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