wf-background: Load the next background when receiving SIGUSR1.

Author: lcolitti

src/background/background.cpp

@@ -15,6 +15,7 @@
 
 #include <gtk-utils.hpp>
 #include <gtk-layer-shell.h>
+#include <glib-unix.h>
 
 #include "background.hpp"
 
@@ -330,6 +331,7 @@ class WayfireBackgroundApp : public WayfireShellApp
     {
         WayfireShellApp::instance =
             std::make_unique<WayfireBackgroundApp>(argc, argv);
+        g_unix_signal_add(SIGUSR1, sigusr1_handler, (void*)instance.get());
         instance->run();
     }
 
@@ -343,6 +345,16 @@ class WayfireBackgroundApp : public WayfireShellApp
     {
         backgrounds.erase(output);
     }
+
+    static gboolean sigusr1_handler(void *instance)
+    {
+        for (const auto& [_, bg] : ((WayfireBackgroundApp*)instance)->backgrounds)
+        {
+            bg->change_background();
+        }
+
+        return TRUE;
+    }
 };
 
 int main(int argc, char **argv)

src/background/background.hpp

@@ -60,7 +60,6 @@ class WayfireBackground
 
     Glib::RefPtr<Gdk::Pixbuf> create_from_file_safe(std::string path);
     bool background_transition_frame(int timer);
-    bool change_background();
     bool load_images_from_dir(std::string path);
     bool load_next_background(Glib::RefPtr<Gdk::Pixbuf> & pbuf, std::string & path);
     void reset_background();
@@ -71,4 +70,5 @@ class WayfireBackground
 
   public:
     WayfireBackground(WayfireShellApp *app, WayfireOutput *output);
+    bool change_background();
 };