File Coverage

ext/mro/../../cv.h
Criterion Covered Total %
statement 2 3 66.7
branch n/a
condition n/a
subroutine n/a
total 2 3 66.7


line stmt bran cond sub time code
1           /* cv.h
2           *
3           * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001,
4           * 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
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           *
9           */
10            
11           /* This structure must match the beginning of XPVFM in sv.h */
12            
13           struct xpvcv {
14           _XPV_HEAD;
15           _XPVCV_COMMON;
16           };
17            
18           /*
19           =head1 Handy Values
20            
21           =for apidoc AmU||Nullcv
22           Null CV pointer.
23            
24           (deprecated - use C<(CV *)NULL> instead)
25            
26           =head1 CV Manipulation Functions
27            
28           This section documents functions to manipulate CVs which are code-values,
29           or subroutines. For more information, see L.
30            
31           =for apidoc Am|HV*|CvSTASH|CV* cv
32           Returns the stash of the CV. A stash is the symbol table hash, containing
33           the package-scoped variables in the package where the subroutine was defined.
34           For more information, see L.
35            
36           This also has a special use with XS AUTOLOAD subs.
37           See L.
38            
39           =cut
40           */
41            
42           #ifndef PERL_CORE
43           # define Nullcv Null(CV*)
44           #endif
45            
46           #define CvSTASH(sv) (0+((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_stash)
47           #define CvSTASH_set(cv,st) Perl_cvstash_set(aTHX_ cv, st)
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
52           #define CvGV(sv) S_CvGV((const CV *)(sv))
53           #define CvGV_set(cv,gv) Perl_cvgv_set(aTHX_ cv, gv)
54           #define CvFILE(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_file
55           #ifdef USE_ITHREADS
56           # define CvFILE_set_from_cop(sv, cop) \
57           (CvFILE(sv) = savepv(CopFILE(cop)), CvDYNFILE_on(sv))
58           #else
59           # define CvFILE_set_from_cop(sv, cop) \
60           (CvFILE(sv) = CopFILE(cop), CvDYNFILE_off(sv))
61           #endif
62           #define CvFILEGV(sv) (gv_fetchfile(CvFILE(sv)))
63           #define CvDEPTH(sv) (*S_CvDEPTHp((const CV *)sv))
64           #define CvPADLIST(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist
65           #define CvOUTSIDE(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside
66           #define CvFLAGS(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_flags
67           #define CvOUTSIDE_SEQ(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside_seq
68            
69           /* These two are sometimes called on non-CVs */
70           #define CvPROTO(sv) \
71           ( \
72           SvPOK(sv) \
73           ? SvTYPE(sv) == SVt_PVCV && CvAUTOLOAD(sv) \
74           ? SvEND(sv)+1 : SvPVX_const(sv) \
75           : NULL \
76           )
77           #define CvPROTOLEN(sv) \
78           ( \
79           SvPOK(sv) \
80           ? SvTYPE(sv) == SVt_PVCV && CvAUTOLOAD(sv) \
81           ? SvLEN(sv)-SvCUR(sv)-2 \
82           : SvCUR(sv) \
83           : 0 \
84           )
85            
86           #define CVf_METHOD 0x0001 /* CV is explicitly marked as a method */
87           #define CVf_LVALUE 0x0002 /* CV return value can be used as lvalue */
88           #define CVf_CONST 0x0004 /* inlinable sub */
89           #define CVf_ISXSUB 0x0008 /* CV is an XSUB, not pure perl. */
90            
91           #define CVf_WEAKOUTSIDE 0x0010 /* CvOUTSIDE isn't ref counted */
92           #define CVf_CLONE 0x0020 /* anon CV uses external lexicals */
93           #define CVf_CLONED 0x0040 /* a clone of one of those */
94           #define CVf_ANON 0x0080 /* CV is not pointed to by a GV */
95           #define CVf_UNIQUE 0x0100 /* sub is only called once (eg PL_main_cv,
96           * require, eval). */
97           #define CVf_NODEBUG 0x0200 /* no DB::sub indirection for this CV
98           (esp. useful for special XSUBs) */
99           #define CVf_CVGV_RC 0x0400 /* CvGV is reference counted */
100           #ifdef PERL_CORE
101           # define CVf_SLABBED 0x0800 /* Holds refcount on op slab */
102           #endif
103           #define CVf_DYNFILE 0x1000 /* The filename isn't static */
104           #define CVf_AUTOLOAD 0x2000 /* SvPVX contains AUTOLOADed sub name */
105           #define CVf_HASEVAL 0x4000 /* contains string eval */
106           #define CVf_NAMED 0x8000 /* Has a name HEK */
107            
108           /* This symbol for optimised communication between toke.c and op.c: */
109           #define CVf_BUILTIN_ATTRS (CVf_METHOD|CVf_LVALUE)
110            
111           #define CvCLONE(cv) (CvFLAGS(cv) & CVf_CLONE)
112           #define CvCLONE_on(cv) (CvFLAGS(cv) |= CVf_CLONE)
113           #define CvCLONE_off(cv) (CvFLAGS(cv) &= ~CVf_CLONE)
114            
115           #define CvCLONED(cv) (CvFLAGS(cv) & CVf_CLONED)
116           #define CvCLONED_on(cv) (CvFLAGS(cv) |= CVf_CLONED)
117           #define CvCLONED_off(cv) (CvFLAGS(cv) &= ~CVf_CLONED)
118            
119           #define CvANON(cv) (CvFLAGS(cv) & CVf_ANON)
120           #define CvANON_on(cv) (CvFLAGS(cv) |= CVf_ANON)
121           #define CvANON_off(cv) (CvFLAGS(cv) &= ~CVf_ANON)
122            
123           /* CvEVAL or CvSPECIAL */
124           #define CvUNIQUE(cv) (CvFLAGS(cv) & CVf_UNIQUE)
125           #define CvUNIQUE_on(cv) (CvFLAGS(cv) |= CVf_UNIQUE)
126           #define CvUNIQUE_off(cv) (CvFLAGS(cv) &= ~CVf_UNIQUE)
127            
128           #define CvNODEBUG(cv) (CvFLAGS(cv) & CVf_NODEBUG)
129           #define CvNODEBUG_on(cv) (CvFLAGS(cv) |= CVf_NODEBUG)
130           #define CvNODEBUG_off(cv) (CvFLAGS(cv) &= ~CVf_NODEBUG)
131            
132           #define CvMETHOD(cv) (CvFLAGS(cv) & CVf_METHOD)
133           #define CvMETHOD_on(cv) (CvFLAGS(cv) |= CVf_METHOD)
134           #define CvMETHOD_off(cv) (CvFLAGS(cv) &= ~CVf_METHOD)
135            
136           #define CvLVALUE(cv) (CvFLAGS(cv) & CVf_LVALUE)
137           #define CvLVALUE_on(cv) (CvFLAGS(cv) |= CVf_LVALUE)
138           #define CvLVALUE_off(cv) (CvFLAGS(cv) &= ~CVf_LVALUE)
139            
140           /* eval or PL_main_cv */
141           #define CvEVAL(cv) (CvUNIQUE(cv) && !SvFAKE(cv))
142           #define CvEVAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_off(cv))
143           #define CvEVAL_off(cv) CvUNIQUE_off(cv)
144            
145           /* BEGIN|CHECK|INIT|UNITCHECK|END */
146           #define CvSPECIAL(cv) (CvUNIQUE(cv) && SvFAKE(cv))
147           #define CvSPECIAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_on(cv))
148           #define CvSPECIAL_off(cv) (CvUNIQUE_off(cv),SvFAKE_off(cv))
149            
150           #define CvCONST(cv) (CvFLAGS(cv) & CVf_CONST)
151           #define CvCONST_on(cv) (CvFLAGS(cv) |= CVf_CONST)
152           #define CvCONST_off(cv) (CvFLAGS(cv) &= ~CVf_CONST)
153            
154           #define CvWEAKOUTSIDE(cv) (CvFLAGS(cv) & CVf_WEAKOUTSIDE)
155           #define CvWEAKOUTSIDE_on(cv) (CvFLAGS(cv) |= CVf_WEAKOUTSIDE)
156           #define CvWEAKOUTSIDE_off(cv) (CvFLAGS(cv) &= ~CVf_WEAKOUTSIDE)
157            
158           #define CvISXSUB(cv) (CvFLAGS(cv) & CVf_ISXSUB)
159           #define CvISXSUB_on(cv) (CvFLAGS(cv) |= CVf_ISXSUB)
160           #define CvISXSUB_off(cv) (CvFLAGS(cv) &= ~CVf_ISXSUB)
161            
162           #define CvCVGV_RC(cv) (CvFLAGS(cv) & CVf_CVGV_RC)
163           #define CvCVGV_RC_on(cv) (CvFLAGS(cv) |= CVf_CVGV_RC)
164           #define CvCVGV_RC_off(cv) (CvFLAGS(cv) &= ~CVf_CVGV_RC)
165            
166           #ifdef PERL_CORE
167           # define CvSLABBED(cv) (CvFLAGS(cv) & CVf_SLABBED)
168           # define CvSLABBED_on(cv) (CvFLAGS(cv) |= CVf_SLABBED)
169           # define CvSLABBED_off(cv) (CvFLAGS(cv) &= ~CVf_SLABBED)
170           #endif
171            
172           #define CvDYNFILE(cv) (CvFLAGS(cv) & CVf_DYNFILE)
173           #define CvDYNFILE_on(cv) (CvFLAGS(cv) |= CVf_DYNFILE)
174           #define CvDYNFILE_off(cv) (CvFLAGS(cv) &= ~CVf_DYNFILE)
175            
176           #define CvAUTOLOAD(cv) (CvFLAGS(cv) & CVf_AUTOLOAD)
177           #define CvAUTOLOAD_on(cv) (CvFLAGS(cv) |= CVf_AUTOLOAD)
178           #define CvAUTOLOAD_off(cv) (CvFLAGS(cv) &= ~CVf_AUTOLOAD)
179            
180           #define CvHASEVAL(cv) (CvFLAGS(cv) & CVf_HASEVAL)
181           #define CvHASEVAL_on(cv) (CvFLAGS(cv) |= CVf_HASEVAL)
182           #define CvHASEVAL_off(cv) (CvFLAGS(cv) &= ~CVf_HASEVAL)
183            
184           #define CvNAMED(cv) (CvFLAGS(cv) & CVf_NAMED)
185           #define CvNAMED_on(cv) (CvFLAGS(cv) |= CVf_NAMED)
186           #define CvNAMED_off(cv) (CvFLAGS(cv) &= ~CVf_NAMED)
187            
188           /* Flags for newXS_flags */
189           #define XS_DYNAMIC_FILENAME 0x01 /* The filename isn't static */
190            
191           PERL_STATIC_INLINE GV *
192 0         S_CvGV(const CV *sv)
193           {
194 3272536         return CvNAMED(sv)
195           ? 0
196 3272536         : ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_gv_u.xcv_gv;
197           }
198           PERL_STATIC_INLINE HEK *
199           CvNAME_HEK(CV *sv)
200           {
201           return CvNAMED(sv)
202           ? ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_gv_u.xcv_hek
203           : 0;
204           }
205           /* This lowers the refernce count of the previous value, but does *not*
206           increment the reference count of the new value. */
207           #define CvNAME_HEK_set(cv, hek) ( \
208           CvNAME_HEK((CV *)(cv)) \
209           ? unshare_hek(SvANY((CV *)(cv))->xcv_gv_u.xcv_hek) \
210           : (void)0, \
211           ((XPVCV*)MUTABLE_PTR(SvANY(cv)))->xcv_gv_u.xcv_hek = (hek), \
212           CvNAMED_on(cv) \
213           )
214            
215           /*
216           =head1 CV reference counts and CvOUTSIDE
217            
218           =for apidoc m|bool|CvWEAKOUTSIDE|CV *cv
219            
220           Each CV has a pointer, C, to its lexically enclosing
221           CV (if any). Because pointers to anonymous sub prototypes are
222           stored in C<&> pad slots, it is a possible to get a circular reference,
223           with the parent pointing to the child and vice-versa. To avoid the
224           ensuing memory leak, we do not increment the reference count of the CV
225           pointed to by C in the I that the parent
226           has a C<&> pad slot pointing back to us. In this case, we set the
227           C flag in the child. This allows us to determine under what
228           circumstances we should decrement the refcount of the parent when freeing
229           the child.
230            
231           There is a further complication with non-closure anonymous subs (i.e. those
232           that do not refer to any lexicals outside that sub). In this case, the
233           anonymous prototype is shared rather than being cloned. This has the
234           consequence that the parent may be freed while there are still active
235           children, eg
236            
237           BEGIN { $a = sub { eval '$x' } }
238            
239           In this case, the BEGIN is freed immediately after execution since there
240           are no active references to it: the anon sub prototype has
241           C set since it's not a closure, and $a points to the same
242           CV, so it doesn't contribute to BEGIN's refcount either. When $a is
243           executed, the C causes the chain of Cs to be followed,
244           and the freed BEGIN is accessed.
245            
246           To avoid this, whenever a CV and its associated pad is freed, any
247           C<&> entries in the pad are explicitly removed from the pad, and if the
248           refcount of the pointed-to anon sub is still positive, then that
249           child's C is set to point to its grandparent. This will only
250           occur in the single specific case of a non-closure anon prototype
251           having one or more active references (such as C<$a> above).
252            
253           One other thing to consider is that a CV may be merely undefined
254           rather than freed, eg C. In this case, its refcount may
255           not have reached zero, but we still delete its pad and its C etc.
256           Since various children may still have their C pointing at this
257           undefined CV, we keep its own C for the time being, so that
258           the chain of lexical scopes is unbroken. For example, the following
259           should print 123:
260            
261           my $x = 123;
262           sub tmp { sub { eval '$x' } }
263           my $a = tmp();
264           undef &tmp;
265           print $a->();
266            
267           =cut
268           */
269            
270           typedef OP *(*Perl_call_checker)(pTHX_ OP *, GV *, SV *);
271            
272           /*
273           * Local variables:
274           * c-indentation-style: bsd
275           * c-basic-offset: 4
276           * indent-tabs-mode: nil
277           * End:
278           *
279           * ex: set ts=8 sts=4 sw=4 et:
280           */