[evolution/wip/webkit2] Use own thread pool for WebKit content download

[Milan Crha <mcrha src gnome org>]

commit a704671e49dd9b12dd6f28341d9da5e8dcca3b37
Author: Milan Crha <mcrha redhat com>
Date:   Fri Apr 3 08:22:10 2015 +0200

    Use own thread pool for WebKit content download
    
    Mails with many images (remote content in general) could block GTask's
    thread pool for a long time, making starve other requests. Adding our
    own thread pool avoids such job starving.

 e-util/e-misc-utils.c |   74 +++++++++++++++++++++++++++++++++++++++++++++++++
 e-util/e-misc-utils.h |    4 ++
 mail/e-http-request.c |    4 +-
 mail/e-mail-request.c |    4 +-
 4 files changed, 82 insertions(+), 4 deletions(-)
---
diff --git a/e-util/e-misc-utils.c b/e-util/e-misc-utils.c
index ff53bbc..9da55f3 100644
--- a/e-util/e-misc-utils.c
+++ b/e-util/e-misc-utils.c
@@ -3179,3 +3179,77 @@ e_util_prompt_user (GtkWindow *parent,
 
        return button == GTK_RESPONSE_YES;
 }
+
+typedef struct _EUtilSimpleAsyncResultThreadData {
+       GSimpleAsyncResult *simple;
+       GSimpleAsyncThreadFunc func;
+       GCancellable *cancellable;
+} EUtilSimpleAsyncResultThreadData;
+
+static void
+e_util_simple_async_result_thread (gpointer data,
+                                  gpointer user_data)
+{
+       EUtilSimpleAsyncResultThreadData *thread_data = data;
+       GError *error = NULL;
+
+       g_return_if_fail (thread_data != NULL);
+       g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (thread_data->simple));
+       g_return_if_fail (thread_data->func != NULL);
+
+       if (g_cancellable_set_error_if_cancelled (thread_data->cancellable, &error)) {
+               g_simple_async_result_take_error (thread_data->simple, error);
+       } else {
+               thread_data->func (thread_data->simple,
+                       g_async_result_get_source_object (G_ASYNC_RESULT (thread_data->simple)),
+                       thread_data->cancellable);
+       }
+
+       g_simple_async_result_complete_in_idle (thread_data->simple);
+
+       g_clear_object (&thread_data->simple);
+       g_clear_object (&thread_data->cancellable);
+       g_free (thread_data);
+}
+
+/**
+ * e_util_run_simple_async_result_in_thread:
+ * @simple: a #GSimpleAsyncResult
+ * @func: a #GSimpleAsyncThreadFunc to execute in the thread
+ * @cancellable: an optional #GCancellable, or %NULL
+ *
+ * Similar to g_simple_async_result_run_in_thread(), except
+ * it doesn't use GTask internally, thus doesn't block the GTask
+ * thread pool with possibly long job.
+ *
+ * It doesn't behave exactly the same as the g_simple_async_result_run_in_thread(),
+ * the @cancellable checking is not done before the finish.
+ *
+ * Since: 3.18
+ **/
+void
+e_util_run_simple_async_result_in_thread (GSimpleAsyncResult *simple,
+                                         GSimpleAsyncThreadFunc func,
+                                         GCancellable *cancellable)
+{
+       static GThreadPool *thread_pool = NULL;
+       static GMutex thread_pool_mutex;
+       EUtilSimpleAsyncResultThreadData *thread_data;
+
+       g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
+       g_return_if_fail (func != NULL);
+
+       g_mutex_lock (&thread_pool_mutex);
+
+       if (!thread_pool)
+               thread_pool = g_thread_pool_new (e_util_simple_async_result_thread, NULL, 20, FALSE, NULL);
+
+       thread_data = g_new0 (EUtilSimpleAsyncResultThreadData, 1);
+       thread_data->simple = g_object_ref (simple);
+       thread_data->func = func;
+       thread_data->cancellable = cancellable ? g_object_ref (cancellable) : NULL;
+
+       g_thread_pool_push (thread_pool, thread_data, NULL);
+
+       g_mutex_unlock (&thread_pool_mutex);
+}
diff --git a/e-util/e-misc-utils.h b/e-util/e-misc-utils.h
index b7ef19d..b4d9faa 100644
--- a/e-util/e-misc-utils.h
+++ b/e-util/e-misc-utils.h
@@ -277,6 +277,10 @@ gboolean   e_util_prompt_user              (GtkWindow *parent,
                                                 const gchar *promptkey,
                                                 const gchar *tag,
                                                 ...);
+void           e_util_run_simple_async_result_in_thread
+                                               (GSimpleAsyncResult *simple,
+                                                GSimpleAsyncThreadFunc func,
+                                                GCancellable *cancellable);
 
 guint          e_util_normalize_font_size      (GtkWidget *widget,
                                                 gdouble font_size);
diff --git a/mail/e-http-request.c b/mail/e-http-request.c
index 97cd9c9..f59d26c 100644
--- a/mail/e-http-request.c
+++ b/mail/e-http-request.c
@@ -522,9 +522,9 @@ http_request_send_async (SoupRequest *request,
 
        g_simple_async_result_set_check_cancellable (simple, cancellable);
 
-       g_simple_async_result_run_in_thread (
+       e_util_run_simple_async_result_in_thread (
                simple, handle_http_request,
-               G_PRIORITY_DEFAULT, cancellable);
+               cancellable);
 
        g_object_unref (simple);
 }
diff --git a/mail/e-mail-request.c b/mail/e-mail-request.c
index f11b3be..9a97f4f 100644
--- a/mail/e-mail-request.c
+++ b/mail/e-mail-request.c
@@ -362,9 +362,9 @@ mail_request_send_async (SoupRequest *request,
        g_simple_async_result_set_check_cancellable (simple, cancellable);
 
        if (g_strcmp0 (uri->host, "contact-photo") == 0) {
-               g_simple_async_result_run_in_thread (
+               e_util_run_simple_async_result_in_thread (
                        simple, handle_contact_photo_request,
-                       G_PRIORITY_DEFAULT, cancellable);
+                       cancellable);
        } else {
                /* Process e-mail mail requests in this thread, which should be
                 * the main/UI thread, because any EMailFormatter can create