From 16ee4b6f0d3a89c38844e736c0d5f57e5dfd523f Mon Sep 17 00:00:00 2001
From: Lukas Geyer <lukasgeyer@user.github.invalid.com>
Date: Tue, 28 Feb 2017 21:17:25 +0800
Subject: [PATCH] client: allow change externally-defined wsi user_data

https://github.com/warmcat/libwebsockets/issues/819

AG: add explanation in doxygen comment and check user_space was externally set
---
 lib/libwebsockets.c | 10 ++++++++++
 lib/libwebsockets.h | 13 +++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/lib/libwebsockets.c b/lib/libwebsockets.c
index a2d8328ae..9c990866e 100755
--- a/lib/libwebsockets.c
+++ b/lib/libwebsockets.c
@@ -1374,6 +1374,16 @@ lws_wsi_user(struct lws *wsi)
 	return wsi->user_space;
 }
 
+LWS_VISIBLE LWS_EXTERN void
+lws_set_wsi_user(struct lws *wsi, void *data)
+{
+	if (wsi->user_space_externally_allocated)
+		wsi->user_space = data;
+	else
+		lwsl_err("%s: Cannot set internally-allocated user_space\n",
+			 __func__);
+}
+
 LWS_VISIBLE LWS_EXTERN struct lws *
 lws_get_parent(const struct lws *wsi)
 {
diff --git a/lib/libwebsockets.h b/lib/libwebsockets.h
index 90f5faa9e..b1e5d9f5d 100644
--- a/lib/libwebsockets.h
+++ b/lib/libwebsockets.h
@@ -3902,6 +3902,19 @@ lws_get_library_version(void);
 LWS_VISIBLE LWS_EXTERN void *
 lws_wsi_user(struct lws *wsi);
 
+/**
+ * lws_wsi_set_user() - set the user data associated with the client connection
+ * \param wsi: lws connection
+ * \param user: user data
+ *
+ * By default lws allocates this and it's not legal to externally set it
+ * yourself.  However client connections may have it set externally when the
+ * connection is created... if so, this api can be used to modify it at
+ * runtime additionally.
+ */
+LWS_VISIBLE LWS_EXTERN void
+lws_set_wsi_user(struct lws *wsi, void *user);
+
 /**
  * lws_parse_uri:	cut up prot:/ads:port/path into pieces
  *			Notice it does so by dropping '\0' into input string