[gtk+/gtk-3-22] printing: Don't show duplicate printers

[Marek Kašík <mkasik src gnome org>]

commit 52e3c095bfdfb697e33509e0cef3bb5bf5ed7625
Author: Marek Kasik <mkasik redhat com>
Date:   Wed Aug 30 17:56:00 2017 +0200

    printing: Don't show duplicate printers
    
    Check UUID for printers obtained via DNSSD whether
    they are already installed on local CUPS server.
    Don't show such printers.
    
    Not all printers published via DNSSD have UUID entry though.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786794

 modules/printbackends/cups/gtkprintbackendcups.c |   64 +++++++++++++++++++++-
 modules/printbackends/cups/gtkprintercups.c      |    2 +
 modules/printbackends/cups/gtkprintercups.h      |    1 +
 3 files changed, 66 insertions(+), 1 deletions(-)
---
diff --git a/modules/printbackends/cups/gtkprintbackendcups.c 
b/modules/printbackends/cups/gtkprintbackendcups.c
index 2056434..f391c69 100644
--- a/modules/printbackends/cups/gtkprintbackendcups.c
+++ b/modules/printbackends/cups/gtkprintbackendcups.c
@@ -1899,7 +1899,8 @@ static const char * const printer_attrs[] =
     "ipp-versions-supported",
     "multiple-document-handling-supported",
     "copies-supported",
-    "number-up-supported"
+    "number-up-supported",
+    "device-uri"
   };
 
 /* Attributes we're interested in for printers without PPD */
@@ -1996,11 +1997,13 @@ typedef struct
   int       number_of_covers;
   gchar    *output_bin_default;
   GList    *output_bin_supported;
+  gchar    *original_device_uri;
 } PrinterSetupInfo;
 
 static void
 printer_setup_info_free (PrinterSetupInfo *info)
 {
+  g_free (info->original_device_uri);
   g_free (info->state_msg);
   g_strfreev (info->covers);
   g_slice_free (PrinterSetupInfo, info);
@@ -2376,6 +2379,10 @@ cups_printer_handle_attribute (GtkPrintBackendCups *cups_backend,
 
       info->output_bin_supported = g_list_reverse (info->output_bin_supported);
     }
+  else if (g_strcmp0 (ippGetName (attr), "device-uri") == 0)
+    {
+      info->original_device_uri = g_strdup (ippGetString (attr, 0, NULL));
+    }
   else
     {
       GTK_NOTE (PRINTING,
@@ -2464,6 +2471,7 @@ cups_create_printer (GtkPrintBackendCups *cups_backend,
 
   cups_printer->default_cover_before = g_strdup (info->default_cover_before);
   cups_printer->default_cover_after = g_strdup (info->default_cover_after);
+  cups_printer->original_device_uri = g_strdup (info->original_device_uri);
 
   if (info->default_number_up > 0)
     cups_printer->default_number_up = info->default_number_up;
@@ -2830,9 +2838,54 @@ typedef struct
   guint                printer_state;
   gchar               *type;
   gchar               *domain;
+  gchar               *UUID;
   GtkPrintBackendCups *backend;
 } AvahiConnectionTestData;
 
+static GtkPrinter *
+find_printer_by_uuid (GtkPrintBackendCups *backend,
+                      const gchar         *UUID)
+{
+  GtkPrinterCups *printer;
+  GtkPrinter     *result = NULL;
+  GList          *printers;
+  GList          *iter;
+  gchar          *printer_uuid;
+
+  printers = gtk_print_backend_get_printer_list (GTK_PRINT_BACKEND (backend));
+  for (iter = printers; iter != NULL; iter = iter->next)
+    {
+      printer = GTK_PRINTER_CUPS (iter->data);
+      if (printer->original_device_uri != NULL)
+        {
+          printer_uuid = g_strrstr (printer->original_device_uri, "uuid=");
+          if (printer_uuid != NULL && strlen (printer_uuid) >= 41)
+            {
+              printer_uuid += 5;
+              printer_uuid = g_strndup (printer_uuid, 36);
+
+#if GLIB_CHECK_VERSION(2, 52, 0)
+              if (g_uuid_string_is_valid (printer_uuid))
+#endif
+                {
+                  if (g_strcmp0 (printer_uuid, UUID) == 0)
+                    {
+                      result = GTK_PRINTER (printer);
+                      g_free (printer_uuid);
+                      break;
+                    }
+                }
+
+              g_free (printer_uuid);
+            }
+        }
+    }
+
+  g_list_free (printers);
+
+  return result;
+}
+
 /*
  *  Create new GtkPrinter from informations included in TXT records.
  */
@@ -2878,6 +2931,10 @@ create_cups_printer_from_avahi_data (AvahiConnectionTestData *data)
   set_info_state_message (info);
 
   printer = gtk_print_backend_find_printer (GTK_PRINT_BACKEND (data->backend), data->printer_name);
+
+  if (printer == NULL && data->UUID != NULL)
+    printer = find_printer_by_uuid (data->backend, data->UUID);
+
   if (printer == NULL)
     {
       printer = cups_create_printer (data->backend, info);
@@ -3080,6 +3137,11 @@ avahi_service_resolver_cb (GObject      *source_object,
                   if (data->printer_state != 0 || endptr != value)
                     data->got_printer_state = TRUE;
                 }
+              else if (g_strcmp0 (key, "UUID") == 0)
+                {
+                  if (*value != '\0')
+                    data->UUID = g_strdup (value);
+                }
 
               g_clear_pointer (&key, g_free);
               g_clear_pointer (&value, g_free);
diff --git a/modules/printbackends/cups/gtkprintercups.c b/modules/printbackends/cups/gtkprintercups.c
index 4a94cbd..068aba7 100644
--- a/modules/printbackends/cups/gtkprintercups.c
+++ b/modules/printbackends/cups/gtkprintercups.c
@@ -100,6 +100,7 @@ static void
 gtk_printer_cups_init (GtkPrinterCups *printer)
 {
   printer->device_uri = NULL;
+  printer->original_device_uri = NULL;
   printer->printer_uri = NULL;
   printer->state = 0;
   printer->hostname = NULL;
@@ -151,6 +152,7 @@ gtk_printer_cups_finalize (GObject *object)
   printer = GTK_PRINTER_CUPS (object);
 
   g_free (printer->device_uri);
+  g_free (printer->original_device_uri);
   g_free (printer->printer_uri);
   g_free (printer->hostname);
   g_free (printer->ppd_name);
diff --git a/modules/printbackends/cups/gtkprintercups.h b/modules/printbackends/cups/gtkprintercups.h
index 837035a..f26bbab 100644
--- a/modules/printbackends/cups/gtkprintercups.h
+++ b/modules/printbackends/cups/gtkprintercups.h
@@ -48,6 +48,7 @@ struct _GtkPrinterCups
   GtkPrinter parent_instance;
 
   gchar *device_uri;
+  gchar *original_device_uri;
   gchar *printer_uri;
   gchar *hostname;
   gint port;