From f43e7520db24715459d2283fa51af80f0056094c Mon Sep 17 00:00:00 2001
From: Christian Hohnstaedt <christian@hohnstaedt.de>
Date: Fri, 22 Mar 2019 12:43:04 +0100
Subject: [PATCH] Support concurrent database access.

If a database is modified by another instance of XCA the passive
instance reloads and displays the changed parts.
---
 lib/base.h                  |  2 +-
 lib/db_base.cpp             | 24 +++++++++++++++++-
 lib/db_base.h               |  4 ++-
 lib/db_crl.cpp              |  1 +
 lib/db_x509.cpp             |  7 ++++--
 lib/db_x509.h               |  1 +
 lib/db_x509req.cpp          |  1 +
 lib/db_x509super.cpp        |  1 +
 lib/pki_base.cpp            |  2 +-
 lib/sql.cpp                 |  2 +-
 lib/sql.h                   |  1 +
 widgets/MW_database.cpp     | 50 +++++++++++++++++++++++++++++--------
 widgets/MainWindow.cpp      |  9 +++----
 widgets/MainWindow.h        |  4 ++-
 widgets/Options.cpp         |  1 -
 widgets/database_schema.cpp |  6 +++++
 16 files changed, 90 insertions(+), 26 deletions(-)

diff --git a/lib/base.h b/lib/base.h
index bdfcf6e4..ed6adb84 100644
--- a/lib/base.h
+++ b/lib/base.h
@@ -29,7 +29,7 @@
 #endif
 
 #define C_FILE ((strrchr(__FILE__, '/') ? : __FILE__- 1) + 1)
-#define TRACE qDebug("File: %s Func: %s Line: %d\n",C_FILE,__func__,__LINE__);
+#define TRACE qDebug("File: %s Func: %s Line: %d", C_FILE, __func__, __LINE__);
 
 #if (QT_VERSION >= QT_VERSION_CHECK(5, 0, 0))
 #define nativeSeparator(s) QDir::toNativeSeparators(s)
diff --git a/lib/db_base.cpp b/lib/db_base.cpp
index 13c44c53..96dd662f 100644
--- a/lib/db_base.cpp
+++ b/lib/db_base.cpp
@@ -141,6 +141,27 @@ void db_base::loadContainer()
 	emit columnsContentChanged();
 }
 
+void db_base::reloadContainer(const QList<enum pki_type> &typelist)
+{
+	bool match = false;
+	QList<enum pki_type> all_types = pkitype + pkitype_depends;
+	foreach(enum pki_type t, typelist) {
+		if (all_types.contains(t)) {
+			match = true;
+			break;
+		}
+	}
+	if (!match)
+		return;
+	qDebug() << "RELOAD" << class_name << all_types << typelist;
+	beginResetModel();
+	delete rootItem;
+	rootItem = newPKI();
+	endResetModel();
+
+	loadContainer();
+}
+
 void db_base::updateHeaders()
 {
 	QString s = allHeaders.toData();
@@ -288,6 +309,7 @@ void db_base::deletePKI(QModelIndex idx)
 			TransDone(e);
 			if (!e.isValid())
 				remFromCont(idx);
+			AffectedItems(pki->getSqlItemId());
 			mainwin->dbSqlError(e);
 		}
 	} catch (errorEx &err) {
@@ -336,7 +358,7 @@ void db_base::inToCont(pki_base *pki)
 pki_base *db_base::getByName(QString desc)
 {
 	QList<pki_base*> list = sqlSELECTpki<pki_base>(
-		QString("SELECT id FROM items WHERE name=? AND ") +
+		QString("SELECT id FROM items WHERE name=? AND del=0 AND ") +
 			sqlItemSelector(),
 		QList<QVariant>() << QVariant(desc));
 	return list.isEmpty() ? NULL : list[0];
diff --git a/lib/db_base.h b/lib/db_base.h
index ed80ae5a..8eedead9 100644
--- a/lib/db_base.h
+++ b/lib/db_base.h
@@ -44,6 +44,7 @@ class db_base: public QAbstractItemModel
 		void _removePKI(pki_base *pki );
 		void removeItem(QString k);
 		QList<enum pki_type> pkitype;
+		QList<enum pki_type> pkitype_depends;
 		MainWindow *mainwin;
 		QString class_name;
 		/* Sql table containing the 'hash' of this items */
@@ -60,7 +61,7 @@ class db_base: public QAbstractItemModel
 		bool isValidCol(int col) const;
 		static XSqlQuery sqlSELECTpki(QString query,
 				QList<QVariant> values = QList<QVariant>());
-		void timerEvent(QTimerEvent * event);
+		void timerEvent(QTimerEvent *event);
 		void restart_timer();
 
 	public:
@@ -110,6 +111,7 @@ class db_base: public QAbstractItemModel
 		pki_base *getByReference(pki_base *refpki);
 		pki_base *getByPtr(void *);
 		virtual void loadContainer();
+		void reloadContainer(const QList<enum pki_type> &typelist);
 		template <class T> QList<T *> getAll()
 		{
 			return sqlSELECTpki<T>(
diff --git a/lib/db_crl.cpp b/lib/db_crl.cpp
index 3629c174..d4518326 100644
--- a/lib/db_crl.cpp
+++ b/lib/db_crl.cpp
@@ -23,6 +23,7 @@ db_crl::db_crl(MainWindow *mw)
 	class_name = "crls";
 	sqlHashTable = "crls";
 	pkitype << revocation;
+	pkitype_depends << x509;
 	updateHeaders();
 	loadContainer();
 }
diff --git a/lib/db_x509.cpp b/lib/db_x509.cpp
index fc56ebaa..9fc7c094 100644
--- a/lib/db_x509.cpp
+++ b/lib/db_x509.cpp
@@ -31,13 +31,15 @@ db_x509::db_x509(MainWindow *mw)
 	class_name = "certificates";
 	sqlHashTable = "certs";
 	pkitype << x509;
+	pkitype_depends << x509_req;
 	updateHeaders();
 	loadContainer();
-	dereferenceIssuer();
 }
 
-void db_x509::dereferenceIssuer()
+void db_x509::loadContainer()
 {
+	db_x509super::loadContainer();
+
 	XSqlQuery q("SELECT item, issuer FROM certs WHERE issuer is NOT NULL");
 	while (q.next()) {
 		pki_base *root = rootItem;
@@ -56,6 +58,7 @@ void db_x509::dereferenceIssuer()
 			insertChild(root, cert);
 		}
 	}
+	emit columnsContentChanged();
 }
 
 dbheaderList db_x509::getHeaders()
diff --git a/lib/db_x509.h b/lib/db_x509.h
index 33c26778..ff0e065c 100644
--- a/lib/db_x509.h
+++ b/lib/db_x509.h
@@ -34,6 +34,7 @@ class db_x509: public db_x509super
 		db_x509(MainWindow *mw);
 		pki_base *newPKI(enum pki_type type = none);
 		pki_x509 *findIssuer(pki_x509 *client);
+		virtual void loadContainer();
 
 		bool updateView();
 		void updateViewAll();
diff --git a/lib/db_x509req.cpp b/lib/db_x509req.cpp
index 84e6a6e4..5a7e69e1 100644
--- a/lib/db_x509req.cpp
+++ b/lib/db_x509req.cpp
@@ -20,6 +20,7 @@ db_x509req::db_x509req(MainWindow *mw)
 	class_name = "requests";
 	sqlHashTable = "requests";
 	pkitype << x509_req;
+	pkitype_depends << x509;
 	updateHeaders();
 	loadContainer();
 }
diff --git a/lib/db_x509super.cpp b/lib/db_x509super.cpp
index 79d732dc..041ef23d 100644
--- a/lib/db_x509super.cpp
+++ b/lib/db_x509super.cpp
@@ -34,6 +34,7 @@ dbheaderList db_x509name::getHeaders()
 db_x509super::db_x509super(MainWindow *mw)
 	:db_x509name(mw)
 {
+	pkitype_depends << asym_key << smartCard;
 }
 
 void db_x509super::loadContainer()
diff --git a/lib/pki_base.cpp b/lib/pki_base.cpp
index b83bb72f..910ab924 100644
--- a/lib/pki_base.cpp
+++ b/lib/pki_base.cpp
@@ -195,7 +195,7 @@ QSqlError pki_base::deleteSql()
 	e = deleteSqlData();
 	if (e.isValid())
 		return e;
-	SQL_PREPARE(q, "DELETE FROM items WHERE id=?");
+	SQL_PREPARE(q, "UPDATE items SET del=1 WHERE id=?");
 	q.bindValue(0, sqlItemId);
 	q.exec();
 	return q.lastError();
diff --git a/lib/sql.cpp b/lib/sql.cpp
index 09fe5a78..182ed89b 100644
--- a/lib/sql.cpp
+++ b/lib/sql.cpp
@@ -17,7 +17,7 @@ int DbTransaction::error;
 bool DbTransaction::hasTransaction;
 QList<quint64> DbTransaction::items;
 
-quint64 DatabaseStamp;
+quint64 DbTransaction::DatabaseStamp;
 
 void DbTransaction::debug(const char *func, const char *file, int line)
 {
diff --git a/lib/sql.h b/lib/sql.h
index 3303ccf7..9c403bc4 100644
--- a/lib/sql.h
+++ b/lib/sql.h
@@ -34,6 +34,7 @@ class DbTransaction
 		bool commit(const char *file, int line);
 		bool rollback(const char *file, int line);
 		bool done(QSqlError e, const char *file, int line);
+		static quint64 DatabaseStamp;
 		static bool active()
 		{
 			return mutex > 0;
diff --git a/widgets/MW_database.cpp b/widgets/MW_database.cpp
index a32180f1..cc21684c 100644
--- a/widgets/MW_database.cpp
+++ b/widgets/MW_database.cpp
@@ -25,7 +25,7 @@
 
 QSqlError MainWindow::initSqlDB()
 {
-	QStringList schemas[6];
+	QStringList schemas[7];
 
 #include "database_schema.cpp"
 
@@ -274,6 +274,8 @@ int MainWindow::init_database(QString dbName)
 		certs = new db_x509(this);
 		temps = new db_temp(this);
 		crls = new db_crl(this);
+		check_oom(keys && reqs && certs && temps && crls);
+		models << keys << reqs << certs << temps << crls;
 	}
 	catch (errorEx &err) {
 		Error(err);
@@ -325,9 +327,42 @@ int MainWindow::init_database(QString dbName)
 	}
 	dbindex->setText(tr("Database") + ": " + dbName);
 	currentDB = dbName;
+	dbTimer = startTimer(1500);
 	return ret;
 }
 
+void MainWindow::timerEvent(QTimerEvent *event)
+{
+	quint64 stamp;
+	if (event->timerId() != dbTimer)
+		return;
+	XSqlQuery q;
+	SQL_PREPARE(q, "SELECT MAX(stamp) from items");
+	q.exec();
+	if (!q.first())
+		return;
+	stamp = q.value(0).toULongLong();
+	q.finish();
+	qDebug() << "Stamp" << stamp
+		 << "DatabaseStamp" << DbTransaction::DatabaseStamp;
+
+	if (stamp > DbTransaction::DatabaseStamp) {
+		SQL_PREPARE(q, "SELECT DISTINCT type FROM items WHERE stamp=?");
+		q.bindValue(0, stamp);
+		q.exec();
+
+		QList<enum pki_type> typelist;
+		while (q.next())
+			typelist << (enum pki_type)q.value(0).toInt();
+
+		q.finish();
+		qDebug() << "CHANGED" << typelist;
+		foreach(db_base *model, models)
+			model->reloadContainer(typelist);
+	}
+	DbTransaction::DatabaseStamp = stamp;
+}
+
 void MainWindow::dump_database()
 {
 	QString dirname = QFileDialog::getExistingDirectory(
@@ -464,6 +499,7 @@ void MainWindow::close_database()
 		Settings.clear();
 		return;
 	}
+	killTimer(dbTimer);
 	qDebug("Closing database: %s", QString2filename(currentDB));
 	Settings["mw_geometry"] = QString("%1,%2,%3")
 			.arg(size().width())
@@ -480,16 +516,8 @@ void MainWindow::close_database()
 	tempView->setModel();
 	crlView->setModel();
 
-	if (crls)
-		delete(crls);
-	if (reqs)
-		delete(reqs);
-	if (certs)
-		delete(certs);
-	if (temps)
-		delete(temps);
-	if (keys)
-		delete(keys);
+	qDeleteAll(models.begin(), models.end());
+	models.clear();
 
 	db_base::flushLookup();
 	reqs = NULL;
diff --git a/widgets/MainWindow.cpp b/widgets/MainWindow.cpp
index 79a54cc8..ff9845fd 100644
--- a/widgets/MainWindow.cpp
+++ b/widgets/MainWindow.cpp
@@ -915,16 +915,13 @@ void MainWindow::generateDHparam()
 void MainWindow::changeEvent(QEvent *event)
 {
 	if (event->type() == QEvent::LanguageChange) {
-		QList<db_base*> models;
 		retranslateUi(this);
 		dn_translations_setup();
 		init_menu();
 		update_history_menu();
-		models << keys << reqs << certs << crls << temps;
-		foreach(db_base *model, models) {
-			if (model)
-				model->updateHeaders();
-		}
+		foreach(db_base *model, models)
+			model->updateHeaders();
+
 		if (!currentDB.isEmpty())
 			dbindex->setText(tr("Database") + ": " + currentDB);
 		searchEdit->setPlaceholderText(tr("Search"));
diff --git a/widgets/MainWindow.h b/widgets/MainWindow.h
index a3ac4e87..231b3b06 100644
--- a/widgets/MainWindow.h
+++ b/widgets/MainWindow.h
@@ -76,7 +76,7 @@ class MainWindow: public QMainWindow, public Ui::MainWindow
 		void checkDB();
 		QSqlError initSqlDB();
 		QString openSqlDB(QString dbName);
-		QTimer *eachSecond;
+		QList<db_base*> models;
 
 	protected:
 		void init_images();
@@ -87,6 +87,8 @@ class MainWindow: public QMainWindow, public Ui::MainWindow
 		QString homedir;
 		int changeDB(QString fname);
 		void keyPressEvent(QKeyEvent *e);
+		int dbTimer;
+		void timerEvent(QTimerEvent *event);
 
 	public:
 		static db_x509 *certs;
diff --git a/widgets/Options.cpp b/widgets/Options.cpp
index 1aea0a32..6409a686 100644
--- a/widgets/Options.cpp
+++ b/widgets/Options.cpp
@@ -210,7 +210,6 @@ void Options::on_searchPkcs11_clicked(void)
 
 void Options::Pkcs11ItemChanged(QListWidgetItem *item)
 {
-TRACE
 	pkcs11List->blockSignals(true);
 	pkcs11_lib *l = pkcs11::get_libs().get_lib(item->text());
 	qDebug() << item->text() << item->checkState() << l->isEnabled() << l->isLoaded();
diff --git a/widgets/database_schema.cpp b/widgets/database_schema.cpp
index e6cf9ea1..48b0be75 100644
--- a/widgets/database_schema.cpp
+++ b/widgets/database_schema.cpp
@@ -310,6 +310,12 @@
 << "UPDATE settings SET value='6' WHERE key_='schema'"
 	;
 
+	schemas[6]
+<< "ALTER TABLE items ADD del SMALLINT NOT NULL DEFAULT 0"
+<< "CREATE INDEX i_items_del ON items (del)"
+<< "UPDATE settings SET value='7' WHERE key_='schema'"
+	;
+
 /* When adding new tables or views, also add them to the list
  * in XSqlQuery::rewriteQuery(QString) in lib/sql.cpp
  */