| 1 | /* scope.h |
| 2 | * |
| 3 | * Copyright (C) 1993, 1994, 1996, 1997, 1998, 1999, |
| 4 | * 2000, 2001, 2002, 2004, 2005 by Larry Wall and others |
| 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 | |
| 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 |
| 41 | #define SAVEt_DESTRUCTOR_X 30 |
| 42 | #define SAVEt_VPTR 31 |
| 43 | #define SAVEt_I8 32 |
| 44 | #define SAVEt_COMPPAD 33 |
| 45 | #define SAVEt_GENERIC_PVREF 34 |
| 46 | #define SAVEt_PADSV 35 |
| 47 | #define SAVEt_MORTALIZESV 36 |
| 48 | #define SAVEt_SHARED_PVREF 37 |
| 49 | #define SAVEt_BOOL 38 |
| 50 | #define SAVEt_SAVESWITCHSTACK 40 |
| 51 | |
| 52 | #ifndef SCOPE_SAVES_SIGNAL_MASK |
| 53 | #define SCOPE_SAVES_SIGNAL_MASK 0 |
| 54 | #endif |
| 55 | |
| 56 | #define SSCHECK(need) if (PL_savestack_ix + (need) > PL_savestack_max) savestack_grow() |
| 57 | #define SSGROW(need) if (PL_savestack_ix + (need) > PL_savestack_max) savestack_grow_cnt(need) |
| 58 | #define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i)) |
| 59 | #define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i)) |
| 60 | #define SSPUSHBOOL(p) (PL_savestack[PL_savestack_ix++].any_bool = (p)) |
| 61 | #define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i)) |
| 62 | #define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p)) |
| 63 | #define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p)) |
| 64 | #define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p)) |
| 65 | #define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32) |
| 66 | #define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long) |
| 67 | #define SSPOPBOOL (PL_savestack[--PL_savestack_ix].any_bool) |
| 68 | #define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv) |
| 69 | #define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr) |
| 70 | #define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr) |
| 71 | #define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr) |
| 72 | |
| 73 | /* |
| 74 | =head1 Callback Functions |
| 75 | |
| 76 | =for apidoc Ams||SAVETMPS |
| 77 | Opening bracket for temporaries on a callback. See C<FREETMPS> and |
| 78 | L<perlcall>. |
| 79 | |
| 80 | =for apidoc Ams||FREETMPS |
| 81 | Closing bracket for temporaries on a callback. See C<SAVETMPS> and |
| 82 | L<perlcall>. |
| 83 | |
| 84 | =for apidoc Ams||ENTER |
| 85 | Opening bracket on a callback. See C<LEAVE> and L<perlcall>. |
| 86 | |
| 87 | =for apidoc Ams||LEAVE |
| 88 | Closing bracket on a callback. See C<ENTER> and L<perlcall>. |
| 89 | |
| 90 | =cut |
| 91 | */ |
| 92 | |
| 93 | #define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix |
| 94 | #define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps() |
| 95 | |
| 96 | #ifdef DEBUGGING |
| 97 | #define ENTER \ |
| 98 | STMT_START { \ |
| 99 | push_scope(); \ |
| 100 | DEBUG_SCOPE("ENTER") \ |
| 101 | } STMT_END |
| 102 | #define LEAVE \ |
| 103 | STMT_START { \ |
| 104 | DEBUG_SCOPE("LEAVE") \ |
| 105 | pop_scope(); \ |
| 106 | } STMT_END |
| 107 | #else |
| 108 | #define ENTER push_scope() |
| 109 | #define LEAVE pop_scope() |
| 110 | #endif |
| 111 | #define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old) |
| 112 | |
| 113 | /* |
| 114 | * Not using SOFT_CAST on SAVESPTR, SAVEGENERICSV and SAVEFREESV |
| 115 | * because these are used for several kinds of pointer values |
| 116 | */ |
| 117 | #define SAVEI8(i) save_I8(SOFT_CAST(I8*)&(i)) |
| 118 | #define SAVEI16(i) save_I16(SOFT_CAST(I16*)&(i)) |
| 119 | #define SAVEI32(i) save_I32(SOFT_CAST(I32*)&(i)) |
| 120 | #define SAVEINT(i) save_int(SOFT_CAST(int*)&(i)) |
| 121 | #define SAVEIV(i) save_iv(SOFT_CAST(IV*)&(i)) |
| 122 | #define SAVELONG(l) save_long(SOFT_CAST(long*)&(l)) |
| 123 | #define SAVEBOOL(b) save_bool(SOFT_CAST(bool*)&(b)) |
| 124 | #define SAVESPTR(s) save_sptr((SV**)&(s)) |
| 125 | #define SAVEPPTR(s) save_pptr(SOFT_CAST(char**)&(s)) |
| 126 | #define SAVEVPTR(s) save_vptr((void*)&(s)) |
| 127 | #define SAVEPADSV(s) save_padsv(s) |
| 128 | #define SAVEFREESV(s) save_freesv((SV*)(s)) |
| 129 | #define SAVEMORTALIZESV(s) save_mortalizesv((SV*)(s)) |
| 130 | #define SAVEFREEOP(o) save_freeop(SOFT_CAST(OP*)(o)) |
| 131 | #define SAVEFREEPV(p) save_freepv(SOFT_CAST(char*)(p)) |
| 132 | #define SAVECLEARSV(sv) save_clearsv(SOFT_CAST(SV**)&(sv)) |
| 133 | #define SAVEGENERICSV(s) save_generic_svref((SV**)&(s)) |
| 134 | #define SAVEGENERICPV(s) save_generic_pvref((char**)&(s)) |
| 135 | #define SAVESHAREDPV(s) save_shared_pvref((char**)&(s)) |
| 136 | #define SAVEDELETE(h,k,l) \ |
| 137 | save_delete(SOFT_CAST(HV*)(h), SOFT_CAST(char*)(k), (I32)(l)) |
| 138 | #define SAVEDESTRUCTOR(f,p) \ |
| 139 | save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), SOFT_CAST(void*)(p)) |
| 140 | |
| 141 | #define SAVEDESTRUCTOR_X(f,p) \ |
| 142 | save_destructor_x((DESTRUCTORFUNC_t)(f), SOFT_CAST(void*)(p)) |
| 143 | |
| 144 | #define SAVESTACK_POS() \ |
| 145 | STMT_START { \ |
| 146 | SSCHECK(2); \ |
| 147 | SSPUSHINT(PL_stack_sp - PL_stack_base); \ |
| 148 | SSPUSHINT(SAVEt_STACK_POS); \ |
| 149 | } STMT_END |
| 150 | |
| 151 | #define SAVEOP() save_op() |
| 152 | |
| 153 | #define SAVEHINTS() \ |
| 154 | STMT_START { \ |
| 155 | SSCHECK(3); \ |
| 156 | if (PL_hints & HINT_LOCALIZE_HH) { \ |
| 157 | SSPUSHPTR(GvHV(PL_hintgv)); \ |
| 158 | GvHV(PL_hintgv) = newHVhv(GvHV(PL_hintgv)); \ |
| 159 | } \ |
| 160 | SSPUSHINT(PL_hints); \ |
| 161 | SSPUSHINT(SAVEt_HINTS); \ |
| 162 | } STMT_END |
| 163 | |
| 164 | #define SAVECOMPPAD() \ |
| 165 | STMT_START { \ |
| 166 | SSCHECK(2); \ |
| 167 | SSPUSHPTR((SV*)PL_comppad); \ |
| 168 | SSPUSHINT(SAVEt_COMPPAD); \ |
| 169 | } STMT_END |
| 170 | |
| 171 | #define SAVESWITCHSTACK(f,t) \ |
| 172 | STMT_START { \ |
| 173 | SSCHECK(3); \ |
| 174 | SSPUSHPTR((SV*)(f)); \ |
| 175 | SSPUSHPTR((SV*)(t)); \ |
| 176 | SSPUSHINT(SAVEt_SAVESWITCHSTACK); \ |
| 177 | SWITCHSTACK((f),(t)); \ |
| 178 | PL_curstackinfo->si_stack = (t); \ |
| 179 | } STMT_END |
| 180 | |
| 181 | #ifdef USE_ITHREADS |
| 182 | # define SAVECOPSTASH(c) SAVEPPTR(CopSTASHPV(c)) |
| 183 | # define SAVECOPSTASH_FREE(c) SAVESHAREDPV(CopSTASHPV(c)) |
| 184 | # define SAVECOPFILE(c) SAVEPPTR(CopFILE(c)) |
| 185 | # define SAVECOPFILE_FREE(c) SAVESHAREDPV(CopFILE(c)) |
| 186 | #else |
| 187 | # define SAVECOPSTASH(c) SAVESPTR(CopSTASH(c)) |
| 188 | # define SAVECOPSTASH_FREE(c) SAVECOPSTASH(c) /* XXX not refcounted */ |
| 189 | # define SAVECOPFILE(c) SAVESPTR(CopFILEGV(c)) |
| 190 | # define SAVECOPFILE_FREE(c) SAVEGENERICSV(CopFILEGV(c)) |
| 191 | #endif |
| 192 | |
| 193 | #define SAVECOPLINE(c) SAVEI32(CopLINE(c)) |
| 194 | |
| 195 | /* SSNEW() temporarily allocates a specified number of bytes of data on the |
| 196 | * savestack. It returns an integer index into the savestack, because a |
| 197 | * pointer would get broken if the savestack is moved on reallocation. |
| 198 | * SSNEWa() works like SSNEW(), but also aligns the data to the specified |
| 199 | * number of bytes. MEM_ALIGNBYTES is perhaps the most useful. The |
| 200 | * alignment will be preserved therough savestack reallocation *only* if |
| 201 | * realloc returns data aligned to a size divisible by "align"! |
| 202 | * |
| 203 | * SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer. |
| 204 | */ |
| 205 | |
| 206 | #define SSNEW(size) Perl_save_alloc(aTHX_ (size), 0) |
| 207 | #define SSNEWt(n,t) SSNEW((n)*sizeof(t)) |
| 208 | #define SSNEWa(size,align) Perl_save_alloc(aTHX_ (size), \ |
| 209 | (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align) |
| 210 | #define SSNEWat(n,t,align) SSNEWa((n)*sizeof(t), align) |
| 211 | |
| 212 | #define SSPTR(off,type) ((type) ((char*)PL_savestack + off)) |
| 213 | #define SSPTRt(off,type) ((type*) ((char*)PL_savestack + off)) |
| 214 | |
| 215 | /* A jmpenv packages the state required to perform a proper non-local jump. |
| 216 | * Note that there is a start_env initialized when perl starts, and top_env |
| 217 | * points to this initially, so top_env should always be non-null. |
| 218 | * |
| 219 | * Existence of a non-null top_env->je_prev implies it is valid to call |
| 220 | * longjmp() at that runlevel (we make sure start_env.je_prev is always |
| 221 | * null to ensure this). |
| 222 | * |
| 223 | * je_mustcatch, when set at any runlevel to TRUE, means eval ops must |
| 224 | * establish a local jmpenv to handle exception traps. Care must be taken |
| 225 | * to restore the previous value of je_mustcatch before exiting the |
| 226 | * stack frame iff JMPENV_PUSH was not called in that stack frame. |
| 227 | * GSAR 97-03-27 |
| 228 | */ |
| 229 | |
| 230 | struct jmpenv { |
| 231 | struct jmpenv * je_prev; |
| 232 | Sigjmp_buf je_buf; /* only for use if !je_throw */ |
| 233 | int je_ret; /* last exception thrown */ |
| 234 | bool je_mustcatch; /* need to call longjmp()? */ |
| 235 | #ifdef PERL_FLEXIBLE_EXCEPTIONS |
| 236 | void (*je_throw)(int v); /* last for bincompat */ |
| 237 | bool je_noset; /* no need for setjmp() */ |
| 238 | #endif |
| 239 | }; |
| 240 | |
| 241 | typedef struct jmpenv JMPENV; |
| 242 | |
| 243 | #ifdef OP_IN_REGISTER |
| 244 | #define OP_REG_TO_MEM PL_opsave = op |
| 245 | #define OP_MEM_TO_REG op = PL_opsave |
| 246 | #else |
| 247 | #define OP_REG_TO_MEM NOOP |
| 248 | #define OP_MEM_TO_REG NOOP |
| 249 | #endif |
| 250 | |
| 251 | /* |
| 252 | * How to build the first jmpenv. |
| 253 | * |
| 254 | * top_env needs to be non-zero. It points to an area |
| 255 | * in which longjmp() stuff is stored, as C callstack |
| 256 | * info there at least is thread specific this has to |
| 257 | * be per-thread. Otherwise a 'die' in a thread gives |
| 258 | * that thread the C stack of last thread to do an eval {}! |
| 259 | */ |
| 260 | |
| 261 | #define JMPENV_BOOTSTRAP \ |
| 262 | STMT_START { \ |
| 263 | Zero(&PL_start_env, 1, JMPENV); \ |
| 264 | PL_start_env.je_ret = -1; \ |
| 265 | PL_start_env.je_mustcatch = TRUE; \ |
| 266 | PL_top_env = &PL_start_env; \ |
| 267 | } STMT_END |
| 268 | |
| 269 | #ifdef PERL_FLEXIBLE_EXCEPTIONS |
| 270 | |
| 271 | /* |
| 272 | * These exception-handling macros are split up to |
| 273 | * ease integration with C++ exceptions. |
| 274 | * |
| 275 | * To use C++ try+catch to catch Perl exceptions, an extension author |
| 276 | * needs to first write an extern "C" function to throw an appropriate |
| 277 | * exception object; typically it will be or contain an integer, |
| 278 | * because Perl's internals use integers to track exception types: |
| 279 | * extern "C" { static void thrower(int i) { throw i; } } |
| 280 | * |
| 281 | * Then (as shown below) the author needs to use, not the simple |
| 282 | * JMPENV_PUSH, but several of its constitutent macros, to arrange for |
| 283 | * the Perl internals to call thrower() rather than longjmp() to |
| 284 | * report exceptions: |
| 285 | * |
| 286 | * dJMPENV; |
| 287 | * JMPENV_PUSH_INIT(thrower); |
| 288 | * try { |
| 289 | * ... stuff that may throw exceptions ... |
| 290 | * } |
| 291 | * catch (int why) { // or whatever matches thrower() |
| 292 | * JMPENV_POST_CATCH; |
| 293 | * EXCEPT_SET(why); |
| 294 | * switch (why) { |
| 295 | * ... // handle various Perl exception codes |
| 296 | * } |
| 297 | * } |
| 298 | * JMPENV_POP; // don't forget this! |
| 299 | */ |
| 300 | |
| 301 | /* |
| 302 | * Function that catches/throws, and its callback for the |
| 303 | * body of protected processing. |
| 304 | */ |
| 305 | typedef void *(CPERLscope(*protect_body_t)) (pTHX_ va_list); |
| 306 | typedef void *(CPERLscope(*protect_proc_t)) (pTHX_ volatile JMPENV *pcur_env, |
| 307 | int *, protect_body_t, ...); |
| 308 | |
| 309 | #define dJMPENV JMPENV cur_env; \ |
| 310 | volatile JMPENV *pcur_env = ((cur_env.je_noset = 0),&cur_env) |
| 311 | |
| 312 | #define JMPENV_PUSH_INIT_ENV(ce,THROWFUNC) \ |
| 313 | STMT_START { \ |
| 314 | (ce).je_throw = (THROWFUNC); \ |
| 315 | (ce).je_ret = -1; \ |
| 316 | (ce).je_mustcatch = FALSE; \ |
| 317 | (ce).je_prev = PL_top_env; \ |
| 318 | PL_top_env = &(ce); \ |
| 319 | OP_REG_TO_MEM; \ |
| 320 | } STMT_END |
| 321 | |
| 322 | #define JMPENV_PUSH_INIT(THROWFUNC) JMPENV_PUSH_INIT_ENV(*(JMPENV*)pcur_env,THROWFUNC) |
| 323 | |
| 324 | #define JMPENV_POST_CATCH_ENV(ce) \ |
| 325 | STMT_START { \ |
| 326 | OP_MEM_TO_REG; \ |
| 327 | PL_top_env = &(ce); \ |
| 328 | } STMT_END |
| 329 | |
| 330 | #define JMPENV_POST_CATCH JMPENV_POST_CATCH_ENV(*(JMPENV*)pcur_env) |
| 331 | |
| 332 | #define JMPENV_PUSH_ENV(ce,v) \ |
| 333 | STMT_START { \ |
| 334 | if (!(ce).je_noset) { \ |
| 335 | DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \ |
| 336 | ce, PL_top_env)); \ |
| 337 | JMPENV_PUSH_INIT_ENV(ce,NULL); \ |
| 338 | EXCEPT_SET_ENV(ce,PerlProc_setjmp((ce).je_buf, SCOPE_SAVES_SIGNAL_MASK));\ |
| 339 | (ce).je_noset = 1; \ |
| 340 | } \ |
| 341 | else \ |
| 342 | EXCEPT_SET_ENV(ce,0); \ |
| 343 | JMPENV_POST_CATCH_ENV(ce); \ |
| 344 | (v) = EXCEPT_GET_ENV(ce); \ |
| 345 | } STMT_END |
| 346 | |
| 347 | #define JMPENV_PUSH(v) JMPENV_PUSH_ENV(*(JMPENV*)pcur_env,v) |
| 348 | |
| 349 | #define JMPENV_POP_ENV(ce) \ |
| 350 | STMT_START { \ |
| 351 | if (PL_top_env == &(ce)) \ |
| 352 | PL_top_env = (ce).je_prev; \ |
| 353 | } STMT_END |
| 354 | |
| 355 | #define JMPENV_POP JMPENV_POP_ENV(*(JMPENV*)pcur_env) |
| 356 | |
| 357 | #define JMPENV_JUMP(v) \ |
| 358 | STMT_START { \ |
| 359 | OP_REG_TO_MEM; \ |
| 360 | if (PL_top_env->je_prev) { \ |
| 361 | if (PL_top_env->je_throw) \ |
| 362 | PL_top_env->je_throw(v); \ |
| 363 | else \ |
| 364 | PerlProc_longjmp(PL_top_env->je_buf, (v)); \ |
| 365 | } \ |
| 366 | if ((v) == 2) \ |
| 367 | PerlProc_exit(STATUS_NATIVE_EXPORT); \ |
| 368 | PerlIO_printf(Perl_error_log, "panic: top_env\n"); \ |
| 369 | PerlProc_exit(1); \ |
| 370 | } STMT_END |
| 371 | |
| 372 | #define EXCEPT_GET_ENV(ce) ((ce).je_ret) |
| 373 | #define EXCEPT_GET EXCEPT_GET_ENV(*(JMPENV*)pcur_env) |
| 374 | #define EXCEPT_SET_ENV(ce,v) ((ce).je_ret = (v)) |
| 375 | #define EXCEPT_SET(v) EXCEPT_SET_ENV(*(JMPENV*)pcur_env,v) |
| 376 | |
| 377 | #else /* !PERL_FLEXIBLE_EXCEPTIONS */ |
| 378 | |
| 379 | #define dJMPENV JMPENV cur_env |
| 380 | |
| 381 | #define JMPENV_PUSH(v) \ |
| 382 | STMT_START { \ |
| 383 | DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \ |
| 384 | &cur_env, PL_top_env)); \ |
| 385 | cur_env.je_prev = PL_top_env; \ |
| 386 | OP_REG_TO_MEM; \ |
| 387 | cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK); \ |
| 388 | OP_MEM_TO_REG; \ |
| 389 | PL_top_env = &cur_env; \ |
| 390 | cur_env.je_mustcatch = FALSE; \ |
| 391 | (v) = cur_env.je_ret; \ |
| 392 | } STMT_END |
| 393 | |
| 394 | #define JMPENV_POP \ |
| 395 | STMT_START { PL_top_env = cur_env.je_prev; } STMT_END |
| 396 | |
| 397 | #define JMPENV_JUMP(v) \ |
| 398 | STMT_START { \ |
| 399 | OP_REG_TO_MEM; \ |
| 400 | if (PL_top_env->je_prev) \ |
| 401 | PerlProc_longjmp(PL_top_env->je_buf, (v)); \ |
| 402 | if ((v) == 2) \ |
| 403 | PerlProc_exit(STATUS_NATIVE_EXPORT); \ |
| 404 | PerlIO_printf(PerlIO_stderr(), "panic: top_env\n"); \ |
| 405 | PerlProc_exit(1); \ |
| 406 | } STMT_END |
| 407 | |
| 408 | #endif /* PERL_FLEXIBLE_EXCEPTIONS */ |
| 409 | |
| 410 | #define CATCH_GET (PL_top_env->je_mustcatch) |
| 411 | #define CATCH_SET(v) (PL_top_env->je_mustcatch = (v)) |