1 /* scope.h 2 * 3 * Copyright (C) 1993, 1994, 1996, 1997, 1998, 1999, 4 * 2000, 2001, 2002, 2004, 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 51 #ifndef SCOPE_SAVES_SIGNAL_MASK 52 #define SCOPE_SAVES_SIGNAL_MASK 0 53 #endif 54 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) 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)) 59 #define SSPUSHBOOL(p) (PL_savestack[PL_savestack_ix++].any_bool = (p)) 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)) 63 #define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p)) 64 #define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32) 65 #define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long) 66 #define SSPOPBOOL (PL_savestack[--PL_savestack_ix].any_bool) 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) 70 #define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr) 71 72 /* 73 =head1 Callback Functions 74 75 =for apidoc Ams||SAVETMPS 76 Opening bracket for temporaries on a callback. See C<FREETMPS> and 77 L<perlcall>. 78 79 =for apidoc Ams||FREETMPS 80 Closing bracket for temporaries on a callback. See C<SAVETMPS> and 81 L<perlcall>. 82 83 =for apidoc Ams||ENTER 84 Opening bracket on a callback. See C<LEAVE> and L<perlcall>. 85 86 =for apidoc Ams||LEAVE 87 Closing bracket on a callback. See C<ENTER> and L<perlcall>. 88 89 =cut 90 */ 91 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() 94 95 #ifdef DEBUGGING 96 #define ENTER \ 97 STMT_START { \ 98 push_scope(); \ 99 DEBUG_SCOPE("ENTER") \ 100 } STMT_END 101 #define LEAVE \ 102 STMT_START { \ 103 DEBUG_SCOPE("LEAVE") \ 104 pop_scope(); \ 105 } STMT_END 106 #else 107 #define ENTER push_scope() 108 #define LEAVE pop_scope() 109 #endif 110 #define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old) 111 112 /* 113 * Not using SOFT_CAST on SAVESPTR, SAVEGENERICSV and SAVEFREESV 114 * because these are used for several kinds of pointer values 115 */ 116 #define SAVEI8(i) save_I8(SOFT_CAST(I8*)&(i)) 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)) 122 #define SAVEBOOL(b) save_bool(SOFT_CAST(bool*)&(b)) 123 #define SAVESPTR(s) save_sptr((SV**)&(s)) 124 #define SAVEPPTR(s) save_pptr(SOFT_CAST(char**)&(s)) 125 #define SAVEVPTR(s) save_vptr((void*)&(s)) 126 #define SAVEPADSV(s) save_padsv(s) 127 #define SAVEFREESV(s) save_freesv((SV*)(s)) 128 #define SAVEMORTALIZESV(s) save_mortalizesv((SV*)(s)) 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)) 132 #define SAVEGENERICSV(s) save_generic_svref((SV**)&(s)) 133 #define SAVEGENERICPV(s) save_generic_pvref((char**)&(s)) 134 #define SAVESHAREDPV(s) save_shared_pvref((char**)&(s)) 135 #define SAVEDELETE(h,k,l) \ 136 save_delete(SOFT_CAST(HV*)(h), SOFT_CAST(char*)(k), (I32)(l)) 137 #define SAVEDESTRUCTOR(f,p) \ 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)) 142 143 #define SAVESTACK_POS() \ 144 STMT_START { \ 145 SSCHECK(2); \ 146 SSPUSHINT(PL_stack_sp - PL_stack_base); \ 147 SSPUSHINT(SAVEt_STACK_POS); \ 148 } STMT_END 149 150 #define SAVEOP() save_op() 151 152 #define SAVEHINTS() \ 153 STMT_START { \ 154 SSCHECK(3); \ 155 if (PL_hints & HINT_LOCALIZE_HH) { \ 156 SSPUSHPTR(GvHV(PL_hintgv)); \ 157 GvHV(PL_hintgv) = newHVhv(GvHV(PL_hintgv)); \ 158 } \ 159 SSPUSHINT(PL_hints); \ 160 SSPUSHINT(SAVEt_HINTS); \ 161 } STMT_END 162 163 #define SAVECOMPPAD() \ 164 STMT_START { \ 165 SSCHECK(2); \ 166 SSPUSHPTR((SV*)PL_comppad); \ 167 SSPUSHINT(SAVEt_COMPPAD); \ 168 } STMT_END 169 170 #ifdef USE_ITHREADS 171 # define SAVECOPSTASH(c) SAVEPPTR(CopSTASHPV(c)) 172 # define SAVECOPSTASH_FREE(c) SAVESHAREDPV(CopSTASHPV(c)) 173 # define SAVECOPFILE(c) SAVEPPTR(CopFILE(c)) 174 # define SAVECOPFILE_FREE(c) SAVESHAREDPV(CopFILE(c)) 175 #else 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)) 180 #endif 181 182 #define SAVECOPLINE(c) SAVEI32(CopLINE(c)) 183 184 /* 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 */ 194 195 #define SSNEW(size) Perl_save_alloc(aTHX_ (size), 0) 196 #define SSNEWt(n,t) SSNEW((n)*sizeof(t)) 197 #define SSNEWa(size,align) Perl_save_alloc(aTHX_ (size), \ 198 (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align) 199 #define SSNEWat(n,t,align) SSNEWa((n)*sizeof(t), align) 200 201 #define SSPTR(off,type) ((type) ((char*)PL_savestack + off)) 202 #define SSPTRt(off,type) ((type*) ((char*)PL_savestack + off)) 203 204 /* 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 209 * longjmp() at that runlevel (we make sure start_env.je_prev is always 210 * null to ensure this). 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. 216 * GSAR 97-03-27 217 */ 218 219 struct jmpenv { 220 struct jmpenv * je_prev; 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()? */ 224 #ifdef PERL_FLEXIBLE_EXCEPTIONS 225 void (*je_throw)(int v); /* last for bincompat */ 226 bool je_noset; /* no need for setjmp() */ 227 #endif 228 }; 229 230 typedef struct jmpenv JMPENV; 231 232 #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 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 { \ 252 Zero(&PL_start_env, 1, JMPENV); \ 253 PL_start_env.je_ret = -1; \ 254 PL_start_env.je_mustcatch = TRUE; \ 255 PL_top_env = &PL_start_env; \ 256 } STMT_END 257 258 #ifdef PERL_FLEXIBLE_EXCEPTIONS 259 260 /* 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 */ 289 290 /* 291 * Function that catches/throws, and its callback for the 292 * body of protected processing. 293 */ 294 typedef void *(CPERLscope(*protect_body_t)) (pTHX_ va_list); 295 typedef void *(CPERLscope(*protect_proc_t)) (pTHX_ volatile JMPENV *pcur_env, 296 int *, protect_body_t, ...); 297 298 #define dJMPENV JMPENV cur_env; \ 299 volatile JMPENV *pcur_env = ((cur_env.je_noset = 0),&cur_env) 300 301 #define JMPENV_PUSH_INIT_ENV(ce,THROWFUNC) \ 302 STMT_START { \ 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); \ 308 OP_REG_TO_MEM; \ 309 } STMT_END 310 311 #define JMPENV_PUSH_INIT(THROWFUNC) JMPENV_PUSH_INIT_ENV(*(JMPENV*)pcur_env,THROWFUNC) 312 313 #define JMPENV_POST_CATCH_ENV(ce) \ 314 STMT_START { \ 315 OP_MEM_TO_REG; \ 316 PL_top_env = &(ce); \ 317 } STMT_END 318 319 #define JMPENV_POST_CATCH JMPENV_POST_CATCH_ENV(*(JMPENV*)pcur_env) 320 321 #define JMPENV_PUSH_ENV(ce,v) \ 322 STMT_START { \ 323 if (!(ce).je_noset) { \ 324 DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \ 325 ce, PL_top_env)); \ 326 JMPENV_PUSH_INIT_ENV(ce,NULL); \ 327 EXCEPT_SET_ENV(ce,PerlProc_setjmp((ce).je_buf, SCOPE_SAVES_SIGNAL_MASK));\ 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); \ 334 } STMT_END 335 336 #define JMPENV_PUSH(v) JMPENV_PUSH_ENV(*(JMPENV*)pcur_env,v) 337 338 #define JMPENV_POP_ENV(ce) \ 339 STMT_START { \ 340 if (PL_top_env == &(ce)) \ 341 PL_top_env = (ce).je_prev; \ 342 } STMT_END 343 344 #define JMPENV_POP JMPENV_POP_ENV(*(JMPENV*)pcur_env) 345 346 #define JMPENV_JUMP(v) \ 347 STMT_START { \ 348 OP_REG_TO_MEM; \ 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 } \ 355 if ((v) == 2) \ 356 PerlProc_exit(STATUS_NATIVE_EXPORT); \ 357 PerlIO_printf(Perl_error_log, "panic: top_env\n"); \ 358 PerlProc_exit(1); \ 359 } STMT_END 360 361 #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) 365 366 #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; \ 376 cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK); \ 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 */ 398 399 #define CATCH_GET (PL_top_env->je_mustcatch) 400 #define CATCH_SET(v) (PL_top_env->je_mustcatch = (v)) 401