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 "lib/alloca.h"
  13
  14 /* Ugly structure offset handling macros */
  15
  16 struct align_probe { char x; long int y; };
  17
  18 #define OFFSETOF(s, i) ((size_t) &((s *)0)->i)
  19 #define SKIP_BACK(s, i, p) ((s *)((char *)p - OFFSETOF(s, i)))
  20 #define BIRD_ALIGN(s, a) (((s)+a-1)&~(a-1))
  21 #define CPU_STRUCT_ALIGN (sizeof(struct align_probe))
  22
  23 /* Utility macros */
  24
  25 #define MIN_(a,b) (((a)<(b))?(a):(b))
  26 #define MAX_(a,b) (((a)>(b))?(a):(b))
  27
  28 #ifndef PARSER
  29 #undef MIN
  30 #undef MAX
  31 #define MIN(a,b) MIN_(a,b)
  32 #define MAX(a,b) MAX_(a,b)
  33 #endif
  34
  35 #define U64(c) UINT64_C(c)
  36 #define ABS(a)   ((a)>=0 ? (a) : -(a))
  37 #define DELTA(a,b) (((a)>=(b))?(a)-(b):(b)-(a))
  38 #define ARRAY_SIZE(a) (sizeof(a)/sizeof(*(a)))
  39 #define BYTES(n) ((((uint) (n)) + 7) / 8)
  40 #define CALL(fn, args...) ({ if (fn) fn(args); })
  41 #define ADVANCE(w, r, l) ({ r -= (l); w += (l); })
  42
  43 static inline int uint_cmp(uint i1, uint i2)
  44 { return (int)(i1 > i2) - (int)(i1 < i2); }
  45
  46 static inline int u64_cmp(u64 i1, u64 i2)
  47 { return (int)(i1 > i2) - (int)(i1 < i2); }
  48
  49
  50 /* Bitfield macros */
  51
  52 /* b is u32 array (or ptr), l is size of it in bits (multiple of 32), p is 0..(l-1) */
  53 #define BIT32_VAL(p)            (((u32) 1) << ((p) % 32))
  54 #define BIT32_TEST(b,p)         ((b)[(p)/32] & BIT32_VAL(p))
  55 #define BIT32_SET(b,p)          ((b)[(p)/32] |= BIT32_VAL(p))
  56 #define BIT32_CLR(b,p)          ((b)[(p)/32] &= ~BIT32_VAL(p))
  57 #define BIT32_ZERO(b,l)         memset((b), 0, (l)/8)
  58
  59 /* The same, but counting bits from MSB */
  60 #define BIT32R_VAL(p)           ((((u32) 1) << 31) >> ((p) % 32))
  61 #define BIT32R_TEST(b,p)        ((b)[(p)/32] & BIT32R_VAL(p))
  62 #define BIT32R_SET(b,p)         ((b)[(p)/32] |= BIT32R_VAL(p))
  63 #define BIT32R_CLR(b,p)         ((b)[(p)/32] &= ~BIT32R_VAL(p))
  64 #define BIT32R_ZERO(b,l)        memset((b), 0, (l)/8)
  65
  66 #ifndef NULL
  67 #define NULL ((void *) 0)
  68 #endif
  69
  70 /* Macros for gcc attributes */
  71
  72 #define NORET __attribute__((noreturn))
  73 #define UNUSED __attribute__((unused))
  74 #define PACKED __attribute__((packed))
  75 #define NONNULL(...) __attribute__((nonnull((__VA_ARGS__))))
  76
  77 #ifndef HAVE_THREAD_LOCAL
  78 #define _Thread_local
  79 #endif
  80
  81 /* Microsecond time */
  82
  83 typedef s64 btime;
  84 //typedef s64 bird_clock_t;
  85
  86 #define S_      * (btime) 1000000
  87 #define MS_     * (btime) 1000
  88 #define US_     * (btime) 1
  89 #define TO_S    /1000000
  90 #define TO_MS   /1000
  91 #define TO_US   /1
  92
  93 #ifndef PARSER
  94 #define S       S_
  95 #define MS      MS_
  96 #define US      US_
  97 #define NS      /1000
  98 #endif
  99
 100 #define TIME_INFINITY ((s64) 0x7fffffffffffffff)
 101
 102
 103 /* Rate limiting */
 104
 105 struct tbf {
 106   btime timestamp;                      /* Last update */
 107   u64 count;                            /* Available micro-tokens */
 108   u16 burst;                            /* Max number of tokens */
 109   u16 rate;                             /* Rate of replenishment (tokens / sec) */
 110   u32 drop;                             /* Number of failed request since last successful */
 111 };
 112
 113 /* Default TBF values for rate limiting log messages */
 114 #define TBF_DEFAULT_LOG_LIMITS { .rate = 1, .burst = 5 }
 115
 116 int tbf_limit(struct tbf *f);
 117
 118
 119 /* Logging and dying */
 120
 121 typedef struct buffer {
 122   byte *start;
 123   byte *pos;
 124   byte *end;
 125 } buffer;
 126
 127 #define STACK_BUFFER_INIT(buf,size)             \
 128   do {                                          \
 129     buf.start = alloca(size);                   \
 130     buf.pos = buf.start;                        \
 131     buf.end = buf.start + size;                 \
 132   } while(0)
 133
 134 #define LOG_BUFFER_INIT(buf)                    \
 135   STACK_BUFFER_INIT(buf, LOG_BUFFER_SIZE)
 136
 137 #define LOG_BUFFER_SIZE 1024
 138
 139 #define log log_msg
 140 void log_commit(int class, buffer *buf);
 141 void log_msg(const char *msg, ...);
 142 void log_rl(struct tbf *rl, const char *msg, ...);
 143 void die(const char *msg, ...) NORET;
 144 void bug(const char *msg, ...) NORET;
 145
 146 #define L_DEBUG "\001"                  /* Debugging messages */
 147 #define L_TRACE "\002"                  /* Protocol tracing */
 148 #define L_INFO "\003"                   /* Informational messages */
 149 #define L_REMOTE "\004"                 /* Remote protocol errors */
 150 #define L_WARN "\005"                   /* Local warnings */
 151 #define L_ERR "\006"                    /* Local errors */
 152 #define L_AUTH "\007"                   /* Authorization failed etc. */
 153 #define L_FATAL "\010"                  /* Fatal errors */
 154 #define L_BUG "\011"                    /* BIRD bugs */
 155
 156 void debug(const char *msg, ...);       /* Printf to debug output */
 157
 158 /* Debugging */
 159
 160 #if defined(LOCAL_DEBUG) || defined(GLOBAL_DEBUG)
 161 #define DBG(x, y...) debug(x, ##y)
 162 #else
 163 #define DBG(x, y...) do { } while(0)
 164 #endif
 165
 166 #define ASSERT_DIE(x) do { if (!(x)) bug("Assertion '%s' failed at %s:%d", #x, __FILE__, __LINE__); } while(0)
 167
 168 #define EXPENSIVE_CHECK(x) /* intentionally left blank */
 169
 170 #ifdef DEBUGGING
 171 #define ASSERT(x) ASSERT_DIE(x)
 172 #define ASSUME(x) ASSERT_DIE(x)
 173 #ifdef ENABLE_EXPENSIVE_CHECKS
 174 #undef EXPENSIVE_CHECK
 175 #define EXPENSIVE_CHECK(x) ASSERT_DIE(x)
 176 #endif
 177 #else
 178 #define ASSERT(x) do { if (!(x)) log(L_BUG "Assertion '%s' failed at %s:%d", #x, __FILE__, __LINE__); } while(0)
 179 #define ASSUME(x) /* intentionally left blank */
 180 #endif
 181
 182
 183 #ifdef DEBUGGING
 184 asm(
 185     ".pushsection \".debug_gdb_scripts\", \"MS\",@progbits,1\n"
 186     ".byte 1\n" /* Python */
 187     ".asciz \"bird-gdb.py\"\n"
 188     ".popsection\n"
 189    );
 190 #endif
 191
 192 /* Pseudorandom numbers */
 193
 194 u32 random_u32(void);
 195
 196 #endif