Fix gs_probackup doesn't clean lockfile when exit.

src/bin/pg_probackup/catalog.cpp

@@ -66,7 +66,7 @@ timelineInfoFree(void *tliInfo)
 
 /* Iterate over locked backups and delete locks files */
 void
-unlink_lock_atexit(void)
+unlink_lock_atexit(bool fatal, void *userdata)
 {
     int i;
 

src/bin/pg_probackup/pg_probackup.cpp

@@ -537,12 +537,15 @@ static int do_validate_operate()
 
 static int do_actual_operate()
 {
+    int res = 0;
+    pgut_atexit_push(unlink_lock_atexit, NULL);
     switch (backup_subcmd)
     {
         case ADD_INSTANCE_CMD:
             return do_add_instance(&instance_config);
         case DELETE_INSTANCE_CMD:
-            return do_delete_instance();
+            res = do_delete_instance();
+            break;
         case INIT_CMD:
             return do_init();
         case BACKUP_CMD:
@@ -556,14 +559,17 @@ static int do_actual_operate()
                     elog(ERROR, "required parameter not specified: BACKUP_MODE "
                          "(-b, --backup-mode)");
 
-                return do_backup(start_time, set_backup_params, no_validate, no_sync, backup_logs, backup_replslots);
+                res = do_backup(start_time, set_backup_params, no_validate, no_sync, backup_logs, backup_replslots);
+                break;
             }
         case RESTORE_CMD:
-            return do_restore_or_validate(current.backup_id,
+            res = do_restore_or_validate(current.backup_id,
                             recovery_target_options,
                             restore_params, no_sync);
+            break;
         case VALIDATE_CMD:
-            return do_validate_operate();
+            res = do_validate_operate();
+            break;
         case SHOW_CMD:
             return do_show(instance_name, current.backup_id, show_archive);
         case DELETE_CMD:
@@ -589,10 +595,9 @@ static int do_actual_operate()
     }
 
     on_cleanup();
-    unlink_lock_atexit();
     release_logfile();
 
-    return 0;
+    return res;
 }
 
 static void parse_backup_option_to_params(char *command, char *command_name)

src/bin/pg_probackup/pg_probackupc.h

@@ -478,7 +478,7 @@ extern bool fio_is_remote_simple(fio_location location);
 extern void get_header_errormsg(Page page, char **errormsg);
 extern void get_checksum_errormsg(Page page, char **errormsg,
                                   BlockNumber absolute_blkno);
-extern void unlink_lock_atexit(void);
+extern void unlink_lock_atexit(bool fatal, void *userdata);
 
 extern bool
 datapagemap_is_set(datapagemap_t *map, BlockNumber blkno);

src/common/backend/utils/init/postinit.cpp

@@ -247,7 +247,7 @@ static HeapTuple GetDatabaseTuple(const char* dbname)
 
 char* GetDatabaseCompatibility(const char* dbname)
 {
-    if (!dbname)
+    if (!dbname || dbname[0] == 0)
         return NULL;
     HeapTuple tuple = GetDatabaseTuple(dbname);
     if (!tuple)