Method checkAllPageChecksums

fdbserver/KeyValueStoreSQLite.actor.cpp:1310–1407

Returns number of pages which failed checksum.

// Returns number of pages which failed checksum.
int SQLiteDB::checkAllPageChecksums() {
	ASSERT(!haveMutex);
	ASSERT(page_checksums); // This should never be called on SQLite databases that do not have page checksums.

	double startT = timer();

	// First try to open an existing file
	std::string apath = abspath(filename);
	std::string walpath = apath + "-wal";

	/* REMOVE THIS BEFORE CHECKIN */ if (!fileExists(apath))
		return 0;

	TraceEvent("SQLitePageChecksumScanBegin").detail("File", apath);

	ErrorOr<Reference<IAsyncFile>> dbFile = waitForAndGet(
	    errorOr(IAsyncFileSystem::filesystem()->open(apath, IAsyncFile::OPEN_READONLY | IAsyncFile::OPEN_LOCK, 0)));
	ErrorOr<Reference<IAsyncFile>> walFile = waitForAndGet(
	    errorOr(IAsyncFileSystem::filesystem()->open(walpath, IAsyncFile::OPEN_READONLY | IAsyncFile::OPEN_LOCK, 0)));

	if (dbFile.isError())
		throw dbFile.getError(); // If we've failed to open the file, throw an exception
	if (walFile.isError())
		throw walFile.getError(); // If we've failed to open the file, throw an exception

	// Now that the file itself is open and locked, let sqlite open the database
	// Note that VFSAsync will also call g_network->open (including for the WAL), so its flags are important, too
	// TODO:  If better performance is needed, make AsyncFileReadAheadCache work and be enabled by SQLITE_OPEN_READAHEAD
	// which was added for that purpose.
	int result = sqlite3_open_v2(apath.c_str(), &db, SQLITE_OPEN_READONLY, nullptr);
	checkError("open", result);

	// This check has the useful side effect of actually opening/reading the database.  If we were not doing this,
	// then we could instead open a read cursor for the same effect, as currently tryReadEveryDbPage() requires it.
	Statement* jm = new Statement(*this, "PRAGMA journal_mode");
	ASSERT(jm->nextRow());
	if (jm->column(0) != LiteralStringRef("wal")) {
		TraceEvent(SevError, "JournalModeError").detail("Filename", filename).detail("Mode", jm->column(0));
		ASSERT(false);
	}
	delete jm;

	btree = db->aDb[0].pBt;
	initPagerCodec();
	sqlite3_extended_result_codes(db, 1);

	sqlite3_mutex_enter(db->mutex);
	haveMutex = true;

	pPagerCodec->silent = true;
	Pgno p = 1;
	int readErrors = 0;
	int corruptPages = 0;
	int totalErrors = 0;

	while (1) {
		int type;
		int zero;