From e4e81a0fb164016da72609bcb7486a695a3fb7b9 Mon Sep 17 00:00:00 2001
From: "Roger A. Light" <roger@atchoo.org>
Date: Sun, 19 Feb 2017 20:45:52 +0000
Subject: [PATCH] [111] Add mosquitto_userdata function to libmosquitto.

This allows retrieving mosq->userdata.

Bug: https://github.com/eclipse/mosquitto/issues/111
---
 ChangeLog.txt      |  2 ++
 lib/linker.version |  1 +
 lib/mosquitto.h    | 19 +++++++++++++++++--
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/ChangeLog.txt b/ChangeLog.txt
index abb98349..092880e6 100644
--- a/ChangeLog.txt
+++ b/ChangeLog.txt
@@ -54,6 +54,8 @@ Client library:
   according to the UTF-8 spec and to the additional restrictions imposed by
   the MQTT spec.
 - Topic inputs are checked for UTF-8 validity.
+- Add mosquitto_userdata function to allow retrieving the client userdata
+  member variable. Closes #111.
 
 Client:
 - Add -F to mosquitto_sub to allow the user to choose the output format.
diff --git a/lib/linker.version b/lib/linker.version
index 6b03f66d..e07682a1 100644
--- a/lib/linker.version
+++ b/lib/linker.version
@@ -85,4 +85,5 @@ MOSQ_1.5 {
 		mosquitto_subscribe_callback;
 		mosquitto_message_free_contents;
 		mosquitto_validate_utf8;
+		mosquitto_userdata;
 } MOSQ_1.4;
diff --git a/lib/mosquitto.h b/lib/mosquitto.h
index 70268260..0f8154aa 100644
--- a/lib/mosquitto.h
+++ b/lib/mosquitto.h
@@ -1002,7 +1002,8 @@ libmosq_EXPORT int mosquitto_opts_set(struct mosquitto *mosq, enum mosq_opt_t op
  *                Your callback must write the password into "buf", which is
  *                "size" bytes long. The return value must be the length of the
  *                password. "userdata" will be set to the calling mosquitto
- *                instance.
+ *                instance. The mosquitto userdata member variable can be
+ *                retrieved using <mosquitto_userdata>.
  *
  * Returns:
  *	MOSQ_ERR_SUCCESS - on success.
@@ -1010,7 +1011,8 @@ libmosq_EXPORT int mosquitto_opts_set(struct mosquitto *mosq, enum mosq_opt_t op
  * 	MOSQ_ERR_NOMEM -   if an out of memory condition occurred.
  *
  * See Also:
- *	<mosquitto_tls_opts_set>, <mosquitto_tls_psk_set>, <mosquitto_tls_insecure_set>
+ *	<mosquitto_tls_opts_set>, <mosquitto_tls_psk_set>,
+ *	<mosquitto_tls_insecure_set>, <mosquitto_userdata>
  */
 libmosq_EXPORT int mosquitto_tls_set(struct mosquitto *mosq,
 		const char *cafile, const char *capath,
@@ -1692,6 +1694,19 @@ libmosq_EXPORT int mosquitto_subscribe_callback(
  */
 libmosq_EXPORT int mosquitto_validate_utf8(const char *str, int len);
 
+
+/* Function: mosquitto_userdata
+ *
+ * Retrieve the "userdata" variable for a mosquitto client.
+ *
+ * Parameters:
+ * 	mosq - a valid mosquitto instance.
+ *
+ * Returns:
+ *	A pointer to the userdata member variable.
+ */
+libmosq_EXPORT void *mosquitto_userdata(struct mosquitto *mosq);
+
 #ifdef __cplusplus
 }
 #endif