This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Integrate:
[perl5.git] / scope.h
CommitLineData
d6376244
JH
1/* scope.h
2 *
3 * Copyright (c) 1997-2002, Larry Wall
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 */
9
b9d12d37
GS
10#define SAVEt_ITEM 0
11#define SAVEt_SV 1
12#define SAVEt_AV 2
13#define SAVEt_HV 3
14#define SAVEt_INT 4
15#define SAVEt_LONG 5
16#define SAVEt_I32 6
17#define SAVEt_IV 7
18#define SAVEt_SPTR 8
19#define SAVEt_APTR 9
20#define SAVEt_HPTR 10
21#define SAVEt_PPTR 11
22#define SAVEt_NSTAB 12
23#define SAVEt_SVREF 13
24#define SAVEt_GP 14
25#define SAVEt_FREESV 15
26#define SAVEt_FREEOP 16
27#define SAVEt_FREEPV 17
28#define SAVEt_CLEARSV 18
29#define SAVEt_DELETE 19
30#define SAVEt_DESTRUCTOR 20
31#define SAVEt_REGCONTEXT 21
32#define SAVEt_STACK_POS 22
33#define SAVEt_I16 23
34#define SAVEt_AELEM 24
35#define SAVEt_HELEM 25
36#define SAVEt_OP 26
37#define SAVEt_HINTS 27
38#define SAVEt_ALLOC 28
39#define SAVEt_GENERIC_SVREF 29
c76ac1ee 40#define SAVEt_DESTRUCTOR_X 30
7766f137 41#define SAVEt_VPTR 31
e8347627 42#define SAVEt_I8 32
354992b1 43#define SAVEt_COMPPAD 33
f4dd75d9 44#define SAVEt_GENERIC_PVREF 34
c3564e5c 45#define SAVEt_PADSV 35
26d9b02f 46#define SAVEt_MORTALIZESV 36
05ec9bb3 47#define SAVEt_SHARED_PVREF 37
4f4e7967 48#define SAVEt_BOOL 38
79072805 49
b03c0a3a 50#ifndef SCOPE_SAVES_SIGNAL_MASK
1b266415 51#define SCOPE_SAVES_SIGNAL_MASK 0
b03c0a3a
NIS
52#endif
53
3280af22
NIS
54#define SSCHECK(need) if (PL_savestack_ix + need > PL_savestack_max) savestack_grow()
55#define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
56#define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
4f4e7967 57#define SSPUSHBOOL(p) (PL_savestack[PL_savestack_ix++].any_bool = (p))
3280af22
NIS
58#define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
59#define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
60#define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
c76ac1ee 61#define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p))
3280af22
NIS
62#define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
63#define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
4f4e7967 64#define SSPOPBOOL (PL_savestack[--PL_savestack_ix].any_bool)
3280af22
NIS
65#define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
66#define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
67#define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
c76ac1ee 68#define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr)
8990e307 69
954c1994 70/*
ccfc67b7
JH
71=head1 Callback Functions
72
954c1994
GS
73=for apidoc Ams||SAVETMPS
74Opening bracket for temporaries on a callback. See C<FREETMPS> and
75L<perlcall>.
76
77=for apidoc Ams||FREETMPS
78Closing bracket for temporaries on a callback. See C<SAVETMPS> and
79L<perlcall>.
80
81=for apidoc Ams||ENTER
82Opening bracket on a callback. See C<LEAVE> and L<perlcall>.
83
84=for apidoc Ams||LEAVE
85Closing bracket on a callback. See C<ENTER> and L<perlcall>.
86
87=cut
88*/
89
3280af22
NIS
90#define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix
91#define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
a0d0e21e 92
f46d017c
GS
93#ifdef DEBUGGING
94#define ENTER \
95 STMT_START { \
96 push_scope(); \
cea2e8a9 97 DEBUG_l(WITH_THR(Perl_deb(aTHX_ "ENTER scope %ld at %s:%d\n", \
3280af22 98 PL_scopestack_ix, __FILE__, __LINE__))); \
f46d017c
GS
99 } STMT_END
100#define LEAVE \
101 STMT_START { \
cea2e8a9 102 DEBUG_l(WITH_THR(Perl_deb(aTHX_ "LEAVE scope %ld at %s:%d\n", \
3280af22 103 PL_scopestack_ix, __FILE__, __LINE__))); \
f46d017c
GS
104 pop_scope(); \
105 } STMT_END
106#else
a0d0e21e
LW
107#define ENTER push_scope()
108#define LEAVE pop_scope()
f46d017c 109#endif
3280af22 110#define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old)
a0d0e21e 111
55497cff 112/*
b9d12d37 113 * Not using SOFT_CAST on SAVESPTR, SAVEGENERICSV and SAVEFREESV
55497cff 114 * because these are used for several kinds of pointer values
115 */
e8347627 116#define SAVEI8(i) save_I8(SOFT_CAST(I8*)&(i))
4fdae800 117#define SAVEI16(i) save_I16(SOFT_CAST(I16*)&(i))
118#define SAVEI32(i) save_I32(SOFT_CAST(I32*)&(i))
119#define SAVEINT(i) save_int(SOFT_CAST(int*)&(i))
120#define SAVEIV(i) save_iv(SOFT_CAST(IV*)&(i))
121#define SAVELONG(l) save_long(SOFT_CAST(long*)&(l))
4f4e7967 122#define SAVEBOOL(b) save_bool(SOFT_CAST(bool*)&(b))
55497cff 123#define SAVESPTR(s) save_sptr((SV**)&(s))
124#define SAVEPPTR(s) save_pptr(SOFT_CAST(char**)&(s))
57b2e452 125#define SAVEVPTR(s) save_vptr((void*)&(s))
c3564e5c 126#define SAVEPADSV(s) save_padsv(s)
55497cff 127#define SAVEFREESV(s) save_freesv((SV*)(s))
26d9b02f 128#define SAVEMORTALIZESV(s) save_mortalizesv((SV*)(s))
55497cff 129#define SAVEFREEOP(o) save_freeop(SOFT_CAST(OP*)(o))
130#define SAVEFREEPV(p) save_freepv(SOFT_CAST(char*)(p))
131#define SAVECLEARSV(sv) save_clearsv(SOFT_CAST(SV**)&(sv))
b9d12d37 132#define SAVEGENERICSV(s) save_generic_svref((SV**)&(s))
f4dd75d9 133#define SAVEGENERICPV(s) save_generic_pvref((char**)&(s))
05ec9bb3 134#define SAVESHAREDPV(s) save_shared_pvref((char**)&(s))
55497cff 135#define SAVEDELETE(h,k,l) \
136 save_delete(SOFT_CAST(HV*)(h), SOFT_CAST(char*)(k), (I32)(l))
137#define SAVEDESTRUCTOR(f,p) \
c76ac1ee
GS
138 save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), SOFT_CAST(void*)(p))
139
140#define SAVEDESTRUCTOR_X(f,p) \
141 save_destructor_x((DESTRUCTORFUNC_t)(f), SOFT_CAST(void*)(p))
25eaa213
GS
142
143#define SAVESTACK_POS() \
144 STMT_START { \
145 SSCHECK(2); \
3280af22 146 SSPUSHINT(PL_stack_sp - PL_stack_base); \
25eaa213
GS
147 SSPUSHINT(SAVEt_STACK_POS); \
148 } STMT_END
149
462e5cf6 150#define SAVEOP() save_op()
25eaa213
GS
151
152#define SAVEHINTS() \
153 STMT_START { \
3280af22 154 if (PL_hints & HINT_LOCALIZE_HH) \
25eaa213
GS
155 save_hints(); \
156 else { \
157 SSCHECK(2); \
3280af22 158 SSPUSHINT(PL_hints); \
25eaa213
GS
159 SSPUSHINT(SAVEt_HINTS); \
160 } \
161 } STMT_END
354992b1
GS
162
163#define SAVECOMPPAD() \
164 STMT_START { \
165 if (PL_comppad && PL_curpad == AvARRAY(PL_comppad)) { \
166 SSCHECK(2); \
167 SSPUSHPTR((SV*)PL_comppad); \
168 SSPUSHINT(SAVEt_COMPPAD); \
169 } \
170 else { \
171 SAVEVPTR(PL_curpad); \
172 SAVESPTR(PL_comppad); \
173 } \
174 } STMT_END
a9332b4a 175
57843af0 176#ifdef USE_ITHREADS
f4dd75d9 177# define SAVECOPSTASH(c) SAVEPPTR(CopSTASHPV(c))
05ec9bb3 178# define SAVECOPSTASH_FREE(c) SAVESHAREDPV(CopSTASHPV(c))
f4dd75d9 179# define SAVECOPFILE(c) SAVEPPTR(CopFILE(c))
05ec9bb3 180# define SAVECOPFILE_FREE(c) SAVESHAREDPV(CopFILE(c))
57843af0 181#else
f4dd75d9
GS
182# define SAVECOPSTASH(c) SAVESPTR(CopSTASH(c))
183# define SAVECOPSTASH_FREE(c) SAVECOPSTASH(c) /* XXX not refcounted */
184# define SAVECOPFILE(c) SAVESPTR(CopFILEGV(c))
185# define SAVECOPFILE_FREE(c) SAVEGENERICSV(CopFILEGV(c))
57843af0
GS
186#endif
187
f4dd75d9 188#define SAVECOPLINE(c) SAVEI16(CopLINE(c))
57843af0 189
455ece5e
AD
190/* SSNEW() temporarily allocates a specified number of bytes of data on the
191 * savestack. It returns an integer index into the savestack, because a
192 * pointer would get broken if the savestack is moved on reallocation.
193 * SSNEWa() works like SSNEW(), but also aligns the data to the specified
194 * number of bytes. MEM_ALIGNBYTES is perhaps the most useful. The
195 * alignment will be preserved therough savestack reallocation *only* if
196 * realloc returns data aligned to a size divisible by `align'!
197 *
198 * SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
199 */
200
f2b2c1a7 201#define SSNEW(size) Perl_save_alloc(aTHX_ (size), 0)
02db2b7b 202#define SSNEWt(n,t) SSNEW((n)*sizeof(t))
f2b2c1a7 203#define SSNEWa(size,align) Perl_save_alloc(aTHX_ (size), \
455ece5e 204 (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
02db2b7b 205#define SSNEWat(n,t,align) SSNEWa((n)*sizeof(t), align)
455ece5e 206
02db2b7b
IZ
207#define SSPTR(off,type) ((type) ((char*)PL_savestack + off))
208#define SSPTRt(off,type) ((type*) ((char*)PL_savestack + off))
455ece5e 209
54310121 210/* A jmpenv packages the state required to perform a proper non-local jump.
211 * Note that there is a start_env initialized when perl starts, and top_env
212 * points to this initially, so top_env should always be non-null.
213 *
214 * Existence of a non-null top_env->je_prev implies it is valid to call
6224f72b
GS
215 * longjmp() at that runlevel (we make sure start_env.je_prev is always
216 * null to ensure this).
54310121 217 *
218 * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
219 * establish a local jmpenv to handle exception traps. Care must be taken
220 * to restore the previous value of je_mustcatch before exiting the
221 * stack frame iff JMPENV_PUSH was not called in that stack frame.
6224f72b 222 * GSAR 97-03-27
54310121 223 */
224
225struct jmpenv {
226 struct jmpenv * je_prev;
312caa8e
CS
227 Sigjmp_buf je_buf; /* only for use if !je_throw */
228 int je_ret; /* last exception thrown */
229 bool je_mustcatch; /* need to call longjmp()? */
14dd3ad8 230#ifdef PERL_FLEXIBLE_EXCEPTIONS
312caa8e 231 void (*je_throw)(int v); /* last for bincompat */
db36c5a1 232 bool je_noset; /* no need for setjmp() */
14dd3ad8 233#endif
1163b5c4 234};
1163b5c4 235
6224f72b 236typedef struct jmpenv JMPENV;
1163b5c4 237
14dd3ad8
GS
238#ifdef OP_IN_REGISTER
239#define OP_REG_TO_MEM PL_opsave = op
240#define OP_MEM_TO_REG op = PL_opsave
241#else
242#define OP_REG_TO_MEM NOOP
243#define OP_MEM_TO_REG NOOP
244#endif
312caa8e
CS
245
246/*
247 * How to build the first jmpenv.
248 *
249 * top_env needs to be non-zero. It points to an area
250 * in which longjmp() stuff is stored, as C callstack
251 * info there at least is thread specific this has to
252 * be per-thread. Otherwise a 'die' in a thread gives
253 * that thread the C stack of last thread to do an eval {}!
254 */
255
256#define JMPENV_BOOTSTRAP \
257 STMT_START { \
14dd3ad8 258 Zero(&PL_start_env, 1, JMPENV); \
312caa8e
CS
259 PL_start_env.je_ret = -1; \
260 PL_start_env.je_mustcatch = TRUE; \
261 PL_top_env = &PL_start_env; \
262 } STMT_END
263
14dd3ad8 264#ifdef PERL_FLEXIBLE_EXCEPTIONS
462e5cf6 265
312caa8e
CS
266/*
267 * These exception-handling macros are split up to
268 * ease integration with C++ exceptions.
269 *
270 * To use C++ try+catch to catch Perl exceptions, an extension author
271 * needs to first write an extern "C" function to throw an appropriate
272 * exception object; typically it will be or contain an integer,
273 * because Perl's internals use integers to track exception types:
274 * extern "C" { static void thrower(int i) { throw i; } }
275 *
276 * Then (as shown below) the author needs to use, not the simple
277 * JMPENV_PUSH, but several of its constitutent macros, to arrange for
278 * the Perl internals to call thrower() rather than longjmp() to
279 * report exceptions:
280 *
281 * dJMPENV;
282 * JMPENV_PUSH_INIT(thrower);
283 * try {
284 * ... stuff that may throw exceptions ...
285 * }
286 * catch (int why) { // or whatever matches thrower()
287 * JMPENV_POST_CATCH;
288 * EXCEPT_SET(why);
289 * switch (why) {
290 * ... // handle various Perl exception codes
291 * }
292 * }
293 * JMPENV_POP; // don't forget this!
294 */
295
14dd3ad8
GS
296/*
297 * Function that catches/throws, and its callback for the
298 * body of protected processing.
299 */
300typedef void *(CPERLscope(*protect_body_t)) (pTHX_ va_list);
301typedef void *(CPERLscope(*protect_proc_t)) (pTHX_ volatile JMPENV *pcur_env,
302 int *, protect_body_t, ...);
303
db36c5a1
GS
304#define dJMPENV JMPENV cur_env; \
305 volatile JMPENV *pcur_env = ((cur_env.je_noset = 0),&cur_env)
312caa8e 306
db36c5a1 307#define JMPENV_PUSH_INIT_ENV(ce,THROWFUNC) \
6224f72b 308 STMT_START { \
db36c5a1
GS
309 (ce).je_throw = (THROWFUNC); \
310 (ce).je_ret = -1; \
311 (ce).je_mustcatch = FALSE; \
312 (ce).je_prev = PL_top_env; \
313 PL_top_env = &(ce); \
6224f72b 314 OP_REG_TO_MEM; \
312caa8e 315 } STMT_END
1d651c14 316
f2b2c1a7 317#define JMPENV_PUSH_INIT(THROWFUNC) JMPENV_PUSH_INIT_ENV(*(JMPENV*)pcur_env,THROWFUNC)
1d651c14 318
db36c5a1 319#define JMPENV_POST_CATCH_ENV(ce) \
312caa8e 320 STMT_START { \
6224f72b 321 OP_MEM_TO_REG; \
db36c5a1 322 PL_top_env = &(ce); \
6224f72b 323 } STMT_END
312caa8e 324
db36c5a1 325#define JMPENV_POST_CATCH JMPENV_POST_CATCH_ENV(*(JMPENV*)pcur_env)
1d651c14 326
db36c5a1
GS
327#define JMPENV_PUSH_ENV(ce,v) \
328 STMT_START { \
329 if (!(ce).je_noset) { \
14dd3ad8
GS
330 DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \
331 ce, PL_top_env)); \
db36c5a1 332 JMPENV_PUSH_INIT_ENV(ce,NULL); \
b03c0a3a 333 EXCEPT_SET_ENV(ce,PerlProc_setjmp((ce).je_buf, SCOPE_SAVES_SIGNAL_MASK));\
db36c5a1
GS
334 (ce).je_noset = 1; \
335 } \
336 else \
337 EXCEPT_SET_ENV(ce,0); \
338 JMPENV_POST_CATCH_ENV(ce); \
339 (v) = EXCEPT_GET_ENV(ce); \
312caa8e
CS
340 } STMT_END
341
f2b2c1a7 342#define JMPENV_PUSH(v) JMPENV_PUSH_ENV(*(JMPENV*)pcur_env,v)
1d651c14 343
db36c5a1 344#define JMPENV_POP_ENV(ce) \
14dd3ad8
GS
345 STMT_START { \
346 if (PL_top_env == &(ce)) \
347 PL_top_env = (ce).je_prev; \
348 } STMT_END
312caa8e 349
f2b2c1a7 350#define JMPENV_POP JMPENV_POP_ENV(*(JMPENV*)pcur_env)
1d651c14 351
22921e25
CS
352#define JMPENV_JUMP(v) \
353 STMT_START { \
462e5cf6 354 OP_REG_TO_MEM; \
312caa8e
CS
355 if (PL_top_env->je_prev) { \
356 if (PL_top_env->je_throw) \
357 PL_top_env->je_throw(v); \
358 else \
359 PerlProc_longjmp(PL_top_env->je_buf, (v)); \
360 } \
6224f72b 361 if ((v) == 2) \
312caa8e 362 PerlProc_exit(STATUS_NATIVE_EXPORT); \
bf49b057 363 PerlIO_printf(Perl_error_log, "panic: top_env\n"); \
312caa8e 364 PerlProc_exit(1); \
22921e25 365 } STMT_END
312caa8e 366
db36c5a1
GS
367#define EXCEPT_GET_ENV(ce) ((ce).je_ret)
368#define EXCEPT_GET EXCEPT_GET_ENV(*(JMPENV*)pcur_env)
369#define EXCEPT_SET_ENV(ce,v) ((ce).je_ret = (v))
370#define EXCEPT_SET(v) EXCEPT_SET_ENV(*(JMPENV*)pcur_env,v)
312caa8e 371
14dd3ad8
GS
372#else /* !PERL_FLEXIBLE_EXCEPTIONS */
373
374#define dJMPENV JMPENV cur_env
375
376#define JMPENV_PUSH(v) \
377 STMT_START { \
378 DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \
379 &cur_env, PL_top_env)); \
380 cur_env.je_prev = PL_top_env; \
381 OP_REG_TO_MEM; \
b03c0a3a 382 cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK); \
14dd3ad8
GS
383 OP_MEM_TO_REG; \
384 PL_top_env = &cur_env; \
385 cur_env.je_mustcatch = FALSE; \
386 (v) = cur_env.je_ret; \
387 } STMT_END
388
389#define JMPENV_POP \
390 STMT_START { PL_top_env = cur_env.je_prev; } STMT_END
391
392#define JMPENV_JUMP(v) \
393 STMT_START { \
394 OP_REG_TO_MEM; \
395 if (PL_top_env->je_prev) \
396 PerlProc_longjmp(PL_top_env->je_buf, (v)); \
397 if ((v) == 2) \
398 PerlProc_exit(STATUS_NATIVE_EXPORT); \
399 PerlIO_printf(PerlIO_stderr(), "panic: top_env\n"); \
400 PerlProc_exit(1); \
401 } STMT_END
402
403#endif /* PERL_FLEXIBLE_EXCEPTIONS */
404
db36c5a1
GS
405#define CATCH_GET (PL_top_env->je_mustcatch)
406#define CATCH_SET(v) (PL_top_env->je_mustcatch = (v))