Changeset 61023 in webkit

Timestamp:

Jun 11, 2010 9:17:05 AM (14 years ago)

Author:

eric@webkit.org

Message:

2010-06-11 Hans Wennborg <​hans@chromium.org>

Reviewed by Jeremy Orlow.

DOM storage should only create databases when needed
​https://bugs.webkit.org/show_bug.cgi?id=40301

As soon as a page attempts to use localstorage, StorageAreaSync will
create an empty database if one doesn't already exist. This can lead to
lots of unnecessary database files. In particular, they are created
even when the privacy settings or private browsing mode disallow
localstorage data, which may seem odd to the user.

Database creation should be put off in StorageAreaSync until it is time
to actually write something to the database.

Tests:

manual-tests/localstorage-empty-database.html

• manual-tests/localstorage-empty-database.html: Added.
• storage/StorageAreaSync.cpp: (WebCore::StorageAreaSync::StorageAreaSync): (WebCore::StorageAreaSync::openDatabase): (WebCore::StorageAreaSync::performImport): (WebCore::StorageAreaSync::sync):
• storage/StorageAreaSync.h: (WebCore::StorageAreaSync::):

Location:

trunk/WebCore

Files:

• ChangeLog (modified) (1 diff)
• manual-tests/localstorage-empty-database.html (added)
• storage/StorageAreaSync.cpp (modified) (6 diffs)
• storage/StorageAreaSync.h (modified) (2 diffs)

trunk/WebCore/ChangeLog

@@ +1 @@
+2010-06-11  Hans Wennborg  <hans@chromium.org>
+
+        Reviewed by Jeremy Orlow.
+
+        DOM storage should only create databases when needed
+        https://bugs.webkit.org/show_bug.cgi?id=40301
+
+        As soon as a page attempts to use localstorage, StorageAreaSync will
+        create an empty database if one doesn't already exist. This can lead to
+        lots of unnecessary database files. In particular, they are created
+        even when the privacy settings or private browsing mode disallow
+        localstorage data, which may seem odd to the user.
+
+        Database creation should be put off in StorageAreaSync until it is time
+        to actually write something to the database.
+
+        Tests:
+         manual-tests/localstorage-empty-database.html
+
+        * manual-tests/localstorage-empty-database.html: Added.
+        * storage/StorageAreaSync.cpp:
+        (WebCore::StorageAreaSync::StorageAreaSync):
+        (WebCore::StorageAreaSync::openDatabase):
+        (WebCore::StorageAreaSync::performImport):
+        (WebCore::StorageAreaSync::sync):
+        * storage/StorageAreaSync.h:
+        (WebCore::StorageAreaSync::):
+
 2010-06-11  Ilya Tikhonovsky  <loislo@chromium.org>
 

trunk/WebCore/storage/StorageAreaSync.cpp

@@ -30 +30 @@
 
 #include "EventNames.h"
+#include "FileSystem.h"
 #include "HTMLElement.h"
 #include "SecurityOrigin.h"
@@ -63 +64 @@
     , m_syncScheduled(false)
     , m_syncInProgress(false)
+    , m_databaseOpenFailed(false)
     , m_importComplete(false)
 {
@@ -199 +201 @@
 }
 
-void StorageAreaSync::performImport()
+void StorageAreaSync::openDatabase(OpenDatabaseParamType openingStrategy)
 {
     ASSERT(!isMainThread());
     ASSERT(!m_database.isOpen());
+    ASSERT(!m_databaseOpenFailed);
 
     String databaseFilename = m_syncManager->fullDatabaseFilename(m_databaseIdentifier);
+
+    if (!fileExists(databaseFilename) && openingStrategy == SkipIfNonExistent)
+        return;
 
     if (databaseFilename.isEmpty()) {
         LOG_ERROR("Filename for local storage database is empty - cannot open for persistent storage");
         markImported();
+        m_databaseOpenFailed = true;
         return;
     }
@@ -215 +222 @@
         LOG_ERROR("Failed to open database file %s for local storage", databaseFilename.utf8().data());
         markImported();
+        m_databaseOpenFailed = true;
         return;
     }
@@ -220 +228 @@
     if (!m_database.executeCommand("CREATE TABLE IF NOT EXISTS ItemTable (key TEXT UNIQUE ON CONFLICT REPLACE, value TEXT NOT NULL ON CONFLICT FAIL)")) {
         LOG_ERROR("Failed to create table ItemTable for local storage");
+        markImported();
+        m_databaseOpenFailed = true;
+        return;
+    }
+}
+
+void StorageAreaSync::performImport()
+{
+    ASSERT(!isMainThread());
+    ASSERT(!m_database.isOpen());
+
+    openDatabase(SkipIfNonExistent);
+    if (!m_database.isOpen()) {
         markImported();
         return;
@@ -286 +307 @@
     ASSERT(!isMainThread());
 
+    if (m_databaseOpenFailed)
+        return;
+    if (!m_database.isOpen())
+        openDatabase(CreateIfNonExistent);
     if (!m_database.isOpen())
         return;

trunk/WebCore/storage/StorageAreaSync.h

@@ -76 +76 @@
 
     private:
+        enum OpenDatabaseParamType {
+          CreateIfNonExistent,
+          SkipIfNonExistent
+        };
+
         void syncTimerFired(Timer<StorageAreaSync>*);
+        void openDatabase(OpenDatabaseParamType openingStrategy);
         void sync(bool clearItems, const HashMap<String, String>& items);
 
@@ -86 +92 @@
         bool m_syncScheduled;
         bool m_syncInProgress;
+        bool m_databaseOpenFailed;
 
         mutable Mutex m_importLock;