AppCache: Run a quick integrity check on the sqlite database when opening.

sql/connection.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SQL_CONNECTION_H_
 #define SQL_CONNECTION_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 132 matching lines @@
   // for SQLite error codes and database version numbers.
   void set_histogram_tag(const std::string& tag) {
     histogram_tag_ = tag;
   }
 
   // Record a sparse UMA histogram sample under
   // |name|+"."+|histogram_tag_|.  If |histogram_tag_| is empty, no
   // histogram is recorded.
   void AddTaggedHistogram(const std::string& name, size_t sample) const;
 
-  // Run "PRAGMA integrity_check" and post each line of results into
-  // |messages|.  Returns the success of running the statement - per
-  // the SQLite documentation, if no errors are found the call should
-  // succeed, and a single value "ok" should be in messages.
-  bool IntegrityCheck(std::vector<std::string>* messages);
+  // Run "PRAGMA integrity_check" and post each line of
+  // results into |messages|.  Returns the success of running the
+  // statement - per the SQLite documentation, if no errors are found the
+  // call should succeed, and a single value "ok" should be in messages.
+  bool FullIntegrityCheck(std::vector<std::string>* messages);
+
+  // Runs "PRAGMA quick_check" and, unlike the FullIntegrityCheck method,
+  // interprets the results returning true if the the statement executes
+  // without error and results in a single "ok" value.
+  bool QuickIntegrityCheck() WARN_UNUSED_RESULT;
 
   // Initialization ------------------------------------------------------------
 
   // Initializes the SQL connection for the given file, returning true if the
   // file could be opened. You can call this or OpenInMemory.
   bool Open(const base::FilePath& path) WARN_UNUSED_RESULT;
 
   // Initializes the SQL connection for a temporary in-memory database. There
   // will be no associated file on disk, and the initial database will be
   // empty. You can call this or Open.
@@ skipping 365 matching lines @@
       WARN_UNUSED_RESULT;
 
   // Internal helper for const functions.  Like GetUniqueStatement(),
   // except the statement is not entered into open_statements_,
   // allowing this function to be const.  Open statements can block
   // closing the database, so only use in cases where the last ref is
   // released before close could be called (which should always be the
   // case for const functions).
   scoped_refptr<StatementRef> GetUntrackedStatement(const char* sql) const;
 
+  bool IntegrityCheckHelper(
+      const char* pragma_sql,
+      std::vector<std::string>* messages) WARN_UNUSED_RESULT;
+
   // The actual sqlite database. Will be NULL before Init has been called or if
   // Init resulted in an error.
   sqlite3* db_;
 
   // Parameters we'll configure in sqlite before doing anything else. Zero means
   // use the default value.
   int page_size_;
   int cache_size_;
   bool exclusive_locking_;
   bool restrict_to_user_;
@@ skipping 32 matching lines @@
 
   // Tag for auxiliary histograms.
   std::string histogram_tag_;
 
   DISALLOW_COPY_AND_ASSIGN(Connection);
 };
 
 }  // namespace sql
 
 #endif  // SQL_CONNECTION_H_