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