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tag: perl-5.8.7
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/* universal.c
*
* Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
* 2005, by Larry Wall and others
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
*
*/
/*
* "The roots of those mountains must be roots indeed; there must be
* great secrets buried there which have not been discovered since the
* beginning." --Gandalf, relating Gollum's story
*/
/* This file contains the code that implements the functions in Perl's
* UNIVERSAL package, such as UNIVERSAL->can().
*/
#include "EXTERN.h"
#define PERL_IN_UNIVERSAL_C
#include "perl.h"
#ifdef USE_PERLIO
#include "perliol.h" /* For the PERLIO_F_XXX */
#endif
/*
* 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 (strEQ(name, "UNIVERSAL"))
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) == (IV)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_ packWARN(WARN_SYNTAX),
"Can't locate package %"SVf" for @%s::ISA",
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 &PL_sv_no;
}
/*
=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_is_utf8);
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_Internals_SvREADONLY);
XS(XS_Internals_SvREFCNT);
XS(XS_Internals_hv_clear_placehold);
XS(XS_PerlIO_get_layers);
XS(XS_Regexp_DESTROY);
XS(XS_Internals_hash_seed);
XS(XS_Internals_rehash_seed);
XS(XS_Internals_HvREHASH);
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::is_utf8", XS_utf8_is_utf8, 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("Internals::SvREADONLY",XS_Internals_SvREADONLY, file, "\\[$%@];$");
newXSproto("Internals::SvREFCNT",XS_Internals_SvREFCNT, file, "\\[$%@];$");
newXSproto("Internals::hv_clear_placeholders",
XS_Internals_hv_clear_placehold, file, "\\%");
newXSproto("PerlIO::get_layers",
XS_PerlIO_get_layers, file, "*;@");
newXS("Regexp::DESTROY", XS_Regexp_DESTROY, file);
newXSproto("Internals::hash_seed",XS_Internals_hash_seed, file, "");
newXSproto("Internals::rehash_seed",XS_Internals_rehash_seed, file, "");
newXSproto("Internals::HvREHASH", XS_Internals_HvREHASH, 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))
|| (SvGMAGICAL(sv) && SvPOKp(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))
|| (SvGMAGICAL(sv) && SvPOKp(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) {
if (pkg)
Perl_croak(aTHX_
"%s does not define $%s::VERSION--version check failed",
HvNAME(pkg), HvNAME(pkg));
else {
char *str = SvPVx(ST(0), len);
Perl_croak(aTHX_
"%s defines neither package nor VERSION--version check failed", str);
}
}
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_is_utf8)
{
dXSARGS;
if (items != 1)
Perl_croak(aTHX_ "Usage: utf8::is_utf8(sv)");
{
SV * sv = ST(0);
{
if (SvUTF8(sv))
XSRETURN_YES;
else
XSRETURN_NO;
}
}
XSRETURN_EMPTY;
}
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_Internals_SvREADONLY) /* This is dangerous stuff. */
{
dXSARGS;
SV *sv = SvRV(ST(0));
if (items == 1) {
if (SvREADONLY(sv))
XSRETURN_YES;
else
XSRETURN_NO;
}
else if (items == 2) {
if (SvTRUE(ST(1))) {
SvREADONLY_on(sv);
XSRETURN_YES;
}
else {
/* I hope you really know what you are doing. */
SvREADONLY_off(sv);
XSRETURN_NO;
}
}
XSRETURN_UNDEF; /* Can't happen. */
}
XS(XS_Internals_SvREFCNT) /* This is dangerous stuff. */
{
dXSARGS;
SV *sv = SvRV(ST(0));
if (items == 1)
XSRETURN_IV(SvREFCNT(sv) - 1); /* Minus the ref created for us. */
else if (items == 2) {
/* I hope you really know what you are doing. */
SvREFCNT(sv) = SvIV(ST(1));
XSRETURN_IV(SvREFCNT(sv));
}
XSRETURN_UNDEF; /* Can't happen. */
}
XS(XS_Internals_hv_clear_placehold)
{
dXSARGS;
HV *hv = (HV *) SvRV(ST(0));
if (items != 1)
Perl_croak(aTHX_ "Usage: UNIVERSAL::hv_clear_placeholders(hv)");
hv_clear_placeholders(hv);
XSRETURN(0);
}
XS(XS_Regexp_DESTROY)
{
}
XS(XS_PerlIO_get_layers)
{
dXSARGS;
if (items < 1 || items % 2 == 0)
Perl_croak(aTHX_ "Usage: PerlIO_get_layers(filehandle[,args])");
#ifdef USE_PERLIO
{
SV * sv;
GV * gv;
IO * io;
bool input = TRUE;
bool details = FALSE;
if (items > 1) {
SV **svp;
for (svp = MARK + 2; svp <= SP; svp += 2) {
SV **varp = svp;
SV **valp = svp + 1;
STRLEN klen;
char *key = SvPV(*varp, klen);
switch (*key) {
case 'i':
if (klen == 5 && memEQ(key, "input", 5)) {
input = SvTRUE(*valp);
break;
}
goto fail;
case 'o':
if (klen == 6 && memEQ(key, "output", 6)) {
input = !SvTRUE(*valp);
break;
}
goto fail;
case 'd':
if (klen == 7 && memEQ(key, "details", 7)) {
details = SvTRUE(*valp);
break;
}
goto fail;
default:
fail:
Perl_croak(aTHX_
"get_layers: unknown argument '%s'",
key);
}
}
SP -= (items - 1);
}
sv = POPs;
gv = (GV*)sv;
if (!isGV(sv)) {
if (SvROK(sv) && isGV(SvRV(sv)))
gv = (GV*)SvRV(sv);
else
gv = gv_fetchpv(SvPVX(sv), FALSE, SVt_PVIO);
}
if (gv && (io = GvIO(gv))) {
dTARGET;
AV* av = PerlIO_get_layers(aTHX_ input ?
IoIFP(io) : IoOFP(io));
I32 i;
I32 last = av_len(av);
I32 nitem = 0;
for (i = last; i >= 0; i -= 3) {
SV **namsvp;
SV **argsvp;
SV **flgsvp;
bool namok, argok, flgok;
namsvp = av_fetch(av, i - 2, FALSE);
argsvp = av_fetch(av, i - 1, FALSE);
flgsvp = av_fetch(av, i, FALSE);
namok = namsvp && *namsvp && SvPOK(*namsvp);
argok = argsvp && *argsvp && SvPOK(*argsvp);
flgok = flgsvp && *flgsvp && SvIOK(*flgsvp);
if (details) {
XPUSHs(namok ?
newSVpv(SvPVX(*namsvp), 0) : &PL_sv_undef);
XPUSHs(argok ?
newSVpv(SvPVX(*argsvp), 0) : &PL_sv_undef);
if (flgok)
XPUSHi(SvIVX(*flgsvp));
else
XPUSHs(&PL_sv_undef);
nitem += 3;
}
else {
if (namok && argok)
XPUSHs(Perl_newSVpvf(aTHX_ "%"SVf"(%"SVf")",
*namsvp, *argsvp));
else if (namok)
XPUSHs(Perl_newSVpvf(aTHX_ "%"SVf, *namsvp));
else
XPUSHs(&PL_sv_undef);
nitem++;
if (flgok) {
IV flags = SvIVX(*flgsvp);
if (flags & PERLIO_F_UTF8) {
XPUSHs(newSVpvn("utf8", 4));
nitem++;
}
}
}
}
SvREFCNT_dec(av);
XSRETURN(nitem);
}
}
#endif
XSRETURN(0);
}
XS(XS_Internals_hash_seed)
{
/* Using dXSARGS would also have dITEM and dSP,
* which define 2 unused local variables. */
dMARK; dAX;
XSRETURN_UV(PERL_HASH_SEED);
}
XS(XS_Internals_rehash_seed)
{
/* Using dXSARGS would also have dITEM and dSP,
* which define 2 unused local variables. */
dMARK; dAX;
XSRETURN_UV(PL_rehash_seed);
}
XS(XS_Internals_HvREHASH) /* Subject to change */
{
dXSARGS;
if (SvROK(ST(0))) {
HV *hv = (HV *) SvRV(ST(0));
if (items == 1 && SvTYPE(hv) == SVt_PVHV) {
if (HvREHASH(hv))
XSRETURN_YES;
else
XSRETURN_NO;
}
}
Perl_croak(aTHX_ "Internals::HvREHASH $hashref");
}
/*
* Local variables:
* c-indentation-style: bsd
* c-basic-offset: 4
* indent-tabs-mode: t
* End:
*
* vim: shiftwidth=4:
*/
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