core: cleanup nm_config_device_state_prune_unseen() and accept NMPlatform for skipping pruning

src/nm-config.c

@@ -2299,6 +2299,8 @@ _config_device_state_data_new (int ifindex, GKeyFile *kf)
 	return device_state;
 }
 
+#define DEVICE_STATE_FILENAME_LEN_MAX 60
+
 /**
  * nm_config_device_state_load:
  * @ifindex: the ifindex for which the state is to load
@@ -2310,7 +2312,7 @@ NMConfigDeviceStateData *
 nm_config_device_state_load (int ifindex)
 {
 	NMConfigDeviceStateData *device_state;
-	char path[NM_STRLEN (NM_CONFIG_DEVICE_STATE_DIR) + 60];
+	char path[NM_STRLEN (NM_CONFIG_DEVICE_STATE_DIR"/") + DEVICE_STATE_FILENAME_LEN_MAX + 1];
 	gs_unref_keyfile GKeyFile *kf = NULL;
 	const char *nm_owned_str;
 
@@ -2394,7 +2396,7 @@ nm_config_device_state_write (int ifindex,
                               const char *next_server,
                               const char *root_path)
 {
-	char path[NM_STRLEN (NM_CONFIG_DEVICE_STATE_DIR) + 60];
+	char path[NM_STRLEN (NM_CONFIG_DEVICE_STATE_DIR"/") + DEVICE_STATE_FILENAME_LEN_MAX + 1];
 	GError *local = NULL;
 	gs_unref_keyfile GKeyFile *kf = NULL;
 
@@ -2477,35 +2479,43 @@ nm_config_device_state_write (int ifindex,
 }
 
 void
-nm_config_device_state_prune_unseen (GHashTable *seen_ifindexes)
+nm_config_device_state_prune_unseen (GHashTable *preserve_ifindexes,
+                                     NMPlatform *preserve_in_platform)
 {
 	GDir *dir;
 	const char *fn;
-	int ifindex;
-	gsize fn_len;
-	char buf[NM_STRLEN (NM_CONFIG_DEVICE_STATE_DIR"/") + 30 + 3] = NM_CONFIG_DEVICE_STATE_DIR"/";
+	char buf[NM_STRLEN (NM_CONFIG_DEVICE_STATE_DIR"/") + DEVICE_STATE_FILENAME_LEN_MAX + 1] = NM_CONFIG_DEVICE_STATE_DIR"/";
 	char *buf_p = &buf[NM_STRLEN (NM_CONFIG_DEVICE_STATE_DIR"/")];
 
-	g_return_if_fail (seen_ifindexes);
-
 	dir = g_dir_open (NM_CONFIG_DEVICE_STATE_DIR, 0, NULL);
 	if (!dir)
 		return;
 
 	while ((fn = g_dir_read_name (dir))) {
+		int ifindex;
+		gsize fn_len;
+
 		ifindex = _device_state_parse_filename (fn);
 		if (ifindex <= 0)
 			continue;
-		if (g_hash_table_contains (seen_ifindexes, GINT_TO_POINTER (ifindex)))
+
+		if (   preserve_ifindexes
+		    && g_hash_table_contains (preserve_ifindexes, GINT_TO_POINTER (ifindex)))
 			continue;
 
-		fn_len = strlen (fn) + 1;
+		if (   preserve_in_platform
+		    && nm_platform_link_get (preserve_in_platform, ifindex))
+			continue;
+
+		fn_len = strlen (fn);
+		nm_assert (fn_len > 0);
 		nm_assert (&buf_p[fn_len] < &buf[G_N_ELEMENTS (buf)]);
-		memcpy (buf_p, fn, fn_len);
+		memcpy (buf_p, fn, fn_len + 1u);
 		nm_assert (({
 		                char bb[30];
-		                nm_sprintf_buf (bb, "%d", ifindex);
-		                nm_streq0 (bb, buf_p);
+
+		                nm_streq0 (nm_sprintf_buf (bb, "%d", ifindex),
+		                           buf_p);
 		           }));
 		_LOGT ("device-state: prune #%d (%s)", ifindex, buf);
 		(void) unlink (buf);

src/nm-config.h

@@ -258,7 +258,8 @@ gboolean nm_config_device_state_write (int ifindex,
                                        const char *next_server,
                                        const char *root_path);
 
-void nm_config_device_state_prune_unseen (GHashTable *seen_ifindexes);
+void nm_config_device_state_prune_unseen (GHashTable *preserve_ifindexes,
+                                          NMPlatform *preserve_in_platform);
 
 const GHashTable *nm_config_device_state_get_all (NMConfig *self);
 const NMConfigDeviceStateData *nm_config_device_state_get (NMConfig *self,

src/nm-manager.c

@@ -6555,19 +6555,19 @@ void
 nm_manager_write_device_state_all (NMManager *self)
 {
 	NMManagerPrivate *priv = NM_MANAGER_GET_PRIVATE (self);
-	gs_unref_hashtable GHashTable *seen_ifindexes = NULL;
+	gs_unref_hashtable GHashTable *preserve_ifindexes = NULL;
 	NMDevice *device;
 
-	seen_ifindexes = g_hash_table_new (nm_direct_hash, NULL);
+	preserve_ifindexes = g_hash_table_new (nm_direct_hash, NULL);
 
 	c_list_for_each_entry (device, &priv->devices_lst_head, devices_lst) {
 		if (nm_manager_write_device_state (self, device)) {
-			g_hash_table_add (seen_ifindexes,
+			g_hash_table_add (preserve_ifindexes,
 			                  GINT_TO_POINTER (nm_device_get_ip_ifindex (device)));
 		}
 	}
 
-	nm_config_device_state_prune_unseen (seen_ifindexes);
+	nm_config_device_state_prune_unseen (preserve_ifindexes, NULL);
 }
 
 static gboolean