[gnome-control-center] printers: Check all supported CUPS commands, not just the first one

[Mario Sanchez Prada <msanchez src gnome org>]

commit c41bbfa7d0cd3c16e6ac144e8030bb60c6341053
Author: Mario Sanchez Prada <mario endlessm com>
Date:   Mon Jun 13 14:56:01 2016 +0100

    printers: Check all supported CUPS commands, not just the first one
    
    Use an array of strings to store every supported command and check
    the desired command against the elements in that list, instead of
    simply checking the first one.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=766861

 panels/printers/pp-maintenance-command.c |   34 ++++++++++++++++++++---------
 1 files changed, 23 insertions(+), 11 deletions(-)
---
diff --git a/panels/printers/pp-maintenance-command.c b/panels/printers/pp-maintenance-command.c
index 8f043d4..d03482e 100644
--- a/panels/printers/pp-maintenance-command.c
+++ b/panels/printers/pp-maintenance-command.c
@@ -296,9 +296,9 @@ _pp_maintenance_command_is_supported (const gchar *printer_name,
   ipp_t             *request;
   ipp_t             *response = NULL;
   gchar             *printer_uri;
-  gchar             *printer_commands = NULL;
-  gchar             *printer_commands_lowercase = NULL;
   gchar             *command_lowercase;
+  GPtrArray         *available_commands = NULL;
+  int                i;
 
   printer_uri = g_strdup_printf ("ipp://localhost/printers/%s",
                                  printer_name);
@@ -313,29 +313,41 @@ _pp_maintenance_command_is_supported (const gchar *printer_name,
     {
       if (ippGetStatusCode (response) <= IPP_OK_CONFLICT)
         {
+          int commands_count;
+
           attr = ippFindAttribute (response, "printer-commands", IPP_TAG_ZERO);
-          if (attr != NULL && ippGetCount (attr) > 0 &&
+          commands_count = attr != NULL ? ippGetCount (attr) : 0;
+          if (commands_count > 0 &&
               ippGetValueTag (attr) != IPP_TAG_NOVALUE &&
               (ippGetValueTag (attr) == IPP_TAG_KEYWORD))
             {
-              printer_commands = g_strdup (ippGetString (attr, 0, NULL));
+              available_commands = g_ptr_array_new_full (commands_count, g_free);
+              for (i = 0; i < commands_count; ++i)
+                {
+                  /* Array gains ownership of the lower-cased string */
+                  g_ptr_array_add (available_commands, g_ascii_strdown (ippGetString (attr, i, NULL), -1));
+                }
             }
         }
 
       ippDelete (response);
     }
 
-  if (printer_commands != NULL)
+  if (available_commands != NULL)
     {
       command_lowercase = g_ascii_strdown (command, -1);
-      printer_commands_lowercase = g_ascii_strdown (printer_commands, -1);
-
-      if (g_strcmp0 (printer_commands_lowercase, command_lowercase) == 0)
-        is_supported = TRUE;
+      for (i = 0; i < available_commands->len; ++i)
+        {
+          const gchar *available_command = g_ptr_array_index (available_commands, i);
+          if (g_strcmp0 (available_command, command_lowercase) == 0)
+            {
+              is_supported = TRUE;
+              break;
+            }
+        }
 
       g_free (command_lowercase);
-      g_free (printer_commands_lowercase);
-      g_free (printer_commands);
+      g_ptr_array_free (available_commands, TRUE);
     }
 
   g_free (printer_uri);