libview: make sure gtk_print_operation_cancel() is called from draw-page callback

Fixes crash when printing operation is cancelled.

Taken from evince commit: a09aa79195825d5d9c80c36362203c7c36a5e914
From: Carlos Garcia Campos <[email protected]>
Gnome bug: https://bugzilla.gnome.org/show_bug.cgi?id=635619

1 files changed, 33 insertions, 7 deletions

diff --git a/libview/ev-print-operation.c b/libview/ev-print-operation.c
index 3cec253a..6b972f4e 100644
--- a/libview/ev-print-operation.c
+++ b/libview/ev-print-operation.c
@@ -1628,7 +1628,10 @@ ev_print_operation_print_cancel (EvPrintOperation *op)
 {
 	EvPrintOperationPrint *print = EV_PRINT_OPERATION_PRINT (op);
 
-	gtk_print_operation_cancel (print->op);
+        if (print->job_print)
+                ev_job_cancel (print->job_print);
+        else
+                gtk_print_operation_cancel (print->op);
 }
 
 static void
@@ -1707,11 +1710,30 @@ print_job_finished (EvJobPrint            *job,
 	ev_job_print_set_cairo (job, NULL);
 }
 
+static gboolean
+draw_page_finish_idle (EvPrintOperationPrint *print)
+{
+        if (ev_job_scheduler_get_running_thread_job () == print->job_print)
+                return TRUE;
+
+        gtk_print_operation_draw_page_finish (print->op);
+
+        return FALSE;
+}
+
 static void
 print_job_cancelled (EvJobPrint            *job,
-		     EvPrintOperationPrint *print)
+                     EvPrintOperationPrint *print)
 {
-	gtk_print_operation_cancel (print->op);
+        /* Finish the current page, so that draw-page
+         * is emitted again and it will cancel the
+         * print operation. If the job is still
+         * running, wait until it finishes.
+         */
+        if (ev_job_scheduler_get_running_thread_job () == print->job_print)
+                g_idle_add ((GSourceFunc)draw_page_finish_idle, print);
+        else
+                gtk_print_operation_draw_page_finish (print->op);
 }
 
 static void
@@ -1776,10 +1798,14 @@ ev_print_operation_print_draw_page (EvPrintOperationPrint *print,
 		g_signal_connect (G_OBJECT (print->job_print), "finished",
 				  G_CALLBACK (print_job_finished),
 				  (gpointer)print);
-		g_signal_connect (G_OBJECT (print->job_print), "cancelled",
-				  G_CALLBACK (print_job_cancelled),
-				  (gpointer)print);
-	}
+                g_signal_connect (G_OBJECT (print->job_print), "cancelled",
+                                  G_CALLBACK (print_job_cancelled),
+                                  (gpointer)print);
+	} else if (g_cancellable_is_cancelled (print->job_print->cancellable)) {
+                gtk_print_operation_cancel (print->op);
+                ev_job_print_set_cairo (EV_JOB_PRINT (print->job_print), NULL);
+                return;
+        }
 
 	ev_job_print_set_page (EV_JOB_PRINT (print->job_print), page);