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a0d0e21e 1/* cv.h
79072805 2 *
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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
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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 *
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9 */
10
f653aab7 11/* This structure must match the beginning of XPVFM in sv.h */
44a8e56a 12
79072805 13struct xpvcv {
20f4945e 14 _XPV_HEAD;
20f4945e 15 _XPVCV_COMMON;
79072805 16};
748a9306 17
954c1994 18/*
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19=for apidoc Ayh||CV
20
78342678 21=for apidoc ADmnU||Nullcv
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22Null CV pointer.
23
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24(deprecated - use C<(CV *)NULL> instead)
25
954c1994 26=for apidoc Am|HV*|CvSTASH|CV* cv
72d33970 27Returns the stash of the CV. A stash is the symbol table hash, containing
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28the package-scoped variables in the package where the subroutine was defined.
29For more information, see L<perlguts>.
954c1994 30
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31This also has a special use with XS AUTOLOAD subs.
32See L<perlguts/Autoloading with XSUBs>.
33
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34=cut
35*/
36
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37#ifndef PERL_CORE
38# define Nullcv Null(CV*)
39#endif
a5f75d66 40
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41#define CvSTASH(sv) (0+((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_stash)
42#define CvSTASH_set(cv,st) Perl_cvstash_set(aTHX_ cv, st)
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43#define CvSTART(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_start_u.xcv_start
44#define CvROOT(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_root_u.xcv_root
45#define CvXSUB(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_root_u.xcv_xsub
46#define CvXSUBANY(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_start_u.xcv_xsubany
c9182d9c 47#define CvGV(sv) Perl_CvGV(aTHX_ (CV *)(sv))
b3f91e91 48#define CvGV_set(cv,gv) Perl_cvgv_set(aTHX_ cv, gv)
ae77754a 49#define CvHASGV(cv) cBOOL(SvANY(cv)->xcv_gv_u.xcv_gv)
8f629a87 50#define CvFILE(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_file
a636914a 51#ifdef USE_ITHREADS
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52# define CvFILE_set_from_cop(sv, cop) \
53 (CvFILE(sv) = savepv(CopFILE(cop)), CvDYNFILE_on(sv))
a636914a 54#else
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55# define CvFILE_set_from_cop(sv, cop) \
56 (CvFILE(sv) = CopFILE(cop), CvDYNFILE_off(sv))
a636914a 57#endif
9ec2a764 58#define CvFILEGV(sv) (gv_fetchfile(CvFILE(sv)))
74804ad1 59#define CvDEPTH(sv) (*Perl_CvDEPTH((const CV *)sv))
52ec28d5 60/* For use when you only have a XPVCV*, not a real CV*.
74804ad1 61 Must be assert protected as in Perl_CvDEPTH before use. */
52ec28d5 62#define CvDEPTHunsafe(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_depth
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63
64/* these CvPADLIST/CvRESERVED asserts can be reverted one day, once stabilized */
65#define CvPADLIST(sv) (*(assert_(!CvISXSUB((CV*)(sv))) \
66 &(((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist)))
67/* CvPADLIST_set is not public API, it can be removed one day, once stabilized */
68#ifdef DEBUGGING
e69651e7 69# define CvPADLIST_set(sv, padlist) Perl_set_padlist((CV*)sv, padlist)
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70#else
71# define CvPADLIST_set(sv, padlist) (CvPADLIST(sv) = (padlist))
72#endif
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73#define CvHSCXT(sv) *(assert_(CvISXSUB((CV*)(sv))) \
74 &(((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_hscxt))
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75#ifdef DEBUGGING
76# if PTRSIZE == 8
77# define PoisonPADLIST(sv) \
78 (((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist = (PADLIST *)UINT64_C(0xEFEFEFEFEFEFEFEF))
79# elif PTRSIZE == 4
80# define PoisonPADLIST(sv) \
81 (((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_padlist = (PADLIST *)0xEFEFEFEF)
82# else
83# error unknown pointer size
84# endif
85#else
eba7d13f 86# define PoisonPADLIST(sv) NOOP
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87#endif
88
52ec28d5 89#define CvOUTSIDE(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside
8f629a87 90#define CvOUTSIDE_SEQ(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside_seq
52ec28d5 91#define CvFLAGS(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_flags
a5f75d66 92
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93/* These two are sometimes called on non-CVs */
94#define CvPROTO(sv) \
95 ( \
96 SvPOK(sv) \
97 ? SvTYPE(sv) == SVt_PVCV && CvAUTOLOAD(sv) \
98 ? SvEND(sv)+1 : SvPVX_const(sv) \
99 : NULL \
100 )
101#define CvPROTOLEN(sv) \
102 ( \
103 SvPOK(sv) \
104 ? SvTYPE(sv) == SVt_PVCV && CvAUTOLOAD(sv) \
105 ? SvLEN(sv)-SvCUR(sv)-2 \
106 : SvCUR(sv) \
107 : 0 \
108 )
109
5b4563c8 110#define CVf_METHOD 0x0001 /* CV is explicitly marked as a method */
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111#define CVf_LVALUE 0x0002 /* CV return value can be used as lvalue */
112#define CVf_CONST 0x0004 /* inlinable sub */
113#define CVf_ISXSUB 0x0008 /* CV is an XSUB, not pure perl. */
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114
115#define CVf_WEAKOUTSIDE 0x0010 /* CvOUTSIDE isn't ref counted */
116#define CVf_CLONE 0x0020 /* anon CV uses external lexicals */
117#define CVf_CLONED 0x0040 /* a clone of one of those */
cfc1e951 118#define CVf_ANON 0x0080 /* CV is not pointed to by a GV */
5b4563c8 119#define CVf_UNIQUE 0x0100 /* sub is only called once (eg PL_main_cv,
1108974d 120 * require, eval). */
5b4563c8 121#define CVf_NODEBUG 0x0200 /* no DB::sub indirection for this CV
8ebc5c01 122 (esp. useful for special XSUBs) */
cfc1e951 123#define CVf_CVGV_RC 0x0400 /* CvGV is reference counted */
c6565d4b 124#if defined(PERL_CORE) || defined(PERL_EXT)
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125# define CVf_SLABBED 0x0800 /* Holds refcount on op slab */
126#endif
f60d17f5 127#define CVf_DYNFILE 0x1000 /* The filename is malloced */
8fa6a409 128#define CVf_AUTOLOAD 0x2000 /* SvPVX contains AUTOLOADed sub name */
a0d2bbd5 129#define CVf_HASEVAL 0x4000 /* contains string eval */
b290562e 130#define CVf_NAMED 0x8000 /* Has a name HEK */
5bb151a5 131#define CVf_LEXICAL 0x10000 /* Omit package from name */
956dfca8 132#define CVf_ANONCONST 0x20000 /* :const - create anonconst op */
7dafbf52 133
d3cea301 134/* This symbol for optimised communication between toke.c and op.c: */
956dfca8 135#define CVf_BUILTIN_ATTRS (CVf_METHOD|CVf_LVALUE|CVf_ANONCONST)
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136
137#define CvCLONE(cv) (CvFLAGS(cv) & CVf_CLONE)
138#define CvCLONE_on(cv) (CvFLAGS(cv) |= CVf_CLONE)
139#define CvCLONE_off(cv) (CvFLAGS(cv) &= ~CVf_CLONE)
140
141#define CvCLONED(cv) (CvFLAGS(cv) & CVf_CLONED)
142#define CvCLONED_on(cv) (CvFLAGS(cv) |= CVf_CLONED)
143#define CvCLONED_off(cv) (CvFLAGS(cv) &= ~CVf_CLONED)
144
145#define CvANON(cv) (CvFLAGS(cv) & CVf_ANON)
146#define CvANON_on(cv) (CvFLAGS(cv) |= CVf_ANON)
147#define CvANON_off(cv) (CvFLAGS(cv) &= ~CVf_ANON)
79072805 148
a2278b6a 149/* CvEVAL or CvSPECIAL */
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150#define CvUNIQUE(cv) (CvFLAGS(cv) & CVf_UNIQUE)
151#define CvUNIQUE_on(cv) (CvFLAGS(cv) |= CVf_UNIQUE)
152#define CvUNIQUE_off(cv) (CvFLAGS(cv) &= ~CVf_UNIQUE)
8ebc5c01 153
154#define CvNODEBUG(cv) (CvFLAGS(cv) & CVf_NODEBUG)
155#define CvNODEBUG_on(cv) (CvFLAGS(cv) |= CVf_NODEBUG)
156#define CvNODEBUG_off(cv) (CvFLAGS(cv) &= ~CVf_NODEBUG)
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157
158#define CvMETHOD(cv) (CvFLAGS(cv) & CVf_METHOD)
159#define CvMETHOD_on(cv) (CvFLAGS(cv) |= CVf_METHOD)
160#define CvMETHOD_off(cv) (CvFLAGS(cv) &= ~CVf_METHOD)
161
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162#define CvLVALUE(cv) (CvFLAGS(cv) & CVf_LVALUE)
163#define CvLVALUE_on(cv) (CvFLAGS(cv) |= CVf_LVALUE)
164#define CvLVALUE_off(cv) (CvFLAGS(cv) &= ~CVf_LVALUE)
165
a2278b6a 166/* eval or PL_main_cv */
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167#define CvEVAL(cv) (CvUNIQUE(cv) && !SvFAKE(cv))
168#define CvEVAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_off(cv))
169#define CvEVAL_off(cv) CvUNIQUE_off(cv)
170
3c10abe3 171/* BEGIN|CHECK|INIT|UNITCHECK|END */
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172#define CvSPECIAL(cv) (CvUNIQUE(cv) && SvFAKE(cv))
173#define CvSPECIAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_on(cv))
174#define CvSPECIAL_off(cv) (CvUNIQUE_off(cv),SvFAKE_off(cv))
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175
176#define CvCONST(cv) (CvFLAGS(cv) & CVf_CONST)
177#define CvCONST_on(cv) (CvFLAGS(cv) |= CVf_CONST)
178#define CvCONST_off(cv) (CvFLAGS(cv) &= ~CVf_CONST)
a4f1a029 179
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180#define CvWEAKOUTSIDE(cv) (CvFLAGS(cv) & CVf_WEAKOUTSIDE)
181#define CvWEAKOUTSIDE_on(cv) (CvFLAGS(cv) |= CVf_WEAKOUTSIDE)
182#define CvWEAKOUTSIDE_off(cv) (CvFLAGS(cv) &= ~CVf_WEAKOUTSIDE)
183
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184#define CvISXSUB(cv) (CvFLAGS(cv) & CVf_ISXSUB)
185#define CvISXSUB_on(cv) (CvFLAGS(cv) |= CVf_ISXSUB)
186#define CvISXSUB_off(cv) (CvFLAGS(cv) &= ~CVf_ISXSUB)
187
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188#define CvCVGV_RC(cv) (CvFLAGS(cv) & CVf_CVGV_RC)
189#define CvCVGV_RC_on(cv) (CvFLAGS(cv) |= CVf_CVGV_RC)
190#define CvCVGV_RC_off(cv) (CvFLAGS(cv) &= ~CVf_CVGV_RC)
191
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192#ifdef PERL_CORE
193# define CvSLABBED(cv) (CvFLAGS(cv) & CVf_SLABBED)
194# define CvSLABBED_on(cv) (CvFLAGS(cv) |= CVf_SLABBED)
195# define CvSLABBED_off(cv) (CvFLAGS(cv) &= ~CVf_SLABBED)
196#endif
197
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198#define CvDYNFILE(cv) (CvFLAGS(cv) & CVf_DYNFILE)
199#define CvDYNFILE_on(cv) (CvFLAGS(cv) |= CVf_DYNFILE)
200#define CvDYNFILE_off(cv) (CvFLAGS(cv) &= ~CVf_DYNFILE)
201
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202#define CvAUTOLOAD(cv) (CvFLAGS(cv) & CVf_AUTOLOAD)
203#define CvAUTOLOAD_on(cv) (CvFLAGS(cv) |= CVf_AUTOLOAD)
204#define CvAUTOLOAD_off(cv) (CvFLAGS(cv) &= ~CVf_AUTOLOAD)
205
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206#define CvHASEVAL(cv) (CvFLAGS(cv) & CVf_HASEVAL)
207#define CvHASEVAL_on(cv) (CvFLAGS(cv) |= CVf_HASEVAL)
208#define CvHASEVAL_off(cv) (CvFLAGS(cv) &= ~CVf_HASEVAL)
209
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210#define CvNAMED(cv) (CvFLAGS(cv) & CVf_NAMED)
211#define CvNAMED_on(cv) (CvFLAGS(cv) |= CVf_NAMED)
212#define CvNAMED_off(cv) (CvFLAGS(cv) &= ~CVf_NAMED)
213
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214#define CvLEXICAL(cv) (CvFLAGS(cv) & CVf_LEXICAL)
215#define CvLEXICAL_on(cv) (CvFLAGS(cv) |= CVf_LEXICAL)
216#define CvLEXICAL_off(cv) (CvFLAGS(cv) &= ~CVf_LEXICAL)
217
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218#define CvANONCONST(cv) (CvFLAGS(cv) & CVf_ANONCONST)
219#define CvANONCONST_on(cv) (CvFLAGS(cv) |= CVf_ANONCONST)
220#define CvANONCONST_off(cv) (CvFLAGS(cv) &= ~CVf_ANONCONST)
221
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222/* Flags for newXS_flags */
223#define XS_DYNAMIC_FILENAME 0x01 /* The filename isn't static */
224
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225PERL_STATIC_INLINE HEK *
226CvNAME_HEK(CV *sv)
227{
228 return CvNAMED(sv)
229 ? ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_gv_u.xcv_hek
230 : 0;
231}
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232
233/* helper for the common pattern:
234 CvNAMED(sv) ? CvNAME_HEK((CV *)sv) : GvNAME_HEK(CvGV(sv))
235*/
236#define CvGvNAME_HEK(sv) ( \
237 CvNAMED((CV*)sv) ? \
238 ((XPVCV*)MUTABLE_PTR(SvANY((SV*)sv)))->xcv_gv_u.xcv_hek\
239 : GvNAME_HEK(CvGV( (SV*) sv)) \
240 )
241
242/* This lowers the reference count of the previous value, but does *not*
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243 increment the reference count of the new value. */
244#define CvNAME_HEK_set(cv, hek) ( \
245 CvNAME_HEK((CV *)(cv)) \
246 ? unshare_hek(SvANY((CV *)(cv))->xcv_gv_u.xcv_hek) \
247 : (void)0, \
248 ((XPVCV*)MUTABLE_PTR(SvANY(cv)))->xcv_gv_u.xcv_hek = (hek), \
249 CvNAMED_on(cv) \
250 )
b290562e 251
7dafbf52 252/*
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253
254=for apidoc m|bool|CvWEAKOUTSIDE|CV *cv
255
256Each CV has a pointer, C<CvOUTSIDE()>, to its lexically enclosing
154e47c8 257CV (if any). Because pointers to anonymous sub prototypes are
7dafbf52 258stored in C<&> pad slots, it is a possible to get a circular reference,
154e47c8 259with the parent pointing to the child and vice-versa. To avoid the
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260ensuing memory leak, we do not increment the reference count of the CV
261pointed to by C<CvOUTSIDE> in the I<one specific instance> that the parent
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262has a C<&> pad slot pointing back to us. In this case, we set the
263C<CvWEAKOUTSIDE> flag in the child. This allows us to determine under what
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264circumstances we should decrement the refcount of the parent when freeing
265the child.
266
eeb8d49e 267There is a further complication with non-closure anonymous subs (i.e. those
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268that do not refer to any lexicals outside that sub). In this case, the
269anonymous prototype is shared rather than being cloned. This has the
7dafbf52 270consequence that the parent may be freed while there are still active
dfcfced8 271children, I<e.g.>,
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272
273 BEGIN { $a = sub { eval '$x' } }
274
275In this case, the BEGIN is freed immediately after execution since there
276are no active references to it: the anon sub prototype has
277C<CvWEAKOUTSIDE> set since it's not a closure, and $a points to the same
278CV, so it doesn't contribute to BEGIN's refcount either. When $a is
279executed, the C<eval '$x'> causes the chain of C<CvOUTSIDE>s to be followed,
280and the freed BEGIN is accessed.
281
282To avoid this, whenever a CV and its associated pad is freed, any
283C<&> entries in the pad are explicitly removed from the pad, and if the
284refcount of the pointed-to anon sub is still positive, then that
154e47c8 285child's C<CvOUTSIDE> is set to point to its grandparent. This will only
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286occur in the single specific case of a non-closure anon prototype
287having one or more active references (such as C<$a> above).
288
289One other thing to consider is that a CV may be merely undefined
154e47c8 290rather than freed, eg C<undef &foo>. In this case, its refcount may
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291not have reached zero, but we still delete its pad and its C<CvROOT> etc.
292Since various children may still have their C<CvOUTSIDE> pointing at this
293undefined CV, we keep its own C<CvOUTSIDE> for the time being, so that
154e47c8 294the chain of lexical scopes is unbroken. For example, the following
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295should print 123:
296
297 my $x = 123;
298 sub tmp { sub { eval '$x' } }
299 my $a = tmp();
300 undef &tmp;
301 print $a->();
302
303=cut
304*/
102d3b8a 305
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306typedef OP *(*Perl_call_checker)(pTHX_ OP *, GV *, SV *);
307
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308#define CALL_CHECKER_REQUIRE_GV MGf_REQUIRE_GV
309
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310#define CV_NAME_NOTQUAL 1
311
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312#ifdef PERL_CORE
313# define CV_UNDEF_KEEP_NAME 1
314#endif
315
102d3b8a 316/*
14d04a33 317 * ex: set ts=8 sts=4 sw=4 et:
102d3b8a 318 */