/*
* User object handling.
* Copyright (c) 1998 New Generation Software (NGS) Oy
*
* Author: Markku Rossi
*/
/*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
* MA 02111-1307, USA
*/
/*
* $Source: /cygdrive/c/RCVS/CVS/ReactOS/reactos/lib/kjs/ksrc/object.c,v $
* $Id: object.c 21681 2006-04-21 15:00:24Z peterw $
*/
#include "ntddk.h"
#include "jsint.h"
#include "jsconfig.h"
/*
* Types and definitions.
*/
#define HASH_SIZE 128
/*
* Prototypes for static functions.
*/
static void hash_create (JSVirtualMachine *vm, JSObject *obj);
static void hash_insert (JSVirtualMachine *vm, JSObject *obj, const char *name,
unsigned int name_len, int pos);
static void hash_delete (JSVirtualMachine *vm, JSObject *obj, const char *name,
unsigned int name_len);
static int hash_lookup (JSObject *obj, char *name, unsigned int name_len);
/*
* Global functions.
*/
JSObject *
js_vm_object_new (JSVirtualMachine *vm)
{
JSObject *obj;
obj = js_vm_alloc (vm, sizeof (*obj));
obj->hash = NULL;
obj->num_props = 0;
obj->props = NULL;
return obj;
}
void
js_vm_object_mark (JSObject *obj)
{
int i;
unsigned int num_objects;
if (obj == NULL)
return;
tail_recursive:
if (!js_vm_mark_ptr (obj))
/* This object has already been marked. Nothing to do here. */
return;
js_vm_mark_ptr (obj->props);
/* Mark property hash. */
if (obj->hash)
{
JSObjectPropHashBucket *b;
int i;
js_vm_mark_ptr (obj->hash);
js_vm_mark_ptr (obj->hash_lengths);
for (i = 0; i < HASH_SIZE; i++)
for (b = obj->hash[i]; b; b = b->next)
{
js_vm_mark_ptr (b);
js_vm_mark_ptr (b->data);
}
}
/* Mark all non-object properties. */
num_objects = 0;
for (i = 0; i < obj->num_props; i++)
{
if (obj->props[i].value.type == JS_OBJECT)
{
if (!js_vm_is_marked_ptr (obj->props[i].value.u.vobject))
num_objects++;
}
else
js_vm_mark (&obj->props[i].value);
}
/* And finally, mark all objects we have left. */
if (num_objects > 0)
{
/* Find the objects. */
for (i = 0; i < obj->num_props; i++)
if (obj->props[i].value.type == JS_OBJECT
&& !js_vm_is_marked_ptr (obj->props[i].value.u.vobject))
{
if (num_objects == 1)
{
/*
* Hahaa, this is the only non-marked object. We can
* do a tail-recursion optimization.
*/
obj = obj->props[i].value.u.vobject;
goto tail_recursive;
}
/* Just mark it. */
js_vm_mark (&obj->props[i].value);
}
}
}
int
js_vm_object_load_property (JSVirtualMachine *vm, JSObject *obj,
JSSymbol prop, JSNode *value_return)
{
unsigned int ui;
JSSymbol link_sym = vm->syms.s___proto__;
JSObject *link_obj = NULL;
follow_link:
/* Check if we know this property. */
for (ui = 0; ui < obj->num_props; ui++)
if (obj->props[ui].name == prop)
{
JS_COPY (value_return, &obj->props[ui].value);
return JS_PROPERTY_FOUND;
}
else if (obj->props[ui].name == link_sym
&& obj->props[ui].value.type == JS_OBJECT)
link_obj = obj->props[ui].value.u.vobject;
/* Undefined so far. */
if (link_obj)
{
/* Follow the link. */
obj = link_obj;
link_obj = NULL;
goto follow_link;
}
/* Undefined. Make it undef. */
value_return->type = JS_UNDEFINED;
return JS_PROPERTY_UNKNOWN;
}
void
js_vm_object_store_property (JSVirtualMachine *vm, JSObject *obj,
JSSymbol prop, JSNode *val)
{
unsigned int ui;
JSSymbol free_slot = JS_SYMBOL_NULL;
/* Check if we already know this property. */
for (ui = 0; ui < obj->num_props; ui++)
if (obj->props[ui].name == prop)
{
JS_COPY (&obj->props[ui].value, val);
return;
}
else if (obj->props[ui].name == JS_SYMBOL_NULL)
free_slot = ui;
/* Must create a new property. */
if (free_slot == JS_SYMBOL_NULL)
{
/* Expand our array of properties. */
obj->props = js_vm_realloc (vm, obj->props,
(obj->num_props + 1) * sizeof (JSProperty));
free_slot = obj->num_props++;
}
obj->props[free_slot].name = prop;
obj->props[free_slot].attributes = 0;
JS_COPY (&obj->props[free_slot].value, val);
/* Insert it to the hash (if the hash has been created). */
if (obj->hash)
{
const char *name;
name = js_vm_symname (vm, prop);
hash_insert (vm, obj, name, strlen (name), free_slot);
}
}
void
js_vm_object_delete_property (JSVirtualMachine *vm, JSObject *obj,
JSSymbol prop)
{
unsigned int ui;
/* Check if we already know this property. */
for (ui = 0; ui < obj->num_props; ui++)
if (obj->props[ui].name == prop)
{
/* Found, remove it from our list of properties. */
obj->props[ui].name = JS_SYMBOL_NULL;
obj->props[ui].value.type = JS_UNDEFINED;
/* Remove its name from the hash (if present). */
if (obj->hash)
{
const char *name = js_vm_symname (vm, prop);
hash_delete (vm, obj, name, strlen (name));
}
/* All done here. */
return;
}
}
void
js_vm_object_load_array (JSVirtualMachine *vm, JSObject *obj, JSNode *sel,
JSNode *value_return)
{
if (sel->type == JS_INTEGER)
{
if (sel->u.vinteger < 0 || sel->u.vinteger >= obj->num_props)
value_return->type = JS_UNDEFINED;
else
JS_COPY (value_return, &obj->props[sel->u.vinteger].value);
}
else if (sel->type == JS_STRING)
{
int pos;
if (obj->hash == NULL)
hash_create (vm, obj);
pos = hash_lookup (obj, (char *) sel->u.vstring->data,
sel->u.vstring->len);
if (pos < 0)
value_return->type = JS_UNDEFINED;
else
JS_COPY (value_return, &obj->props[pos].value);
}
else
{
sprintf (vm->error, "load_property: illegal array index");
js_vm_error (vm);
}
}
void
js_vm_object_store_array (JSVirtualMachine *vm, JSObject *obj, JSNode *sel,
JSNode *value)
{
if (sel->type == JS_INTEGER)
{
if (sel->u.vinteger < 0)
{
sprintf (vm->error, "store_array: array index can't be nagative");
js_vm_error (vm);
}
if (sel->u.vinteger >= obj->num_props)
{
/* Expand properties. */
obj->props = js_vm_realloc (vm, obj->props,
(sel->u.vinteger + 1)
* sizeof (JSProperty));
/* Init the possible gap. */
for (; obj->num_props u.vinteger; obj->num_props++)
{
obj->props[obj->num_props].name = 0;
obj->props[obj->num_props].attributes = 0;
obj->props[obj->num_props].value.type = JS_UNDEFINED;
}
}
JS_COPY (&obj->props[sel->u.vinteger].value, value);
}
else if (sel->type == JS_STRING)
{
int pos;
if (obj->hash == NULL)
hash_create (vm, obj);
pos = hash_lookup (obj, (char *) sel->u.vstring->data,
sel->u.vstring->len);
if (pos < 0)
{
/* It is undefined, define it. */
obj->props = js_vm_realloc (vm, obj->props,
(obj->num_props + 1)
* sizeof (JSProperty));
/*
* XXX if is a valid symbol, intern it and set symbol's
* name below.
*/
obj->props[obj->num_props].name = JS_SYMBOL_NULL;
obj->props[obj->num_props].attributes = 0;
JS_COPY (&obj->props[obj->num_props].value, value);
hash_insert (vm, obj, (char *) sel->u.vstring->data,
sel->u.vstring->len, obj->num_props);
obj->num_props++;
}
else
JS_COPY (&obj->props[pos].value, value);
}
}
void
js_vm_object_delete_array (JSVirtualMachine *vm, JSObject *obj, JSNode *sel)
{
if (sel->type == JS_INTEGER)
{
if (0 u.vinteger && sel->u.vinteger < obj->num_props)
{
JSSymbol sym;
sym = obj->props[sel->u.vinteger].name;
obj->props[sel->u.vinteger].name = JS_SYMBOL_NULL;
obj->props[sel->u.vinteger].value.type = JS_UNDEFINED;
/* Remove its name from the hash (if present and it is not NULL). */
if (sym != JS_SYMBOL_NULL && obj->hash)
{
const char *name = js_vm_symname (vm, sym);
hash_delete (vm, obj, name, strlen (name));
}
}
}
else if (sel->type == JS_STRING)
{
int pos;
if (obj->hash == NULL)
hash_create (vm, obj);
pos = hash_lookup (obj, (char *) sel->u.vstring->data,
sel->u.vstring->len);
if (pos >= 0)
{
/* Found it. */
obj->props[pos].name = JS_SYMBOL_NULL;
obj->props[pos].value.type = JS_UNDEFINED;
/* And, delete its name from the hash. */
hash_delete (vm, obj, (char *) sel->u.vstring->data,
sel->u.vstring->len);
}
}
else
{
sprintf (vm->error, "delete_array: illegal array index");
js_vm_error (vm);
}
}
int
js_vm_object_nth (JSVirtualMachine *vm, JSObject *obj, int nth,
JSNode *value_return)
{
int i;
JSObjectPropHashBucket *b;
value_return->type = JS_UNDEFINED;
if (nth < 0)
return 0;
if (obj->hash == NULL)
hash_create (vm, obj);
for (i = 0; i < HASH_SIZE && nth >= obj->hash_lengths[i]; i++)
nth -= obj->hash_lengths[i];
if (i >= HASH_SIZE)
return 0;
/* The chain is the correct one. */
for (b = obj->hash[i]; b && nth > 0; b = b->next, nth--)
;
if (b == NULL)
{
char buf[512];
sprintf (buf,
"js_vm_object_nth(): chain didn't contain that many items%s",
JS_HOST_LINE_BREAK);
js_iostream_write (vm->s_stderr, buf, strlen (buf));
js_iostream_flush (vm->s_stderr);
abort ();
}
js_vm_make_string (vm, value_return, (char*)b->data, b->len);
return 1;
}
/*
* Static functions.
*/
static void
hash_create (JSVirtualMachine *vm, JSObject *obj)
{
int i;
obj->hash = js_vm_alloc (vm, HASH_SIZE * sizeof (JSObjectPropHashBucket *));
memset (obj->hash, 0, HASH_SIZE * sizeof (JSObjectPropHashBucket *));
obj->hash_lengths = js_vm_alloc (vm, HASH_SIZE * sizeof (unsigned int));
memset (obj->hash_lengths, 0, HASH_SIZE * sizeof (unsigned int));
/* Insert all known properties to the hash. */
for (i = 0; i < obj->num_props; i++)
if (obj->props[i].name != JS_SYMBOL_NULL)
{
const char *name;
name = js_vm_symname (vm, obj->props[i].name);
hash_insert (vm, obj, name, strlen (name), i);
}
}
static void
hash_insert (JSVirtualMachine *vm, JSObject *obj, const char *name,
unsigned int name_len, int pos)
{
unsigned int hash;
JSObjectPropHashBucket *b;
hash = js_count_hash (name, name_len) % HASH_SIZE;
for (b = obj->hash[hash]; b; b = b->next)
if (b->len == name_len
&& memcmp (b->data, name, name_len) == 0)
{
/* Ok, we already have a bucket */
b->value = pos;
return;
}
/* Create a new bucket. */
b = js_vm_alloc (vm, sizeof (*b));
b->len = name_len;
b->data = js_vm_alloc (vm, b->len);
memcpy (b->data, name, b->len);
b->value = pos;
b->next = obj->hash[hash];
obj->hash[hash] = b;
obj->hash_lengths[hash]++;
}
static void
hash_delete (JSVirtualMachine *vm, JSObject *obj, const char *name,
unsigned int name_len)
{
unsigned int hash;
JSObjectPropHashBucket *b, *prev;
hash = js_count_hash (name, name_len) % HASH_SIZE;
for (prev = NULL, b = obj->hash[hash]; b; prev = b, b = b->next)
if (b->len == name_len
&& memcmp (b->data, name, name_len) == 0)
{
/* Ok, found it. */
if (prev)
prev->next = b->next;
else
obj->hash[hash] = b->next;
obj->hash_lengths[hash]--;
break;
}
}
static int
hash_lookup (JSObject *obj, char *name, unsigned int name_len)
{
unsigned int hash;
JSObjectPropHashBucket *b;
hash = js_count_hash (name, name_len) % HASH_SIZE;
for (b = obj->hash[hash]; b; b = b->next)
if (b->len == name_len
&& memcmp (b->data, name, name_len) == 0)
return b->value;
return -1;
}
