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 "sysdep/unix/timer.h"
  13 #include "lib/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 #define CALL(fn, args...) ({ if (fn) fn(args); })
  38
  39 static inline int uint_cmp(uint i1, uint i2)
  40 { return (int)(i1 > i2) - (int)(i1 < i2); }
  41
  42 static inline int u64_cmp(u64 i1, u64 i2)
  43 { return (int)(i1 > i2) - (int)(i1 < i2); }
  44
  45
  46 /* Bitfield macros */
  47
  48 /* b is u32 array (or ptr), l is size of it in bits (multiple of 32), p is 0..(l-1) */
  49 #define BIT32_VAL(p)            (((u32) 1) << ((p) % 32))
  50 #define BIT32_TEST(b,p)         ((b)[(p)/32] & BIT32_VAL(p))
  51 #define BIT32_SET(b,p)          ((b)[(p)/32] |= BIT32_VAL(p))
  52 #define BIT32_CLR(b,p)          ((b)[(p)/32] &= ~BIT32_VAL(p))
  53 #define BIT32_ZERO(b,l)         memset((b), 0, (l)/8)
  54
  55 #ifndef NULL
  56 #define NULL ((void *) 0)
  57 #endif
  58
  59
  60 /* Macros for gcc attributes */
  61
  62 #define NORET __attribute__((noreturn))
  63 #define UNUSED __attribute__((unused))
  64 #define PACKED __attribute__((packed))
  65
  66
  67 /* Microsecond time */
  68
  69 typedef s64 btime;
  70
  71 #define S_      *1000000
  72 #define MS_     *1000
  73 #define US_     *1
  74 #define TO_S    /1000000
  75 #define TO_MS   /1000
  76 #define TO_US   /1
  77
  78 #ifndef PARSER
  79 #define S       S_
  80 #define MS      MS_
  81 #define US      US_
  82 #endif
  83
  84
  85 /* Rate limiting */
  86
  87 struct tbf {
  88   bird_clock_t timestamp;               /* Last update */
  89   u16 count;                            /* Available tokens */
  90   u16 burst;                            /* Max number of tokens */
  91   u16 rate;                             /* Rate of replenishment */
  92   u16 mark;                             /* Whether last op was limited */
  93 };
  94
  95 /* Default TBF values for rate limiting log messages */
  96 #define TBF_DEFAULT_LOG_LIMITS { .rate = 1, .burst = 5 }
  97
  98 void tbf_update(struct tbf *f);
  99
 100 static inline int
 101 tbf_limit(struct tbf *f)
 102 {
 103   tbf_update(f);
 104
 105   if (!f->count)
 106   {
 107     f->mark = 1;
 108     return 1;
 109   }
 110
 111   f->count--;
 112   f->mark = 0;
 113   return 0;
 114 }
 115
 116
 117 /* Logging and dying */
 118
 119 typedef struct buffer {
 120   byte *start;
 121   byte *pos;
 122   byte *end;
 123 } buffer;
 124
 125 #define STACK_BUFFER_INIT(buf,size)             \
 126   do {                                          \
 127     buf.start = alloca(size);                   \
 128     buf.pos = buf.start;                        \
 129     buf.end = buf.start + size;                 \
 130   } while(0)
 131
 132 #define LOG_BUFFER_INIT(buf)                    \
 133   STACK_BUFFER_INIT(buf, LOG_BUFFER_SIZE)
 134
 135 #define LOG_BUFFER_SIZE 1024
 136
 137 #define log log_msg
 138 void log_commit(int class, buffer *buf);
 139 void log_msg(const char *msg, ...);
 140 void log_rl(struct tbf *rl, const char *msg, ...);
 141 void die(const char *msg, ...) NORET;
 142 void bug(const char *msg, ...) NORET;
 143
 144 #define L_DEBUG "\001"                  /* Debugging messages */
 145 #define L_TRACE "\002"                  /* Protocol tracing */
 146 #define L_INFO "\003"                   /* Informational messages */
 147 #define L_REMOTE "\004"                 /* Remote protocol errors */
 148 #define L_WARN "\005"                   /* Local warnings */
 149 #define L_ERR "\006"                    /* Local errors */
 150 #define L_AUTH "\007"                   /* Authorization failed etc. */
 151 #define L_FATAL "\010"                  /* Fatal errors */
 152 #define L_BUG "\011"                    /* BIRD bugs */
 153
 154 void debug(const char *msg, ...);               /* Printf to debug output */
 155
 156 /* Debugging */
 157
 158 #if defined(LOCAL_DEBUG) || defined(GLOBAL_DEBUG)
 159 #define DBG(x, y...) debug(x, ##y)
 160 #else
 161 #define DBG(x, y...) do { } while(0)
 162 #endif
 163
 164 #ifdef DEBUGGING
 165 #define ASSERT(x) do { if (!(x)) bug("Assertion `%s' failed at %s:%d", #x, __FILE__, __LINE__); } while(0)
 166 #else
 167 #define ASSERT(x) do { } while(0)
 168 #endif
 169
 170 /* Pseudorandom numbers */
 171
 172 u32 random_u32(void);
 173
 174 #endif