[evolution-data-server] Bug #730281 - [CalDAV] Recover after temporary connection lost

[Milan Crha <mcrha src gnome org>]

commit 6b417fa84c0f23a9b4fcbf6de62231f8f4a8aeda
Author: Milan Crha <mcrha redhat com>
Date:   Thu May 22 19:46:50 2014 +0200

    Bug #730281 - [CalDAV] Recover after temporary connection lost

 calendar/backends/caldav/e-cal-backend-caldav.c |   85 +++++++++--------------
 1 files changed, 34 insertions(+), 51 deletions(-)
---
diff --git a/calendar/backends/caldav/e-cal-backend-caldav.c b/calendar/backends/caldav/e-cal-backend-caldav.c
index 962f359..999e76c 100644
--- a/calendar/backends/caldav/e-cal-backend-caldav.c
+++ b/calendar/backends/caldav/e-cal-backend-caldav.c
@@ -150,6 +150,8 @@ G_DEFINE_TYPE_WITH_CODE (
 #define DEBUG_SERVER_ITEMS "items"
 #define DEBUG_ATTACHMENTS "attachments"
 
+static gboolean open_calendar_wrapper (ECalBackendCalDAV *cbdav, GCancellable *cancellable, GError **error, 
gboolean can_call_authenticate, gboolean *know_unreachable);
+
 static void convert_to_inline_attachment (ECalBackendCalDAV *cbdav, icalcomponent *icalcomp);
 static void convert_to_url_attachment (ECalBackendCalDAV *cbdav, icalcomponent *icalcomp);
 static void remove_cached_attachment (ECalBackendCalDAV *cbdav, const gchar *uid);
@@ -2511,8 +2513,12 @@ caldav_synch_slave_loop (gpointer data)
                        /* just sleep until we get woken up again */
                        g_cond_wait (&cbdav->priv->cond, &cbdav->priv->busy_lock);
 
-                       /* check if we should die, work or sleep again */
-                       continue;
+                       /* This means to honor SLAVE_SHOULD_SLEEP only if the backend is opened */
+                       if (cbdav->priv->slave_cmd == SLAVE_SHOULD_DIE ||
+                           cbdav->priv->opened) {
+                               /* check if we should die, work or sleep again */
+                               continue;
+                       }
                }
 
                /* Ok here we go, do some real work
@@ -2525,37 +2531,13 @@ caldav_synch_slave_loop (gpointer data)
                }
 
                if (!cbdav->priv->opened) {
-                       gboolean server_unreachable = FALSE;
-                       GError *local_error = NULL;
-
-                       if (caldav_server_open_calendar (cbdav, &server_unreachable, NULL, &local_error)) {
+                       if (open_calendar_wrapper (cbdav, NULL, NULL, TRUE, &know_unreachable)) {
                                cbdav->priv->opened = TRUE;
                                update_slave_cmd (cbdav->priv, SLAVE_SHOULD_WORK);
                                g_cond_signal (&cbdav->priv->cond);
 
                                cbdav->priv->is_google = is_google_uri (cbdav->priv->uri);
                                know_unreachable = FALSE;
-                       } else if (local_error) {
-                               cbdav->priv->opened = FALSE;
-                               e_cal_backend_set_writable (
-                                       E_CAL_BACKEND (cbdav), FALSE);
-
-                               if (!know_unreachable) {
-                                       gchar *msg;
-
-                                       know_unreachable = TRUE;
-
-                                       msg = g_strdup_printf (_("Server is unreachable, calendar is opened 
in read-only mode.\nError message: %s"), local_error->message);
-                                       e_cal_backend_notify_error (E_CAL_BACKEND (cbdav), msg);
-                                       g_free (msg);
-                               }
-
-                               g_clear_error (&local_error);
-                       } else {
-                               cbdav->priv->opened = FALSE;
-                               e_cal_backend_set_writable (
-                                       E_CAL_BACKEND (cbdav), FALSE);
-                               know_unreachable = TRUE;
                        }
                }
 
@@ -2888,9 +2870,11 @@ initialize_backend (ECalBackendCalDAV *cbdav,
 }
 
 static gboolean
-open_calendar (ECalBackendCalDAV *cbdav,
-               GCancellable *cancellable,
-               GError **error)
+open_calendar_wrapper (ECalBackendCalDAV *cbdav,
+                      GCancellable *cancellable,
+                      GError **error,
+                      gboolean can_call_authenticate,
+                      gboolean *know_unreachable)
 {
        gboolean server_unreachable = FALSE;
        gboolean success;
@@ -2898,8 +2882,12 @@ open_calendar (ECalBackendCalDAV *cbdav,
 
        g_return_val_if_fail (cbdav != NULL, FALSE);
 
-       success = caldav_server_open_calendar (
-               cbdav, &server_unreachable, cancellable, &local_error);
+       success = caldav_server_open_calendar (cbdav, &server_unreachable, cancellable, &local_error);
+
+       if (can_call_authenticate && g_error_matches (local_error, E_DATA_CAL_ERROR, AuthenticationFailed)) {
+               g_clear_error (&local_error);
+               success = caldav_authenticate (cbdav, FALSE, cancellable, &local_error);
+       }
 
        if (success) {
                update_slave_cmd (cbdav->priv, SLAVE_SHOULD_WORK);
@@ -2910,11 +2898,18 @@ open_calendar (ECalBackendCalDAV *cbdav,
                cbdav->priv->opened = FALSE;
                e_cal_backend_set_writable (E_CAL_BACKEND (cbdav), FALSE);
                if (local_error) {
-                       gchar *msg = g_strdup_printf (_("Server is unreachable, calendar is opened in 
read-only mode.\nError message: %s"), local_error->message);
-                       e_cal_backend_notify_error (E_CAL_BACKEND (cbdav), msg);
-                       g_free (msg);
-                       g_clear_error (&local_error);
-                       success = TRUE;
+                       if (know_unreachable && !*know_unreachable) {
+                               gchar *msg = g_strdup_printf (_("Server is unreachable, calendar is opened in 
read-only mode.\nError message: %s"), local_error->message);
+                               e_cal_backend_notify_error (E_CAL_BACKEND (cbdav), msg);
+                               g_free (msg);
+                               g_clear_error (&local_error);
+
+                               *know_unreachable = TRUE;
+                       } else {
+                               /* this allows to open the calendar in read-only mode */
+                               g_clear_error (&local_error);
+                               success = TRUE;
+                       }
                }
        }
 
@@ -2959,19 +2954,7 @@ caldav_do_open (ECalBackendSync *backend,
        cbdav->priv->is_google = FALSE;
 
        if (online) {
-               GError *local_error = NULL;
-
-               open_calendar (cbdav, cancellable, &local_error);
-
-               if (g_error_matches (local_error, E_DATA_CAL_ERROR, AuthenticationFailed)) {
-                       g_clear_error (&local_error);
-                       caldav_authenticate (
-                               cbdav, FALSE, cancellable, perror);
-               }
-
-               if (local_error != NULL)
-                       g_propagate_error (perror, local_error);
-
+               open_calendar_wrapper (cbdav, cancellable, perror, TRUE, NULL);
        } else {
                e_cal_backend_set_writable (E_CAL_BACKEND (cbdav), FALSE);
        }
@@ -5163,7 +5146,7 @@ caldav_try_password_sync (ESourceAuthenticator *authenticator,
        g_free (cbdav->priv->password);
        cbdav->priv->password = g_strdup (password->str);
 
-       open_calendar (cbdav, cancellable, &local_error);
+       open_calendar_wrapper (cbdav, cancellable, &local_error, FALSE, NULL);
 
        if (local_error == NULL) {
                result = E_SOURCE_AUTHENTICATION_ACCEPTED;