From 330242959d5efdffd2aed378ea96cc7aa5cb9bde Mon Sep 17 00:00:00 2001
From: Richard Levitte <levitte@openssl.org>
Date: Wed, 5 Jul 2017 16:00:30 +0200
Subject: [PATCH] STORE: Add info on the expected post_process callback
 behavior

Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/3856)
---
 doc/man3/OSSL_STORE_open.pod | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/doc/man3/OSSL_STORE_open.pod b/doc/man3/OSSL_STORE_open.pod
index 0bc6d5ccfd..3a05a88077 100644
--- a/doc/man3/OSSL_STORE_open.pod
+++ b/doc/man3/OSSL_STORE_open.pod
@@ -55,6 +55,10 @@ The given B<ui_method> and B<ui_data_data> will be reused by all
 functions that use B<OSSL_STORE_CTX> when interaction is needed.
 The given B<post_process> and B<post_process_data> will be reused by
 OSSL_STORE_load() to manipulate or drop the value to be returned.
+The B<post_process> function drops values by returning B<NULL>, which
+will cause OSSL_STORE_load() to start its process over with loading
+the next object, until B<post_process> returns something other than
+B<NULL>, or the end of data is reached as indicated by OSSL_STORE_eof().
 
 OSSL_STORE_ctrl() takes a B<OSSL_STORE_CTX>, and command number B<cmd> and
 more arguments not specified here.