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 /* 0x4000 previously CVf_HASEVAL */ 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 #define CVf_XS_RCSTACK 0x200000 /* the XS function understands a 142 reference-counted stack */ 143 144 /* This symbol for optimised communication between toke.c and op.c: */ 145 #define CVf_BUILTIN_ATTRS (CVf_NOWARN_AMBIGUOUS|CVf_LVALUE|CVf_ANONCONST) 146 147 #define CvCLONE(cv) (CvFLAGS(cv) & CVf_CLONE) 148 #define CvCLONE_on(cv) (CvFLAGS(cv) |= CVf_CLONE) 149 #define CvCLONE_off(cv) (CvFLAGS(cv) &= ~CVf_CLONE) 150 151 #define CvCLONED(cv) (CvFLAGS(cv) & CVf_CLONED) 152 #define CvCLONED_on(cv) (CvFLAGS(cv) |= CVf_CLONED) 153 #define CvCLONED_off(cv) (CvFLAGS(cv) &= ~CVf_CLONED) 154 155 #define CvANON(cv) (CvFLAGS(cv) & CVf_ANON) 156 #define CvANON_on(cv) (CvFLAGS(cv) |= CVf_ANON) 157 #define CvANON_off(cv) (CvFLAGS(cv) &= ~CVf_ANON) 158 159 /* CvEVAL or CvSPECIAL */ 160 #define CvUNIQUE(cv) (CvFLAGS(cv) & CVf_UNIQUE) 161 #define CvUNIQUE_on(cv) (CvFLAGS(cv) |= CVf_UNIQUE) 162 #define CvUNIQUE_off(cv) (CvFLAGS(cv) &= ~CVf_UNIQUE) 163 164 #define CvNODEBUG(cv) (CvFLAGS(cv) & CVf_NODEBUG) 165 #define CvNODEBUG_on(cv) (CvFLAGS(cv) |= CVf_NODEBUG) 166 #define CvNODEBUG_off(cv) (CvFLAGS(cv) &= ~CVf_NODEBUG) 167 168 #define CvNOWARN_AMBIGUOUS(cv) (CvFLAGS(cv) & CVf_NOWARN_AMBIGUOUS) 169 #define CvNOWARN_AMBIGUOUS_on(cv) (CvFLAGS(cv) |= CVf_NOWARN_AMBIGUOUS) 170 #define CvNOWARN_AMBIGUOUS_off(cv) (CvFLAGS(cv) &= ~CVf_NOWARN_AMBIGUOUS) 171 172 #define CvLVALUE(cv) (CvFLAGS(cv) & CVf_LVALUE) 173 #define CvLVALUE_on(cv) (CvFLAGS(cv) |= CVf_LVALUE) 174 #define CvLVALUE_off(cv) (CvFLAGS(cv) &= ~CVf_LVALUE) 175 176 /* eval or PL_main_cv */ 177 #define CvEVAL(cv) (CvUNIQUE(cv) && !SvFAKE(cv)) 178 #define CvEVAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_off(cv)) 179 #define CvEVAL_off(cv) CvUNIQUE_off(cv) 180 181 /* BEGIN|CHECK|INIT|UNITCHECK|END */ 182 #define CvSPECIAL(cv) (CvUNIQUE(cv) && SvFAKE(cv)) 183 #define CvSPECIAL_on(cv) (CvUNIQUE_on(cv),SvFAKE_on(cv)) 184 #define CvSPECIAL_off(cv) (CvUNIQUE_off(cv),SvFAKE_off(cv)) 185 186 #define CvCONST(cv) (CvFLAGS(cv) & CVf_CONST) 187 #define CvCONST_on(cv) (CvFLAGS(cv) |= CVf_CONST) 188 #define CvCONST_off(cv) (CvFLAGS(cv) &= ~CVf_CONST) 189 190 #define CvWEAKOUTSIDE(cv) (CvFLAGS(cv) & CVf_WEAKOUTSIDE) 191 #define CvWEAKOUTSIDE_on(cv) (CvFLAGS(cv) |= CVf_WEAKOUTSIDE) 192 #define CvWEAKOUTSIDE_off(cv) (CvFLAGS(cv) &= ~CVf_WEAKOUTSIDE) 193 194 #define CvISXSUB(cv) (CvFLAGS(cv) & CVf_ISXSUB) 195 #define CvISXSUB_on(cv) (CvFLAGS(cv) |= CVf_ISXSUB) 196 #define CvISXSUB_off(cv) (CvFLAGS(cv) &= ~CVf_ISXSUB) 197 198 #define CvCVGV_RC(cv) (CvFLAGS(cv) & CVf_CVGV_RC) 199 #define CvCVGV_RC_on(cv) (CvFLAGS(cv) |= CVf_CVGV_RC) 200 #define CvCVGV_RC_off(cv) (CvFLAGS(cv) &= ~CVf_CVGV_RC) 201 202 #ifdef PERL_CORE 203 # define CvSLABBED(cv) (CvFLAGS(cv) & CVf_SLABBED) 204 # define CvSLABBED_on(cv) (CvFLAGS(cv) |= CVf_SLABBED) 205 # define CvSLABBED_off(cv) (CvFLAGS(cv) &= ~CVf_SLABBED) 206 #endif 207 208 #define CvDYNFILE(cv) (CvFLAGS(cv) & CVf_DYNFILE) 209 #define CvDYNFILE_on(cv) (CvFLAGS(cv) |= CVf_DYNFILE) 210 #define CvDYNFILE_off(cv) (CvFLAGS(cv) &= ~CVf_DYNFILE) 211 212 #define CvAUTOLOAD(cv) (CvFLAGS(cv) & CVf_AUTOLOAD) 213 #define CvAUTOLOAD_on(cv) (CvFLAGS(cv) |= CVf_AUTOLOAD) 214 #define CvAUTOLOAD_off(cv) (CvFLAGS(cv) &= ~CVf_AUTOLOAD) 215 216 #define CvNAMED(cv) (CvFLAGS(cv) & CVf_NAMED) 217 #define CvNAMED_on(cv) (CvFLAGS(cv) |= CVf_NAMED) 218 #define CvNAMED_off(cv) (CvFLAGS(cv) &= ~CVf_NAMED) 219 220 #define CvLEXICAL(cv) (CvFLAGS(cv) & CVf_LEXICAL) 221 #define CvLEXICAL_on(cv) (CvFLAGS(cv) |= CVf_LEXICAL) 222 #define CvLEXICAL_off(cv) (CvFLAGS(cv) &= ~CVf_LEXICAL) 223 224 #define CvANONCONST(cv) (CvFLAGS(cv) & CVf_ANONCONST) 225 #define CvANONCONST_on(cv) (CvFLAGS(cv) |= CVf_ANONCONST) 226 #define CvANONCONST_off(cv) (CvFLAGS(cv) &= ~CVf_ANONCONST) 227 228 #define CvSIGNATURE(cv) (CvFLAGS(cv) & CVf_SIGNATURE) 229 #define CvSIGNATURE_on(cv) (CvFLAGS(cv) |= CVf_SIGNATURE) 230 #define CvSIGNATURE_off(cv) (CvFLAGS(cv) &= ~CVf_SIGNATURE) 231 232 /* 233 234 =for apidoc m|bool|CvREFCOUNTED_ANYSV|CV *cv 235 236 If true, indicates that the C<CvXSUBANY(cv).any_sv> member contains an SV 237 pointer whose reference count should be decremented when the CV itself is 238 freed. In addition, C<cv_clone()> will increment the reference count, and 239 C<sv_dup()> will duplicate the entire pointed-to SV if this flag is set. 240 241 Any CV that wraps an XSUB has an C<ANY> union that the XSUB function is free 242 to use for its own purposes. It may be the case that the code wishes to store 243 an SV in the C<any_sv> member of this union. By setting this flag, this SV 244 reference will be properly reclaimed or duplicated when the CV itself is. 245 246 =for apidoc m|void|CvREFCOUNTED_ANYSV_on|CV *cv 247 248 Helper macro to turn on the C<CvREFCOUNTED_ANYSV> flag. 249 250 =for apidoc m|void|CvREFCOUNTED_ANYSV_off|CV *cv 251 252 Helper macro to turn off the C<CvREFCOUNTED_ANYSV> flag. 253 254 =cut 255 */ 256 257 #define CvREFCOUNTED_ANYSV(cv) (CvFLAGS(cv) & CVf_REFCOUNTED_ANYSV) 258 #define CvREFCOUNTED_ANYSV_on(cv) (CvFLAGS(cv) |= CVf_REFCOUNTED_ANYSV) 259 #define CvREFCOUNTED_ANYSV_off(cv) (CvFLAGS(cv) &= ~CVf_REFCOUNTED_ANYSV) 260 261 #define CvIsMETHOD(cv) (CvFLAGS(cv) & CVf_IsMETHOD) 262 #define CvIsMETHOD_on(cv) (CvFLAGS(cv) |= CVf_IsMETHOD) 263 #define CvIsMETHOD_off(cv) (CvFLAGS(cv) &= ~CVf_IsMETHOD) 264 265 #define CvXS_RCSTACK(cv) (CvFLAGS(cv) & CVf_XS_RCSTACK) 266 #define CvXS_RCSTACK_on(cv) (CvFLAGS(cv) |= CVf_XS_RCSTACK) 267 #define CvXS_RCSTACK_off(cv) (CvFLAGS(cv) &= ~CVf_XS_RCSTACK) 268 269 /* Back-compat */ 270 #ifndef PERL_CORE 271 # define CVf_METHOD CVf_NOWARN_AMBIGUOUS 272 # define CvMETHOD(cv) CvNOWARN_AMBIGUOUS(cv) 273 # define CvMETHOD_on(cv) CvNOWARN_AMBIGUOUS_on(cv) 274 # define CvMETHOD_off(cv) CvNOWARN_AMBIGUOUS_off(cv) 275 #endif 276 277 /* Flags for newXS_flags */ 278 #define XS_DYNAMIC_FILENAME 0x01 /* The filename isn't static */ 279 280 PERL_STATIC_INLINE HEK * 281 CvNAME_HEK(CV *sv) 282 { 283 return CvNAMED(sv) 284 ? ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_gv_u.xcv_hek 285 : 0; 286 } 287 288 /* helper for the common pattern: 289 CvNAMED(sv) ? CvNAME_HEK((CV *)sv) : GvNAME_HEK(CvGV(sv)) 290 */ 291 #define CvGvNAME_HEK(sv) ( \ 292 CvNAMED((CV*)sv) ? \ 293 ((XPVCV*)MUTABLE_PTR(SvANY((SV*)sv)))->xcv_gv_u.xcv_hek\ 294 : GvNAME_HEK(CvGV( (SV*) sv)) \ 295 ) 296 297 /* This lowers the reference count of the previous value, but does *not* 298 increment the reference count of the new value. */ 299 #define CvNAME_HEK_set(cv, hek) ( \ 300 CvNAME_HEK((CV *)(cv)) \ 301 ? unshare_hek(SvANY((CV *)(cv))->xcv_gv_u.xcv_hek) \ 302 : (void)0, \ 303 ((XPVCV*)MUTABLE_PTR(SvANY(cv)))->xcv_gv_u.xcv_hek = (hek), \ 304 CvNAMED_on(cv) \ 305 ) 306 307 /* 308 309 =for apidoc m|bool|CvWEAKOUTSIDE|CV *cv 310 311 Each CV has a pointer, C<CvOUTSIDE()>, to its lexically enclosing 312 CV (if any). Because pointers to anonymous sub prototypes are 313 stored in C<&> pad slots, it is a possible to get a circular reference, 314 with the parent pointing to the child and vice-versa. To avoid the 315 ensuing memory leak, we do not increment the reference count of the CV 316 pointed to by C<CvOUTSIDE> in the I<one specific instance> that the parent 317 has a C<&> pad slot pointing back to us. In this case, we set the 318 C<CvWEAKOUTSIDE> flag in the child. This allows us to determine under what 319 circumstances we should decrement the refcount of the parent when freeing 320 the child. 321 322 There is a further complication with non-closure anonymous subs (i.e. those 323 that do not refer to any lexicals outside that sub). In this case, the 324 anonymous prototype is shared rather than being cloned. This has the 325 consequence that the parent may be freed while there are still active 326 children, I<e.g.>, 327 328 BEGIN { $a = sub { eval '$x' } } 329 330 In this case, the BEGIN is freed immediately after execution since there 331 are no active references to it: the anon sub prototype has 332 C<CvWEAKOUTSIDE> set since it's not a closure, and $a points to the same 333 CV, so it doesn't contribute to BEGIN's refcount either. When $a is 334 executed, the C<eval '$x'> causes the chain of C<CvOUTSIDE>s to be followed, 335 and the freed BEGIN is accessed. 336 337 To avoid this, whenever a CV and its associated pad is freed, any 338 C<&> entries in the pad are explicitly removed from the pad, and if the 339 refcount of the pointed-to anon sub is still positive, then that 340 child's C<CvOUTSIDE> is set to point to its grandparent. This will only 341 occur in the single specific case of a non-closure anon prototype 342 having one or more active references (such as C<$a> above). 343 344 One other thing to consider is that a CV may be merely undefined 345 rather than freed, eg C<undef &foo>. In this case, its refcount may 346 not have reached zero, but we still delete its pad and its C<CvROOT> etc. 347 Since various children may still have their C<CvOUTSIDE> pointing at this 348 undefined CV, we keep its own C<CvOUTSIDE> for the time being, so that 349 the chain of lexical scopes is unbroken. For example, the following 350 should print 123: 351 352 my $x = 123; 353 sub tmp { sub { eval '$x' } } 354 my $a = tmp(); 355 undef &tmp; 356 print $a->(); 357 358 =cut 359 */ 360 361 typedef OP *(*Perl_call_checker)(pTHX_ OP *, GV *, SV *); 362 363 #define CALL_CHECKER_REQUIRE_GV MGf_REQUIRE_GV 364 365 #define CV_NAME_NOTQUAL 1 366 367 #ifdef PERL_CORE 368 # define CV_UNDEF_KEEP_NAME 1 369 #endif 370 371 /* 372 * ex: set ts=8 sts=4 sw=4 et: 373 */ 374