#ifdef WIN32 /* Win32 doesn't get PERL_CORE, so use the next best thing */
#define PERL_NO_GET_CONTEXT
#endif
#include "EXTERN.h"
#include "perl.h"
/*
* chocolateboy 2009-02-08
*
* for binary compatibility (see perlapi.h), XS modules perform a function call to
* access each and every interpreter variable. So, for instance, an innocuous-looking
* reference to PL_op becomes:
*
* (*Perl_Iop_ptr(my_perl))
*
* This (obviously) impacts performance. Internally, PL_op is accessed as:
*
* my_perl->Iop
*
* (in threaded/multiplicity builds (see intrpvar.h)), which is significantly faster.
*
* defining PERL_CORE gets us the fast version, at the expense of a future maintenance release
* possibly breaking things: https://groups.google.com/group/perl.perl5.porters/browse_thread/thread/9ec0da3f02b3b5a
*
* Rather than globally defining PERL_CORE, which pokes its fingers into various headers, exposing
* internals we'd rather not see, just define it for XSUB.h, which includes
* perlapi.h, which imposes the speed limit.
*/
#ifdef WIN32 /* thanks to Andy Grundman for pointing out problems with this on ActivePerl >= 5.10 */
#include "XSUB.h"
#else /* not WIN32 */
#define PERL_CORE
#include "XSUB.h"
#undef PERL_CORE
#endif
#define NEED_sv_2pv_flags
#include "ppport.h"
#include "ptable.h"
static PTABLE_t *AUTOBOX_OP_MAP = NULL;
static U32 AUTOBOX_SCOPE_DEPTH = 0;
static OP *(*autobox_old_check_entersub)(pTHX_ OP *op) = NULL;
static SV * autobox_method_common(pTHX_ SV *method, U32 *hashp);
static const char * autobox_type(pTHX_ SV * const sv, STRLEN *len);
static void autobox_cleanup(pTHX_ void * unused);
OP * autobox_check_entersub(pTHX_ OP *o);
OP * autobox_method_named(pTHX);
OP * autobox_method(pTHX);
void auto_ref(pTHX_ OP *invocant, UNOP *parent, OP *prev);
#define AUTOBOX_TYPE_RETURN(type) STMT_START { \
*len = (sizeof(type) - 1); return type; \
} STMT_END
static const char *autobox_type(pTHX_ SV * const sv, STRLEN *len) {
switch (SvTYPE(sv)) {
case SVt_NULL:
AUTOBOX_TYPE_RETURN("UNDEF");
case SVt_IV:
/*
* as of perl v5.10.1, references (e.g. \[]), which were previously
* SVt_RV, are now SVt_IV with the SVf_ROK flag set
*/
if (SvROK(sv)) {
AUTOBOX_TYPE_RETURN("REF");
} else {
AUTOBOX_TYPE_RETURN("INTEGER");
}
case SVt_NV:
if (SvIOK(sv) || SvUOK(sv)) { /* XXX not sure this is ever true */
AUTOBOX_TYPE_RETURN("INTEGER");
} else {
AUTOBOX_TYPE_RETURN("FLOAT");
}
case SVt_PVIV:
if (SvIOK(sv) || SvUOK(sv)) {
AUTOBOX_TYPE_RETURN("INTEGER");
} else {
AUTOBOX_TYPE_RETURN("STRING");
}
case SVt_PVNV:
/*
* integer before float:
* https://rt.cpan.org/Ticket/Display.html?id=46814
*/
if (SvIOK(sv) || SvUOK(sv)) {
AUTOBOX_TYPE_RETURN("INTEGER");
} else if (SvNOK(sv)) {
AUTOBOX_TYPE_RETURN("FLOAT");
} else {
AUTOBOX_TYPE_RETURN("STRING");
}
/*
* as of perl v5.10.1, this is an alias for SVt_IV (with the SVf_ROK
* flag set)
*/
#if PERL_BCDVERSION < 0x5010001
case SVt_RV:
#endif
case SVt_PV:
case SVt_PVMG:
#ifdef SvVOK
if (SvVOK(sv)) {
AUTOBOX_TYPE_RETURN("VSTRING");
}
#endif
if (SvROK(sv)) {
AUTOBOX_TYPE_RETURN("REF");
} else {
AUTOBOX_TYPE_RETURN("STRING");
}
/*
* XXX this can actually represent any SV type
*/
case SVt_PVLV:
if (SvROK(sv)) {
AUTOBOX_TYPE_RETURN("REF");
} else if (LvTYPE(sv) == 't' || LvTYPE(sv) == 'T') { /* tied lvalue */
if (SvIOK(sv) || SvUOK(sv)) {
AUTOBOX_TYPE_RETURN("INTEGER");
} else if (SvNOK(sv)) {
AUTOBOX_TYPE_RETURN("FLOAT");
} else {
AUTOBOX_TYPE_RETURN("STRING");
}
} else {
AUTOBOX_TYPE_RETURN("LVALUE");
}
case SVt_PVAV:
AUTOBOX_TYPE_RETURN("ARRAY");
case SVt_PVHV:
AUTOBOX_TYPE_RETURN("HASH");
case SVt_PVCV:
AUTOBOX_TYPE_RETURN("CODE");
case SVt_PVGV:
AUTOBOX_TYPE_RETURN("GLOB");
case SVt_PVFM:
AUTOBOX_TYPE_RETURN("FORMAT");
case SVt_PVIO:
AUTOBOX_TYPE_RETURN("IO");
#ifdef SVt_BIND
case SVt_BIND:
AUTOBOX_TYPE_RETURN("BIND");
#endif
#ifdef SVt_REGEXP
case SVt_REGEXP:
AUTOBOX_TYPE_RETURN("REGEXP");
#endif
default:
AUTOBOX_TYPE_RETURN("UNKNOWN");
}
}
/*
* convert array/hash invocants to arrayref/hashref, e.g.:
*
* @foo->bar -> (\@foo)->bar
*/
void auto_ref(pTHX_ OP *invocant, UNOP *parent, OP *prev) {
#ifndef op_sibling_splice
OP *refgen;
#endif
/*
* perlref:
*
* As a special case, "\(@foo)" returns a list of references to the
* contents of @foo, not a reference to @foo itself. Likewise for %foo,
* except that the key references are to copies (since the keys are just
* strings rather than full-fledged scalars).
*
* we don't want that (it results in the invocant being a reference to the
* last element in the list), so we toggle the parentheses off while creating
* the reference then toggle them back on in case they're needed elsewhere
*
*/
bool toggled = FALSE;
if (invocant->op_flags & OPf_PARENS) {
invocant->op_flags &= ~OPf_PARENS;
toggled = TRUE;
}
#ifdef op_sibling_splice
op_sibling_splice(
(OP *)parent,
prev,
0,
newUNOP(
OP_REFGEN,
0,
op_sibling_splice(
(OP *)parent,
prev,
1,
NULL
)
)
);
#else
/* XXX if this (old?) way works, why do we need both? */
PERL_UNUSED_ARG(parent); /* silence warning on perl v5.8 */
refgen = newUNOP(OP_REFGEN, 0, invocant);
prev->op_sibling = refgen;
refgen->op_sibling = invocant->op_sibling;
invocant->op_sibling = NULL;
#endif
/* Restore the parentheses in case something else expects them */
if (toggled) {
invocant->op_flags |= OPf_PARENS;
}
}
OP * autobox_check_entersub(pTHX_ OP *o) {
UNOP *parent;
OP *prev, *invocant, *cvop;
SV **svp;
HV *hh;
bool has_bindings = FALSE;
/*
* XXX note: perl adopts a convention of calling the OP `o` and has shortcut
* macros based on this convention like cUNOPo, among others. if the name
* changes, the macro will need to change as well e.g. to cUNOPx(op)
*/
/*
* work around a %^H scoping bug by checking that PL_hints (which is
* properly scoped) & an unused PL_hints bit (0x100000) is true
*
* XXX this is fixed in #33311:
*
* https://www.nntp.perl.org/group/perl.perl5.porters/2008/02/msg134131.html
*/
if ((PL_hints & 0x80020000) != 0x80020000) {
goto done;
}
/*
* the OP which yields the CV is the last OP in the ENTERSUB OP's list of
* children. navigate to it by following the `op_sibling` pointers from the
* first child in the list (the invocant)
*/
parent = OpHAS_SIBLING(cUNOPo->op_first) ? cUNOPo : ((UNOP *)cUNOPo->op_first);
prev = parent->op_first;
invocant = OpSIBLING(prev);
for (cvop = invocant; OpHAS_SIBLING(cvop); cvop = OpSIBLING(cvop));
/*
* now we have the CV OP, we can check if it's a method lookup.
* bail out if it's not
*/
if ((cvop->op_type != OP_METHOD) && (cvop->op_type != OP_METHOD_NAMED)) {
goto done;
}
/* bail out if the invocant is a bareword e.g. Foo->bar or Foo->$bar */
if ((invocant->op_type == OP_CONST) && (invocant->op_private & OPpCONST_BARE)) {
goto done;
}
/*
* the bareword flag is not set on the invocants of the `import`, `unimport`
* and `VERSION` methods faked up by `use` and `no` [1]. we have no other way
* to detect if an OP_CONST invocant is a bareword for these methods,
* so we have no choice but to assume it is and bail out so that we don't
* break `use`, `no` etc.
*
* (this is documented: the solution/workaround is to use
* $native->autobox_class instead.)
*
* note: we exempt all invocant types from these methods rather than just
* the invocants we can't be sure about (i.e. OP_CONST). we *could* allow
* e.g. []->VERSION or {}->import, but we don't, for consistency. even if
* OP_CONST invocants had the correct bareword flags, it's far more likely
* to be a bug for e.g. []->VERSION to differ from ARRAY->VERSION than
* a deliberate feature. [2]
*
* likewise, we also exempt $native->can and $native->isa here, neither
* of which are well-defined as instance methods.
*
* [1] XXX this is a bug (in perl)
*
* [2] although if these barewords did have the correct flag, we could
* forward (non-bareword) calls to these methods to autobox_class
* automatically rather than requiring the user to do it manually
*/
if (cvop->op_type == OP_METHOD_NAMED) {
/* SvPVX_const should be sane for the method name */
const char * method_name = SvPVX_const(((SVOP *)cvop)->op_sv);
if (
strEQ(method_name, "can") ||
strEQ(method_name, "DOES") ||
strEQ(method_name, "import") ||
strEQ(method_name, "isa") ||
strEQ(method_name, "unimport") ||
strEQ(method_name, "VERSION")
) {
goto done;
}
}
hh = GvHV(PL_hintgv); /* the hints hash (%^H) */
/* is there a bindings hashref for this scope? */
has_bindings = hh
&& (svp = hv_fetch(hh, "autobox", 7, FALSE))
&& *svp
&& SvROK(*svp);
if (!has_bindings) {
goto done;
}
/*
* if the invocant is an @array, %hash, @{ ... } or %{ ... }, then
* "auto-ref" it, i.e. the optree equivalent of inserting a backslash
* before it:
*
* @foo->bar -> (\@foo)->bar
*/
switch (invocant->op_type) {
case OP_PADAV:
case OP_PADHV:
case OP_RV2AV:
case OP_RV2HV:
auto_ref(aTHX_ invocant, parent, prev);
}
cvop->op_flags |= OPf_SPECIAL;
cvop->op_ppaddr = cvop->op_type == OP_METHOD
? autobox_method
: autobox_method_named;
PTABLE_store(AUTOBOX_OP_MAP, cvop, SvRV(*svp));
done:
return autobox_old_check_entersub(aTHX_ o);
}
/* returns either the method, or NULL, meaning delegate to the original op */
static SV * autobox_method_common(pTHX_ SV * method, U32* hashp) {
SV * const invocant = *(PL_stack_base + TOPMARK + 1);
SV * packsv;
HV * autobox_bindings;
HV * stash;
const char * reftype; /* autobox_bindings key */
SV **svp; /* pointer to autobox_bindings value */
STRLEN typelen = 0, packlen = 0;
const char * packname;
GV * gv;
/* if autobox isn't enabled (in scope) for this op, bail out */
if (!(PL_op->op_flags & OPf_SPECIAL)) {
return NULL;
}
/*
* bail out if the invocant is NULL (not to be confused with undef), e.g.
* from a buggy XS module
*/
if (!invocant) {
return NULL;
}
/*
* if the invocant's an object (blessed reference), bail out.
*
* XXX don't use sv_isobject - we don't want to call SvGETMAGIC twice
*/
if (SvROK(invocant) && SvOBJECT(SvRV(invocant))) {
return NULL;
}
/* XXX do non-objects have magic attached? */
SvGETMAGIC(invocant);
/* the "bindings hash", which maps the names of native types to package names */
autobox_bindings = (HV *)(PTABLE_fetch(AUTOBOX_OP_MAP, PL_op));
if (!autobox_bindings) {
return NULL;
}
/*
* the type is either the invocant's reftype(), a subtype of
* SCALAR if it's not a ref, or UNDEF if it's not defined
*/
if (SvOK(invocant)) {
reftype = autobox_type(
aTHX_ (SvROK(invocant) ? SvRV(invocant) : invocant),
&typelen
);
} else {
reftype = "UNDEF";
typelen = sizeof("UNDEF") - 1;
}
svp = hv_fetch(autobox_bindings, reftype, typelen, 0);
if (!(svp && SvOK(*svp))) {
return NULL;
}
packsv = *svp;
packname = SvPV_const(packsv, packlen);
stash = gv_stashpvn(packname, packlen, FALSE);
if (hashp) { /* shortcut for simple names */
const HE * const he = hv_fetch_ent(stash, method, 0, *hashp);
if (he) {
U32 cvgen;
#ifdef HvMROMETA /* introduced in v5.10 */
cvgen = PL_sub_generation + HvMROMETA(stash)->cache_gen;
#else
cvgen = PL_sub_generation;
#endif
gv = MUTABLE_GV(HeVAL(he));
/*
* GvCVGEN(gv) is almost always 0, so the global and local cache
* invalidation (above) seldom comes into play
*/
if (isGV(gv) && GvCV(gv) && (!GvCVGEN(gv) || GvCVGEN(gv) == cvgen)) {
return MUTABLE_SV(GvCV(gv));
}
}
}
/*
* SvPV_nolen_const returns the method name as a const char *,
* stringifying names that are not strings (e.g. undef, SvIV,
* SvNV etc.) - see name.t
*/
gv = gv_fetchmethod(
stash ? stash : (HV*)packsv,
SvPV_nolen_const(method)
);
if (gv) {
return isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv);
}
return NULL;
}
OP* autobox_method(pTHX) {
dVAR; dSP;
SV * const sv = TOPs;
SV * cv;
if (SvROK(sv)) {
cv = SvRV(sv);
if (SvTYPE(cv) == SVt_PVCV) {
SETs(cv);
RETURN;
}
}
cv = autobox_method_common(aTHX_ sv, NULL);
if (cv) {
SETs(cv);
RETURN;
} else {
return PL_ppaddr[OP_METHOD](aTHXR);
}
}
OP* autobox_method_named(pTHX) {
dVAR; dSP;
SV * const sv = cSVOP_sv;
U32 hash = SvSHARED_HASH(sv);
SV * cv;
cv = autobox_method_common(aTHX_ sv, &hash);
if (cv) {
XPUSHs(cv);
RETURN;
} else {
return PL_ppaddr[OP_METHOD_NAMED](aTHXR);
}
}
static void autobox_cleanup(pTHX_ void * unused) {
PERL_UNUSED_ARG(unused); /* silence warning on perl v5.8 */
if (AUTOBOX_OP_MAP) {
PTABLE_free(AUTOBOX_OP_MAP);
AUTOBOX_OP_MAP = NULL;
}
}
MODULE = autobox PACKAGE = autobox
PROTOTYPES: ENABLE
BOOT:
/*
* XXX the BOOT section extends to the next blank line, so don't add one
* for readability
*/
PERL_UNUSED_ARG(cv); /* silence warning on perl v5.8 */
AUTOBOX_OP_MAP = PTABLE_new();
if (AUTOBOX_OP_MAP) {
Perl_call_atexit(aTHX_ autobox_cleanup, NULL);
} else {
Perl_croak(aTHX_ "Can't initialize OP map");
}
void
_enter()
PROTOTYPE:
CODE:
PERL_UNUSED_ARG(cv); /* silence warning on perl v5.8 */
if (AUTOBOX_SCOPE_DEPTH > 0) {
++AUTOBOX_SCOPE_DEPTH;
} else {
AUTOBOX_SCOPE_DEPTH = 1;
/*
* capture the check routine in scope when autobox is used.
* usually, this will be Perl_ck_subr, though, in principle,
* it could be a bespoke checker spliced in by another module.
*/
autobox_old_check_entersub = PL_check[OP_ENTERSUB];
PL_check[OP_ENTERSUB] = autobox_check_entersub;
}
void
_leave()
PROTOTYPE:
CODE:
PERL_UNUSED_ARG(cv); /* silence warning on perl v5.8 */
if (AUTOBOX_SCOPE_DEPTH == 0) {
Perl_warn(aTHX_ "scope underflow");
}
if (AUTOBOX_SCOPE_DEPTH > 1) {
--AUTOBOX_SCOPE_DEPTH;
} else {
AUTOBOX_SCOPE_DEPTH = 0;
PL_check[OP_ENTERSUB] = autobox_old_check_entersub;
}
void
_scope()
PROTOTYPE:
CODE:
PERL_UNUSED_ARG(cv); /* silence warning on perl v5.8 */
XSRETURN_UV(PTR2UV(GvHV(PL_hintgv)));
MODULE = autobox PACKAGE = autobox::universal
SV *
type(SV * sv)
PROTOTYPE:$
PREINIT:
STRLEN len = 0;
const char *type;
CODE:
PERL_UNUSED_ARG(cv); /* silence warning on perl v5.8 */
if (SvOK(sv)) {
type = autobox_type(aTHX_ (SvROK(sv) ? SvRV(sv) : sv), &len);
RETVAL = newSVpv(type, len);
} else {
RETVAL = newSVpv("UNDEF", sizeof("UNDEF") - 1);
}
OUTPUT:
RETVAL