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1/* scope.h
2 *
4bb101f2
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3 * Copyright (C) 1993, 1994, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, by Larry Wall and others
d6376244
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5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
8 *
9 */
10
b9d12d37
GS
11#define SAVEt_ITEM 0
12#define SAVEt_SV 1
13#define SAVEt_AV 2
14#define SAVEt_HV 3
15#define SAVEt_INT 4
16#define SAVEt_LONG 5
17#define SAVEt_I32 6
18#define SAVEt_IV 7
19#define SAVEt_SPTR 8
20#define SAVEt_APTR 9
21#define SAVEt_HPTR 10
22#define SAVEt_PPTR 11
23#define SAVEt_NSTAB 12
24#define SAVEt_SVREF 13
25#define SAVEt_GP 14
26#define SAVEt_FREESV 15
27#define SAVEt_FREEOP 16
28#define SAVEt_FREEPV 17
29#define SAVEt_CLEARSV 18
30#define SAVEt_DELETE 19
31#define SAVEt_DESTRUCTOR 20
32#define SAVEt_REGCONTEXT 21
33#define SAVEt_STACK_POS 22
34#define SAVEt_I16 23
35#define SAVEt_AELEM 24
36#define SAVEt_HELEM 25
37#define SAVEt_OP 26
38#define SAVEt_HINTS 27
39#define SAVEt_ALLOC 28
40#define SAVEt_GENERIC_SVREF 29
c76ac1ee 41#define SAVEt_DESTRUCTOR_X 30
7766f137 42#define SAVEt_VPTR 31
e8347627 43#define SAVEt_I8 32
354992b1 44#define SAVEt_COMPPAD 33
f4dd75d9 45#define SAVEt_GENERIC_PVREF 34
c3564e5c 46#define SAVEt_PADSV 35
26d9b02f 47#define SAVEt_MORTALIZESV 36
05ec9bb3 48#define SAVEt_SHARED_PVREF 37
9febdf04 49#define SAVEt_BOOL 38
79072805 50
b03c0a3a 51#ifndef SCOPE_SAVES_SIGNAL_MASK
1b266415 52#define SCOPE_SAVES_SIGNAL_MASK 0
b03c0a3a
NIS
53#endif
54
4b3c1a47
AE
55#define SSCHECK(need) if (PL_savestack_ix + (need) > PL_savestack_max) savestack_grow()
56#define SSGROW(need) if (PL_savestack_ix + (need) > PL_savestack_max) savestack_grow_cnt(need)
3280af22
NIS
57#define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
58#define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
9febdf04 59#define SSPUSHBOOL(p) (PL_savestack[PL_savestack_ix++].any_bool = (p))
3280af22
NIS
60#define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
61#define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
62#define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
c76ac1ee 63#define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p))
3280af22
NIS
64#define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
65#define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
9febdf04 66#define SSPOPBOOL (PL_savestack[--PL_savestack_ix].any_bool)
3280af22
NIS
67#define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
68#define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
69#define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
c76ac1ee 70#define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr)
8990e307 71
954c1994 72/*
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73=head1 Callback Functions
74
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75=for apidoc Ams||SAVETMPS
76Opening bracket for temporaries on a callback. See C<FREETMPS> and
77L<perlcall>.
78
79=for apidoc Ams||FREETMPS
80Closing bracket for temporaries on a callback. See C<SAVETMPS> and
81L<perlcall>.
82
83=for apidoc Ams||ENTER
84Opening bracket on a callback. See C<LEAVE> and L<perlcall>.
85
86=for apidoc Ams||LEAVE
87Closing bracket on a callback. See C<ENTER> and L<perlcall>.
88
89=cut
90*/
91
3280af22
NIS
92#define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix
93#define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
a0d0e21e 94
f46d017c
GS
95#ifdef DEBUGGING
96#define ENTER \
97 STMT_START { \
98 push_scope(); \
b4ab917c 99 DEBUG_SCOPE("ENTER") \
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100 } STMT_END
101#define LEAVE \
102 STMT_START { \
b4ab917c 103 DEBUG_SCOPE("LEAVE") \
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104 pop_scope(); \
105 } STMT_END
106#else
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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
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PP
114 * because these are used for several kinds of pointer values
115 */
e8347627 116#define SAVEI8(i) save_I8(SOFT_CAST(I8*)&(i))
4fdae800
PP
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))
9febdf04 122#define SAVEBOOL(b) save_bool(SOFT_CAST(bool*)&(b))
55497cff
PP
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
PP
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
PP
135#define SAVEDELETE(h,k,l) \
136 save_delete(SOFT_CAST(HV*)(h), SOFT_CAST(char*)(k), (I32)(l))
137#define SAVEDESTRUCTOR(f,p) \
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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) \
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155 save_hints(); \
156 else { \
157 SSCHECK(2); \
3280af22 158 SSPUSHINT(PL_hints); \
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159 SSPUSHINT(SAVEt_HINTS); \
160 } \
161 } STMT_END
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162
163#define SAVECOMPPAD() \
164 STMT_START { \
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DM
165 SSCHECK(2); \
166 SSPUSHPTR((SV*)PL_comppad); \
167 SSPUSHINT(SAVEt_COMPPAD); \
354992b1 168 } STMT_END
a9332b4a 169
57843af0 170#ifdef USE_ITHREADS
f4dd75d9 171# define SAVECOPSTASH(c) SAVEPPTR(CopSTASHPV(c))
05ec9bb3 172# define SAVECOPSTASH_FREE(c) SAVESHAREDPV(CopSTASHPV(c))
f4dd75d9 173# define SAVECOPFILE(c) SAVEPPTR(CopFILE(c))
05ec9bb3 174# define SAVECOPFILE_FREE(c) SAVESHAREDPV(CopFILE(c))
57843af0 175#else
f4dd75d9
GS
176# define SAVECOPSTASH(c) SAVESPTR(CopSTASH(c))
177# define SAVECOPSTASH_FREE(c) SAVECOPSTASH(c) /* XXX not refcounted */
178# define SAVECOPFILE(c) SAVESPTR(CopFILEGV(c))
179# define SAVECOPFILE_FREE(c) SAVEGENERICSV(CopFILEGV(c))
57843af0
GS
180#endif
181
dea28490 182#define SAVECOPLINE(c) SAVEI32(CopLINE(c))
57843af0 183
455ece5e
AD
184/* SSNEW() temporarily allocates a specified number of bytes of data on the
185 * savestack. It returns an integer index into the savestack, because a
186 * pointer would get broken if the savestack is moved on reallocation.
187 * SSNEWa() works like SSNEW(), but also aligns the data to the specified
188 * number of bytes. MEM_ALIGNBYTES is perhaps the most useful. The
189 * alignment will be preserved therough savestack reallocation *only* if
190 * realloc returns data aligned to a size divisible by `align'!
191 *
192 * SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
193 */
194
f2b2c1a7 195#define SSNEW(size) Perl_save_alloc(aTHX_ (size), 0)
02db2b7b 196#define SSNEWt(n,t) SSNEW((n)*sizeof(t))
f2b2c1a7 197#define SSNEWa(size,align) Perl_save_alloc(aTHX_ (size), \
455ece5e 198 (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
02db2b7b 199#define SSNEWat(n,t,align) SSNEWa((n)*sizeof(t), align)
455ece5e 200
02db2b7b
IZ
201#define SSPTR(off,type) ((type) ((char*)PL_savestack + off))
202#define SSPTRt(off,type) ((type*) ((char*)PL_savestack + off))
455ece5e 203
54310121
PP
204/* A jmpenv packages the state required to perform a proper non-local jump.
205 * Note that there is a start_env initialized when perl starts, and top_env
206 * points to this initially, so top_env should always be non-null.
207 *
208 * Existence of a non-null top_env->je_prev implies it is valid to call
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GS
209 * longjmp() at that runlevel (we make sure start_env.je_prev is always
210 * null to ensure this).
54310121
PP
211 *
212 * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
213 * establish a local jmpenv to handle exception traps. Care must be taken
214 * to restore the previous value of je_mustcatch before exiting the
215 * stack frame iff JMPENV_PUSH was not called in that stack frame.
6224f72b 216 * GSAR 97-03-27
54310121
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217 */
218
219struct jmpenv {
220 struct jmpenv * je_prev;
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221 Sigjmp_buf je_buf; /* only for use if !je_throw */
222 int je_ret; /* last exception thrown */
223 bool je_mustcatch; /* need to call longjmp()? */
14dd3ad8 224#ifdef PERL_FLEXIBLE_EXCEPTIONS
312caa8e 225 void (*je_throw)(int v); /* last for bincompat */
db36c5a1 226 bool je_noset; /* no need for setjmp() */
14dd3ad8 227#endif
1163b5c4 228};
1163b5c4 229
6224f72b 230typedef struct jmpenv JMPENV;
1163b5c4 231
14dd3ad8
GS
232#ifdef OP_IN_REGISTER
233#define OP_REG_TO_MEM PL_opsave = op
234#define OP_MEM_TO_REG op = PL_opsave
235#else
236#define OP_REG_TO_MEM NOOP
237#define OP_MEM_TO_REG NOOP
238#endif
312caa8e
CS
239
240/*
241 * How to build the first jmpenv.
242 *
243 * top_env needs to be non-zero. It points to an area
244 * in which longjmp() stuff is stored, as C callstack
245 * info there at least is thread specific this has to
246 * be per-thread. Otherwise a 'die' in a thread gives
247 * that thread the C stack of last thread to do an eval {}!
248 */
249
250#define JMPENV_BOOTSTRAP \
251 STMT_START { \
14dd3ad8 252 Zero(&PL_start_env, 1, JMPENV); \
312caa8e
CS
253 PL_start_env.je_ret = -1; \
254 PL_start_env.je_mustcatch = TRUE; \
255 PL_top_env = &PL_start_env; \
256 } STMT_END
257
14dd3ad8 258#ifdef PERL_FLEXIBLE_EXCEPTIONS
462e5cf6 259
312caa8e
CS
260/*
261 * These exception-handling macros are split up to
262 * ease integration with C++ exceptions.
263 *
264 * To use C++ try+catch to catch Perl exceptions, an extension author
265 * needs to first write an extern "C" function to throw an appropriate
266 * exception object; typically it will be or contain an integer,
267 * because Perl's internals use integers to track exception types:
268 * extern "C" { static void thrower(int i) { throw i; } }
269 *
270 * Then (as shown below) the author needs to use, not the simple
271 * JMPENV_PUSH, but several of its constitutent macros, to arrange for
272 * the Perl internals to call thrower() rather than longjmp() to
273 * report exceptions:
274 *
275 * dJMPENV;
276 * JMPENV_PUSH_INIT(thrower);
277 * try {
278 * ... stuff that may throw exceptions ...
279 * }
280 * catch (int why) { // or whatever matches thrower()
281 * JMPENV_POST_CATCH;
282 * EXCEPT_SET(why);
283 * switch (why) {
284 * ... // handle various Perl exception codes
285 * }
286 * }
287 * JMPENV_POP; // don't forget this!
288 */
289
14dd3ad8
GS
290/*
291 * Function that catches/throws, and its callback for the
292 * body of protected processing.
293 */
294typedef void *(CPERLscope(*protect_body_t)) (pTHX_ va_list);
295typedef void *(CPERLscope(*protect_proc_t)) (pTHX_ volatile JMPENV *pcur_env,
296 int *, protect_body_t, ...);
297
db36c5a1
GS
298#define dJMPENV JMPENV cur_env; \
299 volatile JMPENV *pcur_env = ((cur_env.je_noset = 0),&cur_env)
312caa8e 300
db36c5a1 301#define JMPENV_PUSH_INIT_ENV(ce,THROWFUNC) \
6224f72b 302 STMT_START { \
db36c5a1
GS
303 (ce).je_throw = (THROWFUNC); \
304 (ce).je_ret = -1; \
305 (ce).je_mustcatch = FALSE; \
306 (ce).je_prev = PL_top_env; \
307 PL_top_env = &(ce); \
6224f72b 308 OP_REG_TO_MEM; \
312caa8e 309 } STMT_END
1d651c14 310
f2b2c1a7 311#define JMPENV_PUSH_INIT(THROWFUNC) JMPENV_PUSH_INIT_ENV(*(JMPENV*)pcur_env,THROWFUNC)
1d651c14 312
db36c5a1 313#define JMPENV_POST_CATCH_ENV(ce) \
312caa8e 314 STMT_START { \
6224f72b 315 OP_MEM_TO_REG; \
db36c5a1 316 PL_top_env = &(ce); \
6224f72b 317 } STMT_END
312caa8e 318
db36c5a1 319#define JMPENV_POST_CATCH JMPENV_POST_CATCH_ENV(*(JMPENV*)pcur_env)
1d651c14 320
db36c5a1
GS
321#define JMPENV_PUSH_ENV(ce,v) \
322 STMT_START { \
323 if (!(ce).je_noset) { \
14dd3ad8
GS
324 DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \
325 ce, PL_top_env)); \
db36c5a1 326 JMPENV_PUSH_INIT_ENV(ce,NULL); \
b03c0a3a 327 EXCEPT_SET_ENV(ce,PerlProc_setjmp((ce).je_buf, SCOPE_SAVES_SIGNAL_MASK));\
db36c5a1
GS
328 (ce).je_noset = 1; \
329 } \
330 else \
331 EXCEPT_SET_ENV(ce,0); \
332 JMPENV_POST_CATCH_ENV(ce); \
333 (v) = EXCEPT_GET_ENV(ce); \
312caa8e
CS
334 } STMT_END
335
f2b2c1a7 336#define JMPENV_PUSH(v) JMPENV_PUSH_ENV(*(JMPENV*)pcur_env,v)
1d651c14 337
db36c5a1 338#define JMPENV_POP_ENV(ce) \
14dd3ad8
GS
339 STMT_START { \
340 if (PL_top_env == &(ce)) \
341 PL_top_env = (ce).je_prev; \
342 } STMT_END
312caa8e 343
f2b2c1a7 344#define JMPENV_POP JMPENV_POP_ENV(*(JMPENV*)pcur_env)
1d651c14 345
22921e25
CS
346#define JMPENV_JUMP(v) \
347 STMT_START { \
462e5cf6 348 OP_REG_TO_MEM; \
312caa8e
CS
349 if (PL_top_env->je_prev) { \
350 if (PL_top_env->je_throw) \
351 PL_top_env->je_throw(v); \
352 else \
353 PerlProc_longjmp(PL_top_env->je_buf, (v)); \
354 } \
6224f72b 355 if ((v) == 2) \
312caa8e 356 PerlProc_exit(STATUS_NATIVE_EXPORT); \
bf49b057 357 PerlIO_printf(Perl_error_log, "panic: top_env\n"); \
312caa8e 358 PerlProc_exit(1); \
22921e25 359 } STMT_END
312caa8e 360
db36c5a1
GS
361#define EXCEPT_GET_ENV(ce) ((ce).je_ret)
362#define EXCEPT_GET EXCEPT_GET_ENV(*(JMPENV*)pcur_env)
363#define EXCEPT_SET_ENV(ce,v) ((ce).je_ret = (v))
364#define EXCEPT_SET(v) EXCEPT_SET_ENV(*(JMPENV*)pcur_env,v)
312caa8e 365
14dd3ad8
GS
366#else /* !PERL_FLEXIBLE_EXCEPTIONS */
367
368#define dJMPENV JMPENV cur_env
369
370#define JMPENV_PUSH(v) \
371 STMT_START { \
372 DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \
373 &cur_env, PL_top_env)); \
374 cur_env.je_prev = PL_top_env; \
375 OP_REG_TO_MEM; \
b03c0a3a 376 cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK); \
14dd3ad8
GS
377 OP_MEM_TO_REG; \
378 PL_top_env = &cur_env; \
379 cur_env.je_mustcatch = FALSE; \
380 (v) = cur_env.je_ret; \
381 } STMT_END
382
383#define JMPENV_POP \
384 STMT_START { PL_top_env = cur_env.je_prev; } STMT_END
385
386#define JMPENV_JUMP(v) \
387 STMT_START { \
388 OP_REG_TO_MEM; \
389 if (PL_top_env->je_prev) \
390 PerlProc_longjmp(PL_top_env->je_buf, (v)); \
391 if ((v) == 2) \
392 PerlProc_exit(STATUS_NATIVE_EXPORT); \
393 PerlIO_printf(PerlIO_stderr(), "panic: top_env\n"); \
394 PerlProc_exit(1); \
395 } STMT_END
396
397#endif /* PERL_FLEXIBLE_EXCEPTIONS */
398
db36c5a1
GS
399#define CATCH_GET (PL_top_env->je_mustcatch)
400#define CATCH_SET(v) (PL_top_env->je_mustcatch = (v))