[perl5.git] / cv.h

/*    cv.h
 *
 *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001,
 *    2002, 2003, 2004, 2005, 2006, 2007, 2008 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.
 *
 */

/* This structure must match the beginning of XPVFM in sv.h  */

struct xpvcv {
    _XPV_HEAD;
    _XPVCV_COMMON;
};

/*
=head1 Handy Values

=for apidoc AmU||Nullcv
Null CV pointer.

(deprecated - use C<(CV *)NULL> instead)

=head1 CV Manipulation Functions

This section documents functions to manipulate CVs which are code-values,
or subroutines.  For more information, see L<perlguts>.

=for apidoc Am|HV*|CvSTASH|CV* cv
Returns the stash of the CV.  A stash is the symbol table hash, containing
the package-scoped variables in the package where the subroutine was defined.
For more information, see L<perlguts>.

This also has a special use with XS AUTOLOAD subs.
See L<perlguts/Autoloading with XSUBs>.

=cut
*/

#ifndef PERL_CORE
#  define Nullcv Null(CV*)
#endif

#define CvSTASH(sv)	(0+((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_stash)
#define CvSTASH_set(cv,st) Perl_cvstash_set(aTHX_ cv, st)
#define CvSTART(sv)	((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_start_u.xcv_start
#define CvROOT(sv)	((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_root_u.xcv_root
#define CvXSUB(sv)	((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_root_u.xcv_xsub
#define CvXSUBANY(sv)	((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_start_u.xcv_xsubany
#define CvGV(sv)	S_CvGV(aTHX_ (CV *)(sv))
#define CvGV_set(cv,gv)	Perl_cvgv_set(aTHX_ cv, gv)
#define CvHASGV(cv)	cBOOL(SvANY(cv)->xcv_gv_u.xcv_gv)
#define CvFILE(sv)	((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_file
#ifdef USE_ITHREADS
#  define CvFILE_set_from_cop(sv, cop)	\
    (CvFILE(sv) = savepv(CopFILE(cop)), CvDYNFILE_on(sv))
#else
#  define CvFILE_set_from_cop(sv, cop)	\
    (CvFILE(sv) = CopFILE(cop), CvDYNFILE_off(sv))
#endif
#define CvFILEGV(sv)	(gv_fetchfile(CvFILE(sv)))
#define CvDEPTH(sv)	(*S_CvDEPTHp((const CV *)sv))
/* For use when you only have a XPVCV*, not a real CV*.
   Must be assert protected as in S_CvDEPTHp before use. */
#define CvDEPTHunsafe(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_depth

/* these CvPADLIST/CvRESERVED asserts can be reverted one day, once stabilized */
#define CvPADLIST(sv)	  (*(assert_(!CvISXSUB((CV*)(sv))) \
	&(((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist)))
/* CvPADLIST_set is not public API, it can be removed one day, once stabilized */
#ifdef DEBUGGING
#  define CvPADLIST_set(sv, padlist) Perl_set_padlist((CV*)sv, padlist)
#else
#  define CvPADLIST_set(sv, padlist) (CvPADLIST(sv) = (padlist))
#endif
#define CvHSCXT(sv)	  *(assert_(CvISXSUB((CV*)(sv))) \
	&(((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_hscxt))
#ifdef DEBUGGING
#  if PTRSIZE == 8
#    define PoisonPADLIST(sv) \
        (((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist = (PADLIST *)UINT64_C(0xEFEFEFEFEFEFEFEF))
#  elif PTRSIZE == 4
#    define PoisonPADLIST(sv) \
        (((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist = (PADLIST *)0xEFEFEFEF)
#  else
#    error unknown pointer size
#  endif
#else
#  define PoisonPADLIST(sv) NOOP
#endif

#define CvOUTSIDE(sv)	  ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside
#define CvOUTSIDE_SEQ(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside_seq
#define CvFLAGS(sv)	  ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_flags

/* These two are sometimes called on non-CVs */
#define CvPROTO(sv)                               \
	(                                          \
	 SvPOK(sv)                                  \
	  ? SvTYPE(sv) == SVt_PVCV && CvAUTOLOAD(sv) \
	     ? SvEND(sv)+1 : SvPVX_const(sv)          \
	  : NULL                                       \
	)
#define CvPROTOLEN(sv)	                          \
	(                                          \
	 SvPOK(sv)                                  \
	  ? SvTYPE(sv) == SVt_PVCV && CvAUTOLOAD(sv) \
	     ? SvLEN(sv)-SvCUR(sv)-2                  \
	     : SvCUR(sv)                               \
	  : 0                                           \
	)

#define CVf_METHOD	0x0001	/* CV is explicitly marked as a method */
#define CVf_LVALUE	0x0002  /* CV return value can be used as lvalue */
#define CVf_CONST	0x0004  /* inlinable sub */
#define CVf_ISXSUB	0x0008	/* CV is an XSUB, not pure perl.  */

#define CVf_WEAKOUTSIDE	0x0010  /* CvOUTSIDE isn't ref counted */
#define CVf_CLONE	0x0020	/* anon CV uses external lexicals */
#define CVf_CLONED	0x0040	/* a clone of one of those */
#define CVf_ANON	0x0080	/* CV is not pointed to by a GV */
#define CVf_UNIQUE	0x0100	/* sub is only called once (eg PL_main_cv,
				 * require, eval). */
#define CVf_NODEBUG	0x0200	/* no DB::sub indirection for this CV
				   (esp. useful for special XSUBs) */
#define CVf_CVGV_RC	0x0400	/* CvGV is reference counted */
#ifdef PERL_CORE
# define CVf_SLABBED	0x0800	/* Holds refcount on op slab  */
#endif
#define CVf_DYNFILE	0x1000	/* The filename isn't static  */
#define CVf_AUTOLOAD	0x2000	/* SvPVX contains AUTOLOADed sub name  */
#define CVf_HASEVAL	0x4000	/* contains string eval  */
#define CVf_NAMED	0x8000  /* Has a name HEK */
#define CVf_LEXICAL	0x10000 /* Omit package from name */

/* This symbol for optimised communication between toke.c and op.c: */
#define CVf_BUILTIN_ATTRS	(CVf_METHOD|CVf_LVALUE)

#define CvCLONE(cv)		(CvFLAGS(cv) & CVf_CLONE)
#define CvCLONE_on(cv)		(CvFLAGS(cv) |= CVf_CLONE)
#define CvCLONE_off(cv)		(CvFLAGS(cv) &= ~CVf_CLONE)

#define CvCLONED(cv)		(CvFLAGS(cv) & CVf_CLONED)
#define CvCLONED_on(cv)		(CvFLAGS(cv) |= CVf_CLONED)
#define CvCLONED_off(cv)	(CvFLAGS(cv) &= ~CVf_CLONED)

#define CvANON(cv)		(CvFLAGS(cv) & CVf_ANON)
#define CvANON_on(cv)		(CvFLAGS(cv) |= CVf_ANON)
#define CvANON_off(cv)		(CvFLAGS(cv) &= ~CVf_ANON)

/* CvEVAL or CvSPECIAL */
#define CvUNIQUE(cv)		(CvFLAGS(cv) & CVf_UNIQUE)
#define CvUNIQUE_on(cv)		(CvFLAGS(cv) |= CVf_UNIQUE)
#define CvUNIQUE_off(cv)	(CvFLAGS(cv) &= ~CVf_UNIQUE)

#define CvNODEBUG(cv)		(CvFLAGS(cv) & CVf_NODEBUG)
#define CvNODEBUG_on(cv)	(CvFLAGS(cv) |= CVf_NODEBUG)
#define CvNODEBUG_off(cv)	(CvFLAGS(cv) &= ~CVf_NODEBUG)

#define CvMETHOD(cv)		(CvFLAGS(cv) & CVf_METHOD)
#define CvMETHOD_on(cv)		(CvFLAGS(cv) |= CVf_METHOD)
#define CvMETHOD_off(cv)	(CvFLAGS(cv) &= ~CVf_METHOD)

#define CvLVALUE(cv)		(CvFLAGS(cv) & CVf_LVALUE)
#define CvLVALUE_on(cv)		(CvFLAGS(cv) |= CVf_LVALUE)
#define CvLVALUE_off(cv)	(CvFLAGS(cv) &= ~CVf_LVALUE)

/* eval or PL_main_cv */
#define CvEVAL(cv)		(CvUNIQUE(cv) && !SvFAKE(cv))
#define CvEVAL_on(cv)		(CvUNIQUE_on(cv),SvFAKE_off(cv))
#define CvEVAL_off(cv)		CvUNIQUE_off(cv)

/* BEGIN|CHECK|INIT|UNITCHECK|END */
#define CvSPECIAL(cv)		(CvUNIQUE(cv) && SvFAKE(cv))
#define CvSPECIAL_on(cv)	(CvUNIQUE_on(cv),SvFAKE_on(cv))
#define CvSPECIAL_off(cv)	(CvUNIQUE_off(cv),SvFAKE_off(cv))

#define CvCONST(cv)		(CvFLAGS(cv) & CVf_CONST)
#define CvCONST_on(cv)		(CvFLAGS(cv) |= CVf_CONST)
#define CvCONST_off(cv)		(CvFLAGS(cv) &= ~CVf_CONST)

#define CvWEAKOUTSIDE(cv)	(CvFLAGS(cv) & CVf_WEAKOUTSIDE)
#define CvWEAKOUTSIDE_on(cv)	(CvFLAGS(cv) |= CVf_WEAKOUTSIDE)
#define CvWEAKOUTSIDE_off(cv)	(CvFLAGS(cv) &= ~CVf_WEAKOUTSIDE)

#define CvISXSUB(cv)		(CvFLAGS(cv) & CVf_ISXSUB)
#define CvISXSUB_on(cv)		(CvFLAGS(cv) |= CVf_ISXSUB)
#define CvISXSUB_off(cv)	(CvFLAGS(cv) &= ~CVf_ISXSUB)

#define CvCVGV_RC(cv)		(CvFLAGS(cv) & CVf_CVGV_RC)
#define CvCVGV_RC_on(cv)	(CvFLAGS(cv) |= CVf_CVGV_RC)
#define CvCVGV_RC_off(cv)	(CvFLAGS(cv) &= ~CVf_CVGV_RC)

#ifdef PERL_CORE
# define CvSLABBED(cv)		(CvFLAGS(cv) & CVf_SLABBED)
# define CvSLABBED_on(cv)	(CvFLAGS(cv) |= CVf_SLABBED)
# define CvSLABBED_off(cv)	(CvFLAGS(cv) &= ~CVf_SLABBED)
#endif

#define CvDYNFILE(cv)		(CvFLAGS(cv) & CVf_DYNFILE)
#define CvDYNFILE_on(cv)	(CvFLAGS(cv) |= CVf_DYNFILE)
#define CvDYNFILE_off(cv)	(CvFLAGS(cv) &= ~CVf_DYNFILE)

#define CvAUTOLOAD(cv)		(CvFLAGS(cv) & CVf_AUTOLOAD)
#define CvAUTOLOAD_on(cv)	(CvFLAGS(cv) |= CVf_AUTOLOAD)
#define CvAUTOLOAD_off(cv)	(CvFLAGS(cv) &= ~CVf_AUTOLOAD)

#define CvHASEVAL(cv)		(CvFLAGS(cv) & CVf_HASEVAL)
#define CvHASEVAL_on(cv)	(CvFLAGS(cv) |= CVf_HASEVAL)
#define CvHASEVAL_off(cv)	(CvFLAGS(cv) &= ~CVf_HASEVAL)

#define CvNAMED(cv)		(CvFLAGS(cv) & CVf_NAMED)
#define CvNAMED_on(cv)		(CvFLAGS(cv) |= CVf_NAMED)
#define CvNAMED_off(cv)		(CvFLAGS(cv) &= ~CVf_NAMED)

#define CvLEXICAL(cv)		(CvFLAGS(cv) & CVf_LEXICAL)
#define CvLEXICAL_on(cv)	(CvFLAGS(cv) |= CVf_LEXICAL)
#define CvLEXICAL_off(cv)	(CvFLAGS(cv) &= ~CVf_LEXICAL)

/* Flags for newXS_flags  */
#define XS_DYNAMIC_FILENAME	0x01	/* The filename isn't static  */

PERL_STATIC_INLINE HEK *
CvNAME_HEK(CV *sv)
{
    return CvNAMED(sv)
	? ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_gv_u.xcv_hek
	: 0;
}
/* This lowers the refernce count of the previous value, but does *not*
   increment the reference count of the new value. */
#define CvNAME_HEK_set(cv, hek) ( \
	CvNAME_HEK((CV *)(cv))						 \
	    ? unshare_hek(SvANY((CV *)(cv))->xcv_gv_u.xcv_hek)	  \
	    : (void)0,						   \
	((XPVCV*)MUTABLE_PTR(SvANY(cv)))->xcv_gv_u.xcv_hek = (hek), \
	CvNAMED_on(cv)						     \
    )

/*
=head1 CV reference counts and CvOUTSIDE

=for apidoc m|bool|CvWEAKOUTSIDE|CV *cv

Each CV has a pointer, C<CvOUTSIDE()>, to its lexically enclosing
CV (if any).  Because pointers to anonymous sub prototypes are
stored in C<&> pad slots, it is a possible to get a circular reference,
with the parent pointing to the child and vice-versa.  To avoid the
ensuing memory leak, we do not increment the reference count of the CV
pointed to by C<CvOUTSIDE> in the I<one specific instance> that the parent
has a C<&> pad slot pointing back to us.  In this case, we set the
C<CvWEAKOUTSIDE> flag in the child.  This allows us to determine under what
circumstances we should decrement the refcount of the parent when freeing
the child.

There is a further complication with non-closure anonymous subs (i.e. those
that do not refer to any lexicals outside that sub).  In this case, the
anonymous prototype is shared rather than being cloned.  This has the
consequence that the parent may be freed while there are still active
children, eg

    BEGIN { $a = sub { eval '$x' } }

In this case, the BEGIN is freed immediately after execution since there
are no active references to it: the anon sub prototype has
C<CvWEAKOUTSIDE> set since it's not a closure, and $a points to the same
CV, so it doesn't contribute to BEGIN's refcount either.  When $a is
executed, the C<eval '$x'> causes the chain of C<CvOUTSIDE>s to be followed,
and the freed BEGIN is accessed.

To avoid this, whenever a CV and its associated pad is freed, any
C<&> entries in the pad are explicitly removed from the pad, and if the
refcount of the pointed-to anon sub is still positive, then that
child's C<CvOUTSIDE> is set to point to its grandparent.  This will only
occur in the single specific case of a non-closure anon prototype
having one or more active references (such as C<$a> above).

One other thing to consider is that a CV may be merely undefined
rather than freed, eg C<undef &foo>.  In this case, its refcount may
not have reached zero, but we still delete its pad and its C<CvROOT> etc.
Since various children may still have their C<CvOUTSIDE> pointing at this
undefined CV, we keep its own C<CvOUTSIDE> for the time being, so that
the chain of lexical scopes is unbroken.  For example, the following
should print 123:

    my $x = 123;
    sub tmp { sub { eval '$x' } }
    my $a = tmp();
    undef &tmp;
    print  $a->();

=cut
*/

typedef OP *(*Perl_call_checker)(pTHX_ OP *, GV *, SV *);

#define CALL_CHECKER_REQUIRE_GV	MGf_REQUIRE_GV

#define CV_NAME_NOTQUAL		1

#ifdef PERL_CORE
# define CV_UNDEF_KEEP_NAME	1
#endif

/*
 * Local variables:
 * c-indentation-style: bsd
 * c-basic-offset: 4
 * indent-tabs-mode: nil
 * End:
 *
 * ex: set ts=8 sts=4 sw=4 et:
 */
Commit	Line	Data
a0d0e21e	1	/* cv.h
79072805	2	*
1129b882 NC	3	* Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001,
1129b882 NC	4	* 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
79072805 LW	5	*
	6	* You may distribute under the terms of either the GNU General Public
	7	* License or the Artistic License, as specified in the README file.
	8	*
79072805 LW	9	*/
79072805 LW	10
f653aab7	11	/* This structure must match the beginning of XPVFM in sv.h */
44a8e56a	12
79072805	13	struct xpvcv {
20f4945e	14	_XPV_HEAD;
20f4945e	15	_XPVCV_COMMON;
79072805	16	};
748a9306	17
954c1994	18	/*
ccfc67b7 JH	19	=head1 Handy Values
ccfc67b7 JH	20
954c1994 GS	21	=for apidoc AmU\|\|Nullcv
	22	Null CV pointer.
	23
3ae1b226 NC	24	(deprecated - use C<(CV *)NULL> instead)
3ae1b226 NC	25
ccfc67b7 JH	26	=head1 CV Manipulation Functions
ccfc67b7 JH	27
f0b90de1	28	This section documents functions to manipulate CVs which are code-values,
154e47c8	29	or subroutines. For more information, see L<perlguts>.
f0b90de1	30
954c1994	31	=for apidoc Am\|HV\|CvSTASH\|CV cv
72d33970	32	Returns the stash of the CV. A stash is the symbol table hash, containing
f0b90de1 SF	33	the package-scoped variables in the package where the subroutine was defined.
f0b90de1 SF	34	For more information, see L<perlguts>.
954c1994	35
5b36e945 FC	36	This also has a special use with XS AUTOLOAD subs.
	37	See L<perlguts/Autoloading with XSUBs>.
	38
954c1994 GS	39	=cut
	40	*/
	41
3ae1b226 NC	42	#ifndef PERL_CORE
	43	# define Nullcv Null(CV*)
	44	#endif
a5f75d66	45
c68d9564 Z	46	#define CvSTASH(sv) (0+((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_stash)
c68d9564 Z	47	#define CvSTASH_set(cv,st) Perl_cvstash_set(aTHX_ cv, st)
8f629a87 NC	48	#define CvSTART(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_start_u.xcv_start
	49	#define CvROOT(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_root_u.xcv_root
	50	#define CvXSUB(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_root_u.xcv_xsub
	51	#define CvXSUBANY(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_start_u.xcv_xsubany
ae77754a	52	#define CvGV(sv) S_CvGV(aTHX_ (CV *)(sv))
b3f91e91	53	#define CvGV_set(cv,gv) Perl_cvgv_set(aTHX_ cv, gv)
ae77754a	54	#define CvHASGV(cv) cBOOL(SvANY(cv)->xcv_gv_u.xcv_gv)
8f629a87	55	#define CvFILE(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_file
a636914a	56	#ifdef USE_ITHREADS
bad4ae38 FC	57	# define CvFILE_set_from_cop(sv, cop) \
bad4ae38 FC	58	(CvFILE(sv) = savepv(CopFILE(cop)), CvDYNFILE_on(sv))
a636914a	59	#else
bad4ae38 FC	60	# define CvFILE_set_from_cop(sv, cop) \
bad4ae38 FC	61	(CvFILE(sv) = CopFILE(cop), CvDYNFILE_off(sv))
a636914a	62	#endif
9ec2a764	63	#define CvFILEGV(sv) (gv_fetchfile(CvFILE(sv)))
1afe1db1	64	#define CvDEPTH(sv) (S_CvDEPTHp((const CV )sv))
52ec28d5 DD	65	/* For use when you only have a XPVCV, not a real CV.
	66	Must be assert protected as in S_CvDEPTHp before use. */
	67	#define CvDEPTHunsafe(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_depth
eacbb379 DD	68
	69	/* these CvPADLIST/CvRESERVED asserts can be reverted one day, once stabilized */
	70	#define CvPADLIST(sv) ((assert_(!CvISXSUB((CV)(sv))) \
	71	&(((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist)))
	72	/* CvPADLIST_set is not public API, it can be removed one day, once stabilized */
	73	#ifdef DEBUGGING
e69651e7	74	# define CvPADLIST_set(sv, padlist) Perl_set_padlist((CV*)sv, padlist)
eacbb379 DD	75	#else
	76	# define CvPADLIST_set(sv, padlist) (CvPADLIST(sv) = (padlist))
	77	#endif
db6e00bd DD	78	#define CvHSCXT(sv) (assert_(CvISXSUB((CV)(sv))) \
db6e00bd DD	79	&(((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_hscxt))
eacbb379 DD	80	#ifdef DEBUGGING
	81	# if PTRSIZE == 8
	82	# define PoisonPADLIST(sv) \
	83	(((XPVCV)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist = (PADLIST )UINT64_C(0xEFEFEFEFEFEFEFEF))
	84	# elif PTRSIZE == 4
	85	# define PoisonPADLIST(sv) \
	86	(((XPVCV)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist = (PADLIST )0xEFEFEFEF)
	87	# else
	88	# error unknown pointer size
	89	# endif
	90	#else
eba7d13f	91	# define PoisonPADLIST(sv) NOOP
eacbb379 DD	92	#endif
eacbb379 DD	93
52ec28d5	94	#define CvOUTSIDE(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside
8f629a87	95	#define CvOUTSIDE_SEQ(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside_seq
52ec28d5	96	#define CvFLAGS(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_flags
a5f75d66	97
8fa6a409 FC	98	/* These two are sometimes called on non-CVs */
	99	#define CvPROTO(sv) \
	100	( \
	101	SvPOK(sv) \
	102	? SvTYPE(sv) == SVt_PVCV && CvAUTOLOAD(sv) \
	103	? SvEND(sv)+1 : SvPVX_const(sv) \
	104	: NULL \
	105	)
	106	#define CvPROTOLEN(sv) \
	107	( \
	108	SvPOK(sv) \
	109	? SvTYPE(sv) == SVt_PVCV && CvAUTOLOAD(sv) \
	110	? SvLEN(sv)-SvCUR(sv)-2 \
	111	: SvCUR(sv) \
	112	: 0 \
	113	)
	114
5b4563c8	115	#define CVf_METHOD 0x0001 /* CV is explicitly marked as a method */
c2485e0c NC	116	#define CVf_LVALUE 0x0002 /* CV return value can be used as lvalue */
	117	#define CVf_CONST 0x0004 /* inlinable sub */
	118	#define CVf_ISXSUB 0x0008 /* CV is an XSUB, not pure perl. */
5b4563c8 NC	119
	120	#define CVf_WEAKOUTSIDE 0x0010 /* CvOUTSIDE isn't ref counted */
	121	#define CVf_CLONE 0x0020 /* anon CV uses external lexicals */
	122	#define CVf_CLONED 0x0040 /* a clone of one of those */
cfc1e951	123	#define CVf_ANON 0x0080 /* CV is not pointed to by a GV */
5b4563c8	124	#define CVf_UNIQUE 0x0100 /* sub is only called once (eg PL_main_cv,
1108974d	125	* require, eval). */
5b4563c8	126	#define CVf_NODEBUG 0x0200 /* no DB::sub indirection for this CV
8ebc5c01	127	(esp. useful for special XSUBs) */
cfc1e951	128	#define CVf_CVGV_RC 0x0400 /* CvGV is reference counted */
58aef2b3 FC	129	#ifdef PERL_CORE
	130	# define CVf_SLABBED 0x0800 /* Holds refcount on op slab */
	131	#endif
bad4ae38	132	#define CVf_DYNFILE 0x1000 /* The filename isn't static */
8fa6a409	133	#define CVf_AUTOLOAD 0x2000 /* SvPVX contains AUTOLOADed sub name */
a0d2bbd5	134	#define CVf_HASEVAL 0x4000 /* contains string eval */
b290562e	135	#define CVf_NAMED 0x8000 /* Has a name HEK */
5bb151a5	136	#define CVf_LEXICAL 0x10000 /* Omit package from name */
7dafbf52	137
d3cea301	138	/* This symbol for optimised communication between toke.c and op.c: */
e95ab0c0	139	#define CVf_BUILTIN_ATTRS (CVf_METHOD\|CVf_LVALUE)
a5f75d66 AD	140
	141	#define CvCLONE(cv) (CvFLAGS(cv) & CVf_CLONE)
	142	#define CvCLONE_on(cv) (CvFLAGS(cv) \|= CVf_CLONE)
	143	#define CvCLONE_off(cv) (CvFLAGS(cv) &= ~CVf_CLONE)
	144
	145	#define CvCLONED(cv) (CvFLAGS(cv) & CVf_CLONED)
	146	#define CvCLONED_on(cv) (CvFLAGS(cv) \|= CVf_CLONED)
	147	#define CvCLONED_off(cv) (CvFLAGS(cv) &= ~CVf_CLONED)
	148
	149	#define CvANON(cv) (CvFLAGS(cv) & CVf_ANON)
	150	#define CvANON_on(cv) (CvFLAGS(cv) \|= CVf_ANON)
	151	#define CvANON_off(cv) (CvFLAGS(cv) &= ~CVf_ANON)
79072805	152
a2278b6a	153	/* CvEVAL or CvSPECIAL */
07055b4c CS	154	#define CvUNIQUE(cv) (CvFLAGS(cv) & CVf_UNIQUE)
	155	#define CvUNIQUE_on(cv) (CvFLAGS(cv) \|= CVf_UNIQUE)
	156	#define CvUNIQUE_off(cv) (CvFLAGS(cv) &= ~CVf_UNIQUE)
8ebc5c01	157
	158	#define CvNODEBUG(cv) (CvFLAGS(cv) & CVf_NODEBUG)
	159	#define CvNODEBUG_on(cv) (CvFLAGS(cv) \|= CVf_NODEBUG)
	160	#define CvNODEBUG_off(cv) (CvFLAGS(cv) &= ~CVf_NODEBUG)
77a005ab MB	161
	162	#define CvMETHOD(cv) (CvFLAGS(cv) & CVf_METHOD)
	163	#define CvMETHOD_on(cv) (CvFLAGS(cv) \|= CVf_METHOD)
	164	#define CvMETHOD_off(cv) (CvFLAGS(cv) &= ~CVf_METHOD)
	165
cd06dffe GS	166	#define CvLVALUE(cv) (CvFLAGS(cv) & CVf_LVALUE)
	167	#define CvLVALUE_on(cv) (CvFLAGS(cv) \|= CVf_LVALUE)
	168	#define CvLVALUE_off(cv) (CvFLAGS(cv) &= ~CVf_LVALUE)
	169
a2278b6a	170	/* eval or PL_main_cv */
1aff0e91 GS	171	#define CvEVAL(cv) (CvUNIQUE(cv) && !SvFAKE(cv))
	172	#define CvEVAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_off(cv))
	173	#define CvEVAL_off(cv) CvUNIQUE_off(cv)
	174
3c10abe3	175	/* BEGIN\|CHECK\|INIT\|UNITCHECK\|END */
1aff0e91 GS	176	#define CvSPECIAL(cv) (CvUNIQUE(cv) && SvFAKE(cv))
	177	#define CvSPECIAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_on(cv))
	178	#define CvSPECIAL_off(cv) (CvUNIQUE_off(cv),SvFAKE_off(cv))
beab0874 JT	179
	180	#define CvCONST(cv) (CvFLAGS(cv) & CVf_CONST)
	181	#define CvCONST_on(cv) (CvFLAGS(cv) \|= CVf_CONST)
	182	#define CvCONST_off(cv) (CvFLAGS(cv) &= ~CVf_CONST)
a4f1a029	183
7dafbf52 DM	184	#define CvWEAKOUTSIDE(cv) (CvFLAGS(cv) & CVf_WEAKOUTSIDE)
	185	#define CvWEAKOUTSIDE_on(cv) (CvFLAGS(cv) \|= CVf_WEAKOUTSIDE)
	186	#define CvWEAKOUTSIDE_off(cv) (CvFLAGS(cv) &= ~CVf_WEAKOUTSIDE)
	187
d04ba589 NC	188	#define CvISXSUB(cv) (CvFLAGS(cv) & CVf_ISXSUB)
	189	#define CvISXSUB_on(cv) (CvFLAGS(cv) \|= CVf_ISXSUB)
	190	#define CvISXSUB_off(cv) (CvFLAGS(cv) &= ~CVf_ISXSUB)
	191
cfc1e951 DM	192	#define CvCVGV_RC(cv) (CvFLAGS(cv) & CVf_CVGV_RC)
	193	#define CvCVGV_RC_on(cv) (CvFLAGS(cv) \|= CVf_CVGV_RC)
	194	#define CvCVGV_RC_off(cv) (CvFLAGS(cv) &= ~CVf_CVGV_RC)
	195
58aef2b3 FC	196	#ifdef PERL_CORE
	197	# define CvSLABBED(cv) (CvFLAGS(cv) & CVf_SLABBED)
	198	# define CvSLABBED_on(cv) (CvFLAGS(cv) \|= CVf_SLABBED)
	199	# define CvSLABBED_off(cv) (CvFLAGS(cv) &= ~CVf_SLABBED)
	200	#endif
	201
bad4ae38 FC	202	#define CvDYNFILE(cv) (CvFLAGS(cv) & CVf_DYNFILE)
	203	#define CvDYNFILE_on(cv) (CvFLAGS(cv) \|= CVf_DYNFILE)
	204	#define CvDYNFILE_off(cv) (CvFLAGS(cv) &= ~CVf_DYNFILE)
	205
8fa6a409 FC	206	#define CvAUTOLOAD(cv) (CvFLAGS(cv) & CVf_AUTOLOAD)
	207	#define CvAUTOLOAD_on(cv) (CvFLAGS(cv) \|= CVf_AUTOLOAD)
	208	#define CvAUTOLOAD_off(cv) (CvFLAGS(cv) &= ~CVf_AUTOLOAD)
	209
a0d2bbd5 FC	210	#define CvHASEVAL(cv) (CvFLAGS(cv) & CVf_HASEVAL)
	211	#define CvHASEVAL_on(cv) (CvFLAGS(cv) \|= CVf_HASEVAL)
	212	#define CvHASEVAL_off(cv) (CvFLAGS(cv) &= ~CVf_HASEVAL)
	213
b290562e FC	214	#define CvNAMED(cv) (CvFLAGS(cv) & CVf_NAMED)
	215	#define CvNAMED_on(cv) (CvFLAGS(cv) \|= CVf_NAMED)
	216	#define CvNAMED_off(cv) (CvFLAGS(cv) &= ~CVf_NAMED)
	217
5bb151a5 FC	218	#define CvLEXICAL(cv) (CvFLAGS(cv) & CVf_LEXICAL)
	219	#define CvLEXICAL_on(cv) (CvFLAGS(cv) \|= CVf_LEXICAL)
	220	#define CvLEXICAL_off(cv) (CvFLAGS(cv) &= ~CVf_LEXICAL)
	221
77004dee NC	222	/* Flags for newXS_flags */
	223	#define XS_DYNAMIC_FILENAME 0x01 /* The filename isn't static */
	224
b290562e FC	225	PERL_STATIC_INLINE HEK *
	226	CvNAME_HEK(CV *sv)
	227	{
	228	return CvNAMED(sv)
	229	? ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_gv_u.xcv_hek
	230	: 0;
	231	}
2e800d79 FC	232	/* This lowers the refernce count of the previous value, but does not
	233	increment the reference count of the new value. */
	234	#define CvNAME_HEK_set(cv, hek) ( \
	235	CvNAME_HEK((CV *)(cv)) \
	236	? unshare_hek(SvANY((CV *)(cv))->xcv_gv_u.xcv_hek) \
	237	: (void)0, \
	238	((XPVCV*)MUTABLE_PTR(SvANY(cv)))->xcv_gv_u.xcv_hek = (hek), \
	239	CvNAMED_on(cv) \
	240	)
b290562e	241
7dafbf52 DM	242	/*
	243	=head1 CV reference counts and CvOUTSIDE
	244
	245	=for apidoc m\|bool\|CvWEAKOUTSIDE\|CV *cv
	246
	247	Each CV has a pointer, C<CvOUTSIDE()>, to its lexically enclosing
154e47c8	248	CV (if any). Because pointers to anonymous sub prototypes are
7dafbf52	249	stored in C<&> pad slots, it is a possible to get a circular reference,
154e47c8	250	with the parent pointing to the child and vice-versa. To avoid the
7dafbf52 DM	251	ensuing memory leak, we do not increment the reference count of the CV
7dafbf52 DM	252	pointed to by C<CvOUTSIDE> in the I<one specific instance> that the parent
154e47c8 FC	253	has a C<&> pad slot pointing back to us. In this case, we set the
154e47c8 FC	254	C<CvWEAKOUTSIDE> flag in the child. This allows us to determine under what
7dafbf52 DM	255	circumstances we should decrement the refcount of the parent when freeing
	256	the child.
	257
eeb8d49e	258	There is a further complication with non-closure anonymous subs (i.e. those
154e47c8 FC	259	that do not refer to any lexicals outside that sub). In this case, the
154e47c8 FC	260	anonymous prototype is shared rather than being cloned. This has the
7dafbf52 DM	261	consequence that the parent may be freed while there are still active
	262	children, eg
	263
	264	BEGIN { $a = sub { eval '$x' } }
	265
	266	In this case, the BEGIN is freed immediately after execution since there
	267	are no active references to it: the anon sub prototype has
	268	C<CvWEAKOUTSIDE> set since it's not a closure, and $a points to the same
	269	CV, so it doesn't contribute to BEGIN's refcount either. When $a is
	270	executed, the C<eval '$x'> causes the chain of C<CvOUTSIDE>s to be followed,
	271	and the freed BEGIN is accessed.
	272
	273	To avoid this, whenever a CV and its associated pad is freed, any
	274	C<&> entries in the pad are explicitly removed from the pad, and if the
	275	refcount of the pointed-to anon sub is still positive, then that
154e47c8	276	child's C<CvOUTSIDE> is set to point to its grandparent. This will only
7dafbf52 DM	277	occur in the single specific case of a non-closure anon prototype
	278	having one or more active references (such as C<$a> above).
	279
	280	One other thing to consider is that a CV may be merely undefined
154e47c8	281	rather than freed, eg C<undef &foo>. In this case, its refcount may
7dafbf52 DM	282	not have reached zero, but we still delete its pad and its C<CvROOT> etc.
	283	Since various children may still have their C<CvOUTSIDE> pointing at this
	284	undefined CV, we keep its own C<CvOUTSIDE> for the time being, so that
154e47c8	285	the chain of lexical scopes is unbroken. For example, the following
7dafbf52 DM	286	should print 123:
	287
	288	my $x = 123;
	289	sub tmp { sub { eval '$x' } }
	290	my $a = tmp();
	291	undef &tmp;
	292	print $a->();
	293
	294	=cut
	295	*/
102d3b8a	296
d9088386 Z	297	typedef OP (Perl_call_checker)(pTHX_ OP , GV , SV *);
d9088386 Z	298
aa38f4b1 FC	299	#define CALL_CHECKER_REQUIRE_GV MGf_REQUIRE_GV
aa38f4b1 FC	300
5e881495 FC	301	#define CV_NAME_NOTQUAL 1
5e881495 FC	302
b7acb0a3 FC	303	#ifdef PERL_CORE
	304	# define CV_UNDEF_KEEP_NAME 1
	305	#endif
	306
102d3b8a NC	307	/*
	308	* Local variables:
	309	* c-indentation-style: bsd
	310	* c-basic-offset: 4
14d04a33	311	* indent-tabs-mode: nil
102d3b8a NC	312	* End:
102d3b8a NC	313	*
14d04a33	314	* ex: set ts=8 sts=4 sw=4 et:
102d3b8a	315	*/