[evolution/evolution-3-12] Bug 740297 - [SMTP] Crash when sending two messages at once

[Milan Crha <mcrha src gnome org>]

commit f2a6072d31c1782540e26429a22523437cdb288b
Author: Milan Crha <mcrha redhat com>
Date:   Wed Dec 10 10:26:38 2014 +0100

    Bug 740297 - [SMTP] Crash when sending two messages at once

 libemail-engine/e-mail-session-utils.c |   12 ++++-
 libemail-engine/e-mail-session.c       |   94 ++++++++++++++++++++++++++++++++
 libemail-engine/e-mail-session.h       |    7 +++
 libemail-engine/mail-ops.c             |   21 +++++--
 4 files changed, 126 insertions(+), 8 deletions(-)
---
diff --git a/libemail-engine/e-mail-session-utils.c b/libemail-engine/e-mail-session-utils.c
index a248eac..295fe24 100644
--- a/libemail-engine/e-mail-session-utils.c
+++ b/libemail-engine/e-mail-session-utils.c
@@ -540,14 +540,20 @@ mail_session_send_to_thread (GSimpleAsyncResult *simple,
                return;
        }
 
+       if (!e_mail_session_mark_service_used_sync (session, context->transport, cancellable)) {
+               g_warn_if_fail (g_cancellable_set_error_if_cancelled (cancellable, &error));
+               g_simple_async_result_take_error (simple, error);
+               return;
+       }
+
        status = camel_service_get_connection_status (context->transport);
        if (status != CAMEL_SERVICE_CONNECTED) {
                did_connect = TRUE;
 
-               camel_service_connect_sync (
-                       context->transport, cancellable, &error);
+               camel_service_connect_sync (context->transport, cancellable, &error);
 
                if (error != NULL) {
+                       e_mail_session_unmark_service_used (session, context->transport);
                        g_simple_async_result_take_error (simple, error);
                        return;
                }
@@ -579,6 +585,8 @@ mail_session_send_to_thread (GSimpleAsyncResult *simple,
                }
        }
 
+       e_mail_session_unmark_service_used (session, context->transport);
+
        if (error != NULL) {
                g_simple_async_result_take_error (simple, error);
                return;
diff --git a/libemail-engine/e-mail-session.c b/libemail-engine/e-mail-session.c
index 5578a78..f54025e 100644
--- a/libemail-engine/e-mail-session.c
+++ b/libemail-engine/e-mail-session.c
@@ -91,6 +91,10 @@ struct _EMailSessionPrivate {
 
        guint preparing_flush;
        GMutex preparing_flush_lock;
+
+       GMutex used_services_lock;
+       GCond used_services_cond;
+       GHashTable *used_services;
 };
 
 struct _AsyncContext {
@@ -956,11 +960,14 @@ mail_session_finalize (GObject *object)
 
        g_hash_table_destroy (priv->auto_refresh_table);
        g_hash_table_destroy (priv->junk_filters);
+       g_hash_table_destroy (priv->used_services);
 
        g_ptr_array_free (priv->local_folders, TRUE);
        g_ptr_array_free (priv->local_folder_uris, TRUE);
 
        g_mutex_clear (&priv->preparing_flush_lock);
+       g_mutex_clear (&priv->used_services_lock);
+       g_cond_clear (&priv->used_services_cond);
 
        g_free (mail_data_dir);
        g_free (mail_config_dir);
@@ -1799,6 +1806,10 @@ e_mail_session_init (EMailSession *session)
                (GDestroyNotify) g_free);
 
        g_mutex_init (&session->priv->preparing_flush_lock);
+       g_mutex_init (&session->priv->used_services_lock);
+       g_cond_init (&session->priv->used_services_cond);
+
+       session->priv->used_services = g_hash_table_new (g_direct_hash, g_direct_equal);
 }
 
 EMailSession *
@@ -2367,3 +2378,86 @@ e_mail_session_create_vfolder_context (EMailSession *session)
        return class->create_vfolder_context (session);
 }
 
+static void
+mail_session_wakeup_used_services_cond (GCancellable *cancenllable,
+                                         EMailSession *session)
+{
+       g_return_if_fail (E_IS_MAIL_SESSION (session));
+
+       /* Use broadcast here, because it's not known which operation had been
+          cancelled, thus rather wake up all of them to retest. */
+       g_cond_broadcast (&session->priv->used_services_cond);
+}
+
+/**
+ * e_mail_session_mark_service_used_sync:
+ * @session: an #EMailSession
+ * @service: a #CamelService
+ * @cancellable: (allow none): a #GCancellable, or NULL
+ *
+ * Marks the @service as being used. If it is already in use, then waits
+ * for its release. The only reasons for a failure are either invalid
+ * parameters being passed in the function or the wait being cancelled.
+ * Use e_mail_session_unmark_service_used() to notice the @session that
+ * that the @service is no longer being used by the caller.
+ *
+ * Returns: Whether successfully waited for the @service.
+ *
+ * Since: 3.12.10
+ **/
+gboolean
+e_mail_session_mark_service_used_sync (EMailSession *session,
+                                      CamelService *service,
+                                      GCancellable *cancellable)
+{
+       gulong cancelled_id = 0;
+
+       g_return_val_if_fail (E_IS_MAIL_SESSION (session), FALSE);
+       g_return_val_if_fail (CAMEL_IS_SERVICE (service), FALSE);
+
+       g_mutex_lock (&session->priv->used_services_lock);
+
+       if (cancellable)
+               cancelled_id = g_cancellable_connect (cancellable, G_CALLBACK 
(mail_session_wakeup_used_services_cond), session, NULL);
+
+       while (!g_cancellable_is_cancelled (cancellable) &&
+               g_hash_table_contains (session->priv->used_services, service)) {
+               g_cond_wait (&session->priv->used_services_cond, &session->priv->used_services_lock);
+       }
+
+       if (cancelled_id)
+               g_cancellable_disconnect (cancellable, cancelled_id);
+
+       if (!g_cancellable_is_cancelled (cancellable))
+               g_hash_table_insert (session->priv->used_services, service, GINT_TO_POINTER (1));
+
+       g_mutex_unlock (&session->priv->used_services_lock);
+
+       return !g_cancellable_is_cancelled (cancellable);
+}
+
+/**
+ * e_mail_session_unmark_service_used:
+ * @session: an #EMailSession
+ * @service: a #CamelService
+ *
+ * Frees a "use lock" on the @service, thus it can be used by others. If anything
+ * is waiting for it in e_mail_session_mark_service_used_sync(), then it is woken up.
+ *
+ * Since: 3.12.10
+ **/
+void
+e_mail_session_unmark_service_used (EMailSession *session,
+                                   CamelService *service)
+{
+       g_return_if_fail (E_IS_MAIL_SESSION (session));
+       g_return_if_fail (CAMEL_IS_SERVICE (service));
+
+       g_mutex_lock (&session->priv->used_services_lock);
+
+       if (g_hash_table_remove (session->priv->used_services, service)) {
+               g_cond_signal (&session->priv->used_services_cond);
+       }
+
+       g_mutex_unlock (&session->priv->used_services_lock);
+}
diff --git a/libemail-engine/e-mail-session.h b/libemail-engine/e-mail-session.h
index 7959d0c..674858d 100644
--- a/libemail-engine/e-mail-session.h
+++ b/libemail-engine/e-mail-session.h
@@ -150,6 +150,13 @@ CamelFolder *      e_mail_session_uri_to_folder_finish
 EMVFolderContext *
                e_mail_session_create_vfolder_context
                                                (EMailSession *session);
+gboolean       e_mail_session_mark_service_used_sync
+                                               (EMailSession *session,
+                                                CamelService *service,
+                                                GCancellable *cancellable);
+void           e_mail_session_unmark_service_used
+                                               (EMailSession *session,
+                                                CamelService *service);
 
 /* Useful GBinding transform functions */
 gboolean       e_binding_transform_service_to_source
diff --git a/libemail-engine/mail-ops.c b/libemail-engine/mail-ops.c
index 969fbcb..e84a412 100644
--- a/libemail-engine/mail-ops.c
+++ b/libemail-engine/mail-ops.c
@@ -590,7 +590,6 @@ static void
 mail_send_message (struct _send_queue_msg *m,
                    CamelFolder *queue,
                    const gchar *uid,
-                   CamelTransport *transport,
                    CamelFilterDriver *driver,
                    GCancellable *cancellable,
                    GError **error)
@@ -622,17 +621,24 @@ mail_send_message (struct _send_queue_msg *m,
        if (service != NULL)
                provider = camel_service_get_provider (service);
 
-       err = g_string_new ("");
-       xev = mail_tool_remove_xevolution_headers (message);
-
        if (CAMEL_IS_TRANSPORT (service)) {
                const gchar *tuid;
 
                /* Let the dialog know the right account it is using. */
-               tuid = camel_service_get_uid (CAMEL_SERVICE (transport));
+               tuid = camel_service_get_uid (service);
                report_status (m, CAMEL_FILTER_STATUS_ACTION, 0, tuid);
        }
 
+       if (service && !e_mail_session_mark_service_used_sync (m->session, service, cancellable)) {
+               g_warn_if_fail (g_cancellable_set_error_if_cancelled (cancellable, error));
+               g_clear_object (&service);
+               g_clear_object (&message);
+               return;
+       }
+
+       err = g_string_new ("");
+       xev = mail_tool_remove_xevolution_headers (message);
+
        /* Check for email sending */
        from = (CamelAddress *) camel_internet_address_new ();
        resent_from = camel_medium_get_header (
@@ -857,6 +863,9 @@ exit:
                }
        }
 
+       if (service)
+               e_mail_session_unmark_service_used (m->session, service);
+
        if (local_error != NULL)
                g_propagate_error (error, local_error);
 
@@ -957,7 +966,7 @@ send_queue_exec (struct _send_queue_msg *m,
                        cancellable, (i + 1) * 100 / send_uids->len);
 
                mail_send_message (
-                       m, m->queue, send_uids->pdata[i], m->transport,
+                       m, m->queue, send_uids->pdata[i],
                        m->driver, cancellable, &local_error);
                if (local_error != NULL) {
                        if (!g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_CANCELLED)) {