include/helper.h

   1 #ifndef _LTTNG_UST_HELPER_H
   2 #define _LTTNG_UST_HELPER_H
   3
   4 /*
   5  * Copyright (C) 2011  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; version 2.1 of
  10  * the License.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  20  */
  21
  22 #include <stdlib.h>
  23
  24 static inline __attribute__((always_inline))
  25 void *zmalloc(size_t len)
  26 {
  27         return calloc(len, 1);
  28 }
  29
  30 #define max_t(type, x, y)                               \
  31         ({                                              \
  32                 type __max1 = (x);                      \
  33                 type __max2 = (y);                      \
  34                 __max1 > __max2 ? __max1: __max2;       \
  35         })
  36
  37 #define min_t(type, x, y)                               \
  38         ({                                              \
  39                 type __min1 = (x);                      \
  40                 type __min2 = (y);                      \
  41                 __min1 <= __min2 ? __min1: __min2;      \
  42         })
  43
  44 #define LTTNG_ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
  45
  46 /*
  47  * Use of __builtin_return_address(0) sometimes seems to cause stack
  48  * corruption on 32-bit PowerPC. Disable this feature on that
  49  * architecture for now by always using the NULL value for the ip
  50  * context.
  51  */
  52 #if defined(__PPC__) && !defined(__PPC64__)
  53 #define LTTNG_UST_CALLER_IP()           NULL
  54 #else /* #if defined(__PPC__) && !defined(__PPC64__) */
  55 #define LTTNG_UST_CALLER_IP()           __builtin_return_address(0)
  56 #endif /* #else #if defined(__PPC__) && !defined(__PPC64__) */
  57
  58 /*
  59  * LTTNG_HIDDEN: set the hidden attribute for internal functions
  60  * On Windows, symbols are local unless explicitly exported,
  61  * see https://gcc.gnu.org/wiki/Visibility
  62  */
  63 #if defined(_WIN32) || defined(__CYGWIN__)
  64 #define LTTNG_HIDDEN
  65 #else
  66 #define LTTNG_HIDDEN __attribute__((visibility("hidden")))
  67 #endif
  68
  69 #endif /* _LTTNG_UST_HELPER_H */