[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, HV* name_stash,
             int len, int level)
{
    AV* av;
    GV* gv;
    GV** gvp;
    HV* hv = Nullhv;
    SV* subgen = Nullsv;

    /* A stash/class can go by many names (ie. User == main::User), so 
       we compare the stash itself just in case */
    if (name_stash && (stash == name_stash))
        return &PL_sv_yes;

    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, name_stash, 
                                             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"));
}

/*
=head1 SV Manipulation Functions

=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;
    HV *name_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);
    }

    name_stash = gv_stashpv(name, FALSE);

    return (type && strEQ(type,name)) ||
            (stash && isa_lookup(stash, name, name_stash, 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 *
301daebc MS	11	S_isa_lookup(pTHX_ HV stash, const char name, HV* name_stash,
301daebc MS	12	int len, int level)
6d4a7be2	13	{
	14	AV* av;
	15	GV* gv;
	16	GV** gvp;
	17	HV* hv = Nullhv;
46e4b22b	18	SV* subgen = Nullsv;
6d4a7be2	19
301daebc MS	20	/* A stash/class can go by many names (ie. User == main::User), so
	21	we compare the stash itself just in case */
	22	if (name_stash && (stash == name_stash))
	23	return &PL_sv_yes;
6d4a7be2	24
46e4b22b	25	if (strEQ(HvNAME(stash), name))
3280af22	26	return &PL_sv_yes;
6d4a7be2	27
6d4a7be2	28	if (level > 100)
46e4b22b GS	29	Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
46e4b22b GS	30	HvNAME(stash));
6d4a7be2	31
	32	gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);
	33
46e4b22b GS	34	if (gvp && (gv = gvp) != (GV)&PL_sv_undef && (subgen = GvSV(gv))
	35	&& (hv = GvHV(gv)))
	36	{
	37	if (SvIV(subgen) == PL_sub_generation) {
	38	SV* sv;
	39	SV svp = (SV)hv_fetch(hv, name, len, FALSE);
	40	if (svp && (sv = svp) != (SV)&PL_sv_undef) {
	41	DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
	42	name, HvNAME(stash)) );
	43	return sv;
	44	}
	45	}
	46	else {
	47	DEBUG_o( Perl_deb(aTHX_ "ISA Cache in package %s is stale\n",
	48	HvNAME(stash)) );
	49	hv_clear(hv);
	50	sv_setiv(subgen, PL_sub_generation);
	51	}
6d4a7be2	52	}
	53
	54	gvp = (GV**)hv_fetch(stash,"ISA",3,FALSE);
46e4b22b	55
3280af22	56	if (gvp && (gv = gvp) != (GV)&PL_sv_undef && (av = GvAV(gv))) {
46e4b22b	57	if (!hv \|\| !subgen) {
6d4a7be2	58	gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, TRUE);
	59
	60	gv = *gvp;
	61
	62	if (SvTYPE(gv) != SVt_PVGV)
	63	gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
	64
46e4b22b GS	65	if (!hv)
	66	hv = GvHVn(gv);
	67	if (!subgen) {
	68	subgen = newSViv(PL_sub_generation);
	69	GvSV(gv) = subgen;
	70	}
6d4a7be2	71	}
46e4b22b	72	if (hv) {
6d4a7be2	73	SV** svp = AvARRAY(av);
93965878 NIS	74	/* NOTE: No support for tied ISA */
93965878 NIS	75	I32 items = AvFILLp(av) + 1;
6d4a7be2	76	while (items--) {
	77	SV* sv = *svp++;
	78	HV* basestash = gv_stashsv(sv, FALSE);
	79	if (!basestash) {
599cee73	80	if (ckWARN(WARN_MISC))
cea2e8a9	81	Perl_warner(aTHX_ WARN_SYNTAX,
599cee73	82	"Can't locate package %s for @%s::ISA",
6d4a7be2	83	SvPVX(sv), HvNAME(stash));
	84	continue;
	85	}
301daebc MS	86	if (&PL_sv_yes == isa_lookup(basestash, name, name_stash,
301daebc MS	87	len, level + 1)) {
3280af22 NIS	88	(void)hv_store(hv,name,len,&PL_sv_yes,0);
3280af22 NIS	89	return &PL_sv_yes;
6d4a7be2	90	}
6d4a7be2	91	}
3280af22	92	(void)hv_store(hv,name,len,&PL_sv_no,0);
6d4a7be2	93	}
	94	}
	95
e09f3e01	96	return boolSV(strEQ(name, "UNIVERSAL"));
6d4a7be2	97	}
6d4a7be2	98
954c1994	99	/*
ccfc67b7 JH	100	=head1 SV Manipulation Functions
ccfc67b7 JH	101
954c1994 GS	102	=for apidoc sv_derived_from
	103
	104	Returns a boolean indicating whether the SV is derived from the specified
	105	class. This is the function that implements C<UNIVERSAL::isa>. It works
	106	for class names as well as for objects.
	107
	108	=cut
	109	*/
	110
55497cff	111	bool
864dbfa3	112	Perl_sv_derived_from(pTHX_ SV sv, const char name)
55497cff	113	{
55497cff	114	char *type;
55497cff	115	HV *stash;
301daebc	116	HV *name_stash;
46e4b22b	117
55497cff	118	stash = Nullhv;
55497cff	119	type = Nullch;
46e4b22b	120
55497cff	121	if (SvGMAGICAL(sv))
	122	mg_get(sv) ;
	123
	124	if (SvROK(sv)) {
	125	sv = SvRV(sv);
	126	type = sv_reftype(sv,0);
46e4b22b	127	if (SvOBJECT(sv))
55497cff	128	stash = SvSTASH(sv);
	129	}
	130	else {
	131	stash = gv_stashsv(sv, FALSE);
	132	}
46e4b22b	133
301daebc MS	134	name_stash = gv_stashpv(name, FALSE);
301daebc MS	135
55497cff	136	return (type && strEQ(type,name)) \|\|
301daebc MS	137	(stash && isa_lookup(stash, name, name_stash, strlen(name), 0)
301daebc MS	138	== &PL_sv_yes)
55497cff	139	? TRUE
55497cff	140	: FALSE ;
55497cff	141	}
55497cff	142
1b026014 NIS	143	#include "XSUB.h"
1b026014 NIS	144
acfe0abc GS	145	void XS_UNIVERSAL_isa(pTHX_ CV *cv);
	146	void XS_UNIVERSAL_can(pTHX_ CV *cv);
	147	void XS_UNIVERSAL_VERSION(pTHX_ CV *cv);
1b026014 NIS	148	XS(XS_utf8_valid);
	149	XS(XS_utf8_encode);
	150	XS(XS_utf8_decode);
	151	XS(XS_utf8_upgrade);
	152	XS(XS_utf8_downgrade);
	153	XS(XS_utf8_unicode_to_native);
	154	XS(XS_utf8_native_to_unicode);
1b1f1335	155	XS(XS_access_readonly);
0cb96387 GS	156
	157	void
	158	Perl_boot_core_UNIVERSAL(pTHX)
	159	{
	160	char *file = __FILE__;
	161
	162	newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
	163	newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
	164	newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
1b026014 NIS	165	newXS("utf8::valid", XS_utf8_valid, file);
	166	newXS("utf8::encode", XS_utf8_encode, file);
	167	newXS("utf8::decode", XS_utf8_decode, file);
	168	newXS("utf8::upgrade", XS_utf8_upgrade, file);
	169	newXS("utf8::downgrade", XS_utf8_downgrade, file);
	170	newXS("utf8::native_to_unicode", XS_utf8_native_to_unicode, file);
	171	newXS("utf8::unicode_to_native", XS_utf8_unicode_to_native, file);
1b1f1335	172	newXSproto("access::readonly",XS_access_readonly, file, "\\[$%@];$");
0cb96387 GS	173	}
0cb96387 GS	174
55497cff	175
6d4a7be2	176	XS(XS_UNIVERSAL_isa)
	177	{
	178	dXSARGS;
55497cff	179	SV *sv;
55497cff	180	char *name;
2d8e6c8d	181	STRLEN n_a;
6d4a7be2	182
6d4a7be2	183	if (items != 2)
cea2e8a9	184	Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
6d4a7be2	185
6d4a7be2	186	sv = ST(0);
f8f70380	187
d3f7f2b2 GS	188	if (SvGMAGICAL(sv))
	189	mg_get(sv);
	190
aca069ec	191	if (!SvOK(sv) \|\| !(SvROK(sv) \|\| (SvPOK(sv) && SvCUR(sv))))
f8f70380 GS	192	XSRETURN_UNDEF;
f8f70380 GS	193
2d8e6c8d	194	name = (char *)SvPV(ST(1),n_a);
6d4a7be2	195
54310121	196	ST(0) = boolSV(sv_derived_from(sv, name));
6d4a7be2	197	XSRETURN(1);
	198	}
	199
6d4a7be2	200	XS(XS_UNIVERSAL_can)
	201	{
	202	dXSARGS;
	203	SV *sv;
	204	char *name;
	205	SV *rv;
6f08146e	206	HV *pkg = NULL;
2d8e6c8d	207	STRLEN n_a;
6d4a7be2	208
6d4a7be2	209	if (items != 2)
cea2e8a9	210	Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
6d4a7be2	211
6d4a7be2	212	sv = ST(0);
f8f70380	213
d3f7f2b2 GS	214	if (SvGMAGICAL(sv))
	215	mg_get(sv);
	216
aca069ec	217	if (!SvOK(sv) \|\| !(SvROK(sv) \|\| (SvPOK(sv) && SvCUR(sv))))
f8f70380 GS	218	XSRETURN_UNDEF;
f8f70380 GS	219
2d8e6c8d	220	name = (char *)SvPV(ST(1),n_a);
3280af22	221	rv = &PL_sv_undef;
6d4a7be2	222
46e4b22b	223	if (SvROK(sv)) {
6f08146e	224	sv = (SV*)SvRV(sv);
46e4b22b	225	if (SvOBJECT(sv))
6f08146e NIS	226	pkg = SvSTASH(sv);
	227	}
	228	else {
	229	pkg = gv_stashsv(sv, FALSE);
	230	}
	231
	232	if (pkg) {
dc848c6f	233	GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
	234	if (gv && isGV(gv))
	235	rv = sv_2mortal(newRV((SV*)GvCV(gv)));
6d4a7be2	236	}
	237
	238	ST(0) = rv;
	239	XSRETURN(1);
	240	}
	241
6d4a7be2	242	XS(XS_UNIVERSAL_VERSION)
	243	{
	244	dXSARGS;
	245	HV *pkg;
	246	GV **gvp;
	247	GV *gv;
	248	SV *sv;
	249	char *undef;
	250
1571675a	251	if (SvROK(ST(0))) {
6d4a7be2	252	sv = (SV*)SvRV(ST(0));
1571675a	253	if (!SvOBJECT(sv))
cea2e8a9	254	Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
6d4a7be2	255	pkg = SvSTASH(sv);
	256	}
	257	else {
	258	pkg = gv_stashsv(ST(0), FALSE);
	259	}
	260
	261	gvp = pkg ? (GV)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV);
	262
d4bea2fb	263	if (gvp && isGV(gv = *gvp) && SvOK(sv = GvSV(gv))) {
6d4a7be2	264	SV *nsv = sv_newmortal();
	265	sv_setsv(nsv, sv);
	266	sv = nsv;
	267	undef = Nullch;
	268	}
	269	else {
3280af22	270	sv = (SV*)&PL_sv_undef;
6d4a7be2	271	undef = "(undef)";
	272	}
	273
1571675a GS	274	if (items > 1) {
	275	STRLEN len;
	276	SV *req = ST(1);
	277
	278	if (undef)
	279	Perl_croak(aTHX_ "%s does not define $%s::VERSION--version check failed",
	280	HvNAME(pkg), HvNAME(pkg));
	281
	282	if (!SvNIOK(sv) && SvPOK(sv)) {
	283	char *str = SvPVx(sv,len);
	284	while (len) {
	285	--len;
	286	/* XXX could DWIM "1.2.3" here */
	287	if (!isDIGIT(str[len]) && str[len] != '.' && str[len] != '_')
	288	break;
	289	}
	290	if (len) {
4305d8ab	291	if (SvNOK(req) && SvPOK(req)) {
1571675a GS	292	/* they said C<use Foo v1.2.3> and $Foo::VERSION
	293	* doesn't look like a float: do string compare */
	294	if (sv_cmp(req,sv) == 1) {
d2560b70 RB	295	Perl_croak(aTHX_ "%s v%"VDf" required--"
d2560b70 RB	296	"this is only v%"VDf,
1571675a GS	297	HvNAME(pkg), req, sv);
	298	}
	299	goto finish;
	300	}
	301	/* they said C<use Foo 1.002_003> and $Foo::VERSION
	302	* doesn't look like a float: force numeric compare */
155aba94	303	(void)SvUPGRADE(sv, SVt_PVNV);
1571675a GS	304	SvNVX(sv) = str_to_version(sv);
	305	SvPOK_off(sv);
	306	SvNOK_on(sv);
	307	}
	308	}
	309	/* if we get here, we're looking for a numeric comparison,
	310	* so force the required version into a float, even if they
	311	* said C<use Foo v1.2.3> */
4305d8ab	312	if (SvNOK(req) && SvPOK(req)) {
1571675a GS	313	NV n = SvNV(req);
	314	req = sv_newmortal();
	315	sv_setnv(req, n);
	316	}
	317
f6eb1a96	318	if (SvNV(req) > SvNV(sv))
1571675a	319	Perl_croak(aTHX_ "%s version %s required--this is only version %s",
f6eb1a96	320	HvNAME(pkg), SvPV_nolen(req), SvPV_nolen(sv));
2d8e6c8d	321	}
6d4a7be2	322
1571675a	323	finish:
6d4a7be2	324	ST(0) = sv;
	325
	326	XSRETURN(1);
	327	}
	328
1b026014 NIS	329	XS(XS_utf8_valid)
	330	{
	331	dXSARGS;
	332	if (items != 1)
	333	Perl_croak(aTHX_ "Usage: utf8::valid(sv)");
	334	{
	335	SV * sv = ST(0);
	336	{
	337	STRLEN len;
	338	char *s = SvPV(sv,len);
	339	if (!SvUTF8(sv) \|\| is_utf8_string((U8*)s,len))
	340	XSRETURN_YES;
	341	else
	342	XSRETURN_NO;
	343	}
	344	}
	345	XSRETURN_EMPTY;
	346	}
	347
	348	XS(XS_utf8_encode)
	349	{
	350	dXSARGS;
	351	if (items != 1)
	352	Perl_croak(aTHX_ "Usage: utf8::encode(sv)");
	353	{
	354	SV * sv = ST(0);
	355
	356	sv_utf8_encode(sv);
	357	}
	358	XSRETURN_EMPTY;
	359	}
	360
	361	XS(XS_utf8_decode)
	362	{
	363	dXSARGS;
	364	if (items != 1)
	365	Perl_croak(aTHX_ "Usage: utf8::decode(sv)");
	366	{
	367	SV * sv = ST(0);
	368	bool RETVAL;
	369
	370	RETVAL = sv_utf8_decode(sv);
	371	ST(0) = boolSV(RETVAL);
	372	sv_2mortal(ST(0));
	373	}
	374	XSRETURN(1);
	375	}
	376
	377	XS(XS_utf8_upgrade)
	378	{
	379	dXSARGS;
	380	if (items != 1)
	381	Perl_croak(aTHX_ "Usage: utf8::upgrade(sv)");
	382	{
	383	SV * sv = ST(0);
	384	STRLEN RETVAL;
	385	dXSTARG;
	386
	387	RETVAL = sv_utf8_upgrade(sv);
	388	XSprePUSH; PUSHi((IV)RETVAL);
	389	}
	390	XSRETURN(1);
	391	}
	392
393	XS(XS_utf8_downgrade)
394	{
395	dXSARGS;
396	if (items < 1 \|\| items > 2)
397	Perl_croak(aTHX_ "Usage: utf8::downgrade(sv, failok=0)");
398	{
399	SV * sv = ST(0);
400	bool failok;
401	bool RETVAL;
402
403	if (items < 2)
404	failok = 0;
405	else {
406	failok = (int)SvIV(ST(1));
407	}
408
409	RETVAL = sv_utf8_downgrade(sv, failok);
410	ST(0) = boolSV(RETVAL);
411	sv_2mortal(ST(0));
412	}
413	XSRETURN(1);
414	}
415
416	XS(XS_utf8_native_to_unicode)
417	{
418	dXSARGS;
419	UV uv = SvUV(ST(0));
b7953727 JH	420
	421	if (items > 1)
	422	Perl_croak(aTHX_ "Usage: utf8::native_to_unicode(sv)");
	423
1b026014 NIS	424	ST(0) = sv_2mortal(newSViv(NATIVE_TO_UNI(uv)));
	425	XSRETURN(1);
	426	}
	427
	428	XS(XS_utf8_unicode_to_native)
	429	{
	430	dXSARGS;
	431	UV uv = SvUV(ST(0));
b7953727 JH	432
	433	if (items > 1)
	434	Perl_croak(aTHX_ "Usage: utf8::unicode_to_native(sv)");
	435
1b026014 NIS	436	ST(0) = sv_2mortal(newSViv(UNI_TO_NATIVE(uv)));
	437	XSRETURN(1);
	438	}
	439
1b1f1335 NIS	440	XS(XS_access_readonly)
	441	{
	442	dXSARGS;
	443	SV *sv = SvRV(ST(0));
	444	IV old = SvREADONLY(sv);
	445	if (items == 2) {
	446	if (SvTRUE(ST(1))) {
	447	SvREADONLY_on(sv);
	448	}
	449	else {
	450	SvREADONLY_off(sv);
	451	}
	452	}
	453	if (old)
	454	XSRETURN_YES;
	455	else
	456	XSRETURN_NO;
	457	}
1b026014	458