C++ ERL_COUNT函数代码示例

ETERM *erl_mk_estring(const char *s, int len)
{
    ETERM *ep;
    int i;

    if ((!s) || (len < 0)) return NULL;

    /*
     * ASSERT(s != NULL);
     * ASSERT(len >= 0);
     */

    ep = erl_mk_empty_list();
    for (i = len-1; i >= 0; i--) {
	ETERM* integer;
	ETERM* cons;

	integer = erl_alloc_eterm(ERL_INTEGER);
	ERL_COUNT(integer) = 1;
	ERL_INT_VALUE(integer) = (unsigned char)s[i];

	cons = erl_alloc_eterm(ERL_LIST);
	ERL_COUNT(cons) = 1;
	HEAD(cons) = integer;
	TAIL(cons) = ep;
	ep = cons;
    }
    return ep;
}

/*
 * Create any kind of reference.
 */
ETERM *__erl_mk_reference (ETERM* t,
			   const char *node,
			   size_t len,
			   unsigned int n[],
			   unsigned int creation)
{
    if (t == NULL) {
	if (node == NULL) return NULL;
    
	t = erl_alloc_eterm(ERL_REF);
	ERL_COUNT(t) = 1;
    
	if (erl_atom_init_latin1(&t->uval.refval.node, node) == NULL)
	{	     
	    erl_free_term(t);
	    erl_errno = ENOMEM;
	    return NULL;
	}
    }
    ERL_REF_LEN(t) = len;
    ERL_REF_NUMBERS(t)[0]   = n[0] & 0x3ffff; /* 18 bits */
    ERL_REF_NUMBERS(t)[1]   = n[1];
    ERL_REF_NUMBERS(t)[2]   = n[2];
    ERL_REF_CREATION(t) = creation; /* 32 bits */

    return t;
}

/*
 * Create a FLOAT.
 */
ETERM *erl_mk_float (double d)
{
    ETERM *ep;

    ep = erl_alloc_eterm(ERL_FLOAT);
    ERL_COUNT(ep) = 1;
    ERL_FLOAT_VALUE(ep) = d;
    return ep;
}

/*
 * Extract the HEAD of a LIST. Bump the reference 
 * counter on the head object.
 */
ETERM *erl_hd (const ETERM *ep)
{
  if (!ep) return NULL;
  /* ASSERT(ep != NULL); */

    if (ERL_TYPE(ep) != ERL_LIST) {
	return (ETERM *) NULL; 
    }
    ERL_COUNT(ERL_CONS_HEAD(ep))++;
    return ERL_CONS_HEAD(ep);
}

/* 
 * Extract an ELEMENT from a TUPLE. Bump the 
 * reference counter on the extracted object.
 */
ETERM *erl_element (int ix, const ETERM *ep)
{
  if ((!ep) || (ix < 0)) return NULL;
  /*
   * ASSERT(ep != NULL);
   * ASSERT(ix >= 0);
   */

  if ((ERL_TYPE(ep) == ERL_TUPLE) &&  (ix <= ERL_TUPLE_SIZE(ep))) {
      ERL_COUNT(ERL_TUPLE_ELEMENT(ep, ix-1))++;
      return ERL_TUPLE_ELEMENT(ep, ix-1);
    }
    else 
	return NULL;
} /* erl_element */

int erl_setelement (int ix, ETERM *ep, ETERM *vp)
{
  if ((!ep) || (!vp)) return 0;
  /* ASSERT(ep != NULL);
   * ASSERT(vp != NULL);
   */

  if ((ERL_TYPE(ep) == ERL_TUPLE) && (ix <= ERL_TUPLE_SIZE(ep))) {
      erl_free_term(ERL_TUPLE_ELEMENT(ep, ix-1));
      ERL_TUPLE_ELEMENT(ep, ix-1) = vp;
      ERL_COUNT(vp)++;
      return 1;
  }  
  erl_err_msg("<ERROR> erl_setelement: Bad type to setelement or out of range \n");
  return 0;
}

/*
 * Create a FLOAT.
 */
ETERM *erl_mk_float (double d)
{
    ETERM *ep;

#if defined(HAVE_ISFINITE)
    /* Erlang does not handle Inf and NaN, so we return an error
     * rather than letting the Erlang VM complain about a bad external
     * term. */
    if(!isfinite(d)) {
        return NULL;
    }
#endif

    ep = erl_alloc_eterm(ERL_FLOAT);
    ERL_COUNT(ep) = 1;
    ERL_FLOAT_VALUE(ep) = d;
    return ep;
}

/* 
 * Return the CONTENT of a VARIABLE with NAME.
 * If the content is non-nil then bump its
 * reference counter.
 */
ETERM *erl_var_content (const ETERM *ep, const char *name)
{
  int i;
  ETERM *vp;

  if ((!ep) || (!name)) return NULL;
    
  /*   ASSERT(ep != NULL); */

  switch(ERL_TYPE(ep)) 
    {
    case ERL_VARIABLE:
	if (strcmp(ERL_VAR_NAME(ep), name) == 0) {
	    if ((vp = ERL_VAR_VALUE(ep)) != NULL) {
		ERL_COUNT(vp)++;
		return vp;
	    }
	}
	break;

    case ERL_LIST:
      while (ep && (ERL_TYPE(ep) != ERL_EMPTY_LIST)) {
	if ((vp = erl_var_content(HEAD(ep), name))) return vp;
	ep = TAIL(ep);
      }
      break;

    case ERL_TUPLE:
      for (i=0; i < ERL_TUPLE_SIZE(ep); i++) 
	  if ((vp = erl_var_content(ERL_TUPLE_ELEMENT(ep, i), name)))
	  {
	      return vp;
	  }
      break;
    
    default:
      /* variables can't occur in other types */
      break;
    }
    
  /* nothing found ! */
  return NULL;
}

ETERM *erl_iolist_to_binary (const ETERM* term)
{
    ETERM *dest;
    int size;
    char* ptr;

    if (!term) return NULL;
    /* ASSERT(term != NULL); */

    /*
     * Verify that the term is an I/O list and get its length.
     */

    size = erl_iolist_length(term);
    if (size == -1) {
	return NULL;
    }

    /*
     * Allocate the binary and copy the contents of the I/O list into it.
     */

    dest = erl_alloc_eterm(ERL_BINARY);
    ERL_COUNT(dest) = 1;
    ERL_BIN_SIZE(dest) = size;
    ptr = (char *)erl_malloc(size);
    ERL_BIN_PTR(dest) = (unsigned char *)ptr;
    iolist_to_buf(term, &ptr);

    /*
     * If ptr doesn't point exactly one byte beyond the end of the
     * binary, something must be seriously wrong.
     */

    if (ERL_BIN_PTR(dest) + size != (unsigned char *) ptr) return NULL;
    /* ASSERT(ERL_BIN_PTR(dest) + size == (unsigned char *) ptr); */

    return dest;
}

/*
 * Dump (print for debugging) a term. Useful if/when things go wrong.
 */
void
dump_term (FILE *fp, ETERM *t)
{
    if (fp == NULL) return;

    fprintf(fp, "#<%p ", t);

    if(t != NULL)
    {
	fprintf(fp, "count:%d, type:%d", ERL_COUNT(t), ERL_TYPE(t));

	switch(ERL_TYPE(t))
	{
	case ERL_UNDEF:
	    fprintf(fp, "==undef");
	    break;
	case ERL_INTEGER:
	    fprintf(fp, "==int, val:%d", ERL_INT_VALUE(t));
	    break;
	case ERL_U_INTEGER:
	    fprintf(fp, "==uint, val:%u", ERL_INT_UVALUE(t));
	    break;
	case ERL_FLOAT:
	    fprintf(fp, "==float, val:%g", ERL_FLOAT_VALUE(t));
	    break;
	case ERL_ATOM:
	    fprintf(fp, "==atom, name:%p \"%s\"", 
		    ERL_ATOM_PTR(t), ERL_ATOM_PTR(t));
	    break;
	case ERL_BINARY:
	    fprintf(fp, "==binary, data:%p,%u",
		    ERL_BIN_PTR(t), ERL_BIN_SIZE(t));
	    break;
	case ERL_PID:
	    fprintf(fp, "==pid, node:%p \"%s\"",
		    ERL_PID_NODE(t), ERL_PID_NODE(t));
	    break;
	case ERL_PORT:
	    fprintf(fp, "==port, node:%p \"%s\"",
		    ERL_PORT_NODE(t), ERL_PORT_NODE(t));
	    break;
	case ERL_REF:
	    fprintf(fp, "==ref, node:%p \"%s\"",
		    ERL_REF_NODE(t), ERL_REF_NODE(t));
	    break;
	case ERL_CONS:
	    fprintf(fp, "==cons");
	    fprintf(fp, ", car:");
	    dump_term(fp, ERL_CONS_HEAD(t));
	    fprintf(fp, ", cdr:");
	    dump_term(fp, ERL_CONS_TAIL(t));
	    break;
	case ERL_NIL:
	    fprintf(fp, "==nil");
	    break;
	case ERL_TUPLE:
	    fprintf(fp, "==tuple, elems:%p,%u", 
		    ERL_TUPLE_ELEMS(t), ERL_TUPLE_SIZE(t));
	    {
		size_t i;
		for(i = 0; i < ERL_TUPLE_SIZE(t); i++)
		{
		    fprintf(fp, "elem[%u]:", i);
		    dump_term(fp, ERL_TUPLE_ELEMENT(t, i));		    
		}
	    }
	    break;
	case ERL_VARIABLE:
	    fprintf(fp, "==variable, name:%p \"%s\"",
		    ERL_VAR_NAME(t), ERL_VAR_NAME(t));
	    fprintf(fp, ", value:");
	    dump_term(fp, ERL_VAR_VALUE(t));	    
	    break;

	default:
	    break;
	}
    }
    fprintf(fp, ">");
}

//.........这里部分代码省略.........
  erl_eterm_statistics(ulongp,ulongp);
  erl_free_array(etermpp,intx);
  erl_free_term(etermp);
  erl_free_compound(etermp);
  erl_malloc(longx);
  erl_free(voidp);

  erl_compare_ext(ucharp, ucharp);
  erl_decode(ucharp);
  erl_decode_buf(ucharpp);
  erl_encode(etermp,ucharp);
  erl_encode_buf(etermp,ucharpp);
  erl_ext_size(ucharp);
  erl_ext_type(ucharp);
  erl_peek_ext(ucharp,intx);
  erl_term_len(etermp);

  erl_gethostbyname(charp);
  erl_gethostbyaddr(charp, intx, intx);
  erl_gethostbyname_r(charp, hostp, charp, intx, intp);
  erl_gethostbyaddr_r(charp, intx, intx, hostp, charp, intx, intp);

  erl_init_resolve();
  erl_distversion(intx);

  erl_epmd_connect(inaddrp);
  erl_epmd_port(inaddrp, charp, intp);

  charp  = ERL_ATOM_PTR(etermp);
  intx   = ERL_ATOM_SIZE(etermp);
  ucharp = ERL_BIN_PTR(etermp);
  intx   = ERL_BIN_SIZE(etermp);
  etermp = ERL_CONS_HEAD(etermp);
  etermp = ERL_CONS_TAIL(etermp);
  intx   = ERL_COUNT(etermp);
  doublex= ERL_FLOAT_VALUE(etermp);
  uintx  = ERL_INT_UVALUE(etermp);
  intx   = ERL_INT_VALUE(etermp);
  intx   = ERL_IS_ATOM(etermp);
  intx   = ERL_IS_BINARY(etermp);
  intx   = ERL_IS_CONS(etermp);
  intx   = ERL_IS_EMPTY_LIST(etermp);
  intx   = ERL_IS_FLOAT(etermp);
  intx   = ERL_IS_INTEGER(etermp);
  intx   = ERL_IS_LIST(etermp);
  intx   = ERL_IS_PID(etermp);
  intx   = ERL_IS_PORT(etermp);
  intx   = ERL_IS_REF(etermp);
  intx   = ERL_IS_TUPLE(etermp);
  intx   = ERL_IS_UNSIGNED_INTEGER(etermp);
  uchar  = ERL_PID_CREATION(etermp);
  charp  = ERL_PID_NODE(etermp);
  uintx  = ERL_PID_NUMBER(etermp);
  uintx  = ERL_PID_SERIAL(etermp);
  uchar  = ERL_PORT_CREATION(etermp);
  charp  = ERL_PORT_NODE(etermp);
  uintx  = ERL_PORT_NUMBER(etermp);
  uchar  = ERL_REF_CREATION(etermp);
  intx   = ERL_REF_LEN(etermp);
  charp  = ERL_REF_NODE(etermp);
  uintx  = ERL_REF_NUMBER(etermp);
  uintp  = ERL_REF_NUMBERS(etermp);
  etermp = ERL_TUPLE_ELEMENT(etermp,intx);
  intx   = ERL_TUPLE_SIZE(etermp);

  return 
      BUFSIZ +
      EAGAIN +
      EHOSTUNREACH +
      EINVAL +
      EIO +
      EMSGSIZE +
      ENOMEM +
      ERL_ATOM +
      ERL_BINARY +
      ERL_ERROR +
      ERL_EXIT +
      ERL_FLOAT +
      ERL_INTEGER +
      ERL_LINK +
      ERL_LIST +
      ERL_MSG +
      ERL_NO_TIMEOUT +
      ERL_PID +
      ERL_PORT +
      ERL_REF +
      ERL_REG_SEND +
      ERL_SEND +
      ERL_SMALL_BIG +
      ERL_TICK +
      ERL_TIMEOUT +
      ERL_TUPLE +
      ERL_UNLINK +
      ERL_U_INTEGER +
      ERL_U_SMALL_BIG +
      ERL_VARIABLE +
      ETIMEDOUT +
      MAXNODELEN +
      MAXREGLEN;
}