Explain structver usage in sample defer plugin.

sample-plugins/defer/simple.c uses OPENVPN_PLUGINv3_STRUCTVER settings
that may not be obvious to a new author.  Add a comment to reduce
possible confusion.
Acked-by: David Sommerseth <davids@openvpn.net>
Message-Id: <1612163389-16421-1-git-send-email-gcox@mozilla.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg21540.html

Signed-off-by: Gert Doering <gert@greenie.muc.de>

diff --git a/sample/sample-plugins/defer/simple.c b/sample/sample-plugins/defer/simple.c
index 05bfc4efa6d85bb1696b6811428260f4cc5e9914..6f08bedd6319827c05786303f8a4007791042208 100644 (file)
--- a/sample/sample-plugins/defer/simple.c
+++ b/sample/sample-plugins/defer/simple.c
@@ -69,12 +69,18 @@ static plugin_log_t plugin_log = NULL;
  * Constants indicating minimum API and struct versions by the functions
  * in this plugin.  Consult openvpn-plugin.h, look for:
  * OPENVPN_PLUGIN_VERSION and OPENVPN_PLUGINv3_STRUCTVER
+ *
+ * Strictly speaking, this sample code only requires plugin_log, a feature
+ * of structver version 1.  However, '1' lines up with ancient versions
+ * of openvpn that are past end-of-support.  As such, we are requiring
+ * structver '5' here to indicate a desire for modern openvpn, rather
+ * than a need for any particular feature found in structver beyond '1'.
  */
 #define OPENVPN_PLUGIN_VERSION_MIN 3
 #define OPENVPN_PLUGIN_STRUCTVER_MIN 5
 
 /*
-* Our context, where we keep our state.
+ * Our context, where we keep our state.
  */
 
 struct plugin_context {
@@ -160,7 +166,6 @@ openvpn_plugin_open_v3(const int v3structver,
     const char **envp = args->envp;       /* environment variables */
     struct plugin_context *context;
 
-    /* Check API compatibility -- struct version 5 or higher needed */
     if (v3structver < OPENVPN_PLUGIN_STRUCTVER_MIN)
     {
         fprintf(stderr, "%s: this plugin is incompatible with the running version of OpenVPN\n", MODULE);
@@ -442,7 +447,6 @@ openvpn_plugin_func_v3(const int v3structver,
                        struct openvpn_plugin_args_func_in const *args,
                        struct openvpn_plugin_args_func_return *ret)
 {
-    /* Check API compatibility -- struct version 5 or higher needed */
     if (v3structver < OPENVPN_PLUGIN_STRUCTVER_MIN)
     {
         fprintf(stderr, "%s: this plugin is incompatible with the running version of OpenVPN\n", MODULE);