3 * Copyright (C) 2002, by Larry Wall and others
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.
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.
16 /* a padlist is currently just an AV; but that might change,
17 * so hide the type. Ditto a pad. */
23 /* offsets within a pad */
26 typedef U32TYPE PADOFFSET;
29 typedef U64TYPE PADOFFSET;
32 #define NOT_IN_PAD ((PADOFFSET) -1)
35 /* flags for the pad_new() function */
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 */
41 /* values for the pad_tidy() function */
44 padtidy_SUB, /* tidy up a pad for a sub, */
45 padtidy_SUBCLONE, /* a cloned sub, */
46 padtidy_FORMAT /* or a format */
49 /* ASSERT_CURPAD_LEGAL and ASSERT_CURPAD_ACTIVE respectively determine
50 * whether PL_comppad and PL_curpad are consistent and whether they have
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));
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));
65 # define ASSERT_CURPAD_LEGAL(label)
66 # define ASSERT_CURPAD_ACTIVE(label)
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.
75 =for apidoc m|void|SAVEPADSV |PADOFFSET po
76 Save a pad slot (used to restore after an iteration)
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. (ie the runtime action of 'my')
82 =for apidoc m|void|SAVECOMPPAD
83 save PL_comppad and PL_curpad
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>
92 =for apidoc m|void|PAD_SV |PADOFFSET po
93 Get the value at offset C<po> in the current pad
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.
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
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.
108 =for apidoc m|void|PAD_SET_CUR_NOSAVE |PADLIST padlist|I32 n
109 like PAD_SET_CUR, but without the save
111 =for apidoc m|void|PAD_SAVE_SETNULLPAD
112 Save the current pad then set it to null.
114 =for apidoc m|void|PAD_SAVE_LOCAL|PAD *opad|PAD *npad
115 Save the current pad to the local variable opad, then make the
116 current pad equal to npad
118 =for apidoc m|void|PAD_RESTORE_LOCAL|PAD *opad
119 Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL()
125 # define PAD_SV(po) pad_sv(po)
126 # define PAD_SETSV(po,sv) pad_setsv(po,sv)
128 # define PAD_SV(po) (PL_curpad[po])
129 # define PAD_SETSV(po,sv) PL_curpad[po] = (sv)
132 #define PAD_SVl(po) (PL_curpad[po])
134 #define PAD_BASE_SV(padlist, po) \
135 (AvARRAY(padlist)[1]) \
136 ? AvARRAY((AV*)(AvARRAY(padlist)[1]))[po] : Nullsv;
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)));
147 #define PAD_SET_CUR(padlist,n) \
149 PAD_SET_CUR_NOSAVE(padlist,n);
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"));
156 #define PAD_SAVE_LOCAL(opad,npad) \
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)));
164 #define PAD_RESTORE_LOCAL(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)));
173 =for apidoc m|void|CX_CURPAD_SAVE|struct context
174 Save the current pad in the given context block structure.
176 =for apidoc m|SV *|CX_CURPAD_SV|struct context|PADOFFSET po
177 Access the SV at offset po in the saved current pad in the given
178 context block structure (can be used as an lvalue).
183 #define CX_CURPAD_SAVE(block) (block).oldcomppad = PL_comppad
184 #define CX_CURPAD_SV(block,po) (AvARRAY((AV*)((block).oldcomppad))[po])
188 =for apidoc m|U32|PAD_COMPNAME_FLAGS|PADOFFSET po
189 Return the flags for the current compiling pad name
190 at offset C<po>. Assumes a valid slot entry.
192 =for apidoc m|char *|PAD_COMPNAME_PV|PADOFFSET po
193 Return the name of the current compiling pad name
194 at offset C<po>. Assumes a valid slot entry.
196 =for apidoc m|HV *|PAD_COMPNAME_TYPE|PADOFFSET po
197 Return the type (stash) of the current compiling pad name at offset
198 C<po>. Must be a valid name. Returns null if not typed.
200 =for apidoc m|HV *|PAD_COMPNAME_OURSTASH|PADOFFSET po
201 Return the stash associated with an C<our> variable.
202 Assumes the slot entry is a valid C<our> lexical.
204 =for apidoc m|STRLEN|PAD_COMPNAME_GEN|PADOFFSET po
205 The generation number of the name at offset C<po> in the current
206 compiling pad (lvalue). Note that C<SvCUR> is hijacked for this purpose.
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))
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)
219 #define PAD_COMPNAME_OURSTASH(po) \
220 (GvSTASH(*av_fetch(PL_comppad_name, (po), FALSE)))
222 #define PAD_COMPNAME_GEN(po) SvCUR(AvARRAY(PL_comppad_name)[po])
228 =for apidoc m|void|PAD_DUP|PADLIST dstpad|PADLIST srcpad|CLONE_PARAMS* param
231 =for apidoc m|void|PAD_CLONE_VARS|PerlInterpreter *proto_perl \
233 Clone the state variables associated with running and compiling pads.
239 #define PAD_DUP(dstpad, srcpad, param) \
240 if ((srcpad) && !AvREAL(srcpad)) { \
241 /* XXX padlists are real, but pretend to be not */ \
243 (dstpad) = av_dup_inc((srcpad), param); \
244 AvREAL_off(srcpad); \
245 AvREAL_off(dstpad); \
248 (dstpad) = av_dup_inc((srcpad), param);
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
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. */
258 #define PAD_CLONE_VARS(proto_perl, param) \
259 PL_comppad = ptr_table_fetch(PL_ptr_table, proto_perl->Icomppad); \
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;