[perl5.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 ;
}

#include "XSUB.h"

void XS_UNIVERSAL_isa(pTHX_ CV *cv);
void XS_UNIVERSAL_can(pTHX_ CV *cv);
void XS_UNIVERSAL_VERSION(pTHX_ CV *cv);
XS(XS_utf8_valid);
XS(XS_utf8_encode);
XS(XS_utf8_decode);
XS(XS_utf8_upgrade);
XS(XS_utf8_downgrade);
XS(XS_utf8_unicode_to_native);
XS(XS_utf8_native_to_unicode);
XS(XS_access_readonly);

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);
    newXS("utf8::valid", XS_utf8_valid, file);
    newXS("utf8::encode", XS_utf8_encode, file);
    newXS("utf8::decode", XS_utf8_decode, file);
    newXS("utf8::upgrade", XS_utf8_upgrade, file);
    newXS("utf8::downgrade", XS_utf8_downgrade, file);
    newXS("utf8::native_to_unicode", XS_utf8_native_to_unicode, file);
    newXS("utf8::unicode_to_native", XS_utf8_unicode_to_native, file);
    newXSproto("access::readonly",XS_access_readonly, file, "\\[$%@];$");
}


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_nolen(req), SvPV_nolen(sv));
    }

finish:
    ST(0) = sv;

    XSRETURN(1);
}

XS(XS_utf8_valid)
{
    dXSARGS;
    if (items != 1)
	Perl_croak(aTHX_ "Usage: utf8::valid(sv)");
    {
	SV *	sv = ST(0);
 {
  STRLEN len;
  char *s = SvPV(sv,len);
  if (!SvUTF8(sv) || is_utf8_string((U8*)s,len))
   XSRETURN_YES;
  else
   XSRETURN_NO;
 }
    }
    XSRETURN_EMPTY;
}

XS(XS_utf8_encode)
{
    dXSARGS;
    if (items != 1)
	Perl_croak(aTHX_ "Usage: utf8::encode(sv)");
    {
	SV *	sv = ST(0);

	sv_utf8_encode(sv);
    }
    XSRETURN_EMPTY;
}

XS(XS_utf8_decode)
{
    dXSARGS;
    if (items != 1)
	Perl_croak(aTHX_ "Usage: utf8::decode(sv)");
    {
	SV *	sv = ST(0);
	bool	RETVAL;

	RETVAL = sv_utf8_decode(sv);
	ST(0) = boolSV(RETVAL);
	sv_2mortal(ST(0));
    }
    XSRETURN(1);
}

XS(XS_utf8_upgrade)
{
    dXSARGS;
    if (items != 1)
	Perl_croak(aTHX_ "Usage: utf8::upgrade(sv)");
    {
	SV *	sv = ST(0);
	STRLEN	RETVAL;
	dXSTARG;

	RETVAL = sv_utf8_upgrade(sv);
	XSprePUSH; PUSHi((IV)RETVAL);
    }
    XSRETURN(1);
}

XS(XS_utf8_downgrade)
{
    dXSARGS;
    if (items < 1 || items > 2)
	Perl_croak(aTHX_ "Usage: utf8::downgrade(sv, failok=0)");
    {
	SV *	sv = ST(0);
	bool	failok;
	bool	RETVAL;

	if (items < 2)
	    failok = 0;
	else {
	    failok = (int)SvIV(ST(1));
	}

	RETVAL = sv_utf8_downgrade(sv, failok);
	ST(0) = boolSV(RETVAL);
	sv_2mortal(ST(0));
    }
    XSRETURN(1);
}

XS(XS_utf8_native_to_unicode)
{
 dXSARGS;
 UV uv = SvUV(ST(0));

 if (items > 1)
     Perl_croak(aTHX_ "Usage: utf8::native_to_unicode(sv)");

 ST(0) = sv_2mortal(newSViv(NATIVE_TO_UNI(uv)));
 XSRETURN(1);
}

XS(XS_utf8_unicode_to_native)
{
 dXSARGS;
 UV uv = SvUV(ST(0));

 if (items > 1)
     Perl_croak(aTHX_ "Usage: utf8::unicode_to_native(sv)");

 ST(0) = sv_2mortal(newSViv(UNI_TO_NATIVE(uv)));
 XSRETURN(1);
}

XS(XS_access_readonly)
{
    dXSARGS;
    SV *sv = SvRV(ST(0));
    IV old = SvREADONLY(sv);
    if (items == 2) {
	if (SvTRUE(ST(1))) {
	    SvREADONLY_on(sv);
	}
	else {
	    SvREADONLY_off(sv);
	}
    }
    if (old)
	XSRETURN_YES;
    else
	XSRETURN_NO;
}
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 GS	26	Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
46e4b22b GS	27	HvNAME(stash));
6d4a7be2	28
	29	gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);
	30
46e4b22b GS	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 GS	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 NIS	71	/* NOTE: No support for tied ISA */
93965878 NIS	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 NIS	84	(void)hv_store(hv,name,len,&PL_sv_yes,0);
3280af22 NIS	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 GS	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
1b026014 NIS	133	#include "XSUB.h"
1b026014 NIS	134
acfe0abc GS	135	void XS_UNIVERSAL_isa(pTHX_ CV *cv);
	136	void XS_UNIVERSAL_can(pTHX_ CV *cv);
	137	void XS_UNIVERSAL_VERSION(pTHX_ CV *cv);
1b026014 NIS	138	XS(XS_utf8_valid);
	139	XS(XS_utf8_encode);
	140	XS(XS_utf8_decode);
	141	XS(XS_utf8_upgrade);
	142	XS(XS_utf8_downgrade);
	143	XS(XS_utf8_unicode_to_native);
	144	XS(XS_utf8_native_to_unicode);
1b1f1335	145	XS(XS_access_readonly);
0cb96387 GS	146
	147	void
	148	Perl_boot_core_UNIVERSAL(pTHX)
	149	{
	150	char *file = __FILE__;
	151
	152	newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
	153	newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
	154	newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
1b026014 NIS	155	newXS("utf8::valid", XS_utf8_valid, file);
	156	newXS("utf8::encode", XS_utf8_encode, file);
	157	newXS("utf8::decode", XS_utf8_decode, file);
	158	newXS("utf8::upgrade", XS_utf8_upgrade, file);
	159	newXS("utf8::downgrade", XS_utf8_downgrade, file);
	160	newXS("utf8::native_to_unicode", XS_utf8_native_to_unicode, file);
	161	newXS("utf8::unicode_to_native", XS_utf8_unicode_to_native, file);
1b1f1335	162	newXSproto("access::readonly",XS_access_readonly, file, "\\[$%@];$");
0cb96387 GS	163	}
0cb96387 GS	164
55497cff	165
6d4a7be2	166	XS(XS_UNIVERSAL_isa)
	167	{
	168	dXSARGS;
55497cff	169	SV *sv;
55497cff	170	char *name;
2d8e6c8d	171	STRLEN n_a;
6d4a7be2	172
6d4a7be2	173	if (items != 2)
cea2e8a9	174	Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
6d4a7be2	175
6d4a7be2	176	sv = ST(0);
f8f70380	177
d3f7f2b2 GS	178	if (SvGMAGICAL(sv))
	179	mg_get(sv);
	180
aca069ec	181	if (!SvOK(sv) \|\| !(SvROK(sv) \|\| (SvPOK(sv) && SvCUR(sv))))
f8f70380 GS	182	XSRETURN_UNDEF;
f8f70380 GS	183
2d8e6c8d	184	name = (char *)SvPV(ST(1),n_a);
6d4a7be2	185
54310121	186	ST(0) = boolSV(sv_derived_from(sv, name));
6d4a7be2	187	XSRETURN(1);
	188	}
	189
6d4a7be2	190	XS(XS_UNIVERSAL_can)
	191	{
	192	dXSARGS;
	193	SV *sv;
	194	char *name;
	195	SV *rv;
6f08146e	196	HV *pkg = NULL;
2d8e6c8d	197	STRLEN n_a;
6d4a7be2	198
6d4a7be2	199	if (items != 2)
cea2e8a9	200	Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
6d4a7be2	201
6d4a7be2	202	sv = ST(0);
f8f70380	203
d3f7f2b2 GS	204	if (SvGMAGICAL(sv))
	205	mg_get(sv);
	206
aca069ec	207	if (!SvOK(sv) \|\| !(SvROK(sv) \|\| (SvPOK(sv) && SvCUR(sv))))
f8f70380 GS	208	XSRETURN_UNDEF;
f8f70380 GS	209
2d8e6c8d	210	name = (char *)SvPV(ST(1),n_a);
3280af22	211	rv = &PL_sv_undef;
6d4a7be2	212
46e4b22b	213	if (SvROK(sv)) {
6f08146e	214	sv = (SV*)SvRV(sv);
46e4b22b	215	if (SvOBJECT(sv))
6f08146e NIS	216	pkg = SvSTASH(sv);
	217	}
	218	else {
	219	pkg = gv_stashsv(sv, FALSE);
	220	}
	221
	222	if (pkg) {
dc848c6f	223	GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
	224	if (gv && isGV(gv))
	225	rv = sv_2mortal(newRV((SV*)GvCV(gv)));
6d4a7be2	226	}
	227
	228	ST(0) = rv;
	229	XSRETURN(1);
	230	}
	231
6d4a7be2	232	XS(XS_UNIVERSAL_VERSION)
	233	{
	234	dXSARGS;
	235	HV *pkg;
	236	GV **gvp;
	237	GV *gv;
	238	SV *sv;
	239	char *undef;
	240
1571675a	241	if (SvROK(ST(0))) {
6d4a7be2	242	sv = (SV*)SvRV(ST(0));
1571675a	243	if (!SvOBJECT(sv))
cea2e8a9	244	Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
6d4a7be2	245	pkg = SvSTASH(sv);
	246	}
	247	else {
	248	pkg = gv_stashsv(ST(0), FALSE);
	249	}
	250
	251	gvp = pkg ? (GV)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV);
	252
d4bea2fb	253	if (gvp && isGV(gv = *gvp) && SvOK(sv = GvSV(gv))) {
6d4a7be2	254	SV *nsv = sv_newmortal();
	255	sv_setsv(nsv, sv);
	256	sv = nsv;
	257	undef = Nullch;
	258	}
	259	else {
3280af22	260	sv = (SV*)&PL_sv_undef;
6d4a7be2	261	undef = "(undef)";
	262	}
	263
1571675a GS	264	if (items > 1) {
	265	STRLEN len;
	266	SV *req = ST(1);
	267
	268	if (undef)
	269	Perl_croak(aTHX_ "%s does not define $%s::VERSION--version check failed",
	270	HvNAME(pkg), HvNAME(pkg));
	271
	272	if (!SvNIOK(sv) && SvPOK(sv)) {
	273	char *str = SvPVx(sv,len);
	274	while (len) {
	275	--len;
	276	/* XXX could DWIM "1.2.3" here */
	277	if (!isDIGIT(str[len]) && str[len] != '.' && str[len] != '_')
	278	break;
	279	}
	280	if (len) {
4305d8ab	281	if (SvNOK(req) && SvPOK(req)) {
1571675a GS	282	/* they said C<use Foo v1.2.3> and $Foo::VERSION
	283	* doesn't look like a float: do string compare */
	284	if (sv_cmp(req,sv) == 1) {
d2560b70 RB	285	Perl_croak(aTHX_ "%s v%"VDf" required--"
d2560b70 RB	286	"this is only v%"VDf,
1571675a GS	287	HvNAME(pkg), req, sv);
	288	}
	289	goto finish;
	290	}
	291	/* they said C<use Foo 1.002_003> and $Foo::VERSION
	292	* doesn't look like a float: force numeric compare */
155aba94	293	(void)SvUPGRADE(sv, SVt_PVNV);
1571675a GS	294	SvNVX(sv) = str_to_version(sv);
	295	SvPOK_off(sv);
	296	SvNOK_on(sv);
	297	}
	298	}
	299	/* if we get here, we're looking for a numeric comparison,
	300	* so force the required version into a float, even if they
	301	* said C<use Foo v1.2.3> */
4305d8ab	302	if (SvNOK(req) && SvPOK(req)) {
1571675a GS	303	NV n = SvNV(req);
	304	req = sv_newmortal();
	305	sv_setnv(req, n);
	306	}
	307
f6eb1a96	308	if (SvNV(req) > SvNV(sv))
1571675a	309	Perl_croak(aTHX_ "%s version %s required--this is only version %s",
f6eb1a96	310	HvNAME(pkg), SvPV_nolen(req), SvPV_nolen(sv));
2d8e6c8d	311	}
6d4a7be2	312
1571675a	313	finish:
6d4a7be2	314	ST(0) = sv;
	315
	316	XSRETURN(1);
	317	}
	318
1b026014 NIS	319	XS(XS_utf8_valid)
	320	{
	321	dXSARGS;
	322	if (items != 1)
	323	Perl_croak(aTHX_ "Usage: utf8::valid(sv)");
	324	{
	325	SV * sv = ST(0);
	326	{
	327	STRLEN len;
	328	char *s = SvPV(sv,len);
	329	if (!SvUTF8(sv) \|\| is_utf8_string((U8*)s,len))
	330	XSRETURN_YES;
	331	else
	332	XSRETURN_NO;
	333	}
	334	}
	335	XSRETURN_EMPTY;
	336	}
	337
	338	XS(XS_utf8_encode)
	339	{
	340	dXSARGS;
	341	if (items != 1)
	342	Perl_croak(aTHX_ "Usage: utf8::encode(sv)");
	343	{
	344	SV * sv = ST(0);
	345
	346	sv_utf8_encode(sv);
	347	}
	348	XSRETURN_EMPTY;
	349	}
	350
	351	XS(XS_utf8_decode)
	352	{
	353	dXSARGS;
	354	if (items != 1)
	355	Perl_croak(aTHX_ "Usage: utf8::decode(sv)");
	356	{
	357	SV * sv = ST(0);
	358	bool RETVAL;
	359
	360	RETVAL = sv_utf8_decode(sv);
	361	ST(0) = boolSV(RETVAL);
	362	sv_2mortal(ST(0));
	363	}
	364	XSRETURN(1);
	365	}
	366
	367	XS(XS_utf8_upgrade)
	368	{
	369	dXSARGS;
	370	if (items != 1)
	371	Perl_croak(aTHX_ "Usage: utf8::upgrade(sv)");
	372	{
	373	SV * sv = ST(0);
	374	STRLEN RETVAL;
	375	dXSTARG;
	376
	377	RETVAL = sv_utf8_upgrade(sv);
	378	XSprePUSH; PUSHi((IV)RETVAL);
	379	}
	380	XSRETURN(1);
	381	}
	382
383	XS(XS_utf8_downgrade)
384	{
385	dXSARGS;
386	if (items < 1 \|\| items > 2)
387	Perl_croak(aTHX_ "Usage: utf8::downgrade(sv, failok=0)");
388	{
389	SV * sv = ST(0);
390	bool failok;
391	bool RETVAL;
392
393	if (items < 2)
394	failok = 0;
395	else {
396	failok = (int)SvIV(ST(1));
397	}
398
399	RETVAL = sv_utf8_downgrade(sv, failok);
400	ST(0) = boolSV(RETVAL);
401	sv_2mortal(ST(0));
402	}
403	XSRETURN(1);
404	}
405
406	XS(XS_utf8_native_to_unicode)
407	{
408	dXSARGS;
409	UV uv = SvUV(ST(0));
b7953727 JH	410
	411	if (items > 1)
	412	Perl_croak(aTHX_ "Usage: utf8::native_to_unicode(sv)");
	413
1b026014 NIS	414	ST(0) = sv_2mortal(newSViv(NATIVE_TO_UNI(uv)));
	415	XSRETURN(1);
	416	}
	417
	418	XS(XS_utf8_unicode_to_native)
	419	{
	420	dXSARGS;
	421	UV uv = SvUV(ST(0));
b7953727 JH	422
	423	if (items > 1)
	424	Perl_croak(aTHX_ "Usage: utf8::unicode_to_native(sv)");
	425
1b026014 NIS	426	ST(0) = sv_2mortal(newSViv(UNI_TO_NATIVE(uv)));
	427	XSRETURN(1);
	428	}
	429
1b1f1335 NIS	430	XS(XS_access_readonly)
	431	{
	432	dXSARGS;
	433	SV *sv = SvRV(ST(0));
	434	IV old = SvREADONLY(sv);
	435	if (items == 2) {
	436	if (SvTRUE(ST(1))) {
	437	SvREADONLY_on(sv);
	438	}
	439	else {
	440	SvREADONLY_off(sv);
	441	}
	442	}
	443	if (old)
	444	XSRETURN_YES;
	445	else
	446	XSRETURN_NO;
	447	}
1b026014	448