#include "perl.h"
#include "XSUB.h"
+#define __PACKAGE__ "Scope::Upper"
+
#ifndef SU_DEBUG
# define SU_DEBUG 0
#endif
/* --- Compatibility ------------------------------------------------------- */
+#ifndef PERL_UNUSED_VAR
+# define PERL_UNUSED_VAR(V)
+#endif
+
#ifndef STMT_START
# define STMT_START do
#endif
} su_ud_adelete;
STATIC void su_adelete(pTHX_ void *ud_) {
- su_ud_adelete *ud = ud_;
+ su_ud_adelete *ud = (su_ud_adelete *) ud_;
av_delete(ud->av, ud->idx, G_DISCARD);
SvREFCNT_dec(ud->av);
return depth;
}
+/* --- Unwind stack -------------------------------------------------------- */
+
+typedef struct {
+ I32 cxix;
+ I32 items;
+} su_ud_unwind;
+
+STATIC void su_unwind(pTHX_ void *ud_) {
+ su_ud_unwind *ud = (su_ud_unwind *) ud_;
+ OP fakeop;
+ I32 cxix = ud->cxix;
+ I32 items = ud->items - 1;
+ I32 gimme, mark;
+
+ if (cxstack_ix > cxix)
+ dounwind(cxix);
+
+ /* Hide the level */
+ if (items >= 0)
+ PL_stack_sp--;
+
+ mark = PL_markstack[cxstack[cxix].blk_oldmarksp];
+
+ gimme = GIMME_V;
+ if (gimme == G_SCALAR) {
+ *PL_markstack_ptr = PL_stack_sp - PL_stack_base;
+ PL_stack_sp += items;
+ } else {
+ *PL_markstack_ptr = PL_stack_sp - PL_stack_base - items;
+ }
+
+ SU_D({
+ PerlIO_printf(Perl_debug_log,
+ "%p: cx=%d gimme=%s items=%d sp=%d oldmark=%d mark=%d\n",
+ ud, cxix,
+ gimme == G_VOID ? "void" : gimme == G_ARRAY ? "list" : "scalar",
+ items, PL_stack_sp - PL_stack_base, *PL_markstack_ptr, mark);
+ });
+
+ PL_op = PL_ppaddr[OP_RETURN](aTHX);
+ *PL_markstack_ptr = mark;
+
+ fakeop.op_next = PL_op;
+ PL_op = &fakeop;
+
+ Safefree(ud);
+}
+
+/* --- XS ------------------------------------------------------------------ */
+
#define SU_GET_LEVEL(A) \
if (items > A) { \
SV *lsv = ST(A); \
if (level > cxstack_ix) \
level = cxstack_ix;
-/* --- XS ------------------------------------------------------------------ */
+#define SU_DOPOPTOCX(t) \
+ STMT_START { \
+ I32 i, cxix = cxstack_ix, from = 0; \
+ if (items) \
+ from = SvIV(ST(0)); \
+ for (i = cxix - from; i >= 0; --i) { \
+ if (CxTYPE(&cxstack[i]) == t) { \
+ ST(0) = sv_2mortal(newSViv(cxix - i)); \
+ XSRETURN(1); \
+ } \
+ } \
+ XSRETURN_UNDEF; \
+ } STMT_END
+
+XS(XS_Scope__Upper_unwind); /* prototype to pass -Wmissing-prototypes */
+
+XS(XS_Scope__Upper_unwind) {
+#ifdef dVAR
+ dVAR; dXSARGS;
+#else
+ dXSARGS;
+#endif
+ I32 from = 0, cxix = cxstack_ix;
+ su_ud_unwind *ud;
+ SV *level;
+ PERL_UNUSED_VAR(cv); /* -W */
+ PERL_UNUSED_VAR(ax); /* -Wall */
+ if (items) {
+ from = SvIV(ST(items - 1));
+ if (from < 0)
+ from = 0;
+ else if (from > cxix)
+ from = cxix;
+ }
+ cxix -= from;
+ do {
+ PERL_CONTEXT *cx = cxstack + cxix;
+ switch (CxTYPE(cx)) {
+ case CXt_SUB:
+ case CXt_EVAL:
+ case CXt_FORMAT:
+ /* pp_entersub will try to sanitize the stack - screw that, we're insane */
+ if (GIMME_V == G_SCALAR)
+ PL_stack_sp = PL_stack_base + TOPMARK + 1;
+ Newx(ud, 1, su_ud_unwind);
+ ud->cxix = cxix;
+ ud->items = items;
+ SAVEDESTRUCTOR_X(su_unwind, ud);
+ return;
+ default:
+ break;
+ }
+ } while (--cxix >= 0);
+ croak("Can't return outside a subroutine");
+}
MODULE = Scope::Upper PACKAGE = Scope::Upper
PROTOTYPES: ENABLE
+BOOT:
+{
+ HV *stash = gv_stashpv(__PACKAGE__, 1);
+ newCONSTSUB(stash, "HERE", newSViv(0));
+ newXSproto("Scope::Upper::unwind", XS_Scope__Upper_unwind, file, NULL);
+}
+
SV *
-TOPLEVEL()
+TOP()
PROTOTYPE:
CODE:
RETVAL = newSViv(cxstack_ix);
OUTPUT:
RETVAL
+SV *
+UP(...)
+PROTOTYPE: ;$
+PREINIT:
+ I32 i = 0;
+ I32 cxix = cxstack_ix;
+CODE:
+ if (items)
+ i = SvIV(ST(0));
+ if (++i > cxix)
+ i = cxix;
+ RETVAL = newSViv(i);
+OUTPUT:
+ RETVAL
+
+SV *
+DOWN(...)
+PROTOTYPE: ;$
+PREINIT:
+ I32 i = 0;
+CODE:
+ if (items)
+ i = SvIV(ST(0));
+ if (--i < 0)
+ i = 0;
+ RETVAL = newSViv(i);
+OUTPUT:
+ RETVAL
+
+void
+SUB(...)
+PROTOTYPE: ;$
+PPCODE:
+ SU_DOPOPTOCX(CXt_SUB);
+
+void
+EVAL(...)
+PROTOTYPE: ;$
+PPCODE:
+ SU_DOPOPTOCX(CXt_EVAL);
+
void
reap(SV *hook, ...)
PROTOTYPE: &;$