lib/perl5/5.8.8/msys/CORE/pad.h

   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;