/* $NetBSD: prop_number.c,v 1.11 2006/10/15 19:11:58 christos Exp $ */
/*-
* Copyright (c) 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <prop/prop_number.h>
#include "prop_object_impl.h"
#include "prop_rb_impl.h"
#if defined(_KERNEL)
#include <sys/systm.h>
#elif defined(_STANDALONE)
#include <sys/param.h>
#include <lib/libkern/libkern.h>
#else
#include <errno.h>
#include <stdlib.h>
#endif
struct _prop_number {
struct _prop_object pn_obj;
struct rb_node pn_link;
struct _prop_number_value pn_value;
};
#define RBNODE_TO_PN(n) \
((struct _prop_number *) \
((uintptr_t)n - offsetof(struct _prop_number, pn_link)))
_PROP_POOL_INIT(_prop_number_pool, sizeof(struct _prop_number), "propnmbr")
static void _prop_number_free(void *);
static boolean_t _prop_number_equals(void *, void *);
static const struct _prop_object_type _prop_object_type_number = {
.pot_type = PROP_TYPE_NUMBER,
.pot_free = _prop_number_free,
.pot_equals = _prop_number_equals,
};
#define prop_object_is_number(x) \
((x) != NULL && (x)->pn_obj.po_type == &_prop_object_type_number)
/*
* Number objects are immutable, and we are likely to have many number
* objects that have the same value. So, to save memory, we unique'ify
* numbers so we only have one copy of each.
*/
static int
_prop_number_compare_values(const struct _prop_number_value *pnv1,
const struct _prop_number_value *pnv2)
{
/* Signed numbers are sorted before unsigned numbers. */
if (pnv1->pnv_is_unsigned) {
if (! pnv2->pnv_is_unsigned)
return (1);
if (pnv1->pnv_unsigned < pnv2->pnv_unsigned)
return (-1);
if (pnv1->pnv_unsigned > pnv2->pnv_unsigned)
return (1);
return (0);
}
if (pnv2->pnv_is_unsigned)
return (-1);
if (pnv1->pnv_signed < pnv2->pnv_signed)
return (-1);
if (pnv1->pnv_signed > pnv2->pnv_signed)
return (1);
return (0);
}
static int
_prop_number_rb_compare_nodes(const struct rb_node *n1,
const struct rb_node *n2)
{
const prop_number_t pn1 = RBNODE_TO_PN(n1);
const prop_number_t pn2 = RBNODE_TO_PN(n2);
return (_prop_number_compare_values(&pn1->pn_value, &pn2->pn_value));
}
static int
_prop_number_rb_compare_key(const struct rb_node *n,
const void *v)
{
const prop_number_t pn = RBNODE_TO_PN(n);
const struct _prop_number_value *pnv = v;
return (_prop_number_compare_values(&pn->pn_value, pnv));
}
static const struct rb_tree_ops _prop_number_rb_tree_ops = {
.rbto_compare_nodes = _prop_number_rb_compare_nodes,
.rbto_compare_key = _prop_number_rb_compare_key,
};
static struct rb_tree _prop_number_tree;
static boolean_t _prop_number_tree_initialized;
_PROP_MUTEX_DECL_STATIC(_prop_number_tree_mutex)
static void
_prop_number_free(void *v)
{
prop_number_t pn = v;
_PROP_MUTEX_LOCK(_prop_number_tree_mutex);
_prop_rb_tree_remove_node(&_prop_number_tree, &pn->pn_link);
_PROP_MUTEX_UNLOCK(_prop_number_tree_mutex);
_PROP_POOL_PUT(_prop_number_pool, pn);
}
static boolean_t
_prop_number_equals(void *v1, void *v2)
{
prop_number_t num1 = v1;
prop_number_t num2 = v2;
if (! (prop_object_is_number(num1) &&
prop_object_is_number(num2)))
return (FALSE);
/*
* There is only ever one copy of a number object at any given
* time, so we can reduce this to a simple pointer equality check
* in the common case.
*/
if (num1 == num2)
return (TRUE);
/*
* If the numbers are the same signed-ness, then we know they
* cannot be equal because they would have had pointer equality.
*/
if (num1->pn_value.pnv_is_unsigned == num2->pn_value.pnv_is_unsigned)
return (FALSE);
/*
* We now have one signed value and one unsigned value. We can
* compare them iff:
* - The unsigned value is not larger than the signed value
* can represent.
* - The signed value is not smaller than the unsigned value
* can represent.
*/
if (num1->pn_value.pnv_is_unsigned) {
/*
* num1 is unsigned and num2 is signed.
*/
if (num1->pn_value.pnv_unsigned > INT64_MAX)
return (FALSE);
if (num2->pn_value.pnv_signed < 0)
return (FALSE);
} else {
/*
* num1 is signed and num2 is unsigned.
*/
if (num1->pn_value.pnv_signed < 0)
return (FALSE);
if (num2->pn_value.pnv_unsigned > INT64_MAX)
return (FALSE);
}
return (num1->pn_value.pnv_signed == num2->pn_value.pnv_signed);
}
prop_number_t
_prop_number_alloc(const struct _prop_number_value *pnv)
{
prop_number_t opn, pn;
struct rb_node *n;
/*
* Check to see if this already exists in the tree. If it does,
* we just retain it and return it.
*/
_PROP_MUTEX_LOCK(_prop_number_tree_mutex);
if (! _prop_number_tree_initialized) {
_prop_rb_tree_init(&_prop_number_tree,
&_prop_number_rb_tree_ops);
_prop_number_tree_initialized = TRUE;
} else {
n = _prop_rb_tree_find(&_prop_number_tree, pnv);
if (n != NULL) {
opn = RBNODE_TO_PN(n);
prop_object_retain(opn);
_PROP_MUTEX_UNLOCK(_prop_number_tree_mutex);
return (opn);
}
}
_PROP_MUTEX_UNLOCK(_prop_number_tree_mutex);
/*
* Not in the tree. Create it now.
*/
pn = _PROP_POOL_GET(_prop_number_pool);
if (pn == NULL)
return (NULL);
_prop_object_init(&pn->pn_obj, &_prop_object_type_number);
pn->pn_value = *pnv;
/*
* We dropped the mutex when we allocated the new object, so
* we have to check again if it is in the tree.
*/
_PROP_MUTEX_LOCK(_prop_number_tree_mutex);
n = _prop_rb_tree_find(&_prop_number_tree, pnv);
if (n != NULL) {
opn = RBNODE_TO_PN(n);
prop_object_retain(opn);
_PROP_MUTEX_UNLOCK(_prop_number_tree_mutex);
_PROP_POOL_PUT(_prop_number_pool, pn);
return (opn);
}
_prop_rb_tree_insert_node(&_prop_number_tree, &pn->pn_link);
_PROP_MUTEX_UNLOCK(_prop_number_tree_mutex);
return (pn);
}
/*
* prop_number_create_integer --
* Create a prop_number_t and initialize it with the
* provided integer value.
*/
prop_number_t
prop_number_create_integer(int64_t val)
{
struct _prop_number_value pnv;
memset(&pnv, 0, sizeof(pnv));
pnv.pnv_signed = val;
pnv.pnv_is_unsigned = FALSE;
return (_prop_number_alloc(&pnv));
}
/*
* prop_number_create_unsigned_integer --
* Create a prop_number_t and initialize it with the
* provided unsigned integer value.
*/
prop_number_t
prop_number_create_unsigned_integer(uint64_t val)
{
struct _prop_number_value pnv;
memset(&pnv, 0, sizeof(pnv));
pnv.pnv_unsigned = val;
pnv.pnv_is_unsigned = TRUE;
return (_prop_number_alloc(&pnv));
}
/*
* prop_number_copy --
* Copy a prop_number_t.
*/
prop_number_t
prop_number_copy(prop_number_t opn)
{
if (! prop_object_is_number(opn))
return (NULL);
/*
* Because we only ever allocate one object for any given
* value, this can be reduced to a simple retain operation.
*/
prop_object_retain(opn);
return (opn);
}
/*
* prop_number_unsigned --
* Returns TRUE if the prop_number_t has an unsigned value.
*/
boolean_t
prop_number_unsigned(prop_number_t pn)
{
return (pn->pn_value.pnv_is_unsigned);
}
/*
* prop_number_size --
* Return the size, in bits, required to hold the value of
* the specified number.
*/
int
prop_number_size(prop_number_t pn)
{
struct _prop_number_value *pnv;
if (! prop_object_is_number(pn))
return (0);
pnv = &pn->pn_value;
if (pnv->pnv_is_unsigned) {
if (pnv->pnv_unsigned > UINT32_MAX)
return (64);
if (pnv->pnv_unsigned > UINT16_MAX)
return (32);
if (pnv->pnv_unsigned > UINT8_MAX)
return (16);
return (8);
}
if (pnv->pnv_signed > INT32_MAX || pnv->pnv_signed < INT32_MIN)
return (64);
if (pnv->pnv_signed > INT16_MAX || pnv->pnv_signed < INT16_MIN)
return (32);
if (pnv->pnv_signed > INT8_MAX || pnv->pnv_signed < INT8_MIN)
return (16);
return (8);
}
/*
* prop_number_integer_value --
* Get the integer value of a prop_number_t.
*/
int64_t
prop_number_integer_value(prop_number_t pn)
{
/*
* XXX Impossible to distinguish between "not a prop_number_t"
* XXX and "prop_number_t has a value of 0".
*/
if (! prop_object_is_number(pn))
return (0);
return (pn->pn_value.pnv_signed);
}
/*
* prop_number_unsigned_integer_value --
* Get the unsigned integer value of a prop_number_t.
*/
uint64_t
prop_number_unsigned_integer_value(prop_number_t pn)
{
/*
* XXX Impossible to distinguish between "not a prop_number_t"
* XXX and "prop_number_t has a value of 0".
*/
if (! prop_object_is_number(pn))
return (0);
return (pn->pn_value.pnv_unsigned);
}
/*
* prop_number_equals --
* Return TRUE if two numbers are equivalent.
*/
boolean_t
prop_number_equals(prop_number_t num1, prop_number_t num2)
{
return (_prop_number_equals(num1, num2));
}
/*
* prop_number_equals_integer --
* Return TRUE if the number is equivalent to the specified integer.
*/
boolean_t
prop_number_equals_integer(prop_number_t pn, int64_t val)
{
if (! prop_object_is_number(pn))
return (FALSE);
if (pn->pn_value.pnv_is_unsigned &&
(pn->pn_value.pnv_unsigned > INT64_MAX || val < 0))
return (FALSE);
return (pn->pn_value.pnv_signed == val);
}
/*
* prop_number_equals_unsigned_integer --
* Return TRUE if the number is equivalent to the specified
* unsigned integer.
*/
boolean_t
prop_number_equals_unsigned_integer(prop_number_t pn, uint64_t val)
{
if (! prop_object_is_number(pn))
return (FALSE);
if (! pn->pn_value.pnv_is_unsigned &&
(pn->pn_value.pnv_signed < 0 || val > INT64_MAX))
return (FALSE);
return (pn->pn_value.pnv_unsigned == val);
}
