urbit/include/c/defs.h

/* include/c/defs.h
**
** This file is in the public domain.
*/
  /** Loobeans - inverse booleans to match nock.
  **/
#     define c3y      0
#     define c3n      1

#     define _(x)        (c3y == (x))
#     define __(x)       ((x) ? c3y : c3n)
#     define c3a(x, y)   __(_(x) && _(y))
#     define c3o(x, y)   __(_(x) || _(y))


  /** Random useful C macros.
  **/
    /* Assert.  Good to capture.
    */
#     define c3_assert(x)                       \
        do {                                    \
          if (!(x)) {                           \
            fprintf(stderr,                     \
                    "\rAssertion '%s' failed "  \
                    "in %s:%d\n",               \
                    #x, __FILE__, __LINE__);    \
            c3_cooked();                        \
            assert(x);                          \
          }                                     \
        } while(0)

    /* Stub.
    */
#     define c3_stub       (assert(!"stub"), 0)

    /* Size in words.
    */
#     define c3_wiseof(x)  (((sizeof (x)) + 3) >> 2)

    /* Bit counting.
    */
#     define c3_bits_word(w) ((w) ? (32 - __builtin_clz(w)) : 0)

    /* Min and max.
    */
#     define c3_max(x, y) ( ((x) > (y)) ? (x) : (y) )
#     define c3_min(x, y) ( ((x) < (y)) ? (x) : (y) )

    /* Rotate.
    */
#     define c3_rotw(r, x)  ( ((x) << (r)) | ((x) >> (32 - (r))) )

    /* Emergency stdio fix.
    */
      int
      c3_cooked();

    /* Short integers.
    */
#     define c3_s1(a)          ( (a) )
#     define c3_s2(a, b)       ( ((b) << 8) | c3_s1(a) )
#     define c3_s3(a, b, c)    ( ((c) << 16) | c3_s2(a, b) )
#     define c3_s4(a, b, c, d) ( ((d) << 24) | c3_s3(a, b, c) )

#     define c3_s5(a, b, c, d, e) \
        ( ((uint64_t)c3_s1(e) << 32ULL) | c3_s4(a, b, c, d) )
#     define c3_s6(a, b, c, d, e, f) \
        ( ((uint64_t)c3_s2(e, f) << 32ULL) | c3_s4(a, b, c, d) )
#     define c3_s7(a, b, c, d, e, f, g) \
        ( ((uint64_t)c3_s3(e, f, g) << 32ULL) | c3_s4(a, b, c, d) )
#     define c3_s8(a, b, c, d, e, f, g, h) \
        ( ((uint64_t)c3_s4(e, f, g, h) << 32ULL) | c3_s4(a, b, c, d) )

    /* Byte-order twiddling.
    */
#     define c3_flip32(w) \
        ( (((w) >> 24) & 0xff) \
        | (((w) >> 16) & 0xff) << 8 \
        | (((w) >>  8) & 0xff) << 16 \
        | ( (w)        & 0xff) << 24 )

    /* Logging shorthand.
    */
#     define c3_log_every(n, args...) \
        do {                          \
          static c3_w cnt_w = 0;      \
                                      \
          if ( 0 == cnt_w % (n) ) {   \
            uL(fprintf(uH, args));    \
          }                           \
          cnt_w = (cnt_w + 1) % (n);  \
        } while (0)

    /* Asserting allocators.
    */
#     define c3_malloc(s) ({          \
        void* rut = malloc(s);        \
        if ( 0 == rut ) {             \
          c3_assert(!"memory lost");  \
        }                             \
        rut;})
#     define c3_calloc(s) ({          \
        void* rut = calloc(1,s);      \
        if ( 0 == rut ) {             \
          c3_assert(!"memory lost");  \
        }                             \
        rut;})
#     define c3_realloc(a, b) ({      \
        void* rut = realloc(a, b);    \
        if ( 0 == rut ) {             \
          c3_assert(!"memory lost");  \
        }                             \
        rut;})