From b28d0f63ec07880b191e83e12385a2befaac5620 Mon Sep 17 00:00:00 2001
From: Martin Kleusberg <mkleusberg@gmail.com>
Date: Fri, 10 Aug 2018 19:09:12 +0200
Subject: [PATCH] Show SQLite and SQLCipher version in About dialog when using
 SQLCipher

See issue #1474.
---
 src/AboutDialog.cpp | 15 +++++++++------
 src/sqlitedb.cpp    | 26 ++++++++++++++++++++++++++
 src/sqlitedb.h      |  3 +++
 3 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/src/AboutDialog.cpp b/src/AboutDialog.cpp
index 12fe718d..b3907ddf 100644
--- a/src/AboutDialog.cpp
+++ b/src/AboutDialog.cpp
@@ -1,6 +1,6 @@
 #include "AboutDialog.h"
 #include "ui_AboutDialog.h"
-#include "sqlite.h"
+#include "sqlitedb.h"
 #include "Application.h"
 
 AboutDialog::AboutDialog(QWidget *parent) :
@@ -11,13 +11,16 @@ AboutDialog::AboutDialog(QWidget *parent) :
     this->setFixedSize(this->width(), this->height());
     this->setWindowFlags(this->windowFlags() & ~Qt::WindowContextHelpButtonHint);
 
+    QString sqlite_version, sqlcipher_version;
+    DBBrowserDB::getSqliteVersion(sqlite_version, sqlcipher_version);
+    if(sqlcipher_version.isNull())
+        sqlite_version = tr("SQLite Version ") + sqlite_version;
+    else
+        sqlite_version = tr("SQLCipher Version ") + sqlcipher_version + tr(" (based on SQLite %1)").arg(sqlite_version);
+
     ui->label_version->setText(tr("Version ") + Application::versionString() + "\n\n" +
                                tr("Qt Version ") + QT_VERSION_STR + "\n\n" +
-#ifdef ENABLE_SQLCIPHER
-                               tr("SQLCipher based on SQLite Version ") + SQLITE_VERSION
-#else
-                               tr("SQLite Version ") + SQLITE_VERSION
-#endif
+                               sqlite_version
                                );
 }
 
diff --git a/src/sqlitedb.cpp b/src/sqlitedb.cpp
index ee5bd744..c9e3b353 100644
--- a/src/sqlitedb.cpp
+++ b/src/sqlitedb.cpp
@@ -375,6 +375,32 @@ bool DBBrowserDB::tryEncryptionSettings(const QString& filePath, bool* encrypted
     }
 }
 
+void DBBrowserDB::getSqliteVersion(QString& sqlite, QString& sqlcipher)
+{
+    sqlite = QString(SQLITE_VERSION);
+
+    // The SQLCipher version must be queried via a pragma and for a pragma we need a database connection.
+    // Because we want to be able to query the SQLCipher version without opening a database file first, we
+    // open a separate connection to an in-memory database here.
+    sqlcipher = QString();
+#ifdef ENABLE_SQLCIPHER
+    sqlite3* dummy;
+    if(sqlite3_open(":memory:", &dummy) == SQLITE_OK)
+    {
+        sqlite3_stmt* stmt;
+        if(sqlite3_prepare_v2(dummy, "PRAGMA cipher_version", -1, &stmt, nullptr) == SQLITE_OK)
+        {
+            if(sqlite3_step(stmt) == SQLITE_ROW)
+                sqlcipher = QByteArray(static_cast<const char*>(sqlite3_column_blob(stmt, 0)), sqlite3_column_bytes(stmt, 0));
+
+            sqlite3_finalize(stmt);
+        }
+
+        sqlite3_close(dummy);
+    }
+#endif
+}
+
 bool DBBrowserDB::setSavepoint(const QString& pointname)
 {
     if(!isOpen())
diff --git a/src/sqlitedb.h b/src/sqlitedb.h
index 573b1917..641530b6 100644
--- a/src/sqlitedb.h
+++ b/src/sqlitedb.h
@@ -61,6 +61,9 @@ public:
     bool create ( const QString & db);
     bool close();
 
+    // This returns the SQLite version as well as the SQLCipher if DB4S is compiled with encryption support
+    static void getSqliteVersion(QString& sqlite, QString& sqlcipher);
+
     typedef std::unique_ptr<sqlite3, DatabaseReleaser> db_pointer_type;
 
     /**