#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;
}
-#define SU_GET_LEVEL(A) \
- if (items > A) { \
- SV *lsv = ST(A); \
- if (SvOK(lsv)) \
- level = SvUV(lsv); \
- if (level < 0) \
- XSRETURN(0); \
- } \
- if (level > cxstack_ix) \
- level = cxstack_ix;
+/* --- 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) \
+ STMT_START { \
+ if (items > A) { \
+ SV *lsv = ST(A); \
+ if (SvOK(lsv)) \
+ level = SvIV(lsv); \
+ if (level < 0) \
+ XSRETURN(0); \
+ } \
+ if (level > cxstack_ix) \
+ level = cxstack_ix; \
+ } STMT_END
+
+#define SU_GET_CONTEXT(A, B) \
+ STMT_START { \
+ if (items > A) { \
+ SV *lsv = ST(B); \
+ if (SvOK(lsv)) \
+ level = SvIV(lsv); \
+ if (level < 0) \
+ level = 0; \
+ else if (level > cxix) \
+ level = cxix; \
+ } \
+ } STMT_END
+
+#define SU_DOPOPTOCX(t) \
+ STMT_START { \
+ I32 i, cxix = cxstack_ix, level = 0; \
+ SU_GET_CONTEXT(0, 0); \
+ for (i = cxix - level; 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 cxix = cxstack_ix, level = 0;
+ su_ud_unwind *ud;
+
+ PERL_UNUSED_VAR(cv); /* -W */
+ PERL_UNUSED_VAR(ax); /* -Wall */
+
+ SU_GET_CONTEXT(0, items - 1);
+ cxix -= level;
+ 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
+CALLER(...)
+PROTOTYPE: ;$
+PREINIT:
+ I32 cxix = cxstack_ix, caller = 0, level = 0;
+PPCODE:
+ if (items) {
+ SV *csv = ST(0);
+ if (SvOK(csv))
+ caller = SvIV(csv);
+ }
+ cxix = cxstack_ix;
+ while (cxix > 0) {
+ PERL_CONTEXT *cx = cxstack + cxix--;
+ switch (CxTYPE(cx)) {
+ case CXt_SUB:
+ case CXt_EVAL:
+ case CXt_FORMAT:
+ --caller;
+ if (caller < 0)
+ goto done;
+ break;
+ }
+ ++level;
+ }
+done:
+ ST(0) = sv_2mortal(newSViv(level));
+ XSRETURN(1);
+
+void
+want_at(...)
+PROTOTYPE: ;$
+PREINIT:
+ I32 cxix = cxstack_ix, level = 0;
+PPCODE:
+ SU_GET_CONTEXT(0, 0);
+ cxix -= level;
+ while (cxix > 0) {
+ PERL_CONTEXT *cx = cxstack + cxix--;
+ switch (CxTYPE(cx)) {
+ case CXt_SUB:
+ case CXt_EVAL:
+ case CXt_FORMAT: {
+ I32 gimme = cx->blk_gimme;
+ switch (gimme) {
+ case G_VOID: XSRETURN_UNDEF; break;
+ case G_SCALAR: XSRETURN_NO; break;
+ case G_ARRAY: XSRETURN_YES; break;
+ }
+ break;
+ }
+ }
+ }
+ XSRETURN_UNDEF;
+
void
reap(SV *hook, ...)
PROTOTYPE: &;$