Submit MLS requests with combined WiFi and 3GPP tower data

Currently, there is no combining of WiFi Access Points data and 3GPP tower
data to make a single, combined MLS geolocation request.
Instead, the code does two separate MLS requests if both of these sources
are available, each containing only either WiFi AP data or 3GPP tower data.

This results in two different location determinations.
If these two locations differ (which happens often) the Geoclue location
jumps between these two locations as WiFi and 3GPP location sources are
refreshed.

There is also a problem of reduced accuracy since with two separate
requests the MLS backend can't cross-correlate data between both.

Instead, one is supposed to send a MLS query containing all the collected
data at the same time, like the example at MLS API page shows.
The same goes for MLS location submissions.

Sending WiFi and 3GPP tower data combined makes Geoclue location
determination significantly more stable indeed when both of these sources
are active.

1 files changed, 90 insertions, 28 deletions

diff --git a/src/gclue-wifi.c b/src/gclue-wifi.c
index 1c309eb..5d3685b 100644
--- a/src/gclue-wifi.c
+++ b/src/gclue-wifi.c
@@ -24,6 +24,7 @@
 #include <string.h>
 #include <config.h>
 #include "gclue-wifi.h"
+#include "gclue-3g.h"
 #include "gclue-config.h"
 #include "gclue-error.h"
 #include "gclue-mozilla.h"
@@ -134,6 +135,7 @@ static void location_cache_value_free (gpointer data)
 }
 
 struct _GClueWifiPrivate {
+        GClueMozilla *mozilla;
         WPASupplicant *supplicant;
         WPAInterface *interface;
         GHashTable *bss_proxies;
@@ -203,6 +205,7 @@ gclue_wifi_finalize (GObject *gwifi)
         g_clear_pointer (&wifi->priv->bss_proxies, g_hash_table_unref);
         g_clear_pointer (&wifi->priv->ignored_bss_proxies, g_hash_table_unref);
         g_clear_pointer (&wifi->priv->location_cache, g_hash_table_unref);
+        g_clear_object (&wifi->priv->mozilla);
 }
 
 static void
@@ -499,6 +502,11 @@ on_scan_timeout (gpointer user_data)
         return G_SOURCE_REMOVE;
 }
 
+gboolean gclue_wifi_should_skip_bsss (GClueAccuracyLevel level)
+{
+        return level < GCLUE_ACCURACY_LEVEL_STREET;
+}
+
 static gboolean
 on_scan_wait_done (gpointer wifi)
 {
@@ -507,9 +515,13 @@ on_scan_wait_done (gpointer wifi)
         g_return_val_if_fail (GCLUE_IS_WIFI (wifi), G_SOURCE_REMOVE);
         priv = GCLUE_WIFI(wifi)->priv;
 
+        /* We have the latest scan result */
+        gclue_mozilla_set_wifi (priv->mozilla, wifi);
+
         if (priv->bss_list_changed) {
                 priv->bss_list_changed = FALSE;
                 g_debug ("Refreshing location…");
+                gclue_mozilla_set_bss_dirty (priv->mozilla);
                 gclue_web_source_refresh (GCLUE_WEB_SOURCE (wifi));
         }
         priv->scan_wait_id = 0;
@@ -811,6 +823,8 @@ gclue_wifi_start (GClueLocationSource *source)
 static GClueLocationSourceStopResult
 gclue_wifi_stop (GClueLocationSource *source)
 {
+        GClueWifi *wifi = GCLUE_WIFI (source);
+        GClueWifiPrivate *priv = wifi->priv;
         GClueLocationSourceClass *base_class;
         GClueLocationSourceStopResult base_result;
 
@@ -824,6 +838,10 @@ gclue_wifi_stop (GClueLocationSource *source)
         disconnect_bss_signals (GCLUE_WIFI (source));
         disconnect_cache_prune_timeout (GCLUE_WIFI (source));
 
+        if (gclue_mozilla_test_set_wifi (priv->mozilla, wifi, NULL)) {
+                g_debug ("Removed us as the WiFi source on stop");
+        }
+
         return base_result;
 }
 
@@ -836,11 +854,10 @@ gclue_wifi_get_available_accuracy_level (GClueWebSource *source,
 
         if (!net_available)
                 return GCLUE_ACCURACY_LEVEL_NONE;
-        else if (priv->interface != NULL &&
-                 get_accuracy_level (wifi) != GCLUE_ACCURACY_LEVEL_CITY)
-                return GCLUE_ACCURACY_LEVEL_STREET;
-        else
+        else if (!priv->interface)
                 return GCLUE_ACCURACY_LEVEL_CITY;
+        else
+                return MIN (get_accuracy_level (wifi), GCLUE_ACCURACY_LEVEL_STREET);
 }
 
 static void
@@ -918,6 +935,10 @@ on_interface_removed (WPASupplicant *supplicant,
         disconnect_bss_signals (wifi);
         g_clear_object (&wifi->priv->interface);
 
+        if (gclue_mozilla_test_set_wifi (priv->mozilla, wifi, NULL)) {
+                g_debug ("Removed interface was the WiFi source");
+        }
+
         gclue_web_source_refresh (GCLUE_WEB_SOURCE (wifi));
 }
 
@@ -926,6 +947,7 @@ gclue_wifi_init (GClueWifi *wifi)
 {
         wifi->priv = gclue_wifi_get_instance_private (wifi);
 
+        wifi->priv->mozilla = gclue_mozilla_get_singleton ();
         wifi->priv->bss_proxies = g_hash_table_new_full (g_str_hash,
                                                          g_str_equal,
                                                          g_free,
@@ -1012,23 +1034,29 @@ on_wifi_destroyed (gpointer data,
 GClueWifi *
 gclue_wifi_get_singleton (GClueAccuracyLevel level)
 {
-        static GClueWifi *wifi[] = { NULL, NULL };
+        static GClueWifi *wifi[] = { NULL, NULL, NULL };
         guint i;
+        GClueConfig *config = gclue_config_get_singleton ();
+        gboolean wifi_enabled;
         gboolean scramble_location = FALSE;
         gboolean compute_movement = FALSE;
 
         g_return_val_if_fail (level >= GCLUE_ACCURACY_LEVEL_CITY, NULL);
-        if (level == GCLUE_ACCURACY_LEVEL_NEIGHBORHOOD)
-                level = GCLUE_ACCURACY_LEVEL_CITY;
 
+        wifi_enabled = gclue_config_get_enable_wifi_source (config);
         if (level == GCLUE_ACCURACY_LEVEL_CITY) {
-                GClueConfig *config = gclue_config_get_singleton ();
-
                 i = 0;
-                if (gclue_config_get_enable_wifi_source (config))
+                if (wifi_enabled)
                         scramble_location = TRUE;
-        } else {
+        } else if (level == GCLUE_ACCURACY_LEVEL_NEIGHBORHOOD) {
+                g_return_val_if_fail (wifi_enabled, NULL);
+
                 i = 1;
+                scramble_location = TRUE;
+        } else {
+                g_return_val_if_fail (wifi_enabled, NULL);
+
+                i = 2;
                 compute_movement = TRUE;
         }
 
@@ -1048,8 +1076,8 @@ gclue_wifi_get_singleton (GClueAccuracyLevel level)
 }
 
 /* Can return NULL, signifying an empty BSS list. */
-static GList *
-get_bss_list (GClueWifi *wifi)
+GList *
+gclue_wifi_get_bss_list (GClueWifi *wifi)
 {
         return g_hash_table_get_values (wifi->priv->bss_proxies);
 }
@@ -1059,17 +1087,16 @@ gclue_wifi_create_query (GClueWebSource *source,
                          GError        **error)
 {
         GClueWifi *wifi = GCLUE_WIFI (source);
-        GList *bss_list = NULL; /* As in Access Points */
+        GClueAccuracyLevel level;
+        gboolean skip_tower;
         SoupMessage *msg;
 
         if (wifi->priv->interface == NULL) {
                 goto create_query;
         }
 
-        bss_list = get_bss_list (wifi);
-
         /* Empty list? */
-        if (bss_list == NULL) {
+        if (!g_hash_table_size (wifi->priv->bss_proxies)) {
                 g_set_error_literal (error,
                                      G_IO_ERROR,
                                      G_IO_ERROR_FAILED,
@@ -1078,8 +1105,14 @@ gclue_wifi_create_query (GClueWebSource *source,
         }
 
 create_query:
-        msg = gclue_mozilla_create_query (bss_list, NULL, error);
-        g_list_free (bss_list);
+        level = get_accuracy_level (wifi);
+        skip_tower = gclue_3g_should_skip_tower (level);
+        if (skip_tower) {
+                g_debug ("Will skip 3GPP tower in query as our accuracy level is %d",
+                         (int)level);
+        }
+
+        msg = gclue_mozilla_create_query (wifi->priv->mozilla, skip_tower, FALSE, error);
         return msg;
 }
 
@@ -1097,7 +1130,6 @@ gclue_wifi_create_submit_query (GClueWebSource  *source,
                                 GError         **error)
 {
         GClueWifi *wifi = GCLUE_WIFI (source);
-        GList *bss_list; /* As in Access Points */
         SoupMessage * msg;
 
         if (wifi->priv->interface == NULL) {
@@ -1108,10 +1140,8 @@ gclue_wifi_create_submit_query (GClueWebSource  *source,
                 return NULL;
         }
 
-        bss_list = get_bss_list (wifi);
-
         /* Empty list? */
-        if (bss_list == NULL) {
+        if (!g_hash_table_size (wifi->priv->bss_proxies)) {
                 g_set_error_literal (error,
                                      G_IO_ERROR,
                                      G_IO_ERROR_FAILED,
@@ -1119,11 +1149,9 @@ gclue_wifi_create_submit_query (GClueWebSource  *source,
                 return NULL;
         }
 
-        msg = gclue_mozilla_create_submit_query (location,
-                                                 bss_list,
-                                                 NULL,
+        msg = gclue_mozilla_create_submit_query (wifi->priv->mozilla,
+                                                 location,
                                                  error);
-        g_list_free (bss_list);
         return msg;
 }
 
@@ -1166,6 +1194,36 @@ variant_hash (gconstpointer key)
         return g_bytes_hash (bytes);
 }
 
+static void location_cache_key_fill_tower (GClueWifi *wifi, GClue3GTower *tower)
+{
+        GClueWifiPrivate *priv = wifi->priv;
+        GClue3GTower *moztower;
+        GClueAccuracyLevel level;
+
+        memset (tower, 0, sizeof (*tower));
+        tower->tec = GCLUE_TOWER_TEC_NO_FIX;
+
+        moztower = gclue_mozilla_get_tower (priv->mozilla);
+        level = get_accuracy_level (wifi);
+        if (!moztower || gclue_3g_should_skip_tower (level)) {
+                return;
+        }
+
+        g_assert (moztower->tec != GCLUE_TOWER_TEC_NO_FIX);
+        *tower = *moztower;
+}
+
+static void location_cache_key_add_tower (GClueWifi *wifi, GVariantBuilder *builder)
+{
+        GClue3GTower tower;
+
+        location_cache_key_fill_tower (wifi, &tower);
+        g_variant_builder_add (builder, "u", (guint32)tower.tec);
+        g_variant_builder_add (builder, "s", tower.opc);
+        g_variant_builder_add (builder, "t", (guint64)tower.lac);
+        g_variant_builder_add (builder, "t", (guint64)tower.cell_id);
+}
+
 static GPtrArray *
 get_location_cache_bss_array (GClueWifi *wifi)
 {
@@ -1198,7 +1256,10 @@ get_location_cache_hashtable_key (GClueWifi *wifi, GPtrArray *bss_array)
         GVariantBuilder builder;
 
         /* Serialise to a variant. */
-        g_variant_builder_init (&builder, G_VARIANT_TYPE ("aay"));
+        g_variant_builder_init (&builder, G_VARIANT_TYPE ("(usttaay)"));
+        location_cache_key_add_tower (wifi, &builder);
+
+        g_variant_builder_open (&builder, G_VARIANT_TYPE ("aay"));
         for (i = 0; i < bss_array->len; i++) {
                 WPABSS *bss = WPA_BSS (bss_array->pdata[i]);
                 GVariant *bssid;
@@ -1209,6 +1270,7 @@ get_location_cache_hashtable_key (GClueWifi *wifi, GPtrArray *bss_array)
 
                 g_variant_builder_add_value (&builder, bssid);
         }
+        g_variant_builder_close (&builder);
 
         return g_variant_builder_end (&builder);
 }