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 =for apidoc Ayh||CV 20 21 =for apidoc ADmnU||Nullcv 22 Null CV pointer. 23 24 (deprecated - use C<(CV *)NULL> instead) 25 26 =for apidoc Am|HV*|CvSTASH|CV* cv 27 Returns the stash of the CV. A stash is the symbol table hash, containing 28 the package-scoped variables in the package where the subroutine was defined. 29 For more information, see L<perlguts>. 30 31 This also has a special use with XS AUTOLOAD subs. 32 See L<perlguts/Autoloading with XSUBs>. 33 34 =cut 35 */ 36 37 #ifndef PERL_CORE 38 # define Nullcv Null(CV*) 39 #endif 40 41 #define CvSTASH(sv) (MUTABLE_HV(((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_stash)) 42 #define CvSTASH_set(cv,st) Perl_cvstash_set(aTHX_ cv, st) 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 47 #define CvGV(sv) Perl_CvGV(aTHX_ (CV *)(sv)) 48 #define CvGV_set(cv,gv) Perl_cvgv_set(aTHX_ cv, gv) 49 #define CvHASGV(cv) cBOOL(SvANY(cv)->xcv_gv_u.xcv_gv) 50 #define CvFILE(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_file 51 #ifdef USE_ITHREADS 52 # define CvFILE_set_from_cop(sv, cop) \ 53 (CvFILE(sv) = savepv(CopFILE(cop)), CvDYNFILE_on(sv)) 54 #else 55 # define CvFILE_set_from_cop(sv, cop) \ 56 (CvFILE(sv) = CopFILE(cop), CvDYNFILE_off(sv)) 57 #endif 58 #define CvFILEGV(sv) (gv_fetchfile(CvFILE(sv))) 59 #define CvDEPTH(sv) (*Perl_CvDEPTH((const CV *)sv)) 60 /* For use when you only have a XPVCV*, not a real CV*. 61 Must be assert protected as in Perl_CvDEPTH before use. */ 62 #define CvDEPTHunsafe(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_depth 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 69 # define CvPADLIST_set(sv, padlist) Perl_set_padlist((CV*)sv, padlist) 70 #else 71 # define CvPADLIST_set(sv, padlist) (CvPADLIST(sv) = (padlist)) 72 #endif 73 #define CvHSCXT(sv) *(assert_(CvISXSUB((CV*)(sv))) \ 74 &(((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist_u.xcv_hscxt)) 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 86 # define PoisonPADLIST(sv) NOOP 87 #endif 88 89 #define CvOUTSIDE(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside 90 #define CvOUTSIDE_SEQ(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside_seq 91 #define CvFLAGS(sv) ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_flags 92 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 ) 109 110 /* CV has the `:method` attribute. This used to be called CVf_METHOD but is 111 * renamed to avoid collision with CVf_IsMETHOD */ 112 #define CVf_NOWARN_AMBIGUOUS 0x0001 113 114 #define CVf_LVALUE 0x0002 /* CV return value can be used as lvalue */ 115 #define CVf_CONST 0x0004 /* inlinable sub */ 116 #define CVf_ISXSUB 0x0008 /* CV is an XSUB, not pure perl. */ 117 118 #define CVf_WEAKOUTSIDE 0x0010 /* CvOUTSIDE isn't ref counted */ 119 #define CVf_CLONE 0x0020 /* anon CV uses external lexicals */ 120 #define CVf_CLONED 0x0040 /* a clone of one of those */ 121 #define CVf_ANON 0x0080 /* CV is not pointed to by a GV */ 122 #define CVf_UNIQUE 0x0100 /* sub is only called once (eg PL_main_cv, 123 require, eval). */ 124 #define CVf_NODEBUG 0x0200 /* no DB::sub indirection for this CV 125 (esp. useful for special XSUBs) */ 126 #define CVf_CVGV_RC 0x0400 /* CvGV is reference counted */ 127 #if defined(PERL_CORE) || defined(PERL_EXT) 128 # define CVf_SLABBED 0x0800 /* Holds refcount on op slab */ 129 #endif 130 #define CVf_DYNFILE 0x1000 /* The filename is malloced */ 131 #define CVf_AUTOLOAD 0x2000 /* SvPVX contains AUTOLOADed sub name */ 132 #define CVf_HASEVAL 0x4000 /* contains string eval */ 133 #define CVf_NAMED 0x8000 /* Has a name HEK */ 134 #define CVf_LEXICAL 0x10000 /* Omit package from name */ 135 #define CVf_ANONCONST 0x20000 /* :const - create anonconst op */ 136 #define CVf_SIGNATURE 0x40000 /* CV uses a signature */ 137 #define CVf_REFCOUNTED_ANYSV 0x80000 /* CvXSUBANY().any_sv is refcounted */ 138 #define CVf_IsMETHOD 0x100000 /* CV is a (real) method of a real class. Not 139 to be confused with what used to be called 140 CVf_METHOD; now CVf_NOWARN_AMBIGUOUS */ 141 142 /* This symbol for optimised communication between toke.c and op.c: */ 143 #define CVf_BUILTIN_ATTRS (CVf_NOWARN_AMBIGUOUS|CVf_LVALUE|CVf_ANONCONST) 144 145 #define CvCLONE(cv) (CvFLAGS(cv) & CVf_CLONE) 146 #define CvCLONE_on(cv) (CvFLAGS(cv) |= CVf_CLONE) 147 #define CvCLONE_off(cv) (CvFLAGS(cv) &= ~CVf_CLONE) 148 149 #define CvCLONED(cv) (CvFLAGS(cv) & CVf_CLONED) 150 #define CvCLONED_on(cv) (CvFLAGS(cv) |= CVf_CLONED) 151 #define CvCLONED_off(cv) (CvFLAGS(cv) &= ~CVf_CLONED) 152 153 #define CvANON(cv) (CvFLAGS(cv) & CVf_ANON) 154 #define CvANON_on(cv) (CvFLAGS(cv) |= CVf_ANON) 155 #define CvANON_off(cv) (CvFLAGS(cv) &= ~CVf_ANON) 156 157 /* CvEVAL or CvSPECIAL */ 158 #define CvUNIQUE(cv) (CvFLAGS(cv) & CVf_UNIQUE) 159 #define CvUNIQUE_on(cv) (CvFLAGS(cv) |= CVf_UNIQUE) 160 #define CvUNIQUE_off(cv) (CvFLAGS(cv) &= ~CVf_UNIQUE) 161 162 #define CvNODEBUG(cv) (CvFLAGS(cv) & CVf_NODEBUG) 163 #define CvNODEBUG_on(cv) (CvFLAGS(cv) |= CVf_NODEBUG) 164 #define CvNODEBUG_off(cv) (CvFLAGS(cv) &= ~CVf_NODEBUG) 165 166 #define CvNOWARN_AMBIGUOUS(cv) (CvFLAGS(cv) & CVf_NOWARN_AMBIGUOUS) 167 #define CvNOWARN_AMBIGUOUS_on(cv) (CvFLAGS(cv) |= CVf_NOWARN_AMBIGUOUS) 168 #define CvNOWARN_AMBIGUOUS_off(cv) (CvFLAGS(cv) &= ~CVf_NOWARN_AMBIGUOUS) 169 170 #define CvLVALUE(cv) (CvFLAGS(cv) & CVf_LVALUE) 171 #define CvLVALUE_on(cv) (CvFLAGS(cv) |= CVf_LVALUE) 172 #define CvLVALUE_off(cv) (CvFLAGS(cv) &= ~CVf_LVALUE) 173 174 /* eval or PL_main_cv */ 175 #define CvEVAL(cv) (CvUNIQUE(cv) && !SvFAKE(cv)) 176 #define CvEVAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_off(cv)) 177 #define CvEVAL_off(cv) CvUNIQUE_off(cv) 178 179 /* BEGIN|CHECK|INIT|UNITCHECK|END */ 180 #define CvSPECIAL(cv) (CvUNIQUE(cv) && SvFAKE(cv)) 181 #define CvSPECIAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_on(cv)) 182 #define CvSPECIAL_off(cv) (CvUNIQUE_off(cv),SvFAKE_off(cv)) 183 184 #define CvCONST(cv) (CvFLAGS(cv) & CVf_CONST) 185 #define CvCONST_on(cv) (CvFLAGS(cv) |= CVf_CONST) 186 #define CvCONST_off(cv) (CvFLAGS(cv) &= ~CVf_CONST) 187 188 #define CvWEAKOUTSIDE(cv) (CvFLAGS(cv) & CVf_WEAKOUTSIDE) 189 #define CvWEAKOUTSIDE_on(cv) (CvFLAGS(cv) |= CVf_WEAKOUTSIDE) 190 #define CvWEAKOUTSIDE_off(cv) (CvFLAGS(cv) &= ~CVf_WEAKOUTSIDE) 191 192 #define CvISXSUB(cv) (CvFLAGS(cv) & CVf_ISXSUB) 193 #define CvISXSUB_on(cv) (CvFLAGS(cv) |= CVf_ISXSUB) 194 #define CvISXSUB_off(cv) (CvFLAGS(cv) &= ~CVf_ISXSUB) 195 196 #define CvCVGV_RC(cv) (CvFLAGS(cv) & CVf_CVGV_RC) 197 #define CvCVGV_RC_on(cv) (CvFLAGS(cv) |= CVf_CVGV_RC) 198 #define CvCVGV_RC_off(cv) (CvFLAGS(cv) &= ~CVf_CVGV_RC) 199 200 #ifdef PERL_CORE 201 # define CvSLABBED(cv) (CvFLAGS(cv) & CVf_SLABBED) 202 # define CvSLABBED_on(cv) (CvFLAGS(cv) |= CVf_SLABBED) 203 # define CvSLABBED_off(cv) (CvFLAGS(cv) &= ~CVf_SLABBED) 204 #endif 205 206 #define CvDYNFILE(cv) (CvFLAGS(cv) & CVf_DYNFILE) 207 #define CvDYNFILE_on(cv) (CvFLAGS(cv) |= CVf_DYNFILE) 208 #define CvDYNFILE_off(cv) (CvFLAGS(cv) &= ~CVf_DYNFILE) 209 210 #define CvAUTOLOAD(cv) (CvFLAGS(cv) & CVf_AUTOLOAD) 211 #define CvAUTOLOAD_on(cv) (CvFLAGS(cv) |= CVf_AUTOLOAD) 212 #define CvAUTOLOAD_off(cv) (CvFLAGS(cv) &= ~CVf_AUTOLOAD) 213 214 #define CvHASEVAL(cv) (CvFLAGS(cv) & CVf_HASEVAL) 215 #define CvHASEVAL_on(cv) (CvFLAGS(cv) |= CVf_HASEVAL) 216 #define CvHASEVAL_off(cv) (CvFLAGS(cv) &= ~CVf_HASEVAL) 217 218 #define CvNAMED(cv) (CvFLAGS(cv) & CVf_NAMED) 219 #define CvNAMED_on(cv) (CvFLAGS(cv) |= CVf_NAMED) 220 #define CvNAMED_off(cv) (CvFLAGS(cv) &= ~CVf_NAMED) 221 222 #define CvLEXICAL(cv) (CvFLAGS(cv) & CVf_LEXICAL) 223 #define CvLEXICAL_on(cv) (CvFLAGS(cv) |= CVf_LEXICAL) 224 #define CvLEXICAL_off(cv) (CvFLAGS(cv) &= ~CVf_LEXICAL) 225 226 #define CvANONCONST(cv) (CvFLAGS(cv) & CVf_ANONCONST) 227 #define CvANONCONST_on(cv) (CvFLAGS(cv) |= CVf_ANONCONST) 228 #define CvANONCONST_off(cv) (CvFLAGS(cv) &= ~CVf_ANONCONST) 229 230 #define CvSIGNATURE(cv) (CvFLAGS(cv) & CVf_SIGNATURE) 231 #define CvSIGNATURE_on(cv) (CvFLAGS(cv) |= CVf_SIGNATURE) 232 #define CvSIGNATURE_off(cv) (CvFLAGS(cv) &= ~CVf_SIGNATURE) 233 234 /* 235 236 =for apidoc m|bool|CvREFCOUNTED_ANYSV|CV *cv 237 238 If true, indicates that the C<CvXSUBANY(cv).any_sv> member contains an SV 239 pointer whose reference count should be decremented when the CV itself is 240 freed. In addition, C<cv_clone()> will increment the reference count, and 241 C<sv_dup()> will duplicate the entire pointed-to SV if this flag is set. 242 243 Any CV that wraps an XSUB has an C<ANY> union that the XSUB function is free 244 to use for its own purposes. It may be the case that the code wishes to store 245 an SV in the C<any_sv> member of this union. By setting this flag, this SV 246 reference will be properly reclaimed or duplicated when the CV itself is. 247 248 =for apidoc m|void|CvREFCOUNTED_ANYSV_on|CV *cv 249 250 Helper macro to turn on the C<CvREFCOUNTED_ANYSV> flag. 251 252 =for apidoc m|void|CvREFCOUNTED_ANYSV_off|CV *cv 253 254 Helper macro to turn off the C<CvREFCOUNTED_ANYSV> flag. 255 256 =cut 257 */ 258 259 #define CvREFCOUNTED_ANYSV(cv) (CvFLAGS(cv) & CVf_REFCOUNTED_ANYSV) 260 #define CvREFCOUNTED_ANYSV_on(cv) (CvFLAGS(cv) |= CVf_REFCOUNTED_ANYSV) 261 #define CvREFCOUNTED_ANYSV_off(cv) (CvFLAGS(cv) &= ~CVf_REFCOUNTED_ANYSV) 262 263 #define CvIsMETHOD(cv) (CvFLAGS(cv) & CVf_IsMETHOD) 264 #define CvIsMETHOD_on(cv) (CvFLAGS(cv) |= CVf_IsMETHOD) 265 #define CvIsMETHOD_off(cv) (CvFLAGS(cv) &= ~CVf_IsMETHOD) 266 267 /* Back-compat */ 268 #ifndef PERL_CORE 269 # define CVf_METHOD CVf_NOWARN_AMBIGUOUS 270 # define CvMETHOD(cv) CvNOWARN_AMBIGUOUS(cv) 271 # define CvMETHOD_on(cv) CvNOWARN_AMBIGUOUS_on(cv) 272 # define CvMETHOD_off(cv) CvNOWARN_AMBIGUOUS_off(cv) 273 #endif 274 275 /* Flags for newXS_flags */ 276 #define XS_DYNAMIC_FILENAME 0x01 /* The filename isn't static */ 277 278 PERL_STATIC_INLINE HEK * 279 CvNAME_HEK(CV *sv) 280 { 281 return CvNAMED(sv) 282 ? ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_gv_u.xcv_hek 283 : 0; 284 } 285 286 /* helper for the common pattern: 287 CvNAMED(sv) ? CvNAME_HEK((CV *)sv) : GvNAME_HEK(CvGV(sv)) 288 */ 289 #define CvGvNAME_HEK(sv) ( \ 290 CvNAMED((CV*)sv) ? \ 291 ((XPVCV*)MUTABLE_PTR(SvANY((SV*)sv)))->xcv_gv_u.xcv_hek\ 292 : GvNAME_HEK(CvGV( (SV*) sv)) \ 293 ) 294 295 /* This lowers the reference count of the previous value, but does *not* 296 increment the reference count of the new value. */ 297 #define CvNAME_HEK_set(cv, hek) ( \ 298 CvNAME_HEK((CV *)(cv)) \ 299 ? unshare_hek(SvANY((CV *)(cv))->xcv_gv_u.xcv_hek) \ 300 : (void)0, \ 301 ((XPVCV*)MUTABLE_PTR(SvANY(cv)))->xcv_gv_u.xcv_hek = (hek), \ 302 CvNAMED_on(cv) \ 303 ) 304 305 /* 306 307 =for apidoc m|bool|CvWEAKOUTSIDE|CV *cv 308 309 Each CV has a pointer, C<CvOUTSIDE()>, to its lexically enclosing 310 CV (if any). Because pointers to anonymous sub prototypes are 311 stored in C<&> pad slots, it is a possible to get a circular reference, 312 with the parent pointing to the child and vice-versa. To avoid the 313 ensuing memory leak, we do not increment the reference count of the CV 314 pointed to by C<CvOUTSIDE> in the I<one specific instance> that the parent 315 has a C<&> pad slot pointing back to us. In this case, we set the 316 C<CvWEAKOUTSIDE> flag in the child. This allows us to determine under what 317 circumstances we should decrement the refcount of the parent when freeing 318 the child. 319 320 There is a further complication with non-closure anonymous subs (i.e. those 321 that do not refer to any lexicals outside that sub). In this case, the 322 anonymous prototype is shared rather than being cloned. This has the 323 consequence that the parent may be freed while there are still active 324 children, I<e.g.>, 325 326 BEGIN { $a = sub { eval '$x' } } 327 328 In this case, the BEGIN is freed immediately after execution since there 329 are no active references to it: the anon sub prototype has 330 C<CvWEAKOUTSIDE> set since it's not a closure, and $a points to the same 331 CV, so it doesn't contribute to BEGIN's refcount either. When $a is 332 executed, the C<eval '$x'> causes the chain of C<CvOUTSIDE>s to be followed, 333 and the freed BEGIN is accessed. 334 335 To avoid this, whenever a CV and its associated pad is freed, any 336 C<&> entries in the pad are explicitly removed from the pad, and if the 337 refcount of the pointed-to anon sub is still positive, then that 338 child's C<CvOUTSIDE> is set to point to its grandparent. This will only 339 occur in the single specific case of a non-closure anon prototype 340 having one or more active references (such as C<$a> above). 341 342 One other thing to consider is that a CV may be merely undefined 343 rather than freed, eg C<undef &foo>. In this case, its refcount may 344 not have reached zero, but we still delete its pad and its C<CvROOT> etc. 345 Since various children may still have their C<CvOUTSIDE> pointing at this 346 undefined CV, we keep its own C<CvOUTSIDE> for the time being, so that 347 the chain of lexical scopes is unbroken. For example, the following 348 should print 123: 349 350 my $x = 123; 351 sub tmp { sub { eval '$x' } } 352 my $a = tmp(); 353 undef &tmp; 354 print $a->(); 355 356 =cut 357 */ 358 359 typedef OP *(*Perl_call_checker)(pTHX_ OP *, GV *, SV *); 360 361 #define CALL_CHECKER_REQUIRE_GV MGf_REQUIRE_GV 362 363 #define CV_NAME_NOTQUAL 1 364 365 #ifdef PERL_CORE 366 # define CV_UNDEF_KEEP_NAME 1 367 #endif 368 369 /* 370 * ex: set ts=8 sts=4 sw=4 et: 371 */ 372