src/compiler.h

   1 /*
   2  * netsniff-ng - the packet sniffing beast
   3  * By Daniel Borkmann <daniel@netsniff-ng.org>
   4  * Copyright 2009, 2010 Daniel Borkmann.
   5  * Subject to the GPL, version 2.
   6  */
   7
   8 #ifndef COMPILER_H
   9 #define COMPILER_H
  10
  11 #ifndef __aligned_16
  12 # define __aligned_16           __attribute__((aligned(16)))
  13 #endif
  14
  15 #ifndef likely
  16 # define likely(x)              __builtin_expect(!!(x), 1)
  17 #endif
  18
  19 #ifndef unlikely
  20 # define unlikely(x)            __builtin_expect(!!(x), 0)
  21 #endif
  22
  23 #ifndef __deprecated
  24 # define __deprecated           /* unimplemented */
  25 #endif
  26
  27 #ifndef unreachable
  28 # define unreachable()          do { } while (1)
  29 #endif
  30
  31 #ifndef __read_mostly
  32 # define __read_mostly          __attribute__((__section__(".data.read_mostly")))
  33 #endif
  34
  35 #ifndef noinline
  36 # define noinline               __attribute__((noinline))
  37 #endif
  38
  39 #ifndef __always_inline
  40 # define __always_inline        inline
  41 #endif
  42
  43 #ifndef __hidden
  44 # define __hidden               __attribute__((visibility("hidden")))
  45 #endif
  46
  47 #ifndef __pure
  48 # define __pure                 __attribute__ ((pure))
  49 #endif
  50
  51 #ifndef max
  52 # define max(a, b)                         \
  53         ({                                 \
  54                 typeof (a) _a = (a);       \
  55                 typeof (b) _b = (b);       \
  56                 _a > _b ? _a : _b;         \
  57         })
  58 #endif /* max */
  59
  60 #ifndef min
  61 # define min(a, b)                         \
  62         ({                                 \
  63                 typeof (a) _a = (a);       \
  64                 typeof (b) _b = (b);       \
  65                 _a < _b ? _a : _b;         \
  66         })
  67 #endif /* min */
  68
  69 /* from the Linux kernel, GPLv2 */
  70 #ifndef offsetof
  71 # define offsetof(type, member) ((size_t) &((type *) 0)->member)
  72 #endif
  73
  74 #ifndef container_of
  75 # define container_of(ptr, type, member)                             \
  76         ({                                                           \
  77                 const typeof(((type *) 0)->member) * __mptr = (ptr); \
  78                 (type *) ((char *) __mptr - offsetof(type, member)); \
  79         })
  80 #endif
  81
  82 #endif /* COMPILER_H */