Fix: loglevel and model_emf_uri build fix

[lttng-ust.git] / include / lttng / ust-tracepoint-event.h

diff --git a/include/lttng/ust-tracepoint-event.h b/include/lttng/ust-tracepoint-event.h
index 48085670f937d7e0c5ce2c04a08d5b18bd20e526..6c1e3efa5192eb7b6fd61f400ecf5fde373e3be5 100644 (file)
--- a/include/lttng/ust-tracepoint-event.h
+++ b/include/lttng/ust-tracepoint-event.h
@@ -208,6 +208,7 @@ static const char                                                   \
 #define TRACEPOINT_EVENT_CLASS(_provider, _name, _args, _fields)                            \
        static const struct lttng_event_field __event_fields___##_provider##___##_name[] = { \
                _fields                                                                      \
+               ctf_integer(int, dummy, 0)      /* Dummy, C99 forbids 0-len array. */        \
        };
 
 #include TRACEPOINT_INCLUDE
@@ -618,8 +619,8 @@ void __event_probe__##_provider##___##_name(_TP_ARGS_DATA_PROTO(_args))           \
        size_t __event_len, __event_align;                                    \
        size_t __dynamic_len_idx = 0;                                         \
        union {                                                               \
-               size_t __dynamic_len[_TP_ARRAY_SIZE(__event_fields___##_provider##___##_name)]; \
-               char __filter_stack_data[2 * sizeof(unsigned long) * _TP_ARRAY_SIZE(__event_fields___##_provider##___##_name)]; \
+               size_t __dynamic_len[_TP_ARRAY_SIZE(__event_fields___##_provider##___##_name) - 1]; \
+               char __filter_stack_data[2 * sizeof(unsigned long) * (_TP_ARRAY_SIZE(__event_fields___##_provider##___##_name) - 1)]; \
        } __stackvar;                                                         \
        int __ret;                                                            \
                                                                              \
@@ -701,14 +702,29 @@ const char __tp_event_signature___##_provider##___##_name[] =             \
 /* Reset all macros within TRACEPOINT_EVENT */
 #include <lttng/ust-tracepoint-event-reset.h>
 
+/*
+ * Declare _loglevel___##__provider##___##__name as non-static, with
+ * hidden visibility for c++ handling of weakref. We do a weakref to the
+ * symbol in a later stage, which requires that the symbol is not
+ * mangled.
+ */
+#ifdef __cplusplus
+#define LTTNG_TP_EXTERN_C extern "C"
+#else
+#define LTTNG_TP_EXTERN_C
+#endif
+
 #undef TRACEPOINT_LOGLEVEL
 #define TRACEPOINT_LOGLEVEL(__provider, __name, __loglevel)               \
 static const int _loglevel_value___##__provider##___##__name = __loglevel; \
-static const int *_loglevel___##__provider##___##__name =                 \
+LTTNG_TP_EXTERN_C const int *_loglevel___##__provider##___##__name        \
+               __attribute__((visibility("hidden"))) =                    \
                &_loglevel_value___##__provider##___##__name;
 
 #include TRACEPOINT_INCLUDE
 
+#undef LTTNG_TP_EXTERN_C
+
 /*
  * Stage 6.1 of tracepoint event generation.
  *
@@ -718,12 +734,27 @@ static const int *_loglevel___##__provider##___##__name =            \
 /* Reset all macros within TRACEPOINT_EVENT */
 #include <lttng/ust-tracepoint-event-reset.h>
 
+/*
+ * Declare _model_emf_uri___##__provider##___##__name as non-static,
+ * with hidden visibility for c++ handling of weakref. We do a weakref
+ * to the symbol in a later stage, which requires that the symbol is not
+ * mangled.
+ */
+#ifdef __cplusplus
+#define LTTNG_TP_EXTERN_C extern "C"
+#else
+#define LTTNG_TP_EXTERN_C
+#endif
+
 #undef TRACEPOINT_MODEL_EMF_URI
 #define TRACEPOINT_MODEL_EMF_URI(__provider, __name, __uri)               \
-static const char *_model_emf_uri___##__provider##___##__name = __uri;
+LTTNG_TP_EXTERN_C const char *_model_emf_uri___##__provider##___##__name   \
+               __attribute__((visibility("hidden"))) = __uri;             \
 
 #include TRACEPOINT_INCLUDE
 
+#undef LTTNG_TP_EXTERN_C
+
 /*
  * Stage 7.1 of tracepoint event generation.
  *
@@ -748,7 +779,7 @@ const struct lttng_event_desc __event_desc___##_provider##_##_name = {             \
        .probe_callback = (void (*)(void)) &__event_probe__##_provider##___##_template,\
        .ctx = NULL,                                                           \
        .fields = __event_fields___##_provider##___##_template,                \
-       .nr_fields = _TP_ARRAY_SIZE(__event_fields___##_provider##___##_template), \
+       .nr_fields = _TP_ARRAY_SIZE(__event_fields___##_provider##___##_template) - 1, \
        .loglevel = &__ref_loglevel___##_provider##___##_name,                 \
        .signature = __tp_event_signature___##_provider##___##_template,       \
        .u = { .ext = { .model_emf_uri = &__ref_model_emf_uri___##_provider##___##_name } }, \
@@ -771,6 +802,7 @@ const struct lttng_event_desc __event_desc___##_provider##_##_name = {             \
 
 static const struct lttng_event_desc *_TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER)[] = {
 #include TRACEPOINT_INCLUDE
+       NULL,   /* Dummy, C99 forbids 0-len array. */
 };
 
 
@@ -784,7 +816,7 @@ static const struct lttng_event_desc *_TP_COMBINE_TOKENS(__event_desc___, TRACEP
 static struct lttng_probe_desc _TP_COMBINE_TOKENS(__probe_desc___, TRACEPOINT_PROVIDER) = {
        .provider = __tp_stringify(TRACEPOINT_PROVIDER),
        .event_desc = _TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER),
-       .nr_events = _TP_ARRAY_SIZE(_TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER)),
+       .nr_events = _TP_ARRAY_SIZE(_TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER)) - 1,
        .head = { NULL, NULL },
        .lazy_init_head = { NULL, NULL },
        .lazy = 0,