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