[p5sagit/p5-mst-13.2.git] / scope.h

#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 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)

/*
=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 SAVEFREESV(s)	save_freesv((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 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

#ifdef USE_ITHREADS
#  define SAVECOPSTASH(cop)	SAVEPPTR(CopSTASHPV(cop))
#  define SAVECOPFILE(cop)	SAVEPPTR(CopFILE(cop))
#else
#  define SAVECOPSTASH(cop)	SAVESPTR(CopSTASH(cop))
#  define SAVECOPFILE(cop)	SAVESPTR(CopFILEGV(cop))
#endif

#define SAVECOPLINE(cop)	SAVEI16(CopLINE(cop))

/* 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)             save_alloc(size, 0)
#define SSNEWa(size,align)	save_alloc(size, \
    (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)

#define SSPTR(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()? */
    void		(*je_throw)(int v); /* last for bincompat */
    bool		je_noset;	/* no need for setjmp() */
};

typedef struct jmpenv JMPENV;

/*
 * 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, ...);

/*
 * 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 {				\
	PL_start_env.je_prev = NULL;		\
	PL_start_env.je_throw = NULL;		\
	PL_start_env.je_ret = -1;		\
	PL_start_env.je_mustcatch = TRUE;	\
	PL_start_env.je_noset = 0;		\
	PL_top_env = &PL_start_env;		\
    } STMT_END

#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

/*
 * 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!
 */

#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) {					\
	    JMPENV_PUSH_INIT_ENV(ce,NULL);			\
	    EXCEPT_SET_ENV(ce,PerlProc_setjmp((ce).je_buf, 1));\
	    (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 { 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)

#define CATCH_GET		(PL_top_env->je_mustcatch)
#define CATCH_SET(v)		(PL_top_env->je_mustcatch = (v))
Commit	Line	Data
b9d12d37	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
c76ac1ee	31	#define SAVEt_DESTRUCTOR_X 30
7766f137	32	#define SAVEt_VPTR 31
e8347627	33	#define SAVEt_I8 32
79072805	34
3280af22	35	#define SSCHECK(need) if (PL_savestack_ix + need > PL_savestack_max) savestack_grow()
	36	#define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
	37	#define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
	38	#define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
	39	#define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
	40	#define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
c76ac1ee	41	#define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p))
3280af22	42	#define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
	43	#define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
	44	#define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
	45	#define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
	46	#define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
c76ac1ee	47	#define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr)
8990e307	48
954c1994	49	/*
	50	=for apidoc Ams\|\|SAVETMPS
	51	Opening bracket for temporaries on a callback. See C<FREETMPS> and
	52	L<perlcall>.
	53
	54	=for apidoc Ams\|\|FREETMPS
	55	Closing bracket for temporaries on a callback. See C<SAVETMPS> and
	56	L<perlcall>.
	57
	58	=for apidoc Ams\|\|ENTER
	59	Opening bracket on a callback. See C<LEAVE> and L<perlcall>.
	60
	61	=for apidoc Ams\|\|LEAVE
	62	Closing bracket on a callback. See C<ENTER> and L<perlcall>.
	63
	64	=cut
	65	*/
	66
3280af22	67	#define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix
3280af22	68	#define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
a0d0e21e	69
f46d017c	70	#ifdef DEBUGGING
	71	#define ENTER \
	72	STMT_START { \
	73	push_scope(); \
cea2e8a9	74	DEBUG_l(WITH_THR(Perl_deb(aTHX_ "ENTER scope %ld at %s:%d\n", \
3280af22	75	PL_scopestack_ix, __FILE__, __LINE__))); \
f46d017c	76	} STMT_END
	77	#define LEAVE \
	78	STMT_START { \
cea2e8a9	79	DEBUG_l(WITH_THR(Perl_deb(aTHX_ "LEAVE scope %ld at %s:%d\n", \
3280af22	80	PL_scopestack_ix, __FILE__, __LINE__))); \
f46d017c	81	pop_scope(); \
	82	} STMT_END
	83	#else
a0d0e21e	84	#define ENTER push_scope()
a0d0e21e	85	#define LEAVE pop_scope()
f46d017c	86	#endif
3280af22	87	#define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old)
a0d0e21e	88
55497cff	89	/*
b9d12d37	90	* Not using SOFT_CAST on SAVESPTR, SAVEGENERICSV and SAVEFREESV
55497cff	91	* because these are used for several kinds of pointer values
55497cff	92	*/
e8347627	93	#define SAVEI8(i) save_I8(SOFT_CAST(I8*)&(i))
4fdae800	94	#define SAVEI16(i) save_I16(SOFT_CAST(I16*)&(i))
	95	#define SAVEI32(i) save_I32(SOFT_CAST(I32*)&(i))
	96	#define SAVEINT(i) save_int(SOFT_CAST(int*)&(i))
	97	#define SAVEIV(i) save_iv(SOFT_CAST(IV*)&(i))
	98	#define SAVELONG(l) save_long(SOFT_CAST(long*)&(l))
55497cff	99	#define SAVESPTR(s) save_sptr((SV**)&(s))
55497cff	100	#define SAVEPPTR(s) save_pptr(SOFT_CAST(char**)&(s))
57b2e452	101	#define SAVEVPTR(s) save_vptr((void*)&(s))
55497cff	102	#define SAVEFREESV(s) save_freesv((SV*)(s))
	103	#define SAVEFREEOP(o) save_freeop(SOFT_CAST(OP*)(o))
	104	#define SAVEFREEPV(p) save_freepv(SOFT_CAST(char*)(p))
	105	#define SAVECLEARSV(sv) save_clearsv(SOFT_CAST(SV**)&(sv))
b9d12d37	106	#define SAVEGENERICSV(s) save_generic_svref((SV**)&(s))
55497cff	107	#define SAVEDELETE(h,k,l) \
	108	save_delete(SOFT_CAST(HV)(h), SOFT_CAST(char)(k), (I32)(l))
	109	#define SAVEDESTRUCTOR(f,p) \
c76ac1ee	110	save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), SOFT_CAST(void*)(p))
	111
	112	#define SAVEDESTRUCTOR_X(f,p) \
	113	save_destructor_x((DESTRUCTORFUNC_t)(f), SOFT_CAST(void*)(p))
25eaa213	114
	115	#define SAVESTACK_POS() \
	116	STMT_START { \
	117	SSCHECK(2); \
3280af22	118	SSPUSHINT(PL_stack_sp - PL_stack_base); \
25eaa213	119	SSPUSHINT(SAVEt_STACK_POS); \
	120	} STMT_END
	121
462e5cf6	122	#define SAVEOP() save_op()
25eaa213	123
	124	#define SAVEHINTS() \
	125	STMT_START { \
3280af22	126	if (PL_hints & HINT_LOCALIZE_HH) \
25eaa213	127	save_hints(); \
	128	else { \
	129	SSCHECK(2); \
3280af22	130	SSPUSHINT(PL_hints); \
25eaa213	131	SSPUSHINT(SAVEt_HINTS); \
	132	} \
	133	} STMT_END
a9332b4a	134
57843af0	135	#ifdef USE_ITHREADS
11faa288	136	# define SAVECOPSTASH(cop) SAVEPPTR(CopSTASHPV(cop))
57843af0	137	# define SAVECOPFILE(cop) SAVEPPTR(CopFILE(cop))
57843af0	138	#else
11faa288	139	# define SAVECOPSTASH(cop) SAVESPTR(CopSTASH(cop))
57843af0	140	# define SAVECOPFILE(cop) SAVESPTR(CopFILEGV(cop))
	141	#endif
	142
	143	#define SAVECOPLINE(cop) SAVEI16(CopLINE(cop))
	144
455ece5e	145	/* SSNEW() temporarily allocates a specified number of bytes of data on the
	146	* savestack. It returns an integer index into the savestack, because a
	147	* pointer would get broken if the savestack is moved on reallocation.
	148	* SSNEWa() works like SSNEW(), but also aligns the data to the specified
	149	* number of bytes. MEM_ALIGNBYTES is perhaps the most useful. The
	150	* alignment will be preserved therough savestack reallocation only if
	151	* realloc returns data aligned to a size divisible by `align'!
	152	*
	153	* SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
	154	*/
	155
	156	#define SSNEW(size) save_alloc(size, 0)
	157	#define SSNEWa(size,align) save_alloc(size, \
	158	(align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
	159
	160	#define SSPTR(off,type) ((type) ((char*)PL_savestack + off))
	161
54310121	162	/* A jmpenv packages the state required to perform a proper non-local jump.
	163	* Note that there is a start_env initialized when perl starts, and top_env
	164	* points to this initially, so top_env should always be non-null.
	165	*
	166	* Existence of a non-null top_env->je_prev implies it is valid to call
6224f72b	167	* longjmp() at that runlevel (we make sure start_env.je_prev is always
6224f72b	168	* null to ensure this).
54310121	169	*
	170	* je_mustcatch, when set at any runlevel to TRUE, means eval ops must
	171	* establish a local jmpenv to handle exception traps. Care must be taken
	172	* to restore the previous value of je_mustcatch before exiting the
	173	* stack frame iff JMPENV_PUSH was not called in that stack frame.
6224f72b	174	* GSAR 97-03-27
54310121	175	*/
	176
	177	struct jmpenv {
	178	struct jmpenv * je_prev;
312caa8e	179	Sigjmp_buf je_buf; /* only for use if !je_throw */
	180	int je_ret; /* last exception thrown */
	181	bool je_mustcatch; /* need to call longjmp()? */
	182	void (je_throw)(int v); / last for bincompat */
db36c5a1	183	bool je_noset; /* no need for setjmp() */
1163b5c4	184	};
1163b5c4	185
6224f72b	186	typedef struct jmpenv JMPENV;
1163b5c4	187
312caa8e	188	/*
	189	* Function that catches/throws, and its callback for the
	190	* body of protected processing.
	191	*/
cea2e8a9	192	typedef void (CPERLscope(protect_body_t)) (pTHX_ va_list);
db36c5a1	193	typedef void (CPERLscope(protect_proc_t)) (pTHX_ volatile JMPENV *pcur_env,
db36c5a1	194	int *, protect_body_t, ...);
312caa8e	195
	196	/*
	197	* How to build the first jmpenv.
	198	*
	199	* top_env needs to be non-zero. It points to an area
	200	* in which longjmp() stuff is stored, as C callstack
	201	* info there at least is thread specific this has to
	202	* be per-thread. Otherwise a 'die' in a thread gives
	203	* that thread the C stack of last thread to do an eval {}!
	204	*/
	205
	206	#define JMPENV_BOOTSTRAP \
	207	STMT_START { \
	208	PL_start_env.je_prev = NULL; \
	209	PL_start_env.je_throw = NULL; \
	210	PL_start_env.je_ret = -1; \
	211	PL_start_env.je_mustcatch = TRUE; \
db36c5a1	212	PL_start_env.je_noset = 0; \
312caa8e	213	PL_top_env = &PL_start_env; \
	214	} STMT_END
	215
462e5cf6	216	#ifdef OP_IN_REGISTER
6b88bc9c	217	#define OP_REG_TO_MEM PL_opsave = op
6b88bc9c	218	#define OP_MEM_TO_REG op = PL_opsave
462e5cf6	219	#else
	220	#define OP_REG_TO_MEM NOOP
	221	#define OP_MEM_TO_REG NOOP
	222	#endif
	223
312caa8e	224	/*
	225	* These exception-handling macros are split up to
	226	* ease integration with C++ exceptions.
	227	*
	228	* To use C++ try+catch to catch Perl exceptions, an extension author
	229	* needs to first write an extern "C" function to throw an appropriate
	230	* exception object; typically it will be or contain an integer,
	231	* because Perl's internals use integers to track exception types:
	232	* extern "C" { static void thrower(int i) { throw i; } }
	233	*
	234	* Then (as shown below) the author needs to use, not the simple
	235	* JMPENV_PUSH, but several of its constitutent macros, to arrange for
	236	* the Perl internals to call thrower() rather than longjmp() to
	237	* report exceptions:
	238	*
	239	* dJMPENV;
	240	* JMPENV_PUSH_INIT(thrower);
	241	* try {
	242	* ... stuff that may throw exceptions ...
	243	* }
	244	* catch (int why) { // or whatever matches thrower()
	245	* JMPENV_POST_CATCH;
	246	* EXCEPT_SET(why);
	247	* switch (why) {
	248	* ... // handle various Perl exception codes
	249	* }
	250	* }
	251	* JMPENV_POP; // don't forget this!
	252	*/
	253
db36c5a1	254	#define dJMPENV JMPENV cur_env; \
db36c5a1	255	volatile JMPENV *pcur_env = ((cur_env.je_noset = 0),&cur_env)
312caa8e	256
db36c5a1	257	#define JMPENV_PUSH_INIT_ENV(ce,THROWFUNC) \
6224f72b	258	STMT_START { \
db36c5a1	259	(ce).je_throw = (THROWFUNC); \
	260	(ce).je_ret = -1; \
	261	(ce).je_mustcatch = FALSE; \
	262	(ce).je_prev = PL_top_env; \
	263	PL_top_env = &(ce); \
6224f72b	264	OP_REG_TO_MEM; \
312caa8e	265	} STMT_END
1d651c14	266
db36c5a1	267	#define JMPENV_PUSH_INIT(THROWFUNC) JMPENV_PUSH_INIT_ENV((JMPENV)pcur_env,THROWFUNC)
1d651c14	268
db36c5a1	269	#define JMPENV_POST_CATCH_ENV(ce) \
312caa8e	270	STMT_START { \
6224f72b	271	OP_MEM_TO_REG; \
db36c5a1	272	PL_top_env = &(ce); \
6224f72b	273	} STMT_END
312caa8e	274
db36c5a1	275	#define JMPENV_POST_CATCH JMPENV_POST_CATCH_ENV((JMPENV)pcur_env)
1d651c14	276
1d651c14	277
db36c5a1	278	#define JMPENV_PUSH_ENV(ce,v) \
	279	STMT_START { \
	280	if (!(ce).je_noset) { \
	281	JMPENV_PUSH_INIT_ENV(ce,NULL); \
	282	EXCEPT_SET_ENV(ce,PerlProc_setjmp((ce).je_buf, 1));\
	283	(ce).je_noset = 1; \
	284	} \
	285	else \
	286	EXCEPT_SET_ENV(ce,0); \
	287	JMPENV_POST_CATCH_ENV(ce); \
	288	(v) = EXCEPT_GET_ENV(ce); \
312caa8e	289	} STMT_END
312caa8e	290
db36c5a1	291	#define JMPENV_PUSH(v) JMPENV_PUSH_ENV((JMPENV)pcur_env,v)
1d651c14	292
db36c5a1	293	#define JMPENV_POP_ENV(ce) \
db36c5a1	294	STMT_START { PL_top_env = (ce).je_prev; } STMT_END
312caa8e	295
db36c5a1	296	#define JMPENV_POP JMPENV_POP_ENV((JMPENV)pcur_env)
1d651c14	297
22921e25	298	#define JMPENV_JUMP(v) \
22921e25	299	STMT_START { \
462e5cf6	300	OP_REG_TO_MEM; \
312caa8e	301	if (PL_top_env->je_prev) { \
	302	if (PL_top_env->je_throw) \
	303	PL_top_env->je_throw(v); \
	304	else \
	305	PerlProc_longjmp(PL_top_env->je_buf, (v)); \
	306	} \
6224f72b	307	if ((v) == 2) \
312caa8e	308	PerlProc_exit(STATUS_NATIVE_EXPORT); \
bf49b057	309	PerlIO_printf(Perl_error_log, "panic: top_env\n"); \
312caa8e	310	PerlProc_exit(1); \
22921e25	311	} STMT_END
312caa8e	312
db36c5a1	313	#define EXCEPT_GET_ENV(ce) ((ce).je_ret)
	314	#define EXCEPT_GET EXCEPT_GET_ENV((JMPENV)pcur_env)
	315	#define EXCEPT_SET_ENV(ce,v) ((ce).je_ret = (v))
	316	#define EXCEPT_SET(v) EXCEPT_SET_ENV((JMPENV)pcur_env,v)
312caa8e	317
db36c5a1	318	#define CATCH_GET (PL_top_env->je_mustcatch)
db36c5a1	319	#define CATCH_SET(v) (PL_top_env->je_mustcatch = (v))