backup copy of the current (invalid) prefs file, since all prefs
+    // from the error line to the end of the file will be lost (bug 361102).
+    // TODO we should notify the user about it (bug 523725).
+    MakeBackupPrefFile(mCurrentSharedFile);
   }
 
 #ifdef MOZ_PROFILESHARING
@@ -494,16 +509,6 @@ nsresult nsPrefService::WritePrefFile(nsIFile* aFile)
   if (!gHashTable.ops)
     return NS_ERROR_NOT_INITIALIZED;
 
-  // Don't save user prefs if there was an error reading them and we failed
-  // to make a backup copy, since all prefs from the error line to the end of
-  // the file would be lost (bug 361102).
-  if (mDontWriteUserPrefs && aFile == mCurrentFile)
-    return NS_OK;
-#if MOZ_PROFILESHARING
-  if (mDontWriteSharedUserPrefs && aFile == mCurrentSharedFile)
-    return NS_OK;
-#endif
-
   // execute a "safe" save by saving through a tempfile
   rv = NS_NewSafeLocalFileOutputStream(getter_AddRefs(outStreamSink),
                                        aFile,
diff --git a/mozilla/modules/libpref/src/nsPrefService.h b/mozilla/modules/libpref/src/nsPrefService.h
index d6bc1fb61eb..aaa99f3b110 100644
--- a/mozilla/modules/libpref/src/nsPrefService.h
+++ b/mozilla/modules/libpref/src/nsPrefService.h
@@ -21,6 +21,7 @@
  *
  * Contributor(s):
  *   Brian Nesse <bnesse@netscape.com>
+ *   Mats Palmgren <matspal@gmail.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
  * either the GNU General Public License Version 2 or later (the "GPL"), or
@@ -79,11 +80,9 @@ protected:
 
 private:
   nsCOMPtr<nsIPrefBranch2> mRootBranch;
-  nsCOMPtr<nsIFile>       mCurrentFile;
-  PRPackedBool            mDontWriteUserPrefs;
+  nsCOMPtr<nsIFile>        mCurrentFile;
 #if MOZ_PROFILESHARING
   nsCOMPtr<nsIFile>       mCurrentSharedFile;
-  PRPackedBool            mDontWriteSharedUserPrefs;
 #endif
 };