[gnome-software] Allow plugins to conflict with each other

[Richard Hughes <rhughes src gnome org>]

commit c99ff29f379e7736d5c33d14f38d2c5359ad8560
Author: Richard Hughes <richard hughsie com>
Date:   Thu Mar 24 20:14:39 2016 +0000

    Allow plugins to conflict with each other
    
    The plugin defining the conflict is prefered, and if mutual then the lower
    priority plugin is automatically disabled.

 src/gs-plugin-loader.c                 |   25 +++++++++++++++++++++++++
 src/gs-plugin.h                        |    2 ++
 src/plugins/gs-plugin-ostree.c         |   19 +++++++++++++++++++
 src/plugins/gs-plugin-ubuntu-reviews.c |   12 ++++++++++++
 4 files changed, 58 insertions(+), 0 deletions(-)
---
diff --git a/src/gs-plugin-loader.c b/src/gs-plugin-loader.c
index 292c8a9..2e271b8 100644
--- a/src/gs-plugin-loader.c
+++ b/src/gs-plugin-loader.c
@@ -2907,6 +2907,7 @@ gs_plugin_loader_open_plugin (GsPluginLoader *plugin_loader,
        GModule *module;
        GsPluginGetNameFunc plugin_name = NULL;
        GsPluginGetDepsFunc plugin_deps = NULL;
+       GsPluginGetDepsFunc plugin_conflicts = NULL;
        GsPlugin *plugin = NULL;
 
        module = g_module_open (filename, 0);
@@ -2930,6 +2931,9 @@ gs_plugin_loader_open_plugin (GsPluginLoader *plugin_loader,
        (void) g_module_symbol (module,
                                "gs_plugin_get_deps",
                                (gpointer *) &plugin_deps);
+       g_module_symbol (module,
+                        "gs_plugin_get_conflicts",
+                        (gpointer *) &plugin_conflicts);
 
        /* print what we know */
        plugin = g_slice_new0 (GsPlugin);
@@ -2938,6 +2942,7 @@ gs_plugin_loader_open_plugin (GsPluginLoader *plugin_loader,
        plugin->pixbuf_size = 64;
        plugin->priority = 0.f;
        plugin->deps = plugin_deps != NULL ? plugin_deps (plugin) : NULL;
+       plugin->conflicts = plugin_conflicts != NULL ? plugin_conflicts (plugin) : NULL;
        plugin->name = g_strdup (plugin_name ());
        plugin->locale = priv->locale;
        plugin->status_update_fn = gs_plugin_loader_status_update_cb;
@@ -3125,6 +3130,26 @@ gs_plugin_loader_setup (GsPluginLoader *plugin_loader, GError **error)
        /* run the plugins */
        gs_plugin_loader_run (plugin_loader, "gs_plugin_initialize");
 
+       /* check for conflicts */
+       for (i = 0; i < priv->plugins->len; i++) {
+               plugin = g_ptr_array_index (priv->plugins, i);
+               if (!plugin->enabled)
+                       continue;
+               if (plugin->conflicts == NULL)
+                       continue;
+               for (j = 0; plugin->conflicts[j] != NULL && !changes; j++) {
+                       dep = gs_plugin_loader_find_plugin (plugin_loader,
+                                                           plugin->conflicts[j]);
+                       if (dep == NULL)
+                               continue;
+                       if (!dep->enabled)
+                               continue;
+                       g_debug ("disabling %s as conflicts with %s",
+                                dep->name, plugin->name);
+                       dep->enabled = FALSE;
+               }
+       }
+
        /* now we can load the install-queue */
        if (!load_install_queue (plugin_loader, error))
                return FALSE;
diff --git a/src/gs-plugin.h b/src/gs-plugin.h
index 6955bf5..c76c9b5 100644
--- a/src/gs-plugin.h
+++ b/src/gs-plugin.h
@@ -65,6 +65,7 @@ struct GsPlugin {
        GModule                 *module;
        gdouble                  priority;      /* largest number gets run first */
        const gchar             **deps;         /* allow-none */
+       const gchar             **conflicts;    /* allow-none */
        gboolean                 enabled;
        gchar                   *name;
        GsPluginPrivate         *priv;
@@ -220,6 +221,7 @@ gboolean     gs_plugin_add_search_what_provides     (GsPlugin       *plugin,
                                                         GCancellable   *cancellable,
                                                         GError         **error);
 const gchar    **gs_plugin_get_deps                    (GsPlugin       *plugin);
+const gchar    **gs_plugin_get_conflicts               (GsPlugin       *plugin);
 gboolean        gs_plugin_add_installed                (GsPlugin       *plugin,
                                                         GList          **list,
                                                         GCancellable   *cancellable,
diff --git a/src/plugins/gs-plugin-ostree.c b/src/plugins/gs-plugin-ostree.c
index 7d4ad2b..b923733 100644
--- a/src/plugins/gs-plugin-ostree.c
+++ b/src/plugins/gs-plugin-ostree.c
@@ -58,6 +58,25 @@ gs_plugin_initialize (GsPlugin *plugin)
 }
 
 /**
+ * gs_plugin_get_conflicts:
+ */
+const gchar **
+gs_plugin_get_conflicts (GsPlugin *plugin)
+{
+       static const gchar *deps[] = {
+               "packagekit",
+               "packagekit-history",
+               "packagekit-offline",
+               "packagekit-origin",
+               "packagekit-proxy",
+               "packagekit-refine",
+               "packagekit-refresh",
+               "systemd-updates",
+               NULL };
+       return deps;
+}
+
+/**
  * gs_plugin_destroy:
  */
 void
diff --git a/src/plugins/gs-plugin-ubuntu-reviews.c b/src/plugins/gs-plugin-ubuntu-reviews.c
index 79f0239..02d783a 100644
--- a/src/plugins/gs-plugin-ubuntu-reviews.c
+++ b/src/plugins/gs-plugin-ubuntu-reviews.c
@@ -84,6 +84,18 @@ gs_plugin_get_deps (GsPlugin *plugin)
        return deps;
 }
 
+/**
+ * gs_plugin_get_conflicts:
+ */
+const gchar **
+gs_plugin_get_conflicts (GsPlugin *plugin)
+{
+       static const gchar *deps[] = {
+               "odrs",
+               NULL };
+       return deps;
+}
+
 void
 gs_plugin_destroy (GsPlugin *plugin)
 {