Fix: Pointers are rejected by integer element compile time assertion for array and...

[lttng-ust.git] / include / lttng / ust-utils.h

diff --git a/include/lttng/ust-utils.h b/include/lttng/ust-utils.h
index baca88f271184840512ea97745320d8bef65e333..25b8c7fdb835d55c9f815278c4c2aa1386c1a648 100644 (file)
--- a/include/lttng/ust-utils.h
+++ b/include/lttng/ust-utils.h
@@ -28,7 +28,11 @@
  *
  * Returns true if the type of @type is signed.
  */
-#define lttng_ust_is_signed_type(type)           ((type) -1 < (type) 1)
+#if defined(__cplusplus)
+#define lttng_ust_is_signed_type(type) (std::is_signed<type>::value)
+#else
+#define lttng_ust_is_signed_type(type) ((type) -1 < (type) 1)
+#endif
 
 
 /**
@@ -55,15 +59,29 @@
 #endif
 
 /**
- * lttng_ust_ctf_array_element_type_is_supported -
+ * lttng_ust_is_pointer_type - check if type is a pointer
+ *
+ * Returns true if the type of @type is a pointer.
+ */
+#if defined(__cplusplus)
+#define lttng_ust_is_pointer_type(type) (std::is_pointer<type>::value)
+#else
+/* The difference between two pointers is an integer. */
+#define lttng_ust_is_pointer_type(type) \
+       (lttng_ust_is_integer_type(typeof(((type)0 - (type)0))) && !lttng_ust_is_integer_type(type))
+#endif
+
+
+/**
+ * lttng_ust_field_array_element_type_is_supported -
  *
- * Adds a compilation assertion that CTF arrays and sequences declared by the
- * user are of an integral type.
+ * Adds a compilation assertion that array and sequence fields declared by the
+ * user are of an integral or pointer type.
  */
-#define lttng_ust_ctf_array_element_type_is_supported(type, item) \
-               lttng_static_assert(lttng_ust_is_integer_type(type), \
-                       "Non-integer type `" #item "` not supported as element of CTF_ARRAY or CTF_SEQUENCE", \
-                       Non_integer_type__##item##__not_supported_as_element_of_CTF_ARRAY_or_CTF_SEQUENCE);
+#define lttng_ust_field_array_element_type_is_supported(type, item) \
+               lttng_ust_static_assert(lttng_ust_is_integer_type(type) || lttng_ust_is_pointer_type(type), \
+                       "Non-integer, non-pointer type `" #item "` not supported as element of LTTNG_UST_FIELD_ARRAY or LTTNG_UST_FIELD_SEQUENCE", \
+                       Non_integer_type__##item##__not_supported_as_element_of_LTTNG_UST_FIELD_ARRAY_or_LTTNG_UST_FIELD_SEQUENCE)
 
 
 /**
@@ -134,7 +152,7 @@
  * @align_drift:  object offset from an "alignment"-aligned address.
  * @alignment:    natural object alignment. Must be non-zero, power of 2.
  *
- * Returns the offset that must be substracted to align towards lower addresses.
+ * Returns the offset that must be subtracted to align towards lower addresses.
  */
 #define lttng_ust_offset_align_floor(align_drift, alignment)                  \
        ({                                                                     \