[sql] Recover Favicons v5 databases, with more recovery automation.

An entirely automated recovery system runs afoul of questions about
whether the corrupt database's schema can be trusted.
sql::Recovery::AutoRecoverTable() uses a schema created by the caller
to construct the recovery virtual table and then copies the data over.

sql::Recovery::SetupMeta() and GetMetaVersionNumber() simplify
accessing meta-table info in the corrupt database.

sql::test::IntegrityCheck() and CorruptSizeInHeader() helpers to
simplify common testing operations.

Rewrite ThumbnailDatabase v6 and v7 recovery code and tests using
these changes, and add a v5 recovery path.  Additionally handle
deprecated versions.

BUG=240396,109482

Review URL: https://codereview.chromium.org/50493012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235492 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 3 insertions, 20 deletions

diff --git a/sql/connection_unittest.cc b/sql/connection_unittest.cc
index 445db34..5ffc26a 100644
--- a/sql/connection_unittest.cc
+++ b/sql/connection_unittest.cc
@@ -11,6 +11,7 @@
 #include "sql/statement.h"
 #include "sql/test/error_callback_support.h"
 #include "sql/test/scoped_error_ignorer.h"
+#include "sql/test/test_helpers.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/sqlite/sqlite3.h"
 
@@ -502,32 +503,14 @@ TEST_F(SQLConnectionTest, RazeNOTADB2) {
 // essential for cases where the Open() can fail entirely, so the
 // Raze() cannot happen later.  Additionally test that when the
 // callback does this during Open(), the open is retried and succeeds.
-//
-// Most corruptions seen in the wild seem to happen when two pages in
-// the database were not written transactionally (the transaction
-// changed both, but one wasn't successfully written for some reason).
-// A special case of that is when the header indicates that the
-// database contains more pages than are in the file.  This breaks
-// things at a very basic level, verify that Raze() can handle it.
 TEST_F(SQLConnectionTest, RazeCallbackReopen) {
   const char* kCreateSql = "CREATE TABLE foo (id INTEGER PRIMARY KEY, value)";
   ASSERT_TRUE(db().Execute(kCreateSql));
   ASSERT_EQ(1, SqliteMasterCount(&db()));
-  int page_size = 0;
-  {
-    sql::Statement s(db().GetUniqueStatement("PRAGMA page_size"));
-    ASSERT_TRUE(s.Step());
-    page_size = s.ColumnInt(0);
-  }
   db().Close();
 
-  // Trim a single page from the end of the file.
-  {
-    file_util::ScopedFILE file(file_util::OpenFile(db_path(), "rb+"));
-    ASSERT_TRUE(file.get() != NULL);
-    ASSERT_EQ(0, fseek(file.get(), -page_size, SEEK_END));
-    ASSERT_TRUE(file_util::TruncateFile(file.get()));
-  }
+  // Corrupt the database so that nothing works, including PRAGMAs.
+  ASSERT_TRUE(sql::test::CorruptSizeInHeader(db_path()));
 
   // Open() will succeed, even though the PRAGMA calls within will
   // fail with SQLITE_CORRUPT, as will this PRAGMA.