[p5sagit/p5-mst-13.2.git] / ext / Hash / Util / FieldHash / FieldHash.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

/* support for Hash::Util::FieldHash, prefix HUF_ */

/* The object registry, a package variable */
#define HUF_OB_REG "Hash::Util::FieldHash::ob_reg"
/* Magic cookies to recognize object id's.  Hi, Eva, David */
#define HUF_COOKIE 2805.1980
#define HUF_REFADDR_COOKIE 1811.1976


/* For global cache of object registry */
#define MY_CXT_KEY "Hash::Util::FieldHash::_guts" XS_VERSION
typedef struct {
    HV* ob_reg; /* Cache object registry */
} my_cxt_t;
START_MY_CXT

/* Deal with global context */
#define HUF_INIT 1
#define HUF_CLONE 0
#define HUF_RESET -1

void HUF_global(I32 how) {
    if (how == HUF_INIT) {
        MY_CXT_INIT;
        MY_CXT.ob_reg = get_hv(HUF_OB_REG, 1);
    } else if (how == HUF_CLONE) {
        MY_CXT_CLONE;
        MY_CXT.ob_reg = get_hv(HUF_OB_REG, 0);
    } else if (how == HUF_RESET) {
        dMY_CXT;
        MY_CXT.ob_reg = get_hv(HUF_OB_REG, 0);
    }
}

/* the id as an SV, optionally marked in the nv (unused feature) */
SV* HUF_id(SV* ref, NV cookie) {
    SV* id = sv_newmortal();
    if (cookie == 0 ) {
        SvUPGRADE(id, SVt_PVIV);
    } else {
        SvUPGRADE(id, SVt_PVNV);
        SvNV_set(id, cookie);
        SvNOK_on(id);
    }
    SvIV_set(id, PTR2UV(SvRV(ref)));
    SvIOK_on(id);
    return id;
}

/* plain id, only used for field hash entries in field lists */
SV* HUF_field_id(SV* obj) {
    return HUF_id(obj, 0.0);
}

/* object id (may be different in future) */
SV* HUF_obj_id(SV* obj) {
    return HUF_id(obj, 0.0);
}

/* set up uvar magic for any sv */
void HUF_add_uvar_magic(
    SV* sv,                    /* the sv to enchant, visible to * get/set */
    I32(* val)(pTHX_ IV, SV*), /* "get" function */
    I32(* set)(pTHX_ IV, SV*), /* "set" function */
    I32 index,                 /* get/set will see this */
    SV* thing                  /* any associated info */
) {
    struct ufuncs uf;
        uf.uf_val = val;
        uf.uf_set = set;
        uf.uf_index = index;
    sv_magic(sv, thing, PERL_MAGIC_uvar, (char*)&uf, sizeof(uf));
}

/* Fetch the data container of a trigger */
AV* HUF_get_trigger_content(SV* trigger) {
    MAGIC* mg;
    if (trigger && (mg = mg_find(trigger, PERL_MAGIC_uvar)))
        return (AV*)mg->mg_obj;
    return NULL;
}

/* Delete an object from all field hashes it may occur in.  Also delete
 * the object's entry from the object registry.  This function goes in
 * the uf_set field of the uvar magic of a trigger.
 */
I32 HUF_destroy_obj(pTHX_ IV index, SV* trigger) {
    /* Do nothing if the weakref wasn't undef'd.  Also don't bother
     * during global destruction.  (MY_CXT.ob_reg is sometimes funny there) */
    if (!SvROK(trigger) && (!PL_in_clean_all)) {
        dMY_CXT;
        AV* cont = HUF_get_trigger_content(trigger);
        SV* ob_id = *av_fetch(cont, 0, 0);
        HV* field_tab = (HV*) *av_fetch(cont, 1, 0);
        HE* ent;
        hv_iterinit(field_tab);
        while (ent = hv_iternext(field_tab)) {
            SV* field_ref = HeVAL(ent);
            SV* field = SvRV(field_ref);
            hv_delete_ent((HV*)field, ob_id, G_DISCARD, 0);
        }
        /* make it safe in case we must run in global clenaup, after all */
        if (PL_in_clean_all)
            HUF_global(HUF_RESET);
        hv_delete_ent(MY_CXT.ob_reg, ob_id, G_DISCARD, 0);
    }
    return 0;
}

/* Create a trigger for an object.  The trigger is a magical weak ref
 * that fires when the weak ref expires.  it holds the original id of
 * the object, and a list of field hashes from which the object may
 * have to be deleted.  The trigger is stored in the object registry
 * and also deleted when the object expires.
 */
SV* HUF_new_trigger(SV* obj, SV* ob_id) {
    dMY_CXT;
    SV* trigger = sv_rvweaken(newRV_inc(SvRV(obj)));
    AV* cont = newAV();
    sv_2mortal((SV*)cont);
    av_store(cont, 0, SvREFCNT_inc(ob_id));
    av_store(cont, 1, (SV*)newHV());
    HUF_add_uvar_magic(trigger, NULL, &HUF_destroy_obj, 0, (SV*)cont);
    hv_store_ent(MY_CXT.ob_reg, ob_id, trigger, 0);
    return trigger;
}

/* retrieve a trigger for obj if one exists, return NULL otherwise */
SV* HUF_ask_trigger(SV* ob_id) {
    dMY_CXT;
    HE* ent;
    if (ent = hv_fetch_ent(MY_CXT.ob_reg, ob_id, 0, 0))
        return HeVAL(ent);
    return NULL;
}

/* get the trigger for an object, creating it if necessary */
SV* HUF_get_trigger(SV* obj, SV* ob_id) {
    SV* trigger;
    if (!(trigger = HUF_ask_trigger(ob_id)))
        trigger = HUF_new_trigger(obj, ob_id);
    return trigger;
}

/* mark an object (trigger) as having been used with a field */
void HUF_mark_field(SV* trigger, SV* field) {
    AV* cont = HUF_get_trigger_content(trigger);
    HV* field_tab = (HV*) *av_fetch(cont, 1, 0);
    SV* field_ref = newRV_inc(field);
    SV* field_id = HUF_field_id(field_ref);
    hv_store_ent(field_tab, field_id, field_ref, 0);
}

#define HV_FETCH_ISSTORE   0x01
#define HV_FETCH_ISEXISTS  0x02
#define HV_FETCH_LVALUE    0x04
#define HV_FETCH_JUST_SV   0x08

#define HUF_WOULD_CREATE_KEY(x) ((x) != -1 && ((x) & (HV_FETCH_ISSTORE | HV_FETCH_LVALUE)))

/* The key exchange function.  It communicates with S_hv_magic_uvar_xkey
 * in hv.c */
I32 HUF_watch_key(pTHX_ IV action, SV* field) {
    MAGIC* mg = mg_find(field, PERL_MAGIC_uvar);
    SV* keysv = mg->mg_obj;
    if (keysv && SvROK(keysv)) {
        SV* ob_id = HUF_obj_id(keysv);
        mg->mg_obj = ob_id; /* key replacement */
        if (HUF_WOULD_CREATE_KEY(action)) {
            SV* trigger = HUF_get_trigger(keysv, ob_id);
            HUF_mark_field(trigger, field);
        }
    }
    return 0;
}

/* see if something is a field hash */
int HUF_get_status(HV* hash) {
    int ans = 0;
    if (hash && (SvTYPE(hash) == SVt_PVHV)) {
        MAGIC* mg;
        struct ufuncs* uf;
        ans = (mg = mg_find((SV*)hash, PERL_MAGIC_uvar)) &&
            (uf = (struct ufuncs *)mg->mg_ptr) &&
            (uf->uf_val == &HUF_watch_key) &&
            (uf->uf_set == NULL);
    }
    return ans;
}

/* Thread support.  These routines are called by CLONE (and nothing else) */

/* Fix entries for one object in all field hashes */
void HUF_fix_trigger(SV* trigger, SV* new_id) {
    AV* cont = HUF_get_trigger_content(trigger);
    HV* field_tab = (HV*) *av_fetch(cont, 1, 0);
    HV* new_tab = newHV();
    HE* ent;
    SV* old_id = *av_fetch(cont, 0, 0);
    hv_iterinit(field_tab);
    while (ent = hv_iternext(field_tab)) {
        SV* field_ref = HeVAL(ent);
        SV* field_id = HUF_field_id(field_ref);
        HV* field = (HV*)SvRV(field_ref);
        SV* val;
        /* recreate field tab entry */
        hv_store_ent(new_tab, field_id, SvREFCNT_inc(field_ref), 0);
        /* recreate field entry, if any */
        if (val = hv_delete_ent(field, old_id, 0, 0))
            hv_store_ent(field, new_id, SvREFCNT_inc(val), 0);
    }
    /* update the trigger */
    av_store(cont, 0, SvREFCNT_inc(new_id));
    av_store(cont, 1, (SV*)new_tab);
}

/* Go over object registry and fix all objects.  Also fix the object
 * registry.
 */
void HUF_fix_objects(void) {
    dMY_CXT;
    I32 i, len;
    HE* ent;
    AV* oblist = (AV*)sv_2mortal((SV*)newAV());
    hv_iterinit(MY_CXT.ob_reg);
    while(ent = hv_iternext(MY_CXT.ob_reg))
        av_push(oblist, SvREFCNT_inc(hv_iterkeysv(ent)));
    len = av_len(oblist);
    for (i = 0; i <= len; ++i) {
        SV* old_id = *av_fetch(oblist, i, 0);
        SV* trigger = hv_delete_ent(MY_CXT.ob_reg, old_id, 0, 0);
        SV* new_id = HUF_obj_id(trigger);
        HUF_fix_trigger(trigger, new_id);
        hv_store_ent(MY_CXT.ob_reg, new_id, SvREFCNT_inc(trigger), 0);
    }
}

/* test support (not needed for functionality) */

static SV* counter;
I32 HUF_inc_var(pTHX_ IV index, SV* which) {
    sv_setiv(counter, 1 + SvIV(counter));
    return 0;
}

MODULE = Hash::Util::FieldHash          PACKAGE = Hash::Util::FieldHash

BOOT:
{
    HUF_global(HUF_INIT); /* create variables */
}

int
_fieldhash(SV* href, int mode)
PROTOTYPE: $$
CODE:
    HV* field;
    RETVAL = 0;
    if (mode &&
        href && SvROK(href) &&
        (field = (HV*)SvRV(href)) &&
        SvTYPE(field) == SVt_PVHV
    ) {
        HUF_add_uvar_magic(
            SvRV(href),
            &HUF_watch_key,
            NULL,
            0,
            NULL
        );
        RETVAL = HUF_get_status(field);
    }
OUTPUT:
    RETVAL

void
CLONE(char* class)
CODE:
    if (0 == strcmp(class, "Hash::Util::FieldHash")) {
        HUF_global(HUF_CLONE);
        HUF_fix_objects();
    }

SV*
_get_obj_id(SV* obj)
CODE:
    RETVAL = NULL;
    if (SvROK(obj))
        RETVAL = HUF_obj_id(obj);
OUTPUT:
    RETVAL

void
_active_fields(SV* obj)
PPCODE:
    if (SvROK(obj)) {
        SV* ob_id = HUF_obj_id(obj);
        SV* trigger = HUF_ask_trigger(ob_id);
        if (trigger) {
            AV* cont = HUF_get_trigger_content(trigger);
            HV* field_tab = (HV*) *av_fetch(cont, 1, 0);
            HE* ent;
            hv_iterinit(field_tab);
            while (ent = hv_iternext(field_tab)) {
                HV* field = (HV*)SvRV(HeVAL(ent));
                if (hv_exists_ent(field, ob_id, 0))
                    XPUSHs(sv_2mortal(newRV_inc((SV*)field)));
            }
        }
    }

void
_test_uvar_get(SV* svref, SV* countref)
CODE:
    if (SvROK(svref) && SvROK(countref)) {
        counter = SvRV(countref);
        sv_setiv(counter, 0);
        HUF_add_uvar_magic(
            SvRV(svref),
            &HUF_inc_var,
            NULL,
            0,
            SvRV(countref)
        );
    }

void
_test_uvar_set(SV* svref, SV* countref)
CODE:
    if (SvROK(svref) && SvROK(countref)) {
        counter = SvRV(countref);
        sv_setiv(counter, 0);
        counter = SvRV(countref);
        HUF_add_uvar_magic(
            SvRV(svref),
            NULL,
            &HUF_inc_var,
            0,
            SvRV(countref)
        );
    }

void
_test_uvar_same(SV* svref, SV* countref)
CODE:
    if (SvROK(svref) && SvROK(countref)) {
        counter = SvRV(countref);
        sv_setiv(counter, 0);
        HUF_add_uvar_magic(
            SvRV(svref),
            &HUF_inc_var,
            &HUF_inc_var,
            0,
            NULL
        );
    }
Commit	Line	Data
1e73acc8	1	#include "EXTERN.h"
	2	#include "perl.h"
	3	#include "XSUB.h"
	4
	5	/* support for Hash::Util::FieldHash, prefix HUF_ */
	6
	7	/* The object registry, a package variable */
	8	#define HUF_OB_REG "Hash::Util::FieldHash::ob_reg"
	9	/* Magic cookies to recognize object id's. Hi, Eva, David */
	10	#define HUF_COOKIE 2805.1980
	11	#define HUF_REFADDR_COOKIE 1811.1976
	12
	13
	14	/* For global cache of object registry */
	15	#define MY_CXT_KEY "Hash::Util::FieldHash::_guts" XS_VERSION
	16	typedef struct {
	17	HV* ob_reg; /* Cache object registry */
	18	} my_cxt_t;
	19	START_MY_CXT
	20
	21	/* Deal with global context */
	22	#define HUF_INIT 1
	23	#define HUF_CLONE 0
	24	#define HUF_RESET -1
	25
	26	void HUF_global(I32 how) {
	27	if (how == HUF_INIT) {
	28	MY_CXT_INIT;
	29	MY_CXT.ob_reg = get_hv(HUF_OB_REG, 1);
	30	} else if (how == HUF_CLONE) {
	31	MY_CXT_CLONE;
	32	MY_CXT.ob_reg = get_hv(HUF_OB_REG, 0);
	33	} else if (how == HUF_RESET) {
	34	dMY_CXT;
	35	MY_CXT.ob_reg = get_hv(HUF_OB_REG, 0);
	36	}
	37	}
	38
	39	/* the id as an SV, optionally marked in the nv (unused feature) */
	40	SV* HUF_id(SV* ref, NV cookie) {
	41	SV* id = sv_newmortal();
	42	if (cookie == 0 ) {
	43	SvUPGRADE(id, SVt_PVIV);
	44	} else {
	45	SvUPGRADE(id, SVt_PVNV);
	46	SvNV_set(id, cookie);
	47	SvNOK_on(id);
	48	}
ce809d1f	49	SvIV_set(id, PTR2UV(SvRV(ref)));
1e73acc8	50	SvIOK_on(id);
	51	return id;
	52	}
	53
	54	/* plain id, only used for field hash entries in field lists */
	55	SV* HUF_field_id(SV* obj) {
	56	return HUF_id(obj, 0.0);
	57	}
	58
	59	/* object id (may be different in future) */
	60	SV* HUF_obj_id(SV* obj) {
	61	return HUF_id(obj, 0.0);
	62	}
	63
	64	/* set up uvar magic for any sv */
	65	void HUF_add_uvar_magic(
	66	SV* sv, /* the sv to enchant, visible to * get/set */
	67	I32(* val)(pTHX_ IV, SV), / "get" function */
	68	I32(* set)(pTHX_ IV, SV), / "set" function */
	69	I32 index, /* get/set will see this */
	70	SV* thing /* any associated info */
	71	) {
1e73acc8	72	struct ufuncs uf;
	73	uf.uf_val = val;
	74	uf.uf_set = set;
	75	uf.uf_index = index;
	76	sv_magic(sv, thing, PERL_MAGIC_uvar, (char*)&uf, sizeof(uf));
	77	}
	78
	79	/* Fetch the data container of a trigger */
	80	AV* HUF_get_trigger_content(SV* trigger) {
	81	MAGIC* mg;
	82	if (trigger && (mg = mg_find(trigger, PERL_MAGIC_uvar)))
	83	return (AV*)mg->mg_obj;
	84	return NULL;
	85	}
	86
	87	/* Delete an object from all field hashes it may occur in. Also delete
c418a2d4	88	* the object's entry from the object registry. This function goes in
c418a2d4	89	* the uf_set field of the uvar magic of a trigger.
1e73acc8	90	*/
	91	I32 HUF_destroy_obj(pTHX_ IV index, SV* trigger) {
	92	/* Do nothing if the weakref wasn't undef'd. Also don't bother
	93	* during global destruction. (MY_CXT.ob_reg is sometimes funny there) */
	94	if (!SvROK(trigger) && (!PL_in_clean_all)) {
	95	dMY_CXT;
	96	AV* cont = HUF_get_trigger_content(trigger);
	97	SV* ob_id = *av_fetch(cont, 0, 0);
	98	HV* field_tab = (HV) av_fetch(cont, 1, 0);
	99	HE* ent;
	100	hv_iterinit(field_tab);
	101	while (ent = hv_iternext(field_tab)) {
	102	SV* field_ref = HeVAL(ent);
	103	SV* field = SvRV(field_ref);
	104	hv_delete_ent((HV*)field, ob_id, G_DISCARD, 0);
	105	}
	106	/* make it safe in case we must run in global clenaup, after all */
	107	if (PL_in_clean_all)
	108	HUF_global(HUF_RESET);
	109	hv_delete_ent(MY_CXT.ob_reg, ob_id, G_DISCARD, 0);
	110	}
	111	return 0;
	112	}
	113
	114	/* Create a trigger for an object. The trigger is a magical weak ref
	115	* that fires when the weak ref expires. it holds the original id of
	116	* the object, and a list of field hashes from which the object may
	117	* have to be deleted. The trigger is stored in the object registry
	118	* and also deleted when the object expires.
	119	*/
	120	SV* HUF_new_trigger(SV* obj, SV* ob_id) {
	121	dMY_CXT;
	122	SV* trigger = sv_rvweaken(newRV_inc(SvRV(obj)));
	123	AV* cont = newAV();
	124	sv_2mortal((SV*)cont);
	125	av_store(cont, 0, SvREFCNT_inc(ob_id));
	126	av_store(cont, 1, (SV*)newHV());
	127	HUF_add_uvar_magic(trigger, NULL, &HUF_destroy_obj, 0, (SV*)cont);
	128	hv_store_ent(MY_CXT.ob_reg, ob_id, trigger, 0);
	129	return trigger;
	130	}
	131
	132	/* retrieve a trigger for obj if one exists, return NULL otherwise */
	133	SV* HUF_ask_trigger(SV* ob_id) {
	134	dMY_CXT;
	135	HE* ent;
	136	if (ent = hv_fetch_ent(MY_CXT.ob_reg, ob_id, 0, 0))
	137	return HeVAL(ent);
	138	return NULL;
	139	}
	140
	141	/* get the trigger for an object, creating it if necessary */
	142	SV* HUF_get_trigger(SV* obj, SV* ob_id) {
	143	SV* trigger;
	144	if (!(trigger = HUF_ask_trigger(ob_id)))
	145	trigger = HUF_new_trigger(obj, ob_id);
	146	return trigger;
	147	}
	148
	149	/* mark an object (trigger) as having been used with a field */
	150	void HUF_mark_field(SV* trigger, SV* field) {
	151	AV* cont = HUF_get_trigger_content(trigger);
	152	HV* field_tab = (HV) av_fetch(cont, 1, 0);
	153	SV* field_ref = newRV_inc(field);
154	SV* field_id = HUF_field_id(field_ref);
155	hv_store_ent(field_tab, field_id, field_ref, 0);
156	}
157
a607227a	158	#define HV_FETCH_ISSTORE 0x01
	159	#define HV_FETCH_ISEXISTS 0x02
	160	#define HV_FETCH_LVALUE 0x04
	161	#define HV_FETCH_JUST_SV 0x08
	162
	163	#define HUF_WOULD_CREATE_KEY(x) ((x) != -1 && ((x) & (HV_FETCH_ISSTORE \| HV_FETCH_LVALUE)))
	164
1e73acc8	165	/* The key exchange function. It communicates with S_hv_magic_uvar_xkey
1e73acc8	166	* in hv.c */
1748121c	167	I32 HUF_watch_key(pTHX_ IV action, SV* field) {
1e73acc8	168	MAGIC* mg = mg_find(field, PERL_MAGIC_uvar);
	169	SV* keysv = mg->mg_obj;
	170	if (keysv && SvROK(keysv)) {
	171	SV* ob_id = HUF_obj_id(keysv);
1e73acc8	172	mg->mg_obj = ob_id; /* key replacement */
a607227a	173	if (HUF_WOULD_CREATE_KEY(action)) {
	174	SV* trigger = HUF_get_trigger(keysv, ob_id);
	175	HUF_mark_field(trigger, field);
	176	}
1e73acc8	177	}
	178	return 0;
	179	}
	180
	181	/* see if something is a field hash */
	182	int HUF_get_status(HV* hash) {
	183	int ans = 0;
	184	if (hash && (SvTYPE(hash) == SVt_PVHV)) {
1e73acc8	185	MAGIC* mg;
	186	struct ufuncs* uf;
	187	ans = (mg = mg_find((SV*)hash, PERL_MAGIC_uvar)) &&
	188	(uf = (struct ufuncs *)mg->mg_ptr) &&
	189	(uf->uf_val == &HUF_watch_key) &&
	190	(uf->uf_set == NULL);
	191	}
	192	return ans;
	193	}
	194
	195	/* Thread support. These routines are called by CLONE (and nothing else) */
	196
	197	/* Fix entries for one object in all field hashes */
	198	void HUF_fix_trigger(SV* trigger, SV* new_id) {
	199	AV* cont = HUF_get_trigger_content(trigger);
	200	HV* field_tab = (HV) av_fetch(cont, 1, 0);
	201	HV* new_tab = newHV();
	202	HE* ent;
	203	SV* old_id = *av_fetch(cont, 0, 0);
	204	hv_iterinit(field_tab);
	205	while (ent = hv_iternext(field_tab)) {
	206	SV* field_ref = HeVAL(ent);
	207	SV* field_id = HUF_field_id(field_ref);
	208	HV* field = (HV*)SvRV(field_ref);
	209	SV* val;
	210	/* recreate field tab entry */
	211	hv_store_ent(new_tab, field_id, SvREFCNT_inc(field_ref), 0);
	212	/* recreate field entry, if any */
	213	if (val = hv_delete_ent(field, old_id, 0, 0))
	214	hv_store_ent(field, new_id, SvREFCNT_inc(val), 0);
	215	}
	216	/* update the trigger */
	217	av_store(cont, 0, SvREFCNT_inc(new_id));
	218	av_store(cont, 1, (SV*)new_tab);
	219	}
	220
	221	/* Go over object registry and fix all objects. Also fix the object
	222	* registry.
	223	*/
ce809d1f	224	void HUF_fix_objects(void) {
1e73acc8	225	dMY_CXT;
	226	I32 i, len;
	227	HE* ent;
	228	AV* oblist = (AV)sv_2mortal((SV)newAV());
	229	hv_iterinit(MY_CXT.ob_reg);
	230	while(ent = hv_iternext(MY_CXT.ob_reg))
	231	av_push(oblist, SvREFCNT_inc(hv_iterkeysv(ent)));
	232	len = av_len(oblist);
	233	for (i = 0; i <= len; ++i) {
	234	SV* old_id = *av_fetch(oblist, i, 0);
	235	SV* trigger = hv_delete_ent(MY_CXT.ob_reg, old_id, 0, 0);
	236	SV* new_id = HUF_obj_id(trigger);
	237	HUF_fix_trigger(trigger, new_id);
	238	hv_store_ent(MY_CXT.ob_reg, new_id, SvREFCNT_inc(trigger), 0);
	239	}
	240	}
	241
	242	/* test support (not needed for functionality) */
	243
	244	static SV* counter;
1748121c	245	I32 HUF_inc_var(pTHX_ IV index, SV* which) {
1e73acc8	246	sv_setiv(counter, 1 + SvIV(counter));
	247	return 0;
	248	}
	249
	250	MODULE = Hash::Util::FieldHash PACKAGE = Hash::Util::FieldHash
	251
	252	BOOT:
	253	{
	254	HUF_global(HUF_INIT); /* create variables */
	255	}
	256
	257	int
	258	_fieldhash(SV* href, int mode)
	259	PROTOTYPE: $$
	260	CODE:
	261	HV* field;
	262	RETVAL = 0;
	263	if (mode &&
	264	href && SvROK(href) &&
	265	(field = (HV*)SvRV(href)) &&
	266	SvTYPE(field) == SVt_PVHV
	267	) {
	268	HUF_add_uvar_magic(
	269	SvRV(href),
	270	&HUF_watch_key,
	271	NULL,
	272	0,
	273	NULL
	274	);
	275	RETVAL = HUF_get_status(field);
	276	}
	277	OUTPUT:
	278	RETVAL
	279
	280	void
	281	CLONE(char* class)
	282	CODE:
	283	if (0 == strcmp(class, "Hash::Util::FieldHash")) {
	284	HUF_global(HUF_CLONE);
	285	HUF_fix_objects();
	286	}
	287
	288	SV*
	289	_get_obj_id(SV* obj)
	290	CODE:
	291	RETVAL = NULL;
	292	if (SvROK(obj))
	293	RETVAL = HUF_obj_id(obj);
	294	OUTPUT:
	295	RETVAL
	296
c418a2d4	297	void
1e73acc8	298	_active_fields(SV* obj)
	299	PPCODE:
	300	if (SvROK(obj)) {
	301	SV* ob_id = HUF_obj_id(obj);
	302	SV* trigger = HUF_ask_trigger(ob_id);
	303	if (trigger) {
	304	AV* cont = HUF_get_trigger_content(trigger);
	305	HV* field_tab = (HV) av_fetch(cont, 1, 0);
	306	HE* ent;
	307	hv_iterinit(field_tab);
	308	while (ent = hv_iternext(field_tab)) {
	309	HV* field = (HV*)SvRV(HeVAL(ent));
	310	if (hv_exists_ent(field, ob_id, 0))
	311	XPUSHs(sv_2mortal(newRV_inc((SV*)field)));
	312	}
	313	}
	314	}
	315
	316	void
	317	_test_uvar_get(SV* svref, SV* countref)
	318	CODE:
	319	if (SvROK(svref) && SvROK(countref)) {
	320	counter = SvRV(countref);
	321	sv_setiv(counter, 0);
	322	HUF_add_uvar_magic(
	323	SvRV(svref),
	324	&HUF_inc_var,
	325	NULL,
	326	0,
	327	SvRV(countref)
	328	);
	329	}
	330
	331	void
	332	_test_uvar_set(SV* svref, SV* countref)
	333	CODE:
	334	if (SvROK(svref) && SvROK(countref)) {
	335	counter = SvRV(countref);
	336	sv_setiv(counter, 0);
	337	counter = SvRV(countref);
	338	HUF_add_uvar_magic(
	339	SvRV(svref),
	340	NULL,
	341	&HUF_inc_var,
	342	0,
	343	SvRV(countref)
	344	);
	345	}
	346
	347	void
	348	_test_uvar_same(SV* svref, SV* countref)
	349	CODE:
	350	if (SvROK(svref) && SvROK(countref)) {
	351	counter = SvRV(countref);
	352	sv_setiv(counter, 0);
	353	HUF_add_uvar_magic(
	354	SvRV(svref),
	355	&HUF_inc_var,
	356	&HUF_inc_var,
	357	0,
	358	NULL
	359	);
	360	}
	361