Treat permanent redirects after temporary redirects as temporary.

Example:
http://example.com/ returns 302 with Location: http://example.com/1
http://example.com/1 returns 301 with Location: http://example.com/2

http://example.com/ will not be overwritten in the config file.

src/document.cpp

@@ -61,7 +61,7 @@ Document::~Document()
     RestClient::disable();
 }
 
-void Document::download(const string &uri)
+void Document::download(const string &uri, const bool temp_redirect)
 {
     RestClient::Connection connection{uri};
     connection.SetUserAgent(string("mastorss/").append(version));
@@ -80,6 +80,10 @@ void Document::download(const string &uri)
     case 301:
     case 308:
     {
+        if (temp_redirect)
+        {
+            goto temporary_redirect;
+        }
         _profiledata.feedurl = extract_location(response.headers);
         if (_profiledata.feedurl.empty())
         {
@@ -96,6 +100,7 @@ void Document::download(const string &uri)
     case 303:
     case 307:
     {
+    temporary_redirect:
         const string newuri{extract_location(response.headers)};
         if (newuri.empty())
         {
@@ -104,7 +109,7 @@ void Document::download(const string &uri)
 
         BOOST_LOG_TRIVIAL(debug) << "Feed has new location (temporary): "
                                  << _profiledata.feedurl;
-        download(newuri);
+        download(newuri, true);
         break;
     }
     case -1:

src/document.hpp

@@ -63,8 +63,6 @@ public:
 
     list<Item> new_items;
 
-    void download();
-    void download(const string &uri);
     void parse();
 
 private:
@@ -73,6 +71,19 @@ private:
     string _raw_doc;
     list<string> _watchwords;
 
+    void download();
+    /*!
+     *  @brief  Download document.
+     *
+     *  @param  uri           The URI to download.
+     *  @param  temp_redirect `true` if this is an temporary redirect.
+     *
+     *  The argument `temp_redirect` is there for cases where the original URI
+     *  is redirected temporarily, and the new URI is redirected permanently.
+     *
+     *  @since  0.10.0
+     */
+    void download(const string &uri, const bool temp_redirect = false);
     void parse_rss(const pt::ptree &tree);
     [[nodiscard]]
     string remove_html(string html) const;