From 3c47354e0623c5236b00e626f6de3a26d2d1d073 Mon Sep 17 00:00:00 2001
From: Martchus <martchus@gmx.net>
Date: Sun, 29 Jan 2017 23:10:21 +0100
Subject: [PATCH] Follow redirection when downloading db

---
 lib/alpm/alpmdatabase.cpp | 30 ++++++++++++++++++++++++++----
 lib/alpm/alpmdatabase.h   |  2 ++
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/lib/alpm/alpmdatabase.cpp b/lib/alpm/alpmdatabase.cpp
index 564f3c8..c560fb0 100644
--- a/lib/alpm/alpmdatabase.cpp
+++ b/lib/alpm/alpmdatabase.cpp
@@ -204,12 +204,16 @@ PackageDetailAvailability AlpmDatabase::requestsRequired(PackageDetail packageDe
 
 QNetworkRequest AlpmDatabase::regularDatabaseRequest()
 {
-    return QNetworkRequest(QUrl(serverUrls().front() % QChar('/') % name() % QStringLiteral(".db")));
+    return QNetworkRequest(m_filesRedirs.isEmpty()
+                ? (QUrl(serverUrls().front() % QChar('/') % name() % QStringLiteral(".db")))
+                : m_regularRedirs.back());
 }
 
 QNetworkRequest AlpmDatabase::filesDatabaseRequest()
 {
-    return QNetworkRequest(QUrl(serverUrls().front() % QChar('/') % name() % QStringLiteral(".files")));
+    return QNetworkRequest(m_filesRedirs.isEmpty()
+                ? (QUrl(serverUrls().front() % QChar('/') % name() % QStringLiteral(".files")))
+                : m_filesRedirs.back());
 }
 
 /*!
@@ -266,8 +270,25 @@ void AlpmDatabase::databaseDownloadFinished()
     auto *reply = static_cast<QNetworkReply *>(sender());
     reply->deleteLater();
     bool filesDatabase =  reply->property("filesDatabase").toBool();
+    const QString redirTarget = reply->attribute(QNetworkRequest::RedirectionTargetAttribute).toString();
     QReadLocker locker(lock());
-    if(reply->error() == QNetworkReply::NoError) {
+    switch(reply->error()) {
+    case QNetworkReply::NoError: {
+        if(!redirTarget.isEmpty()) {
+            if((!filesDatabase && m_regularRedirs.contains(redirTarget)) || (filesDatabase && m_filesRedirs.contains(redirTarget))) {
+                cerr << "Redirection-loop for database file [" << name().toLocal8Bit().data() << "]" << endl;
+                removeBusyFlag();
+                return;
+            }
+
+            (filesDatabase ? m_filesRedirs : m_regularRedirs) << redirTarget;
+            cerr << "Redirection target for database file [" << name().toLocal8Bit().data() << "] available: " << redirTarget.toLocal8Bit().data() << endl;
+
+            locker.unlock();
+            downloadDatabase(m_downloadTargetDir, filesDatabase);
+        }
+        m_filesRedirs.clear();
+
         QString newDatabasePath;
         cerr << "Downloaded database file for [" << name().toLocal8Bit().data() << "] successfully." << endl;
         newDatabasePath = m_downloadTargetDir % QChar('/') % name() % (filesDatabase ? QStringLiteral(".files") : QStringLiteral(".db"));
@@ -295,7 +316,7 @@ void AlpmDatabase::databaseDownloadFinished()
             cerr << "An IO error occured when storing database file for [" << name().toLocal8Bit().data() << "]: Unable to create/write output file." << endl;
             removeBusyFlag();
         }
-    } else {
+    } default:
         cerr << "An error occured when dwonloading database file for [" << name().toLocal8Bit().data() << "]: " << reply->errorString().toLocal8Bit().data() << endl;
         if(filesDatabase && reply->error() == QNetworkReply::ContentNotFoundError) {
             cerr << "-> Attempting to download regular database file instead of files database file." << endl;
@@ -304,6 +325,7 @@ void AlpmDatabase::databaseDownloadFinished()
         } else {
             removeBusyFlag();
         }
+        break;
     }
 }
 
diff --git a/lib/alpm/alpmdatabase.h b/lib/alpm/alpmdatabase.h
index eb6c00d..a01461c 100644
--- a/lib/alpm/alpmdatabase.h
+++ b/lib/alpm/alpmdatabase.h
@@ -90,6 +90,8 @@ private:
 
     QString m_dbPath;
     QString m_downloadTargetDir;
+    QStringList m_regularRedirs;
+    QStringList m_filesRedirs;
 };
 
 /*!