lib/birdlib.h

   1 /*
   2  *      BIRD Library
   3  *
   4  *      (c) 1998--2004 Martin Mares <mj@ucw.cz>
   5  *
   6  *      Can be freely distributed and used under the terms of the GNU GPL.
   7  */
   8
   9 #ifndef _BIRD_BIRDLIB_H_
  10 #define _BIRD_BIRDLIB_H_
  11
  12 #include "timer.h"
  13 #include "alloca.h"
  14
  15 /* Ugly structure offset handling macros */
  16
  17 #define OFFSETOF(s, i) ((size_t) &((s *)0)->i)
  18 #define SKIP_BACK(s, i, p) ((s *)((char *)p - OFFSETOF(s, i)))
  19 #define BIRD_ALIGN(s, a) (((s)+a-1)&~(a-1))
  20
  21 /* Utility macros */
  22
  23 #define MIN_(a,b) (((a)<(b))?(a):(b))
  24 #define MAX_(a,b) (((a)>(b))?(a):(b))
  25
  26 #ifndef PARSER
  27 #undef MIN
  28 #undef MAX
  29 #define MIN(a,b) MIN_(a,b)
  30 #define MAX(a,b) MAX_(a,b)
  31 #endif
  32
  33 #define U64(c) UINT64_C(c)
  34 #define ABS(a)   ((a)>=0 ? (a) : -(a))
  35 #define DELTA(a,b) (((a)>=(b))?(a)-(b):(b)-(a))
  36 #define ARRAY_SIZE(a) (sizeof(a)/sizeof(*(a)))
  37
  38
  39 /* Bitfield macros */
  40
  41 /* b is u32 array (or ptr), l is size of it in bits (multiple of 32), p is 0..(l-1) */
  42 #define BIT32_VAL(p)            (((u32) 1) << ((p) % 32))
  43 #define BIT32_TEST(b,p)         ((b)[(p)/32] & BIT32_VAL(p))
  44 #define BIT32_SET(b,p)          ((b)[(p)/32] |= BIT32_VAL(p))
  45 #define BIT32_CLR(b,p)          ((b)[(p)/32] &= ~BIT32_VAL(p))
  46 #define BIT32_ZERO(b,l)         memset((b), 0, (l)/8)
  47
  48 #ifndef NULL
  49 #define NULL ((void *) 0)
  50 #endif
  51
  52 #ifndef IPV6
  53 #define IP_VERSION 4
  54 #else
  55 #define IP_VERSION 6
  56 #endif
  57
  58
  59 /* Macros for gcc attributes */
  60
  61 #define NORET __attribute__((noreturn))
  62 #define UNUSED __attribute__((unused))
  63
  64
  65 /* Microsecond time */
  66
  67 typedef s64 btime;
  68
  69 #define S_      *1000000
  70 #define MS_     *1000
  71 #define US_     *1
  72 #define TO_S    /1000000
  73 #define TO_MS   /1000
  74 #define TO_US   /1
  75
  76 #ifndef PARSER
  77 #define S       S_
  78 #define MS      MS_
  79 #define US      US_
  80 #endif
  81
  82
  83 /* Rate limiting */
  84
  85 struct tbf {
  86   bird_clock_t timestamp;               /* Last update */
  87   u16 count;                            /* Available tokens */
  88   u16 burst;                            /* Max number of tokens */
  89   u16 rate;                             /* Rate of replenishment */
  90   u16 mark;                             /* Whether last op was limited */
  91 };
  92
  93 /* Default TBF values for rate limiting log messages */
  94 #define TBF_DEFAULT_LOG_LIMITS { .rate = 1, .burst = 5 }
  95
  96 void tbf_update(struct tbf *f);
  97
  98 static inline int
  99 tbf_limit(struct tbf *f)
 100 {
 101   tbf_update(f);
 102
 103   if (!f->count)
 104   {
 105     f->mark = 1;
 106     return 1;
 107   }
 108
 109   f->count--;
 110   f->mark = 0;
 111   return 0;
 112 }
 113
 114
 115 /* Logging and dying */
 116
 117 typedef struct buffer {
 118   byte *start;
 119   byte *pos;
 120   byte *end;
 121 } buffer;
 122
 123 #define STACK_BUFFER_INIT(buf,size)             \
 124   do {                                          \
 125     buf.start = alloca(size);                   \
 126     buf.pos = buf.start;                        \
 127     buf.end = buf.start + size;                 \
 128   } while(0)
 129
 130 #define LOG_BUFFER_INIT(buf)                    \
 131   STACK_BUFFER_INIT(buf, LOG_BUFFER_SIZE)
 132
 133 #define LOG_BUFFER_SIZE 1024
 134
 135 #define log log_msg
 136 void log_commit(int class, buffer *buf);
 137 void log_msg(const char *msg, ...);
 138 void log_rl(struct tbf *rl, const char *msg, ...);
 139 void die(const char *msg, ...) NORET;
 140 void bug(const char *msg, ...) NORET;
 141
 142 #define L_DEBUG "\001"                  /* Debugging messages */
 143 #define L_TRACE "\002"                  /* Protocol tracing */
 144 #define L_INFO "\003"                   /* Informational messages */
 145 #define L_REMOTE "\004"                 /* Remote protocol errors */
 146 #define L_WARN "\005"                   /* Local warnings */
 147 #define L_ERR "\006"                    /* Local errors */
 148 #define L_AUTH "\007"                   /* Authorization failed etc. */
 149 #define L_FATAL "\010"                  /* Fatal errors */
 150 #define L_BUG "\011"                    /* BIRD bugs */
 151
 152 void debug(const char *msg, ...);               /* Printf to debug output */
 153
 154 /* Debugging */
 155
 156 #if defined(LOCAL_DEBUG) || defined(GLOBAL_DEBUG)
 157 #define DBG(x, y...) debug(x, ##y)
 158 #else
 159 #define DBG(x, y...) do { } while(0)
 160 #endif
 161
 162 #ifdef DEBUGGING
 163 #define ASSERT(x) do { if (!(x)) bug("Assertion `%s' failed at %s:%d", #x, __FILE__, __LINE__); } while(0)
 164 #else
 165 #define ASSERT(x) do { } while(0)
 166 #endif
 167
 168 /* Pseudorandom numbers */
 169
 170 u32 random_u32(void);
 171
 172 #endif