1 /* pad.h 2 * 3 * Copyright (C) 2002, 2003, 2005, 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 19 typedef AV PADLIST; 20 typedef AV PAD; 21 22 23 /* offsets within a pad */ 24 25 #if PTRSIZE == 4 26 typedef U32TYPE PADOFFSET; 27 #else 28 # if PTRSIZE == 8 29 typedef 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 43 typedef 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 76 Save a pad slot (used to restore after an iteration) 77 78 XXX DAPM it would make more sense to make the arg a PADOFFSET 79 =for apidoc m|void|SAVECLEARSV |SV **svp 80 Clear the pointed to pad value on scope exit. (i.e. the runtime action of 'my') 81 82 =for apidoc m|void|SAVECOMPPAD 83 save PL_comppad and PL_curpad 84 85 86 87 88 89 =for apidoc m|SV *|PAD_SETSV |PADOFFSET po|SV* sv 90 Set the slot at offset C<po> in the current pad to C<sv> 91 92 =for apidoc m|void|PAD_SV |PADOFFSET po 93 Get the value at offset C<po> in the current pad 94 95 =for apidoc m|SV *|PAD_SVl |PADOFFSET po 96 Lightweight and lvalue version of C<PAD_SV>. 97 Get or set the value at offset C<po> in the current pad. 98 Unlike C<PAD_SV>, does not print diagnostics with -DX. 99 For internal use only. 100 101 =for apidoc m|SV *|PAD_BASE_SV |PADLIST padlist|PADOFFSET po 102 Get 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 105 Set the current pad to be pad C<n> in the padlist, saving 106 the previous current pad. NB currently this macro expands to a string too 107 long for some compilers, so it's best to replace it with 108 109 SAVECOMPPAD(); 110 PAD_SET_CUR_NOSAVE(padlist,n); 111 112 113 =for apidoc m|void|PAD_SET_CUR_NOSAVE |PADLIST padlist|I32 n 114 like PAD_SET_CUR, but without the save 115 116 =for apidoc m|void|PAD_SAVE_SETNULLPAD 117 Save the current pad then set it to null. 118 119 =for apidoc m|void|PAD_SAVE_LOCAL|PAD *opad|PAD *npad 120 Save the current pad to the local variable opad, then make the 121 current pad equal to npad 122 123 =for apidoc m|void|PAD_RESTORE_LOCAL|PAD *opad 124 Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL() 125 126 =cut 127 */ 128 129 #ifdef DEBUGGING 130 # define PAD_SV(po) pad_sv(po) 131 # define PAD_SETSV(po,sv) pad_setsv(po,sv) 132 #else 133 # define PAD_SV(po) (PL_curpad[po]) 134 # define PAD_SETSV(po,sv) PL_curpad[po] = (sv) 135 #endif 136 137 #define PAD_SVl(po) (PL_curpad[po]) 138 139 #define PAD_BASE_SV(padlist, po) \ 140 (AvARRAY(padlist)[1]) \ 141 ? AvARRAY((AV*)(AvARRAY(padlist)[1]))[po] : Nullsv; 142 143 144 #define PAD_SET_CUR_NOSAVE(padlist,n) \ 145 PL_comppad = (PAD*) (AvARRAY(padlist)[n]); \ 146 PL_curpad = AvARRAY(PL_comppad); \ 147 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \ 148 "Pad 0x%"UVxf"[0x%"UVxf"] set_cur depth=%d\n", \ 149 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (int)(n))); 150 151 152 #define PAD_SET_CUR(padlist,n) \ 153 SAVECOMPPAD(); \ 154 PAD_SET_CUR_NOSAVE(padlist,n); 155 156 157 #define PAD_SAVE_SETNULLPAD() SAVECOMPPAD(); \ 158 PL_comppad = Null(PAD*); PL_curpad = Null(SV**); \ 159 DEBUG_Xv(PerlIO_printf(Perl_debug_log, "Pad set_null\n")); 160 161 #define PAD_SAVE_LOCAL(opad,npad) \ 162 opad = PL_comppad; \ 163 PL_comppad = (npad); \ 164 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : Null(SV**); \ 165 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \ 166 "Pad 0x%"UVxf"[0x%"UVxf"] save_local\n", \ 167 PTR2UV(PL_comppad), PTR2UV(PL_curpad))); 168 169 #define PAD_RESTORE_LOCAL(opad) \ 170 PL_comppad = opad; \ 171 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : Null(SV**); \ 172 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \ 173 "Pad 0x%"UVxf"[0x%"UVxf"] restore_local\n", \ 174 PTR2UV(PL_comppad), PTR2UV(PL_curpad))); 175 176 177 /* 178 =for apidoc m|void|CX_CURPAD_SAVE|struct context 179 Save the current pad in the given context block structure. 180 181 =for apidoc m|SV *|CX_CURPAD_SV|struct context|PADOFFSET po 182 Access the SV at offset po in the saved current pad in the given 183 context block structure (can be used as an lvalue). 184 185 =cut 186 */ 187 188 #define CX_CURPAD_SAVE(block) (block).oldcomppad = PL_comppad 189 #define CX_CURPAD_SV(block,po) (AvARRAY((AV*)((block).oldcomppad))[po]) 190 191 192 /* 193 =for apidoc m|U32|PAD_COMPNAME_FLAGS|PADOFFSET po 194 Return the flags for the current compiling pad name 195 at offset C<po>. Assumes a valid slot entry. 196 197 =for apidoc m|char *|PAD_COMPNAME_PV|PADOFFSET po 198 Return the name of the current compiling pad name 199 at offset C<po>. Assumes a valid slot entry. 200 201 =for apidoc m|HV *|PAD_COMPNAME_TYPE|PADOFFSET po 202 Return the type (stash) of the current compiling pad name at offset 203 C<po>. Must be a valid name. Returns null if not typed. 204 205 =for apidoc m|HV *|PAD_COMPNAME_OURSTASH|PADOFFSET po 206 Return the stash associated with an C<our> variable. 207 Assumes the slot entry is a valid C<our> lexical. 208 209 =for apidoc m|STRLEN|PAD_COMPNAME_GEN|PADOFFSET po 210 The generation number of the name at offset C<po> in the current 211 compiling pad (lvalue). Note that C<SvCUR> is hijacked for this purpose. 212 213 =for apidoc m|STRLEN|PAD_COMPNAME_GEN_set|PADOFFSET po|int gen 214 Sets the generation number of the name at offset C<po> in the current 215 ling pad (lvalue) to C<gen>. Note that C<SvCUR_set> is hijacked for this purpose. 216 217 =cut 218 219 */ 220 221 #define PAD_COMPNAME_FLAGS(po) SvFLAGS(*av_fetch(PL_comppad_name, (po), FALSE)) 222 #define PAD_COMPNAME_PV(po) SvPV_nolen(*av_fetch(PL_comppad_name, (po), FALSE)) 223 224 #define PAD_COMPNAME_TYPE(po) pad_compname_type(po) 225 226 #define PAD_COMPNAME_OURSTASH(po) \ 227 (GvSTASH(*av_fetch(PL_comppad_name, (po), FALSE))) 228 229 #define PAD_COMPNAME_GEN(po) SvCUR(AvARRAY(PL_comppad_name)[po]) 230 231 #define PAD_COMPNAME_GEN_set(po, gen) SvCUR_set(AvARRAY(PL_comppad_name)[po], gen) 232 233 234 /* 235 =for apidoc m|void|PAD_DUP|PADLIST dstpad|PADLIST srcpad|CLONE_PARAMS* param 236 Clone a padlist. 237 238 =for apidoc m|void|PAD_CLONE_VARS|PerlInterpreter *proto_perl \ 239 |CLONE_PARAMS* param 240 Clone the state variables associated with running and compiling pads. 241 242 =cut 243 */ 244 245 246 #define PAD_DUP(dstpad, srcpad, param) \ 247 if ((srcpad) && !AvREAL(srcpad)) { \ 248 /* XXX padlists are real, but pretend to be not */ \ 249 AvREAL_on(srcpad); \ 250 (dstpad) = av_dup_inc((srcpad), param); \ 251 AvREAL_off(srcpad); \ 252 AvREAL_off(dstpad); \ 253 } \ 254 else \ 255 (dstpad) = av_dup_inc((srcpad), param); 256 257 /* NB - we set PL_comppad to null unless it points at a value that 258 * has already been dup'ed, ie it points to part of an active padlist. 259 * Otherwise PL_comppad ends up being a leaked scalar in code like 260 * the following: 261 * threads->create(sub { threads->create(sub {...} ) } ); 262 * where the second thread dups the outer sub's comppad but not the 263 * sub's CV or padlist. */ 264 265 #define PAD_CLONE_VARS(proto_perl, param) \ 266 PL_comppad = ptr_table_fetch(PL_ptr_table, proto_perl->Tcomppad); \ 267 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : Null(SV**); \ 268 PL_comppad_name = av_dup(proto_perl->Icomppad_name, param); \ 269 PL_comppad_name_fill = proto_perl->Icomppad_name_fill; \ 270 PL_comppad_name_floor = proto_perl->Icomppad_name_floor; \ 271 PL_min_intro_pending = proto_perl->Imin_intro_pending; \ 272 PL_max_intro_pending = proto_perl->Imax_intro_pending; \ 273 PL_padix = proto_perl->Ipadix; \ 274 PL_padix_floor = proto_perl->Ipadix_floor; \ 275 PL_pad_reset_pending = proto_perl->Ipad_reset_pending; \ 276 PL_cop_seqmax = proto_perl->Icop_seqmax; 277