search: done loading signal only if not restarting engine

It was working as:
- Search directory starts a new search
- Search engine starts all search providers, each one in its
own thread.
- User changes query
- Search engine stops all search providers
- Searchs providers, since they are in its own thread, cancel
in a unknown time.
- Search directory starts a new search, even before all providers
are finished.
- Search engine is marked as need to restart.
- Search providers finished.
- Search engine emits finished signal, since all search providers
now are stopped.
- Clients doesn't have a way to know if the engine
actually finished searching the current search, or the previous
search that the client asked to stop. That might confuse clients
if they ask for results.
- Search engine restart the search providers without noticing the
client, that thinks that the latest search it started was finished
already.

So to fix this confusion, only report that the engine actually finished
if the engine is not going to restart the search providers.
In this way a client can start a batch of consecutive searches without
the risk of getting search finished signals from previous searches.
Clients now will always get the search-finished signal of the
latest search they started.

10 files changed, 158 insertions, 16 deletions

diff --git a/libnautilus-private/Makefile.am b/libnautilus-private/Makefile.am
index c0753e541..92c601451 100644
--- a/libnautilus-private/Makefile.am
+++ b/libnautilus-private/Makefile.am
@@ -17,12 +17,28 @@ AM_CPPFLAGS = 						\
 	-DNAUTILUS_EXTENSIONDIR=\""$(libdir)/nautilus/extensions-3.0"\" \
 	$(NULL)
 
+# Basic sanity checks
+$(if $(GLIB_MKENUMS),,$(error Need to define GLIB_MKENUMS))
+
 if ENABLE_TRACKER
 nautilus_tracker_engine_sources = \
 	nautilus-search-engine-tracker.c \
 	nautilus-search-engine-tracker.h
 endif
 
+BUILT_SOURCES = 					\
+	nautilus-private-enum-types.h			\
+	nautilus-private-enum-types.c			\
+	$(NULL)
+
+ENUM_TYPES = nautilus-search-provider.h
+
+nautilus-private-enum-types.h: nautilus-private-enum-types.h.template $(ENUM_TYPES) $(GLIB_MKENUMS)
+	$(AM_V_GEN) (cd $(srcdir) && $(GLIB_MKENUMS) --template nautilus-private-enum-types.h.template $(ENUM_TYPES)) > $@
+
+nautilus-private-enum-types.c: nautilus-private-enum-types.c.template $(ENUM_TYPES) $(GLIB_MKENUMS)
+	$(AM_V_GEN) (cd $(srcdir) && $(GLIB_MKENUMS) --template nautilus-private-enum-types.c.template $(ENUM_TYPES)) > $@
+
 libnautilus_private_la_LDFLAGS =	\
 	-no-undefined			\
 	$(NULL)
@@ -186,6 +202,8 @@ EXTRA_DIST =				\
 	nautilus.convert		\
 	$(gsettingsschema_in_files)     \
 	$(TRACKER_SOURCES)		\
+	nautilus-private-enum-types.h.template	\
+	nautilus-private-enum-types.c.template	\
 	$(NULL)
 
 CLEANFILES = \
diff --git a/libnautilus-private/nautilus-private-enum-types.c.template b/libnautilus-private/nautilus-private-enum-types.c.template
new file mode 100644
index 000000000..4acb2d8a8
--- /dev/null
+++ b/libnautilus-private/nautilus-private-enum-types.c.template
@@ -0,0 +1,40 @@
+/*** BEGIN file-header ***/
+#include "nautilus-private-enum-types.h"
+
+/*** END file-header ***/
+
+/*** BEGIN file-production ***/
+/* enumerations from "@filename@" */
+#include "@filename@"
+
+/*** END file-production ***/
+
+/*** BEGIN value-header ***/
+GType
+@enum_name@_get_type (void)
+{
+	static GType the_type = 0;
+
+	if (the_type == 0)
+	{
+		static const G@Type@Value values[] = {
+/*** END value-header ***/
+
+/*** BEGIN value-production ***/
+			{ @VALUENAME@,
+			  "@VALUENAME@",
+			  "@valuenick@" },
+/*** END value-production ***/
+
+/*** BEGIN value-tail ***/
+			{ 0, NULL, NULL }
+		};
+		the_type = g_@type@_register_static (
+				g_intern_static_string ("@EnumName@"),
+				values);
+	}
+	return the_type;
+}
+
+/*** END value-tail ***/
+
diff --git a/libnautilus-private/nautilus-private-enum-types.h.template b/libnautilus-private/nautilus-private-enum-types.h.template
new file mode 100644
index 000000000..c4dbbe7b6
--- /dev/null
+++ b/libnautilus-private/nautilus-private-enum-types.h.template
@@ -0,0 +1,27 @@
+/*** BEGIN file-header ***/
+#ifndef __NAUTILUS_PRIVATE_ENUM_TYPES_H__
+#define __NAUTILUS_PRIVATE_ENUM_TYPES_H__
+
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+/*** END file-header ***/
+
+/*** BEGIN file-production ***/
+/* Enumerations from "@filename@" */
+
+/*** END file-production ***/
+
+/*** BEGIN enumeration-production ***/
+#define @ENUMPREFIX@_TYPE_@ENUMSHORT@	(@enum_name@_get_type())
+GType @enum_name@_get_type	(void) G_GNUC_CONST;
+
+/*** END enumeration-production ***/
+
+/*** BEGIN file-tail ***/
+G_END_DECLS
+
+#endif /* __NAUTILUS_PRIVATE_ENUM_TYPES_H__ */
+/*** END file-tail ***/
+
diff --git a/libnautilus-private/nautilus-search-directory.c b/libnautilus-private/nautilus-search-directory.c
index 836b0d3f4..c0141b65e 100644
--- a/libnautilus-private/nautilus-search-directory.c
+++ b/libnautilus-private/nautilus-search-directory.c
@@ -588,10 +588,26 @@ search_engine_error (NautilusSearchEngine *engine, const char *error_message, Na
 }
 
 static void
-search_engine_finished (NautilusSearchEngine *engine, NautilusSearchDirectory *search)
-{
-	search_directory_ensure_loaded (search);
-	nautilus_directory_emit_done_loading (NAUTILUS_DIRECTORY (search));
+search_engine_finished (NautilusSearchEngine         *engine,
+                        NautilusSearchProviderStatus  status,
+                        NautilusSearchDirectory      *search)
+{
+        /* If the search engine is going to restart means it finished an old search
+         * that was stopped or cancelled.
+         * Don't emit the done loading signal in this case, since this means the search
+         * directory tried to start a new search before all the search providers were finished
+         * in the search engine.
+         * If we emit the done-loading signal in this situation the client will think
+         * that it finished the current search, not an old one like it's actually
+         * happening. */
+        if (status == NAUTILUS_SEARCH_PROVIDER_STATUS_NORMAL) {
+                search_directory_ensure_loaded (search);
+	        nautilus_directory_emit_done_loading (NAUTILUS_DIRECTORY (search));
+        } else if (status == NAUTILUS_SEARCH_PROVIDER_STATUS_RESTARTING) {
+                /* Remove file monitors of the files from an old search that just
+                 * actually finished */
+                reset_file_list (search);
+        }
 }
 
 static void
diff --git a/libnautilus-private/nautilus-search-engine-model.c b/libnautilus-private/nautilus-search-engine-model.c
index 22a644e2e..8648cf5e3 100644
--- a/libnautilus-private/nautilus-search-engine-model.c
+++ b/libnautilus-private/nautilus-search-engine-model.c
@@ -88,8 +88,9 @@ search_finished (NautilusSearchEngineModel *model)
 	}
 
 	model->details->query_pending = FALSE;
-	nautilus_search_provider_finished (NAUTILUS_SEARCH_PROVIDER (model));
 	DEBUG ("Model engine finished");
+	nautilus_search_provider_finished (NAUTILUS_SEARCH_PROVIDER (model),
+                                           NAUTILUS_SEARCH_PROVIDER_STATUS_NORMAL);
 	g_object_unref (model);
 
 	return FALSE;
diff --git a/libnautilus-private/nautilus-search-engine-simple.c b/libnautilus-private/nautilus-search-engine-simple.c
index 5bcea4956..33180fbf3 100644
--- a/libnautilus-private/nautilus-search-engine-simple.c
+++ b/libnautilus-private/nautilus-search-engine-simple.c
@@ -144,7 +144,8 @@ search_thread_done_idle (gpointer user_data)
 	        DEBUG ("Simple engine finished");
         }
 	engine->details->active_search = NULL;
-	nautilus_search_provider_finished (NAUTILUS_SEARCH_PROVIDER (engine));
+	nautilus_search_provider_finished (NAUTILUS_SEARCH_PROVIDER (engine),
+                                           NAUTILUS_SEARCH_PROVIDER_STATUS_NORMAL);
 
 	search_thread_data_free (data);
 
diff --git a/libnautilus-private/nautilus-search-engine-tracker.c b/libnautilus-private/nautilus-search-engine-tracker.c
index 85e4122ff..6120448d7 100644
--- a/libnautilus-private/nautilus-search-engine-tracker.c
+++ b/libnautilus-private/nautilus-search-engine-tracker.c
@@ -115,7 +115,8 @@ search_finished (NautilusSearchEngineTracker *tracker,
 	        DEBUG ("Tracker engine error %s", error->message);
 		nautilus_search_provider_error (NAUTILUS_SEARCH_PROVIDER (tracker), error->message);
 	} else {
-		nautilus_search_provider_finished (NAUTILUS_SEARCH_PROVIDER (tracker));
+		nautilus_search_provider_finished (NAUTILUS_SEARCH_PROVIDER (tracker),
+                                                   NAUTILUS_SEARCH_PROVIDER_STATUS_NORMAL);
                 if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED)) {
 	                DEBUG ("Tracker engine finished and cancelled");
                 } else {
diff --git a/libnautilus-private/nautilus-search-engine.c b/libnautilus-private/nautilus-search-engine.c
index a48b61a07..0ae369a96 100644
--- a/libnautilus-private/nautilus-search-engine.c
+++ b/libnautilus-private/nautilus-search-engine.c
@@ -188,12 +188,14 @@ check_providers_status (NautilusSearchEngine *engine)
 		nautilus_search_provider_error (NAUTILUS_SEARCH_PROVIDER (engine),
 						_("Unable to complete the requested search"));
 	} else {
-		nautilus_search_provider_finished (NAUTILUS_SEARCH_PROVIDER (engine));
                 if (engine->details->restart) {
 		        DEBUG ("Search engine finished and restarting");
                 } else {
 		        DEBUG ("Search engine finished");
                 }
+		nautilus_search_provider_finished (NAUTILUS_SEARCH_PROVIDER (engine),
+                                                   engine->details->restart ? NAUTILUS_SEARCH_PROVIDER_STATUS_RESTARTING :
+                                                                              NAUTILUS_SEARCH_PROVIDER_STATUS_NORMAL);
 	}
 
 	engine->details->running = FALSE;
@@ -219,8 +221,9 @@ search_provider_error (NautilusSearchProvider *provider,
 }
 
 static void
-search_provider_finished (NautilusSearchProvider *provider,
-			  NautilusSearchEngine   *engine)
+search_provider_finished (NautilusSearchProvider       *provider,
+                          NautilusSearchProviderStatus  status,
+                          NautilusSearchEngine         *engine)
 
 {
 	DEBUG ("Search provider finished");
diff --git a/libnautilus-private/nautilus-search-provider.c b/libnautilus-private/nautilus-search-provider.c
index a1c580952..10aca2020 100644
--- a/libnautilus-private/nautilus-search-provider.c
+++ b/libnautilus-private/nautilus-search-provider.c
@@ -19,6 +19,7 @@
 
 #include <config.h>
 #include "nautilus-search-provider.h"
+#include "nautilus-private-enum-types.c"
 
 #include <glib-object.h>
 
@@ -85,8 +86,9 @@ nautilus_search_provider_base_init (gpointer g_iface)
 					  G_SIGNAL_RUN_LAST,
 					  G_STRUCT_OFFSET (NautilusSearchProviderIface, finished),
 					  NULL, NULL,
-					  g_cclosure_marshal_VOID__VOID,
-					  G_TYPE_NONE, 0);
+					  g_cclosure_marshal_VOID__ENUM,
+					  G_TYPE_NONE, 1,
+                                          NAUTILUS_TYPE_SEARCH_PROVIDER_STATUS);
 
 	signals[ERROR] = g_signal_new ("error",
 				       NAUTILUS_TYPE_SEARCH_PROVIDER,
@@ -137,11 +139,12 @@ nautilus_search_provider_hits_added (NautilusSearchProvider *provider, GList *hi
 }
 
 void
-nautilus_search_provider_finished (NautilusSearchProvider *provider)
+nautilus_search_provider_finished (NautilusSearchProvider       *provider,
+                                   NautilusSearchProviderStatus  status)
 {
 	g_return_if_fail (NAUTILUS_IS_SEARCH_PROVIDER (provider));
 
-	g_signal_emit (provider, signals[FINISHED], 0);
+	g_signal_emit (provider, signals[FINISHED], 0, status);
 }
 
 void
diff --git a/libnautilus-private/nautilus-search-provider.h b/libnautilus-private/nautilus-search-provider.h
index 38ee68751..b3be651b4 100644
--- a/libnautilus-private/nautilus-search-provider.h
+++ b/libnautilus-private/nautilus-search-provider.h
@@ -24,6 +24,11 @@
 
 G_BEGIN_DECLS
 
+typedef enum {
+  NAUTILUS_SEARCH_PROVIDER_STATUS_NORMAL,
+  NAUTILUS_SEARCH_PROVIDER_STATUS_RESTARTING
+} NautilusSearchProviderStatus;
+
 #define NAUTILUS_TYPE_SEARCH_PROVIDER           (nautilus_search_provider_get_type ())
 #define NAUTILUS_SEARCH_PROVIDER(obj)           (G_TYPE_CHECK_INSTANCE_CAST ((obj), NAUTILUS_TYPE_SEARCH_PROVIDER, NautilusSearchProvider))
 #define NAUTILUS_IS_SEARCH_PROVIDER(obj)        (G_TYPE_CHECK_INSTANCE_TYPE ((obj), NAUTILUS_TYPE_SEARCH_PROVIDER))
@@ -42,7 +47,33 @@ struct _NautilusSearchProviderIface {
 
         /* Signals */
         void (*hits_added) (NautilusSearchProvider *provider, GList *hits);
-        void (*finished) (NautilusSearchProvider *provider);
+        /* This signal has a status parameter because it's necesary to discern
+         * when the search engine finished normally or wheter it finished in a
+         * different situation that will cause the engine to do some action after
+         * finishing.
+         *
+         * For example, the search engine restarts itself if the client starts a
+         * new search before all the search providers finished its current ongoing search.
+         *
+         * A real use case of this is when the user change quickly the query of the search,
+         * the search engine stops all the search providers, but given that each search
+         * provider has its own thread it will be actually stopped in a unknown time.
+         * To fix that, the search engine marks itself for restarting if the client
+         * starts a new search and not all providers finished. Then it will emit
+         * its finished signal and restart all providers with the new search.
+         *
+         * That can cause that when the search engine emits its finished signal,
+         * it actually relates to old searchs that it stopped and not the one
+         * the client started lately.
+         * The client doesn't have a way to know wheter the finished signal
+         * relates to its current search or with an old search.
+         *
+         * To fix this situation, provide with the signal a status parameter, that
+         * provides a hint of how the search engine stopped or if it is going to realize
+         * some action afterwards, like restarting.
+         */
+        void (*finished) (NautilusSearchProvider       *provider,
+                          NautilusSearchProviderStatus  status);
         void (*error) (NautilusSearchProvider *provider, const char *error_message);
 };
 
@@ -56,7 +87,8 @@ void           nautilus_search_provider_stop            (NautilusSearchProvider
 
 void           nautilus_search_provider_hits_added      (NautilusSearchProvider *provider,
                                                          GList *hits);
-void           nautilus_search_provider_finished        (NautilusSearchProvider *provider);
+void           nautilus_search_provider_finished        (NautilusSearchProvider       *provider,
+                                                         NautilusSearchProviderStatus  status);
 void           nautilus_search_provider_error           (NautilusSearchProvider *provider,
                                                          const char *error_message);