include/helper.h

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  */
   6
   7 #ifndef _LTTNG_UST_HELPER_H
   8 #define _LTTNG_UST_HELPER_H
   9
  10 #include <stdlib.h>
  11
  12 static inline __attribute__((always_inline))
  13 void *zmalloc(size_t len)
  14 {
  15         return calloc(len, 1);
  16 }
  17
  18 #define max_t(type, x, y)                               \
  19         ({                                              \
  20                 type __max1 = (x);                      \
  21                 type __max2 = (y);                      \
  22                 __max1 > __max2 ? __max1: __max2;       \
  23         })
  24
  25 #define min_t(type, x, y)                               \
  26         ({                                              \
  27                 type __min1 = (x);                      \
  28                 type __min2 = (y);                      \
  29                 __min1 <= __min2 ? __min1: __min2;      \
  30         })
  31
  32 #define LTTNG_ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
  33
  34 /*
  35  * Use of __builtin_return_address(0) sometimes seems to cause stack
  36  * corruption on 32-bit PowerPC. Disable this feature on that
  37  * architecture for now by always using the NULL value for the ip
  38  * context.
  39  */
  40 #if defined(__PPC__) && !defined(__PPC64__)
  41 #define LTTNG_UST_CALLER_IP()           NULL
  42 #else /* #if defined(__PPC__) && !defined(__PPC64__) */
  43 #define LTTNG_UST_CALLER_IP()           __builtin_return_address(0)
  44 #endif /* #else #if defined(__PPC__) && !defined(__PPC64__) */
  45
  46 /*
  47  * LTTNG_HIDDEN: set the hidden attribute for internal functions
  48  * On Windows, symbols are local unless explicitly exported,
  49  * see https://gcc.gnu.org/wiki/Visibility
  50  */
  51 #if defined(_WIN32) || defined(__CYGWIN__)
  52 #define LTTNG_HIDDEN
  53 #else
  54 #define LTTNG_HIDDEN __attribute__((visibility("hidden")))
  55 #endif
  56
  57 #endif /* _LTTNG_UST_HELPER_H */