common: replace container_of with a C++ safe implementation

[lttng-tools.git] / src / common / macros.hpp

diff --git a/src/common/macros.hpp b/src/common/macros.hpp
index ecaaa4cda2edbb0c6fdc273bf67c858ebaa2f2f7..37e6cabcf32e8701b369dab4ce96d3a17dc75724 100644 (file)
--- a/src/common/macros.hpp
+++ b/src/common/macros.hpp
@@ -229,14 +229,6 @@ void *memmove(T *d, const U *s, size_t n) = delete;
 #define ARRAY_SIZE(array)   (sizeof(array) / (sizeof((array)[0])))
 #endif
 
-#ifndef container_of
-#define container_of(ptr, type, member)                                        \
-       ({                                                              \
-               const typeof(((type *)NULL)->member) * __ptr = (ptr);   \
-               (type *)((char *)__ptr - offsetof(type, member));       \
-       })
-#endif
-
 #ifndef LTTNG_PACKED
 #define LTTNG_PACKED __attribute__((__packed__))
 #endif
@@ -317,4 +309,18 @@ int lttng_strncpy(char *dst, const char *src, size_t dst_len)
        return 0;
 }
 
+namespace lttng {
+namespace utils {
+template <class Parent, class Member>
+Parent *container_of(const Member *member, const Member Parent::*ptr_to_member)
+{
+       const Parent *dummy_parent = nullptr;
+       auto *offset_of_member = reinterpret_cast<const char *>(&(dummy_parent->*ptr_to_member));
+       auto address_of_parent = reinterpret_cast<const char *>(member) - offset_of_member;
+
+       return reinterpret_cast<Parent *>(address_of_parent);
+}
+} /* namespace utils */
+} /* namespace lttng */
+
 #endif /* _MACROS_H */