In pg_upgrade, report pre-PG 8.1 plpython helper functions left in the

public schema that no longer point to valid shared object libraries, and
suggest a solution.

diff --git a/contrib/pg_upgrade/function.c b/contrib/pg_upgrade/function.c
index 90e8a9f58110c2df49a32c901ae39a2b8466bbcc..b4b17badb28ce8abfa2f946c33572c01f98fa021 100644 (file)
--- a/contrib/pg_upgrade/function.c
+++ b/contrib/pg_upgrade/function.c
@@ -132,7 +132,8 @@ get_loadable_libraries(void)
        PGresult  **ress;
        int                     totaltups;
        int                     dbnum;
-
+       bool            found_public_plpython_handler = false;
+       
        ress = (PGresult **) pg_malloc(old_cluster.dbarr.ndbs * sizeof(PGresult *));
        totaltups = 0;
 
@@ -157,9 +158,67 @@ get_loadable_libraries(void)
                                                                                FirstNormalObjectId);
                totaltups += PQntuples(ress[dbnum]);
 
+                /*
+                 *     Systems that install plpython before 8.1 have
+                 *     plpython_call_handler() defined in the "public" schema, causing
+                 *     pg_dumpall to dump it.  However that function still references
+                 *     "plpython" (no "2"), so it throws an error on restore.  This code
+                 *     checks for the problem function, reports affected databases to the
+                 *     user and explains how to remove them.
+                 *     8.1 git commit: e0dedd0559f005d60c69c9772163e69c204bac69
+                 *     http://archives.postgresql.org/pgsql-hackers/2012-03/msg01101.php
+                 *     http://archives.postgresql.org/pgsql-bugs/2012-05/msg00206.php
+                 */
+               if (GET_MAJOR_VERSION(old_cluster.major_version) < 901)
+               {
+                       PGresult  *res;
+
+                       res = executeQueryOrDie(conn,
+                                                                       "SELECT 1 "
+                                                                       "FROM   pg_catalog.pg_proc JOIN pg_namespace "
+                                                                       "               ON pronamespace = pg_namespace.oid "
+                                                                       "WHERE proname = 'plpython_call_handler' AND "
+                                                                       "nspname = 'public' AND "
+                                                                       "prolang = 13 /* C */ AND "
+                                                                       "probin = '$libdir/plpython' AND "
+                                                                       "pg_proc.oid >= %u;",
+                                                                       FirstNormalObjectId);
+                       if (PQntuples(res) > 0)
+                       {
+                               if (!found_public_plpython_handler)
+                               {
+                                       pg_log(PG_WARNING,
+                  "\nThe old cluster has a \"plpython_call_handler\" function defined\n"
+                       "in the \"public\" schema which is a duplicate of the one defined\n"
+                   "in the \"pg_catalog\" schema.  You can confirm this by executing\n"
+                       "in psql:\n"
+                       "\n"
+                       "       \\df *.plpython_call_handler\n"
+                       "\n"
+                       "The \"public\" schema version of this function was created by a\n"
+                       "pre-8.1 install of plpython, and must be removed for pg_upgrade\n"
+                       "to complete because it references a now-obsolete \"plpython\"\n"
+                       "shared object file.  You can remove the \"public\" schema version\n"
+                       "of this function by running the following command:\n"
+                       "\n"
+                       "       DROP FUNCTION public.plpython_call_handler()\n"
+                       "\n"
+                       "in each affected database:\n"
+                       "\n");
+                               }
+                               pg_log(PG_WARNING, "    %s\n", active_db->db_name);
+                               found_public_plpython_handler = true;
+                       }
+                       PQclear(res);
+               }
+
                PQfinish(conn);
        }
 
+       if (found_public_plpython_handler)
+               pg_log(PG_FATAL,
+                  "Remove the problem functions from the old cluster to continue.\n");
+       
        totaltups++;    /* reserve for pg_upgrade_support */
 
        /* Allocate what's certainly enough space */
@@ -245,12 +304,6 @@ check_loadable_libraries(void)
                 *      For this case, we could check pg_pltemplate, but that only works
                 *      for languages, and does not help with function shared objects,
                 *      so we just do a general fix.
-                *
-                *      Some systems have plpython_call_handler() that references
-                *      "plpython" defined in the "public" schema, causing pg_dump to
-                *      dump it an generate an error on pg_dumpall restore;  not sure
-                *      on the cause, see:
-                *      http://archives.postgresql.org/pgsql-hackers/2012-03/msg01101.php
                 */
                if (GET_MAJOR_VERSION(old_cluster.major_version) < 901 &&
                        strcmp(lib, "$libdir/plpython") == 0)