1/* pad.h 2 * 3 * Copyright (C) 2002, by Larry Wall and others 4 * 5 * You may distribute under the terms of either the GNU General Public 6 * License or the Artistic License, as specified in the README file. 7 * 8 * This file defines the types and macros associated with the API for 9 * manipulating scratchpads, which are used by perl to store lexical 10 * variables, op targets and constants. 11 */ 12 13 14 15 16/* a padlist is currently just an AV; but that might change, 17 * so hide the type. Ditto a pad. */ 18 19typedef AV PADLIST; 20typedef AV PAD; 21 22 23/* offsets within a pad */ 24 25#if PTRSIZE == 4 26typedef U32TYPE PADOFFSET; 27#else 28# if PTRSIZE == 8 29typedef U64TYPE PADOFFSET; 30# endif 31#endif 32#define NOT_IN_PAD ((PADOFFSET) -1) 33 34 35/* flags for the pad_new() function */ 36 37#define padnew_CLONE 1 /* this pad is for a cloned CV */ 38#define padnew_SAVE 2 /* save old globals */ 39#define padnew_SAVESUB 4 /* also save extra stuff for start of sub */ 40 41/* values for the pad_tidy() function */ 42 43typedef enum { 44 padtidy_SUB, /* tidy up a pad for a sub, */ 45 padtidy_SUBCLONE, /* a cloned sub, */ 46 padtidy_FORMAT /* or a format */ 47} padtidy_type; 48 49/* ASSERT_CURPAD_LEGAL and ASSERT_CURPAD_ACTIVE respectively determine 50 * whether PL_comppad and PL_curpad are consistent and whether they have 51 * active values */ 52 53#ifdef DEBUGGING 54# define ASSERT_CURPAD_LEGAL(label) \ 55 if (PL_comppad ? (AvARRAY(PL_comppad) != PL_curpad) : (PL_curpad != 0)) \ 56 Perl_croak(aTHX_ "panic: illegal pad in %s: 0x%"UVxf"[0x%"UVxf"]",\ 57 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad)); 58 59 60# define ASSERT_CURPAD_ACTIVE(label) \ 61 if (!PL_comppad || (AvARRAY(PL_comppad) != PL_curpad)) \ 62 Perl_croak(aTHX_ "panic: invalid pad in %s: 0x%"UVxf"[0x%"UVxf"]",\ 63 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad)); 64#else 65# define ASSERT_CURPAD_LEGAL(label) 66# define ASSERT_CURPAD_ACTIVE(label) 67#endif 68 69 70 71/* Note: the following three macros are actually defined in scope.h, but 72 * they are documented here for completeness, since they directly or 73 * indirectly affect pads. 74 75=for apidoc m|void|SAVEPADSV |PADOFFSET po 76Save a pad slot (used to restore after an iteration) 77 78XXX DAPM it would make more sense to make the arg a PADOFFSET 79=for apidoc m|void|SAVECLEARSV |SV **svp 80Clear the pointed to pad value on scope exit. (ie the runtime action of 'my') 81 82=for apidoc m|void|SAVECOMPPAD 83save PL_comppad and PL_curpad 84 85 86 87 88 89=for apidoc m|SV *|PAD_SETSV |PADOFFSET po|SV* sv 90Set the slot at offset C<po> in the current pad to C<sv> 91 92=for apidoc m|void|PAD_SV |PADOFFSET po 93Get the value at offset C<po> in the current pad 94 95=for apidoc m|SV *|PAD_SVl |PADOFFSET po 96Lightweight and lvalue version of C<PAD_SV>. 97Get or set the value at offset C<po> in the current pad. 98Unlike C<PAD_SV>, does not print diagnostics with -DX. 99For internal use only. 100 101=for apidoc m|SV *|PAD_BASE_SV |PADLIST padlist|PADOFFSET po 102Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist 103 104=for apidoc m|void|PAD_SET_CUR |PADLIST padlist|I32 n 105Set the current pad to be pad C<n> in the padlist, saving 106the previous current pad. 107 108=for apidoc m|void|PAD_SET_CUR_NOSAVE |PADLIST padlist|I32 n 109like PAD_SET_CUR, but without the save 110 111=for apidoc m|void|PAD_SAVE_SETNULLPAD 112Save the current pad then set it to null. 113 114=for apidoc m|void|PAD_SAVE_LOCAL|PAD *opad|PAD *npad 115Save the current pad to the local variable opad, then make the 116current pad equal to npad 117 118=for apidoc m|void|PAD_RESTORE_LOCAL|PAD *opad 119Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL() 120 121=cut 122*/ 123 124#ifdef DEBUGGING 125# define PAD_SV(po) pad_sv(po) 126# define PAD_SETSV(po,sv) pad_setsv(po,sv) 127#else 128# define PAD_SV(po) (PL_curpad[po]) 129# define PAD_SETSV(po,sv) PL_curpad[po] = (sv) 130#endif 131 132#define PAD_SVl(po) (PL_curpad[po]) 133 134#define PAD_BASE_SV(padlist, po) \ 135 (AvARRAY(padlist)[1]) \ 136 ? AvARRAY((AV*)(AvARRAY(padlist)[1]))[po] : Nullsv; 137 138 139#define PAD_SET_CUR_NOSAVE(padlist,n) \ 140 PL_comppad = (PAD*) (AvARRAY(padlist)[n]); \ 141 PL_curpad = AvARRAY(PL_comppad); \ 142 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \ 143 "Pad 0x%"UVxf"[0x%"UVxf"] set_cur depth=%d\n", \ 144 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (int)(n))); 145 146 147#define PAD_SET_CUR(padlist,n) \ 148 SAVECOMPPAD(); \ 149 PAD_SET_CUR_NOSAVE(padlist,n); 150 151 152#define PAD_SAVE_SETNULLPAD() SAVECOMPPAD(); \ 153 PL_comppad = Null(PAD*); PL_curpad = Null(SV**); \ 154 DEBUG_Xv(PerlIO_printf(Perl_debug_log, "Pad set_null\n")); 155 156#define PAD_SAVE_LOCAL(opad,npad) \ 157 opad = PL_comppad; \ 158 PL_comppad = (npad); \ 159 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : Null(SV**); \ 160 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \ 161 "Pad 0x%"UVxf"[0x%"UVxf"] save_local\n", \ 162 PTR2UV(PL_comppad), PTR2UV(PL_curpad))); 163 164#define PAD_RESTORE_LOCAL(opad) \ 165 PL_comppad = opad; \ 166 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : Null(SV**); \ 167 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \ 168 "Pad 0x%"UVxf"[0x%"UVxf"] restore_local\n", \ 169 PTR2UV(PL_comppad), PTR2UV(PL_curpad))); 170 171 172/* 173=for apidoc m|void|CX_CURPAD_SAVE|struct context 174Save the current pad in the given context block structure. 175 176=for apidoc m|SV *|CX_CURPAD_SV|struct context|PADOFFSET po 177Access the SV at offset po in the saved current pad in the given 178context block structure (can be used as an lvalue). 179 180=cut 181*/ 182 183#define CX_CURPAD_SAVE(block) (block).oldcomppad = PL_comppad 184#define CX_CURPAD_SV(block,po) (AvARRAY((AV*)((block).oldcomppad))[po]) 185 186 187/* 188=for apidoc m|U32|PAD_COMPNAME_FLAGS|PADOFFSET po 189Return the flags for the current compiling pad name 190at offset C<po>. Assumes a valid slot entry. 191 192=for apidoc m|char *|PAD_COMPNAME_PV|PADOFFSET po 193Return the name of the current compiling pad name 194at offset C<po>. Assumes a valid slot entry. 195 196=for apidoc m|HV *|PAD_COMPNAME_TYPE|PADOFFSET po 197Return the type (stash) of the current compiling pad name at offset 198C<po>. Must be a valid name. Returns null if not typed. 199 200=for apidoc m|HV *|PAD_COMPNAME_OURSTASH|PADOFFSET po 201Return the stash associated with an C<our> variable. 202Assumes the slot entry is a valid C<our> lexical. 203 204=for apidoc m|STRLEN|PAD_COMPNAME_GEN|PADOFFSET po 205The generation number of the name at offset C<po> in the current 206compiling pad (lvalue). Note that C<SvCUR> is hijacked for this purpose. 207 208=cut 209*/ 210 211#define PAD_COMPNAME_FLAGS(po) SvFLAGS(*av_fetch(PL_comppad_name, (po), FALSE)) 212#define PAD_COMPNAME_PV(po) SvPV_nolen(*av_fetch(PL_comppad_name, (po), FALSE)) 213 214/* XXX DAPM yuk - using av_fetch twice. Is there a better way? */ 215#define PAD_COMPNAME_TYPE(po) \ 216 ((SvFLAGS(*av_fetch(PL_comppad_name, (po), FALSE)) & SVpad_TYPED) \ 217 ? (SvSTASH(*av_fetch(PL_comppad_name, (po), FALSE))) : Nullhv) 218 219#define PAD_COMPNAME_OURSTASH(po) \ 220 (GvSTASH(*av_fetch(PL_comppad_name, (po), FALSE))) 221 222#define PAD_COMPNAME_GEN(po) SvCUR(AvARRAY(PL_comppad_name)[po]) 223 224 225 226 227/* 228=for apidoc m|void|PAD_DUP|PADLIST dstpad|PADLIST srcpad|CLONE_PARAMS* param 229Clone a padlist. 230 231=for apidoc m|void|PAD_CLONE_VARS|PerlInterpreter *proto_perl \ 232|CLONE_PARAMS* param 233Clone the state variables associated with running and compiling pads. 234 235=cut 236*/ 237 238 239#define PAD_DUP(dstpad, srcpad, param) \ 240 if ((srcpad) && !AvREAL(srcpad)) { \ 241 /* XXX padlists are real, but pretend to be not */ \ 242 AvREAL_on(srcpad); \ 243 (dstpad) = av_dup_inc((srcpad), param); \ 244 AvREAL_off(srcpad); \ 245 AvREAL_off(dstpad); \ 246 } \ 247 else \ 248 (dstpad) = av_dup_inc((srcpad), param); 249 250/* NB - we set PL_comppad to null unless it points at a value that 251 * has already been dup'ed, ie it points to part of an active padlist. 252 * Otherwise PL_comppad ends up being a leaked scalar in code like 253 * the following: 254 * threads->create(sub { threads->create(sub {...} ) } ); 255 * where the second thread dups the outer sub's comppad but not the 256 * sub's CV or padlist. */ 257 258#define PAD_CLONE_VARS(proto_perl, param) \ 259 PL_comppad = ptr_table_fetch(PL_ptr_table, proto_perl->Tcomppad); \ 260 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : Null(SV**); \ 261 PL_comppad_name = av_dup(proto_perl->Icomppad_name, param); \ 262 PL_comppad_name_fill = proto_perl->Icomppad_name_fill; \ 263 PL_comppad_name_floor = proto_perl->Icomppad_name_floor; \ 264 PL_min_intro_pending = proto_perl->Imin_intro_pending; \ 265 PL_max_intro_pending = proto_perl->Imax_intro_pending; \ 266 PL_padix = proto_perl->Ipadix; \ 267 PL_padix_floor = proto_perl->Ipadix_floor; \ 268 PL_pad_reset_pending = proto_perl->Ipad_reset_pending; \ 269 PL_cop_seqmax = proto_perl->Icop_seqmax; 270