Rename "libside" to "libtgif"

[libside.git] / include / tgif / macros.h

diff --git a/include/tgif/macros.h b/include/tgif/macros.h
new file mode 100644 (file)
index 0000000..99d7b63
--- /dev/null
+++ b/include/tgif/macros.h
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2022 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#ifndef _TGIF_MACROS_H
+#define _TGIF_MACROS_H
+
+#include <stddef.h>
+#include <limits.h>
+
+/* Helper macros */
+
+#define TGIF_ARRAY_SIZE(arr)   (sizeof(arr) / sizeof((arr)[0]))
+
+/*
+ * Compound literals with static storage are needed by TGIF
+ * instrumentation.
+ * Compound literals are part of the C99 and C11 standards, but not
+ * part of the C++ standards. They are supported by most C++ compilers
+ * though.
+ *
+ * Example use:
+ * static struct mystruct *var = LTTNG_UST_COMPOUND_LITERAL(struct mystruct, { 1, 2, 3 });
+ */
+#define TGIF_COMPOUND_LITERAL(type, ...)   (type[]) { __VA_ARGS__ }
+
+#define tgif_likely(x)         __builtin_expect(!!(x), 1)
+#define tgif_unlikely(x)       __builtin_expect(!!(x), 0)
+
+#define TGIF_PARAM(...)        __VA_ARGS__
+
+/*
+ * tgif_container_of - Get the address of an object containing a field.
+ *
+ * @ptr: pointer to the field.
+ * @type: type of the object.
+ * @member: name of the field within the object.
+ */
+#define tgif_container_of(ptr, type, member)                           \
+       __extension__                                                   \
+       ({                                                              \
+               const __typeof__(((type *) NULL)->member) * __ptr = (ptr); \
+               (type *)((char *)__ptr - offsetof(type, member));       \
+       })
+
+#define tgif_struct_field_sizeof(_struct, _field) \
+       sizeof(((_struct * )NULL)->_field)
+
+#if defined(__SIZEOF_LONG__)
+#define TGIF_BITS_PER_LONG     (__SIZEOF_LONG__ * 8)
+#elif defined(_LP64)
+#define TGIF_BITS_PER_LONG     64
+#else
+#define TGIF_BITS_PER_LONG     32
+#endif
+
+#define TGIF_PACKED    __attribute__((packed))
+
+#endif /* _TGIF_MACROS_H */