common: introduce bt_g_array_index

[babeltrace.git] / src / common / macros.h

diff --git a/src/common/macros.h b/src/common/macros.h
index 5549b8576fe251bd196a79b361bc054019d76239..ad4218c445f98caf104223b1499783f70ceb209d 100644 (file)
--- a/src/common/macros.h
+++ b/src/common/macros.h
@@ -11,18 +11,22 @@
 extern "C" {
 #endif
 
+#ifdef __cplusplus
+#define BT_EXTERN_C extern "C"
+#else
+#define BT_EXTERN_C
+#endif
+
 #define bt_max_t(type, a, b)   \
        ((type) (a) > (type) (b) ? (type) (a) : (type) (b))
 
 /*
- * BT_HIDDEN: set the hidden attribute for internal functions
- * On Windows, symbols are local unless explicitly exported,
- * see https://gcc.gnu.org/wiki/Visibility
+ * BT_EXPORT: set the visibility for exported functions.
  */
 #if defined(_WIN32) || defined(__CYGWIN__)
-#define BT_HIDDEN
+#define BT_EXPORT
 #else
-#define BT_HIDDEN __attribute__((visibility("hidden")))
+#define BT_EXPORT __attribute__((visibility("default")))
 #endif
 
 /*
@@ -48,6 +52,10 @@ extern "C" {
                _ref;                   \
        })
 
+/* Wrapper for g_array_index that adds bound checking.  */
+#define bt_g_array_index(a, t, i)              \
+       g_array_index((a), t, ({ BT_ASSERT_DBG((i) < (a)->len); (i); }))
+
 /*
  * Copied from:
  * <https://stackoverflow.com/questions/37411809/how-to-elegantly-fix-this-unused-variable-warning/37412551#37412551>:
@@ -75,6 +83,17 @@ extern "C" {
        ((void) sizeof((void) (_expr1), (void) (_expr2),                \
                (void) (_expr3), (void) (_expr4), (void) (_expr5), 0))
 
+#if defined __clang__
+#  if __has_warning("-Wunused-but-set-variable")
+#    define BT_DIAG_IGNORE_UNUSED_BUT_SET_VARIABLE \
+       _Pragma("GCC diagnostic ignored \"-Wunused-but-set-variable\"")
+#  endif
+#endif
+
+#if !defined BT_DIAG_IGNORE_UNUSED_BUT_SET_VARIABLE
+#  define BT_DIAG_IGNORE_UNUSED_BUT_SET_VARIABLE
+#endif
+
 #ifdef __cplusplus
 }
 #endif