pg_upgrade: Fix inconsistency in memory freeing

The function in charge of freeing the memory from a result created by
PQescapeIdentifier() has to be PQfreemem(), to ensure that both
allocation and free come from libpq.

One spot in pg_upgrade was not respecting that for pg_database's
datlocale (daticulocale in v16) when the collation provider is libc (aka
datlocale/daticulocale is NULL) with an allocation done using
pg_strdup() and a free with PQfreemem().  The code is changed to always
use PQescapeLiteral() when processing the input.

Oversight in 9637badd9f92.  This commit is similar to 48e4ae9a0707 and
5b94e2753439.

Author: Michael Paquier <michael@paquier.xyz>
Co-authored-by: Ranier Vilela <ranier.vf@gmail.com>
Discussion: https://postgr.es/m/Z601RQxTmIUohdkV@paquier.xyz
Backpatch-through: 16

diff --git a/src/bin/pg_upgrade/pg_upgrade.c b/src/bin/pg_upgrade/pg_upgrade.c
index 4562dafcff561ca615e781775a1df090896ff8ef..846fd65793f97629c69f60313d5bf144142c612c 100644 (file)
--- a/src/bin/pg_upgrade/pg_upgrade.c
+++ b/src/bin/pg_upgrade/pg_upgrade.c
@@ -383,6 +383,7 @@ set_locale_and_encoding(void)
        char       *datcollate_literal;
        char       *datctype_literal;
        char       *daticulocale_literal = NULL;
+       char       *daticulocale_src;
        DbLocaleInfo *locale = old_cluster.template0;
 
        prep_status("Setting locale and encoding for new cluster");
@@ -396,12 +397,10 @@ set_locale_and_encoding(void)
        datctype_literal = PQescapeLiteral(conn_new_template1,
                                                                           locale->db_ctype,
                                                                           strlen(locale->db_ctype));
-       if (locale->db_iculocale)
-               daticulocale_literal = PQescapeLiteral(conn_new_template1,
-                                                                                          locale->db_iculocale,
-                                                                                          strlen(locale->db_iculocale));
-       else
-               daticulocale_literal = pg_strdup("NULL");
+       daticulocale_src = locale->db_iculocale ? locale->db_iculocale : "NULL";
+       daticulocale_literal = PQescapeLiteral(conn_new_template1,
+                                                                                  daticulocale_src,
+                                                                                  strlen(daticulocale_src));
 
        /* update template0 in new cluster */
        if (GET_MAJOR_VERSION(new_cluster.major_version) >= 1500)