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/***********************************************************************/
/* */
/* Objective Caml */
/* */
/* Damien Doligez, projet Para, INRIA Rocquencourt */
/* */
/* Copyright 1997 Institut National de Recherche en Informatique et */
/* en Automatique. All rights reserved. This file is distributed */
/* under the terms of the GNU Library General Public License, with */
/* the special exception on linking described in file ../LICENSE. */
/* */
/***********************************************************************/
/* $Id$ */
/* Operations on weak arrays */
#include <string.h>
#include "alloc.h"
#include "fail.h"
#include "memory.h"
#include "mlvalues.h"
value weak_list_head = 0;
static value weak_dummy = 0;
value weak_none = (value) &weak_dummy;
CAMLprim value weak_create (value len)
{
mlsize_t size, i;
value res;
size = Long_val (len) + 1;
if (size <= 0 || size > Max_wosize) invalid_argument ("Weak.create");
res = alloc_shr (size, Abstract_tag);
for (i = 1; i < size; i++) Field (res, i) = weak_none;
Field (res, 0) = weak_list_head;
weak_list_head = res;
return res;
}
#define None_val (Val_int(0))
#define Some_tag 0
CAMLprim value weak_set (value ar, value n, value el)
{
mlsize_t offset = Long_val (n) + 1;
Assert (Is_in_heap (ar));
if (offset < 1 || offset >= Wosize_val (ar)) invalid_argument ("Weak.set");
Field (ar, offset) = weak_none;
if (el != None_val){
value v; Assert (Wosize_val (el) == 1);
v = Field (el, 0);
if (Is_block (v) && (Is_young (v) || Is_in_heap (v))){
Modify (&Field (ar, offset), v);
}
}
return Val_unit;
}
#define Setup_for_gc
#define Restore_after_gc
CAMLprim value weak_get (value ar, value n)
{
CAMLparam2 (ar, n);
mlsize_t offset = Long_val (n) + 1;
CAMLlocal2 (res, elt);
Assert (Is_in_heap (ar));
if (offset < 1 || offset >= Wosize_val (ar)) invalid_argument ("Weak.get");
if (Field (ar, offset) == weak_none){
res = None_val;
}else{
elt = Field (ar, offset);
if (gc_phase == Phase_mark && Is_block (elt) && Is_in_heap (elt)){
darken (elt, NULL);
}
res = alloc_small (1, Some_tag);
Field (res, 0) = elt;
}
CAMLreturn (res);
}
#undef Setup_for_gc
#undef Restore_after_gc
CAMLprim value weak_get_copy (value ar, value n)
{
CAMLparam2 (ar, n);
mlsize_t offset = Long_val (n) + 1;
CAMLlocal2 (res, elt);
value v; /* Caution: this is NOT a local root. */
Assert (Is_in_heap (ar));
if (offset < 1 || offset >= Wosize_val (ar)) invalid_argument ("Weak.get");
v = Field (ar, offset);
if (v == weak_none) CAMLreturn (None_val);
if (Is_block (v) && (Is_young (v) || Is_in_heap (v))){
elt = alloc (Wosize_val (v), Tag_val (v)); /* The GC may erase or move v. */
v = Field (ar, offset);
if (v == weak_none) CAMLreturn (None_val);
if (Tag_val (v) < No_scan_tag){
mlsize_t i;
for (i = 0; i < Wosize_val (v); i++){
Modify (&Field (elt, i), Field (v, i));
}
}else{
memmove (Bp_val (elt), Bp_val (v), Bosize_val (v));
}
}else{
elt = v;
}
res = alloc_small (1, Some_tag);
Field (res, 0) = elt;
CAMLreturn (res);
}
CAMLprim value weak_check (value ar, value n)
{
mlsize_t offset = Long_val (n) + 1;
Assert (Is_in_heap (ar));
if (offset < 1 || offset >= Wosize_val (ar)) invalid_argument ("Weak.get");
return Val_bool (Field (ar, offset) != weak_none);
}
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