From 1e700b7d3cd091b474c3f319e4996f321db1f5f7 Mon Sep 17 00:00:00 2001
From: Simon Marchi <simon.marchi@efficios.com>
Date: Tue, 13 Feb 2024 11:00:46 -0500
Subject: [PATCH] cpp-common/bt2: add const_cast when setting user data

If the user data type is specified as a const type,
`static_cast<void *>` will not work.  Fix that by doing a static_cast to
`const void *` then a const_cast to `void *`.

Change-Id: Ic39c9c25da1899defe4edf8c8e800297fbf2fb2d
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/11799
Tested-by: jenkins <jenkins@lttng.org>
Reviewed-by: Philippe Proulx <eeppeliteloop@gmail.com>
---
 src/cpp-common/bt2/self-component-port.hpp   | 6 ++++--
 src/cpp-common/bt2/self-message-iterator.hpp | 3 ++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/cpp-common/bt2/self-component-port.hpp b/src/cpp-common/bt2/self-component-port.hpp
index 2551064e..5b34abfd 100644
--- a/src/cpp-common/bt2/self-component-port.hpp
+++ b/src/cpp-common/bt2/self-component-port.hpp
@@ -102,7 +102,8 @@ public:
     template <typename T>
     void data(T& obj) const noexcept
     {
-        bt_self_component_set_data(this->libObjPtr(), static_cast<void *>(&obj));
+        bt_self_component_set_data(this->libObjPtr(),
+                                   const_cast<void *>(static_cast<const void *>(&obj)));
     }
 
     bt2::TraceClass::Shared createTraceClass() const
@@ -148,7 +149,8 @@ protected:
     {
         LibPortT *libPortPtr;
 
-        const auto status = func(this->libObjPtr(), name, static_cast<void *>(data), &libPortPtr);
+        const auto status = func(this->libObjPtr(), name,
+                                 const_cast<void *>(static_cast<const void *>(data)), &libPortPtr);
 
         switch (status) {
         case BT_SELF_COMPONENT_ADD_PORT_STATUS_OK:
diff --git a/src/cpp-common/bt2/self-message-iterator.hpp b/src/cpp-common/bt2/self-message-iterator.hpp
index e333cb1a..4460fe27 100644
--- a/src/cpp-common/bt2/self-message-iterator.hpp
+++ b/src/cpp-common/bt2/self-message-iterator.hpp
@@ -69,7 +69,8 @@ public:
     template <typename T>
     void data(T& obj) const noexcept
     {
-        bt_self_message_iterator_set_data(this->libObjPtr(), static_cast<void *>(&obj));
+        bt_self_message_iterator_set_data(this->libObjPtr(),
+                                          const_cast<void *>(static_cast<const void *>(&obj)));
     }
 
     bt2::StreamBeginningMessage::Shared
-- 
2.34.1