Recreate the WebData database on a catastrophic SQL error

sql/connection.cc

 // 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.
 
 #include "sql/connection.h"
 
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <string.h>
@@ skipping 1715 matching lines @@
 
   // http://www.sqlite.org/pragma.html#pragma_journal_mode
   // DELETE (default) - delete -journal file to commit.
   // TRUNCATE - truncate -journal file to commit.
   // PERSIST - zero out header of -journal file to commit.
   // TRUNCATE should be faster than DELETE because it won't need directory
   // changes for each transaction.  PERSIST may break the spirit of using
   // secure_delete.
   ignore_result(Execute("PRAGMA journal_mode = TRUNCATE"));
 
+  bool was_poisoned = poisoned_;
+  if (was_poisoned) {
+    Close();
+    if (retry_flag == RETRY_ON_POISON)
+      return OpenInternal(file_name, NO_RETRY);
+    return false;
+  }

[Scott Hess - ex-Googler, 2016/08/12 21:11:53]

I'm going to post you an alternative, once I've finished the test for it.  I'm a
little concerned about this blanket check.  It's plausible, but it feels like it
should be at the end of the method, or it should be outside the scope of the
method, so that it covers all the cases where someone poisoned the database
during the open/setup process.  

+
   const base::TimeDelta kBusyTimeout =
     base::TimeDelta::FromSeconds(kBusyTimeoutSeconds);
 
   if (page_size_ != 0) {
     // Enforce SQLite restrictions on |page_size_|.
     DCHECK(!(page_size_ & (page_size_ - 1)))
         << " page_size_ " << page_size_ << " is not a power of two.";
     const int kSqliteMaxPageSize = 32768;  // from sqliteLimit.h
     DCHECK_LE(page_size_, kSqliteMaxPageSize);
     const std::string sql =
@@ skipping 228 matching lines @@
   ignore_result(Execute(kNoWritableSchema));
 
   return ret;
 }
 
 base::TimeTicks TimeSource::Now() {
   return base::TimeTicks::Now();
 }
 
 }  // namespace sql