Fix duplicate local printers using UUID comparison (Issue #1531)

Updated fix based on michaelrsweet feedback:
- Added printer-uuid to pattrs array in _cupsGetDests()
- Compare UUID from DNS-SD TXT record against local queue
  printer-uuid values in cups_dest_query_cb()
- UUID is guaranteed unique unlike rp value

diff --git a/cups/dest.c b/cups/dest.c
index 38dd66436eb8935b652ffe4997e2eabd0d13e087..aab4f36bcc8580d88b2e59f5b166b74f2781f179 100644 (file)
--- a/cups/dest.c
+++ b/cups/dest.c
@@ -1309,7 +1309,8 @@ _cupsGetDests(http_t       *http, /* I  - Connection to server or
                  "printer-state-change-time",
                  "printer-state-reasons",
                  "printer-type",
-                 "printer-uri-supported"
+                 "printer-uri-supported",
+                  "printer-uuid"
                };
 
 
@@ -2847,22 +2848,23 @@ cups_dest_query_cb(
         if (!have_pdf && !have_raster)
           device->state = _CUPS_DNSSD_INCOMPATIBLE;
       }
-      else if (!_cups_strcasecmp(key, "rp"))
+      else if (!_cups_strcasecmp(key, "UUID"))
       {
         // Suppress local printer being re-discovered via DNS-SD
-        const char *rp_name = value;
-        int        i;
-
-        if (!_cups_strncasecmp(rp_name, "printers/", 9))
-          rp_name += 9;
+        int i;
 
         for (i = 0; i < data->num_local; i++)
         {
-          if (!_cups_strcasecmp(rp_name, data->local_dests[i].name))
+          const char *local_uuid = cupsGetOption("printer-uuid",
+                                      data->local_dests[i].num_options,
+                                      data->local_dests[i].options);
+
+          if (local_uuid && !_cups_strcasecmp(value, local_uuid))
           {
             device->state = _CUPS_DNSSD_INCOMPATIBLE;
             DEBUG_printf("6cups_dest_query_cb: "
-                "Suppressing local printer '%s'.", rp_name);
+                "Suppressing local printer '%s' (UUID match).",
+                device->dest.name);
             break;
           }
         }