/* cop.h
*
* Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- * 2000, 2001, 2002, 2003, by Larry Wall and others
+ * 2000, 2001, 2002, 2003, 2004, by Larry Wall and others
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
* and thus can be used to determine our current state.
*/
+/* 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()? */
+};
+
+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
+
+/*
+ * PERL_FLEXIBLE_EXCEPTIONS
+ *
+ * All the flexible exceptions code has been removed.
+ * See the following threads for details:
+ *
+ * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
+ *
+ * Joshua's original patches (which weren't applied) and discussion:
+ *
+ * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
+ * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
+ * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
+ * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
+ * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
+ * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
+ *
+ * Chip's reworked patch and discussion:
+ *
+ * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
+ *
+ * The flaw in these patches (which went unnoticed at the time) was
+ * that they moved some code that could potentially die() out of the
+ * region protected by the setjmp()s. This caused exceptions within
+ * END blocks and such to not be handled by the correct setjmp().
+ *
+ * The original patches that introduces flexible exceptions were:
+ *
+ * http://public.activestate.com/cgi-bin/perlbrowse?patch=3386
+ * http://public.activestate.com/cgi-bin/perlbrowse?patch=5162
+ */
+
+#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 { \
+ DEBUG_l(Perl_deb(aTHX_ "popping jumplevel was %p, now %p\n", \
+ PL_top_env, cur_env.je_prev)); \
+ 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
+
+#define CATCH_GET (PL_top_env->je_mustcatch)
+#define CATCH_SET(v) (PL_top_env->je_mustcatch = (v))
+
+
+
struct cop {
BASEOP
char * cop_label; /* label for this construct */
U8 hasargs;
U8 lval; /* XXX merge lval and hasargs? */
PAD *oldcomppad;
+ OP * retop; /* op to execute on exit from sub */
};
-/* base for the next two macros. Don't use directly */
+/* base for the next two macros. Don't use directly.
+ * Note that the refcnt of the cv is incremented twice; The CX one is
+ * decremented by LEAVESUB, the other by LEAVE. */
+
#define PUSHSUB_BASE(cx) \
cx->blk_sub.cv = cv; \
cx->blk_sub.olddepth = CvDEPTH(cv); \
- cx->blk_sub.hasargs = hasargs;
+ cx->blk_sub.hasargs = hasargs; \
+ cx->blk_sub.retop = Nullop; \
+ if (!CvDEPTH(cv)) { \
+ (void)SvREFCNT_inc(cv); \
+ (void)SvREFCNT_inc(cv); \
+ SAVEFREESV(cv); \
+ }
+
#define PUSHSUB(cx) \
PUSHSUB_BASE(cx) \
#define PUSHFORMAT(cx) \
cx->blk_sub.cv = cv; \
cx->blk_sub.gv = gv; \
+ cx->blk_sub.retop = Nullop; \
cx->blk_sub.hasargs = 0; \
cx->blk_sub.dfoutgv = PL_defoutgv; \
(void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
#define CLEAR_ARGARRAY(ary) \
STMT_START { \
AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary); \
- SvPVX(ary) = (char*)AvALLOC(ary); \
+ SvPV_set(ary, (char*)AvALLOC(ary)); \
AvFILLp(ary) = -1; \
} STMT_END
OP * old_eval_root;
SV * cur_text;
CV * cv;
+ OP * retop; /* op to execute on exit from eval */
};
#define PUSHEVAL(cx,n,fgv) \
cx->blk_eval.old_eval_root = PL_eval_root; \
cx->blk_eval.cur_text = PL_linestr; \
cx->blk_eval.cv = Nullcv; /* set by doeval(), as applicable */ \
+ cx->blk_eval.retop = Nullop; \
} STMT_END
#define POPEVAL(cx) \
struct block {
I32 blku_oldsp; /* stack pointer to copy stuff down to */
COP * blku_oldcop; /* old curcop pointer */
- I32 blku_oldretsp; /* return stack index */
I32 blku_oldmarksp; /* mark stack index */
I32 blku_oldscopesp; /* scope stack index */
PMOP * blku_oldpm; /* values of pattern match vars */
};
#define blk_oldsp cx_u.cx_blk.blku_oldsp
#define blk_oldcop cx_u.cx_blk.blku_oldcop
-#define blk_oldretsp cx_u.cx_blk.blku_oldretsp
#define blk_oldmarksp cx_u.cx_blk.blku_oldmarksp
#define blk_oldscopesp cx_u.cx_blk.blku_oldscopesp
#define blk_oldpm cx_u.cx_blk.blku_oldpm
cx->blk_oldcop = PL_curcop, \
cx->blk_oldmarksp = PL_markstack_ptr - PL_markstack, \
cx->blk_oldscopesp = PL_scopestack_ix, \
- cx->blk_oldretsp = PL_retstack_ix, \
cx->blk_oldpm = PL_curpm, \
cx->blk_gimme = (U8)gimme; \
DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n", \
PL_curcop = cx->blk_oldcop, \
PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp, \
PL_scopestack_ix = cx->blk_oldscopesp, \
- PL_retstack_ix = cx->blk_oldretsp, \
pm = cx->blk_oldpm, \
gimme = cx->blk_gimme; \
DEBUG_SCOPE("POPBLOCK"); \
PL_stack_sp = PL_stack_base + cx->blk_oldsp, \
PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp, \
PL_scopestack_ix = cx->blk_oldscopesp, \
- PL_retstack_ix = cx->blk_oldretsp, \
PL_curpm = cx->blk_oldpm; \
DEBUG_SCOPE("TOPBLOCK");
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