/* scope.h
*
* Copyright (c) 1997-2002, Larry Wall
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
*
*/
#define SAVEt_ITEM 0
#define SAVEt_SV 1
#define SAVEt_AV 2
#define SAVEt_HV 3
#define SAVEt_INT 4
#define SAVEt_LONG 5
#define SAVEt_I32 6
#define SAVEt_IV 7
#define SAVEt_SPTR 8
#define SAVEt_APTR 9
#define SAVEt_HPTR 10
#define SAVEt_PPTR 11
#define SAVEt_NSTAB 12
#define SAVEt_SVREF 13
#define SAVEt_GP 14
#define SAVEt_FREESV 15
#define SAVEt_FREEOP 16
#define SAVEt_FREEPV 17
#define SAVEt_CLEARSV 18
#define SAVEt_DELETE 19
#define SAVEt_DESTRUCTOR 20
#define SAVEt_REGCONTEXT 21
#define SAVEt_STACK_POS 22
#define SAVEt_I16 23
#define SAVEt_AELEM 24
#define SAVEt_HELEM 25
#define SAVEt_OP 26
#define SAVEt_HINTS 27
#define SAVEt_ALLOC 28
#define SAVEt_GENERIC_SVREF 29
#define SAVEt_DESTRUCTOR_X 30
#define SAVEt_VPTR 31
#define SAVEt_I8 32
#define SAVEt_COMPPAD 33
#define SAVEt_GENERIC_PVREF 34
#define SAVEt_PADSV 35
#define SAVEt_MORTALIZESV 36
#define SAVEt_SHARED_PVREF 37
#ifndef SCOPE_SAVES_SIGNAL_MASK
#define SCOPE_SAVES_SIGNAL_MASK 0
#endif
#define SSCHECK(need) if (PL_savestack_ix + need > PL_savestack_max) savestack_grow()
#define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
#define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
#define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
#define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
#define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
#define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p))
#define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
#define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
#define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
#define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
#define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
#define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr)
/*
=head1 Callback Functions
=for apidoc Ams||SAVETMPS
Opening bracket for temporaries on a callback. See C<FREETMPS> and
L<perlcall>.
=for apidoc Ams||FREETMPS
Closing bracket for temporaries on a callback. See C<SAVETMPS> and
L<perlcall>.
=for apidoc Ams||ENTER
Opening bracket on a callback. See C<LEAVE> and L<perlcall>.
=for apidoc Ams||LEAVE
Closing bracket on a callback. See C<ENTER> and L<perlcall>.
=cut
*/
#define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix
#define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
#ifdef DEBUGGING
#define ENTER \
STMT_START { \
push_scope(); \
DEBUG_l(WITH_THR(Perl_deb(aTHX_ "ENTER scope %ld at %s:%d\n", \
PL_scopestack_ix, __FILE__, __LINE__))); \
} STMT_END
#define LEAVE \
STMT_START { \
DEBUG_l(WITH_THR(Perl_deb(aTHX_ "LEAVE scope %ld at %s:%d\n", \
PL_scopestack_ix, __FILE__, __LINE__))); \
pop_scope(); \
} STMT_END
#else
#define ENTER push_scope()
#define LEAVE pop_scope()
#endif
#define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old)
/*
* Not using SOFT_CAST on SAVESPTR, SAVEGENERICSV and SAVEFREESV
* because these are used for several kinds of pointer values
*/
#define SAVEI8(i) save_I8(SOFT_CAST(I8*)&(i))
#define SAVEI16(i) save_I16(SOFT_CAST(I16*)&(i))
#define SAVEI32(i) save_I32(SOFT_CAST(I32*)&(i))
#define SAVEINT(i) save_int(SOFT_CAST(int*)&(i))
#define SAVEIV(i) save_iv(SOFT_CAST(IV*)&(i))
#define SAVELONG(l) save_long(SOFT_CAST(long*)&(l))
#define SAVESPTR(s) save_sptr((SV**)&(s))
#define SAVEPPTR(s) save_pptr(SOFT_CAST(char**)&(s))
#define SAVEVPTR(s) save_vptr((void*)&(s))
#define SAVEPADSV(s) save_padsv(s)
#define SAVEFREESV(s) save_freesv((SV*)(s))
#define SAVEMORTALIZESV(s) save_mortalizesv((SV*)(s))
#define SAVEFREEOP(o) save_freeop(SOFT_CAST(OP*)(o))
#define SAVEFREEPV(p) save_freepv(SOFT_CAST(char*)(p))
#define SAVECLEARSV(sv) save_clearsv(SOFT_CAST(SV**)&(sv))
#define SAVEGENERICSV(s) save_generic_svref((SV**)&(s))
#define SAVEGENERICPV(s) save_generic_pvref((char**)&(s))
#define SAVESHAREDPV(s) save_shared_pvref((char**)&(s))
#define SAVEDELETE(h,k,l) \
save_delete(SOFT_CAST(HV*)(h), SOFT_CAST(char*)(k), (I32)(l))
#define SAVEDESTRUCTOR(f,p) \
save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), SOFT_CAST(void*)(p))
#define SAVEDESTRUCTOR_X(f,p) \
save_destructor_x((DESTRUCTORFUNC_t)(f), SOFT_CAST(void*)(p))
#define SAVESTACK_POS() \
STMT_START { \
SSCHECK(2); \
SSPUSHINT(PL_stack_sp - PL_stack_base); \
SSPUSHINT(SAVEt_STACK_POS); \
} STMT_END
#define SAVEOP() save_op()
#define SAVEHINTS() \
STMT_START { \
if (PL_hints & HINT_LOCALIZE_HH) \
save_hints(); \
else { \
SSCHECK(2); \
SSPUSHINT(PL_hints); \
SSPUSHINT(SAVEt_HINTS); \
} \
} STMT_END
#define SAVECOMPPAD() \
STMT_START { \
if (PL_comppad && PL_curpad == AvARRAY(PL_comppad)) { \
SSCHECK(2); \
SSPUSHPTR((SV*)PL_comppad); \
SSPUSHINT(SAVEt_COMPPAD); \
} \
else { \
SAVEVPTR(PL_curpad); \
SAVESPTR(PL_comppad); \
} \
} STMT_END
#ifdef USE_ITHREADS
# define SAVECOPSTASH(c) SAVEPPTR(CopSTASHPV(c))
# define SAVECOPSTASH_FREE(c) SAVESHAREDPV(CopSTASHPV(c))
# define SAVECOPFILE(c) SAVEPPTR(CopFILE(c))
# define SAVECOPFILE_FREE(c) SAVESHAREDPV(CopFILE(c))
#else
# define SAVECOPSTASH(c) SAVESPTR(CopSTASH(c))
# define SAVECOPSTASH_FREE(c) SAVECOPSTASH(c) /* XXX not refcounted */
# define SAVECOPFILE(c) SAVESPTR(CopFILEGV(c))
# define SAVECOPFILE_FREE(c) SAVEGENERICSV(CopFILEGV(c))
#endif
#define SAVECOPLINE(c) SAVEI16(CopLINE(c))
/* SSNEW() temporarily allocates a specified number of bytes of data on the
* savestack. It returns an integer index into the savestack, because a
* pointer would get broken if the savestack is moved on reallocation.
* SSNEWa() works like SSNEW(), but also aligns the data to the specified
* number of bytes. MEM_ALIGNBYTES is perhaps the most useful. The
* alignment will be preserved therough savestack reallocation *only* if
* realloc returns data aligned to a size divisible by `align'!
*
* SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
*/
#define SSNEW(size) Perl_save_alloc(aTHX_ (size), 0)
#define SSNEWt(n,t) SSNEW((n)*sizeof(t))
#define SSNEWa(size,align) Perl_save_alloc(aTHX_ (size), \
(align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
#define SSNEWat(n,t,align) SSNEWa((n)*sizeof(t), align)
#define SSPTR(off,type) ((type) ((char*)PL_savestack + off))
#define SSPTRt(off,type) ((type*) ((char*)PL_savestack + off))
/* A jmpenv packages the state required to perform a proper non-local jump.
* Note that there is a start_env initialized when perl starts, and top_env
* points to this initially, so top_env should always be non-null.
*
* Existence of a non-null top_env->je_prev implies it is valid to call
* longjmp() at that runlevel (we make sure start_env.je_prev is always
* null to ensure this).
*
* je_mustcatch, when set at any runlevel to TRUE, means eval ops must
* establish a local jmpenv to handle exception traps. Care must be taken
* to restore the previous value of je_mustcatch before exiting the
* stack frame iff JMPENV_PUSH was not called in that stack frame.
* GSAR 97-03-27
*/
struct jmpenv {
struct jmpenv * je_prev;
Sigjmp_buf je_buf; /* only for use if !je_throw */
int je_ret; /* last exception thrown */
bool je_mustcatch; /* need to call longjmp()? */
#ifdef PERL_FLEXIBLE_EXCEPTIONS
void (*je_throw)(int v); /* last for bincompat */
bool je_noset; /* no need for setjmp() */
#endif
};
typedef struct jmpenv JMPENV;
#ifdef OP_IN_REGISTER
#define OP_REG_TO_MEM PL_opsave = op
#define OP_MEM_TO_REG op = PL_opsave
#else
#define OP_REG_TO_MEM NOOP
#define OP_MEM_TO_REG NOOP
#endif
/*
* How to build the first jmpenv.
*
* top_env needs to be non-zero. It points to an area
* in which longjmp() stuff is stored, as C callstack
* info there at least is thread specific this has to
* be per-thread. Otherwise a 'die' in a thread gives
* that thread the C stack of last thread to do an eval {}!
*/
#define JMPENV_BOOTSTRAP \
STMT_START { \
Zero(&PL_start_env, 1, JMPENV); \
PL_start_env.je_ret = -1; \
PL_start_env.je_mustcatch = TRUE; \
PL_top_env = &PL_start_env; \
} STMT_END
#ifdef PERL_FLEXIBLE_EXCEPTIONS
/*
* These exception-handling macros are split up to
* ease integration with C++ exceptions.
*
* To use C++ try+catch to catch Perl exceptions, an extension author
* needs to first write an extern "C" function to throw an appropriate
* exception object; typically it will be or contain an integer,
* because Perl's internals use integers to track exception types:
* extern "C" { static void thrower(int i) { throw i; } }
*
* Then (as shown below) the author needs to use, not the simple
* JMPENV_PUSH, but several of its constitutent macros, to arrange for
* the Perl internals to call thrower() rather than longjmp() to
* report exceptions:
*
* dJMPENV;
* JMPENV_PUSH_INIT(thrower);
* try {
* ... stuff that may throw exceptions ...
* }
* catch (int why) { // or whatever matches thrower()
* JMPENV_POST_CATCH;
* EXCEPT_SET(why);
* switch (why) {
* ... // handle various Perl exception codes
* }
* }
* JMPENV_POP; // don't forget this!
*/
/*
* Function that catches/throws, and its callback for the
* body of protected processing.
*/
typedef void *(CPERLscope(*protect_body_t)) (pTHX_ va_list);
typedef void *(CPERLscope(*protect_proc_t)) (pTHX_ volatile JMPENV *pcur_env,
int *, protect_body_t, ...);
#define dJMPENV JMPENV cur_env; \
volatile JMPENV *pcur_env = ((cur_env.je_noset = 0),&cur_env)
#define JMPENV_PUSH_INIT_ENV(ce,THROWFUNC) \
STMT_START { \
(ce).je_throw = (THROWFUNC); \
(ce).je_ret = -1; \
(ce).je_mustcatch = FALSE; \
(ce).je_prev = PL_top_env; \
PL_top_env = &(ce); \
OP_REG_TO_MEM; \
} STMT_END
#define JMPENV_PUSH_INIT(THROWFUNC) JMPENV_PUSH_INIT_ENV(*(JMPENV*)pcur_env,THROWFUNC)
#define JMPENV_POST_CATCH_ENV(ce) \
STMT_START { \
OP_MEM_TO_REG; \
PL_top_env = &(ce); \
} STMT_END
#define JMPENV_POST_CATCH JMPENV_POST_CATCH_ENV(*(JMPENV*)pcur_env)
#define JMPENV_PUSH_ENV(ce,v) \
STMT_START { \
if (!(ce).je_noset) { \
DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \
ce, PL_top_env)); \
JMPENV_PUSH_INIT_ENV(ce,NULL); \
EXCEPT_SET_ENV(ce,PerlProc_setjmp((ce).je_buf, SCOPE_SAVES_SIGNAL_MASK));\
(ce).je_noset = 1; \
} \
else \
EXCEPT_SET_ENV(ce,0); \
JMPENV_POST_CATCH_ENV(ce); \
(v) = EXCEPT_GET_ENV(ce); \
} STMT_END
#define JMPENV_PUSH(v) JMPENV_PUSH_ENV(*(JMPENV*)pcur_env,v)
#define JMPENV_POP_ENV(ce) \
STMT_START { \
if (PL_top_env == &(ce)) \
PL_top_env = (ce).je_prev; \
} STMT_END
#define JMPENV_POP JMPENV_POP_ENV(*(JMPENV*)pcur_env)
#define JMPENV_JUMP(v) \
STMT_START { \
OP_REG_TO_MEM; \
if (PL_top_env->je_prev) { \
if (PL_top_env->je_throw) \
PL_top_env->je_throw(v); \
else \
PerlProc_longjmp(PL_top_env->je_buf, (v)); \
} \
if ((v) == 2) \
PerlProc_exit(STATUS_NATIVE_EXPORT); \
PerlIO_printf(Perl_error_log, "panic: top_env\n"); \
PerlProc_exit(1); \
} STMT_END
#define EXCEPT_GET_ENV(ce) ((ce).je_ret)
#define EXCEPT_GET EXCEPT_GET_ENV(*(JMPENV*)pcur_env)
#define EXCEPT_SET_ENV(ce,v) ((ce).je_ret = (v))
#define EXCEPT_SET(v) EXCEPT_SET_ENV(*(JMPENV*)pcur_env,v)
#else /* !PERL_FLEXIBLE_EXCEPTIONS */
#define dJMPENV JMPENV cur_env
#define JMPENV_PUSH(v) \
STMT_START { \
DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n", \
&cur_env, PL_top_env)); \
cur_env.je_prev = PL_top_env; \
OP_REG_TO_MEM; \
cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK); \
OP_MEM_TO_REG; \
PL_top_env = &cur_env; \
cur_env.je_mustcatch = FALSE; \
(v) = cur_env.je_ret; \
} STMT_END
#define JMPENV_POP \
STMT_START { PL_top_env = cur_env.je_prev; } STMT_END
#define JMPENV_JUMP(v) \
STMT_START { \
OP_REG_TO_MEM; \
if (PL_top_env->je_prev) \
PerlProc_longjmp(PL_top_env->je_buf, (v)); \
if ((v) == 2) \
PerlProc_exit(STATUS_NATIVE_EXPORT); \
PerlIO_printf(PerlIO_stderr(), "panic: top_env\n"); \
PerlProc_exit(1); \
} STMT_END
#endif /* PERL_FLEXIBLE_EXCEPTIONS */
#define CATCH_GET (PL_top_env->je_mustcatch)
#define CATCH_SET(v) (PL_top_env->je_mustcatch = (v))
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