scope.h

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