[libcalamares] Refactor synchronous get

- Add timeout support
 - Refactor into a static helper method

src/libcalamares/network/Manager.cpp

@@ -22,6 +22,7 @@
 #include <QNetworkAccessManager>
 #include <QNetworkReply>
 #include <QNetworkRequest>
+#include <QTimer>
 
 namespace CalamaresUtils
 {
@@ -98,6 +99,28 @@ Manager::setCheckHasInternetUrl( const QUrl& url )
     d->m_hasInternetUrl = url;
 }
 
+static QNetworkReply*
+synchronousRun( const std::unique_ptr< QNetworkAccessManager >& nam, const QUrl& url, const RequestOptions& options )
+{
+    QNetworkRequest request = QNetworkRequest( url );
+    QNetworkReply* reply = nam->get( request );
+    QEventLoop loop;
+    QTimer timer;
+
+    options.applyToRequest( &request );
+    if ( options.hasTimeout() )
+    {
+        timer.setSingleShot( true );
+        QObject::connect( &timer, &QTimer::timeout, &loop, &QEventLoop::quit );
+        timer.start( options.timeout() );
+    }
+
+    QObject::connect( reply, &QNetworkReply::finished, &loop, &QEventLoop::quit );
+    loop.exec();
+    reply->deleteLater();
+    return reply;
+}
+
 bool
 Manager::synchronousPing( const QUrl& url, const RequestOptions& options )
 {
@@ -106,13 +129,7 @@ Manager::synchronousPing( const QUrl& url, const RequestOptions& options )
         return false;
     }
 
-    QNetworkRequest request = QNetworkRequest( url );
+    auto reply = synchronousRun( d->m_nam, url, options );
-    QNetworkReply* reply = d->m_nam->get( request );
-    QEventLoop loop;
-    options.applyToRequest( &request );
-    connect( reply, &QNetworkReply::finished, &loop, &QEventLoop::quit );
-    loop.exec();
-    reply->deleteLater();
     return reply->bytesAvailable();
 }
 
@@ -124,13 +141,7 @@ Manager::synchronousGet( const QUrl& url, const RequestOptions& options )
         return QByteArray();
     }
 
-    QNetworkRequest request( url );
+    auto reply = synchronousRun( d->m_nam, url, options );
-    QNetworkReply* reply = d->m_nam->get( request );
-    QEventLoop loop;
-    options.applyToRequest( &request );
-    connect( reply, &QNetworkReply::finished, &loop, &QEventLoop::quit );
-    loop.exec();
-    reply->deleteLater();
     return reply->readAll();
 }
 

src/libcalamares/network/Manager.h

@@ -37,6 +37,8 @@ namespace Network
 class DLLEXPORT RequestOptions
 {
 public:
+    using milliseconds = std::chrono::milliseconds;
+
     enum Flag
     {
         FollowRedirect = 0x1,
@@ -50,7 +52,7 @@ public:
     {
     }
 
-    RequestOptions( Flags f, std::chrono::milliseconds timeout = std::chrono::milliseconds( -1 ) )
+    RequestOptions( Flags f, milliseconds timeout = milliseconds( -1 ) )
         : m_flags( f )
         , m_timeout( timeout )
     {
@@ -58,9 +60,12 @@ public:
 
     void applyToRequest( QNetworkRequest* ) const;
 
+    bool hasTimeout() const { return m_timeout > milliseconds( 0 ); }
+    auto timeout() const { return m_timeout; }
+
 private:
     Flags m_flags;
-    std::chrono::milliseconds m_timeout;
+    milliseconds m_timeout;
 };
 
 Q_DECLARE_OPERATORS_FOR_FLAGS( RequestOptions::Flags );