[p5sagit/p5-mst-13.2.git] / universal.c

#include "EXTERN.h"
#define PERL_IN_UNIVERSAL_C
#include "perl.h"

/*
 * Contributed by Graham Barr  <Graham.Barr@tiuk.ti.com>
 * The main guts of traverse_isa was actually copied from gv_fetchmeth
 */

STATIC SV *
S_isa_lookup(pTHX_ HV *stash, const char *name, int len, int level)
{
    AV* av;
    GV* gv;
    GV** gvp;
    HV* hv = Nullhv;
    SV* subgen = Nullsv;

    if (!stash)
	return &PL_sv_undef;

    if (strEQ(HvNAME(stash), name))
	return &PL_sv_yes;

    if (level > 100)
	Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
		   HvNAME(stash));

    gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);

    if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (subgen = GvSV(gv))
	&& (hv = GvHV(gv)))
    {
	if (SvIV(subgen) == PL_sub_generation) {
	    SV* sv;
	    SV** svp = (SV**)hv_fetch(hv, name, len, FALSE);
	    if (svp && (sv = *svp) != (SV*)&PL_sv_undef) {
	        DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
				  name, HvNAME(stash)) );
		return sv;
	    }
	}
	else {
	    DEBUG_o( Perl_deb(aTHX_ "ISA Cache in package %s is stale\n",
			      HvNAME(stash)) );
	    hv_clear(hv);
	    sv_setiv(subgen, PL_sub_generation);
	}
    }

    gvp = (GV**)hv_fetch(stash,"ISA",3,FALSE);

    if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (av = GvAV(gv))) {
	if (!hv || !subgen) {
	    gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, TRUE);

	    gv = *gvp;

	    if (SvTYPE(gv) != SVt_PVGV)
		gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);

	    if (!hv)
		hv = GvHVn(gv);
	    if (!subgen) {
		subgen = newSViv(PL_sub_generation);
		GvSV(gv) = subgen;
	    }
	}
	if (hv) {
	    SV** svp = AvARRAY(av);
	    /* NOTE: No support for tied ISA */
	    I32 items = AvFILLp(av) + 1;
	    while (items--) {
		SV* sv = *svp++;
		HV* basestash = gv_stashsv(sv, FALSE);
		if (!basestash) {
		    if (ckWARN(WARN_MISC))
			Perl_warner(aTHX_ WARN_SYNTAX,
		             "Can't locate package %s for @%s::ISA",
			    SvPVX(sv), HvNAME(stash));
		    continue;
		}
		if (&PL_sv_yes == isa_lookup(basestash, name, len, level + 1)) {
		    (void)hv_store(hv,name,len,&PL_sv_yes,0);
		    return &PL_sv_yes;
		}
	    }
	    (void)hv_store(hv,name,len,&PL_sv_no,0);
	}
    }

    return boolSV(strEQ(name, "UNIVERSAL"));
}

/*
=for apidoc sv_derived_from

Returns a boolean indicating whether the SV is derived from the specified
class.  This is the function that implements C<UNIVERSAL::isa>.  It works
for class names as well as for objects.

=cut
*/

bool
Perl_sv_derived_from(pTHX_ SV *sv, const char *name)
{
    char *type;
    HV *stash;

    stash = Nullhv;
    type = Nullch;

    if (SvGMAGICAL(sv))
        mg_get(sv) ;

    if (SvROK(sv)) {
        sv = SvRV(sv);
        type = sv_reftype(sv,0);
        if (SvOBJECT(sv))
            stash = SvSTASH(sv);
    }
    else {
        stash = gv_stashsv(sv, FALSE);
    }

    return (type && strEQ(type,name)) ||
            (stash && isa_lookup(stash, name, strlen(name), 0) == &PL_sv_yes)
        ? TRUE
        : FALSE ;
}

void XS_UNIVERSAL_isa(pTHXo_ CV *cv);
void XS_UNIVERSAL_can(pTHXo_ CV *cv);
void XS_UNIVERSAL_VERSION(pTHXo_ CV *cv);

void
Perl_boot_core_UNIVERSAL(pTHX)
{
    char *file = __FILE__;

    newXS("UNIVERSAL::isa",             XS_UNIVERSAL_isa,         file);
    newXS("UNIVERSAL::can",             XS_UNIVERSAL_can,         file);
    newXS("UNIVERSAL::VERSION", 	XS_UNIVERSAL_VERSION, 	  file);
}

#include "XSUB.h"

XS(XS_UNIVERSAL_isa)
{
    dXSARGS;
    SV *sv;
    char *name;
    STRLEN n_a;

    if (items != 2)
	Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");

    sv = ST(0);

    if (SvGMAGICAL(sv))
	mg_get(sv);

    if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))))
	XSRETURN_UNDEF;

    name = (char *)SvPV(ST(1),n_a);

    ST(0) = boolSV(sv_derived_from(sv, name));
    XSRETURN(1);
}

XS(XS_UNIVERSAL_can)
{
    dXSARGS;
    SV   *sv;
    char *name;
    SV   *rv;
    HV   *pkg = NULL;
    STRLEN n_a;

    if (items != 2)
	Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");

    sv = ST(0);

    if (SvGMAGICAL(sv))
	mg_get(sv);

    if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))))
	XSRETURN_UNDEF;

    name = (char *)SvPV(ST(1),n_a);
    rv = &PL_sv_undef;

    if (SvROK(sv)) {
        sv = (SV*)SvRV(sv);
        if (SvOBJECT(sv))
            pkg = SvSTASH(sv);
    }
    else {
        pkg = gv_stashsv(sv, FALSE);
    }

    if (pkg) {
        GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
        if (gv && isGV(gv))
	    rv = sv_2mortal(newRV((SV*)GvCV(gv)));
    }

    ST(0) = rv;
    XSRETURN(1);
}

XS(XS_UNIVERSAL_VERSION)
{
    dXSARGS;
    HV *pkg;
    GV **gvp;
    GV *gv;
    SV *sv;
    char *undef;

    if (SvROK(ST(0))) {
        sv = (SV*)SvRV(ST(0));
        if (!SvOBJECT(sv))
            Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
        pkg = SvSTASH(sv);
    }
    else {
        pkg = gv_stashsv(ST(0), FALSE);
    }

    gvp = pkg ? (GV**)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV**);

    if (gvp && isGV(gv = *gvp) && SvOK(sv = GvSV(gv))) {
        SV *nsv = sv_newmortal();
        sv_setsv(nsv, sv);
        sv = nsv;
        undef = Nullch;
    }
    else {
        sv = (SV*)&PL_sv_undef;
        undef = "(undef)";
    }

    if (items > 1) {
	STRLEN len;
	SV *req = ST(1);

	if (undef)
	    Perl_croak(aTHX_ "%s does not define $%s::VERSION--version check failed",
		       HvNAME(pkg), HvNAME(pkg));

	if (!SvNIOK(sv) && SvPOK(sv)) {
	    char *str = SvPVx(sv,len);
	    while (len) {
		--len;
		/* XXX could DWIM "1.2.3" here */
		if (!isDIGIT(str[len]) && str[len] != '.' && str[len] != '_')
		    break;
	    }
	    if (len) {
		if (SvNOK(req) && SvPOK(req)) {
		    /* they said C<use Foo v1.2.3> and $Foo::VERSION
		     * doesn't look like a float: do string compare */
		    if (sv_cmp(req,sv) == 1) {
			Perl_croak(aTHX_ "%s v%"VDf" required--"
				   "this is only v%"VDf,
				   HvNAME(pkg), req, sv);
		    }
		    goto finish;
		}
		/* they said C<use Foo 1.002_003> and $Foo::VERSION
		 * doesn't look like a float: force numeric compare */
		(void)SvUPGRADE(sv, SVt_PVNV);
		SvNVX(sv) = str_to_version(sv);
		SvPOK_off(sv);
		SvNOK_on(sv);
	    }
	}
	/* if we get here, we're looking for a numeric comparison,
	 * so force the required version into a float, even if they
	 * said C<use Foo v1.2.3> */
	if (SvNOK(req) && SvPOK(req)) {
	    NV n = SvNV(req);
	    req = sv_newmortal();
	    sv_setnv(req, n);
	}

	if (SvNV(req) > SvNV(sv))
	    Perl_croak(aTHX_ "%s version %s required--this is only version %s",
		  HvNAME(pkg), SvPV(req,len), SvPV(sv,len));
    }

finish:
    ST(0) = sv;

    XSRETURN(1);
}
Commit	Line	Data
6d4a7be2	1	#include "EXTERN.h"
864dbfa3	2	#define PERL_IN_UNIVERSAL_C
6d4a7be2	3	#include "perl.h"
6d4a7be2	4
	5	/*
	6	* Contributed by Graham Barr <Graham.Barr@tiuk.ti.com>
	7	* The main guts of traverse_isa was actually copied from gv_fetchmeth
	8	*/
	9
76e3520e	10	STATIC SV *
cea2e8a9	11	S_isa_lookup(pTHX_ HV stash, const char name, int len, int level)
6d4a7be2	12	{
	13	AV* av;
	14	GV* gv;
	15	GV** gvp;
	16	HV* hv = Nullhv;
46e4b22b	17	SV* subgen = Nullsv;
6d4a7be2	18
6d4a7be2	19	if (!stash)
3280af22	20	return &PL_sv_undef;
6d4a7be2	21
46e4b22b	22	if (strEQ(HvNAME(stash), name))
3280af22	23	return &PL_sv_yes;
6d4a7be2	24
6d4a7be2	25	if (level > 100)
46e4b22b	26	Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
46e4b22b	27	HvNAME(stash));
6d4a7be2	28
	29	gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);
	30
46e4b22b	31	if (gvp && (gv = gvp) != (GV)&PL_sv_undef && (subgen = GvSV(gv))
	32	&& (hv = GvHV(gv)))
	33	{
	34	if (SvIV(subgen) == PL_sub_generation) {
	35	SV* sv;
	36	SV svp = (SV)hv_fetch(hv, name, len, FALSE);
	37	if (svp && (sv = svp) != (SV)&PL_sv_undef) {
	38	DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
	39	name, HvNAME(stash)) );
	40	return sv;
	41	}
	42	}
	43	else {
	44	DEBUG_o( Perl_deb(aTHX_ "ISA Cache in package %s is stale\n",
	45	HvNAME(stash)) );
	46	hv_clear(hv);
	47	sv_setiv(subgen, PL_sub_generation);
	48	}
6d4a7be2	49	}
	50
	51	gvp = (GV**)hv_fetch(stash,"ISA",3,FALSE);
46e4b22b	52
3280af22	53	if (gvp && (gv = gvp) != (GV)&PL_sv_undef && (av = GvAV(gv))) {
46e4b22b	54	if (!hv \|\| !subgen) {
6d4a7be2	55	gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, TRUE);
	56
	57	gv = *gvp;
	58
	59	if (SvTYPE(gv) != SVt_PVGV)
	60	gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
	61
46e4b22b	62	if (!hv)
	63	hv = GvHVn(gv);
	64	if (!subgen) {
	65	subgen = newSViv(PL_sub_generation);
	66	GvSV(gv) = subgen;
	67	}
6d4a7be2	68	}
46e4b22b	69	if (hv) {
6d4a7be2	70	SV** svp = AvARRAY(av);
93965878	71	/* NOTE: No support for tied ISA */
93965878	72	I32 items = AvFILLp(av) + 1;
6d4a7be2	73	while (items--) {
	74	SV* sv = *svp++;
	75	HV* basestash = gv_stashsv(sv, FALSE);
	76	if (!basestash) {
599cee73	77	if (ckWARN(WARN_MISC))
cea2e8a9	78	Perl_warner(aTHX_ WARN_SYNTAX,
599cee73	79	"Can't locate package %s for @%s::ISA",
6d4a7be2	80	SvPVX(sv), HvNAME(stash));
	81	continue;
	82	}
46e4b22b	83	if (&PL_sv_yes == isa_lookup(basestash, name, len, level + 1)) {
3280af22	84	(void)hv_store(hv,name,len,&PL_sv_yes,0);
3280af22	85	return &PL_sv_yes;
6d4a7be2	86	}
6d4a7be2	87	}
3280af22	88	(void)hv_store(hv,name,len,&PL_sv_no,0);
6d4a7be2	89	}
	90	}
	91
e09f3e01	92	return boolSV(strEQ(name, "UNIVERSAL"));
6d4a7be2	93	}
6d4a7be2	94
954c1994	95	/*
	96	=for apidoc sv_derived_from
	97
	98	Returns a boolean indicating whether the SV is derived from the specified
	99	class. This is the function that implements C<UNIVERSAL::isa>. It works
	100	for class names as well as for objects.
	101
	102	=cut
	103	*/
	104
55497cff	105	bool
864dbfa3	106	Perl_sv_derived_from(pTHX_ SV sv, const char name)
55497cff	107	{
55497cff	108	char *type;
55497cff	109	HV *stash;
46e4b22b	110
55497cff	111	stash = Nullhv;
55497cff	112	type = Nullch;
46e4b22b	113
55497cff	114	if (SvGMAGICAL(sv))
	115	mg_get(sv) ;
	116
	117	if (SvROK(sv)) {
	118	sv = SvRV(sv);
	119	type = sv_reftype(sv,0);
46e4b22b	120	if (SvOBJECT(sv))
55497cff	121	stash = SvSTASH(sv);
	122	}
	123	else {
	124	stash = gv_stashsv(sv, FALSE);
	125	}
46e4b22b	126
55497cff	127	return (type && strEQ(type,name)) \|\|
3280af22	128	(stash && isa_lookup(stash, name, strlen(name), 0) == &PL_sv_yes)
55497cff	129	? TRUE
55497cff	130	: FALSE ;
55497cff	131	}
55497cff	132
0cb96387	133	void XS_UNIVERSAL_isa(pTHXo_ CV *cv);
	134	void XS_UNIVERSAL_can(pTHXo_ CV *cv);
	135	void XS_UNIVERSAL_VERSION(pTHXo_ CV *cv);
	136
	137	void
	138	Perl_boot_core_UNIVERSAL(pTHX)
	139	{
	140	char *file = __FILE__;
	141
	142	newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
	143	newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
	144	newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
	145	}
	146
76e3520e	147	#include "XSUB.h"
55497cff	148
6d4a7be2	149	XS(XS_UNIVERSAL_isa)
	150	{
	151	dXSARGS;
55497cff	152	SV *sv;
55497cff	153	char *name;
2d8e6c8d	154	STRLEN n_a;
6d4a7be2	155
6d4a7be2	156	if (items != 2)
cea2e8a9	157	Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
6d4a7be2	158
6d4a7be2	159	sv = ST(0);
f8f70380	160
d3f7f2b2	161	if (SvGMAGICAL(sv))
	162	mg_get(sv);
	163
aca069ec	164	if (!SvOK(sv) \|\| !(SvROK(sv) \|\| (SvPOK(sv) && SvCUR(sv))))
f8f70380	165	XSRETURN_UNDEF;
f8f70380	166
2d8e6c8d	167	name = (char *)SvPV(ST(1),n_a);
6d4a7be2	168
54310121	169	ST(0) = boolSV(sv_derived_from(sv, name));
6d4a7be2	170	XSRETURN(1);
	171	}
	172
6d4a7be2	173	XS(XS_UNIVERSAL_can)
	174	{
	175	dXSARGS;
	176	SV *sv;
	177	char *name;
	178	SV *rv;
6f08146e	179	HV *pkg = NULL;
2d8e6c8d	180	STRLEN n_a;
6d4a7be2	181
6d4a7be2	182	if (items != 2)
cea2e8a9	183	Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
6d4a7be2	184
6d4a7be2	185	sv = ST(0);
f8f70380	186
d3f7f2b2	187	if (SvGMAGICAL(sv))
	188	mg_get(sv);
	189
aca069ec	190	if (!SvOK(sv) \|\| !(SvROK(sv) \|\| (SvPOK(sv) && SvCUR(sv))))
f8f70380	191	XSRETURN_UNDEF;
f8f70380	192
2d8e6c8d	193	name = (char *)SvPV(ST(1),n_a);
3280af22	194	rv = &PL_sv_undef;
6d4a7be2	195
46e4b22b	196	if (SvROK(sv)) {
6f08146e	197	sv = (SV*)SvRV(sv);
46e4b22b	198	if (SvOBJECT(sv))
6f08146e	199	pkg = SvSTASH(sv);
	200	}
	201	else {
	202	pkg = gv_stashsv(sv, FALSE);
	203	}
	204
	205	if (pkg) {
dc848c6f	206	GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
	207	if (gv && isGV(gv))
	208	rv = sv_2mortal(newRV((SV*)GvCV(gv)));
6d4a7be2	209	}
	210
	211	ST(0) = rv;
	212	XSRETURN(1);
	213	}
	214
6d4a7be2	215	XS(XS_UNIVERSAL_VERSION)
	216	{
	217	dXSARGS;
	218	HV *pkg;
	219	GV **gvp;
	220	GV *gv;
	221	SV *sv;
	222	char *undef;
	223
1571675a	224	if (SvROK(ST(0))) {
6d4a7be2	225	sv = (SV*)SvRV(ST(0));
1571675a	226	if (!SvOBJECT(sv))
cea2e8a9	227	Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
6d4a7be2	228	pkg = SvSTASH(sv);
	229	}
	230	else {
	231	pkg = gv_stashsv(ST(0), FALSE);
	232	}
	233
	234	gvp = pkg ? (GV)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV);
	235
d4bea2fb	236	if (gvp && isGV(gv = *gvp) && SvOK(sv = GvSV(gv))) {
6d4a7be2	237	SV *nsv = sv_newmortal();
	238	sv_setsv(nsv, sv);
	239	sv = nsv;
	240	undef = Nullch;
	241	}
	242	else {
3280af22	243	sv = (SV*)&PL_sv_undef;
6d4a7be2	244	undef = "(undef)";
	245	}
	246
1571675a	247	if (items > 1) {
	248	STRLEN len;
	249	SV *req = ST(1);
	250
	251	if (undef)
	252	Perl_croak(aTHX_ "%s does not define $%s::VERSION--version check failed",
	253	HvNAME(pkg), HvNAME(pkg));
	254
	255	if (!SvNIOK(sv) && SvPOK(sv)) {
	256	char *str = SvPVx(sv,len);
	257	while (len) {
	258	--len;
	259	/* XXX could DWIM "1.2.3" here */
	260	if (!isDIGIT(str[len]) && str[len] != '.' && str[len] != '_')
	261	break;
	262	}
	263	if (len) {
4305d8ab	264	if (SvNOK(req) && SvPOK(req)) {
1571675a	265	/* they said C<use Foo v1.2.3> and $Foo::VERSION
	266	* doesn't look like a float: do string compare */
	267	if (sv_cmp(req,sv) == 1) {
d2560b70	268	Perl_croak(aTHX_ "%s v%"VDf" required--"
d2560b70	269	"this is only v%"VDf,
1571675a	270	HvNAME(pkg), req, sv);
	271	}
	272	goto finish;
	273	}
	274	/* they said C<use Foo 1.002_003> and $Foo::VERSION
	275	* doesn't look like a float: force numeric compare */
155aba94	276	(void)SvUPGRADE(sv, SVt_PVNV);
1571675a	277	SvNVX(sv) = str_to_version(sv);
	278	SvPOK_off(sv);
	279	SvNOK_on(sv);
	280	}
	281	}
	282	/* if we get here, we're looking for a numeric comparison,
	283	* so force the required version into a float, even if they
	284	* said C<use Foo v1.2.3> */
4305d8ab	285	if (SvNOK(req) && SvPOK(req)) {
1571675a	286	NV n = SvNV(req);
	287	req = sv_newmortal();
	288	sv_setnv(req, n);
	289	}
	290
	291	if (SvNV(req) > SvNV(sv))
	292	Perl_croak(aTHX_ "%s version %s required--this is only version %s",
	293	HvNAME(pkg), SvPV(req,len), SvPV(sv,len));
2d8e6c8d	294	}
6d4a7be2	295
1571675a	296	finish:
6d4a7be2	297	ST(0) = sv;
	298
	299	XSRETURN(1);
	300	}
	301