+/* This file is part of the Scope::Upper Perl module.
+ * See http://search.cpan.org/dist/Scope-Upper/ */
+
+#define PERL_NO_GET_CONTEXT
+#include "EXTERN.h"
+#include "perl.h"
+#include "XSUB.h"
+
+#ifndef SU_DEBUG
+# define SU_DEBUG 0
+#endif
+
+#ifndef STMT_START
+# define STMT_START do
+#endif
+
+#ifndef STMT_END
+# define STMT_END while (0)
+#endif
+
+#if SU_DEBUG
+# define SU_D(X) STMT_START X STMT_END
+#else
+# define SU_D(X)
+#endif
+
+#ifndef SvPV_const
+# define SvPV_const(S, L) SvPV(S, L)
+#endif
+
+#ifndef SvPV_nolen_const
+# define SvPV_nolen_const(S) SvPV_nolen(S)
+#endif
+
+#ifndef HvNAME_get
+# define HvNAME_get(H) HvNAME(H)
+#endif
+
+#ifndef gv_fetchpvn_flags
+# define gv_fetchpvn_flags(A, B, C, D) gv_fetchpv((A), (C), (D))
+#endif
+
+#define SU_HAS_PERL(R, V, S) (PERL_REVISION > (R) || (PERL_REVISION == (R) && (PERL_VERSION > (V) || (PERL_VERSION == (V) && (PERL_SUBVERSION >= (S))))))
+
+typedef struct {
+ I32 depth;
+ I32 *origin;
+ void (*handler)(pTHX_ void *);
+} su_ud_common;
+
+#define SU_UD_DEPTH(U) (((su_ud_common *) (U))->depth)
+#define SU_UD_ORIGIN(U) (((su_ud_common *) (U))->origin)
+#define SU_UD_HANDLER(U) (((su_ud_common *) (U))->handler)
+
+#define SU_UD_FREE(U) do { \
+ if (SU_UD_ORIGIN(U)) Safefree(SU_UD_ORIGIN(U)); \
+ Safefree(U); \
+} while (0)
+
+typedef struct {
+ su_ud_common ci;
+ SV *cb;
+} su_ud_reap;
+
+STATIC void su_call(pTHX_ void *ud_) {
+ su_ud_reap *ud = (su_ud_reap *) ud_;
+#if SU_HAS_PERL(5, 10, 0)
+ I32 dieing = PL_op->op_type == OP_DIE;
+#endif
+
+ dSP;
+
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: @@@ call at %d (save is %d)\n",
+ ud, PL_scopestack_ix, PL_savestack_ix));
+ ENTER;
+ SAVETMPS;
+
+ PUSHMARK(SP);
+ PUTBACK;
+
+ /* If cxstack_ix isn't incremented there, the eval context will be overwritten
+ * when the new sub scope will be created in call_sv. */
+
+#if SU_HAS_PERL(5, 10, 0)
+ if (dieing)
+ if (cxstack_ix < cxstack_max)
+ ++cxstack_ix;
+ else
+ cxstack_ix = Perl_cxinc(aTHX);
+#endif
+
+ call_sv(ud->cb, G_VOID);
+
+#if SU_HAS_PERL(5, 10, 0)
+ if (dieing && cxstack_ix > 0)
+ --cxstack_ix;
+#endif
+
+ SPAGAIN;
+ PUTBACK;
+
+ FREETMPS;
+ LEAVE;
+
+ SvREFCNT_dec(ud->cb);
+ SU_UD_FREE(ud);
+}
+
+STATIC void su_reap(pTHX_ void *ud) {
+#define su_reap(U) su_reap(aTHX_ (U))
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: === reap at %d (save is %d)\n",
+ ud, PL_scopestack_ix, PL_savestack_ix));
+ SAVEDESTRUCTOR_X(su_call, ud);
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: savestack is now at %d, base at %d\n",
+ ud, PL_savestack_ix,
+ PL_scopestack[PL_scopestack_ix]));
+}
+
+typedef struct {
+ su_ud_common ci;
+ SV *sv;
+ SV *val;
+ SV *elem;
+} su_ud_localize;
+
+/* Those two functions are courtesy of pp_hot.c:pp_helem */
+
+STATIC I32 su_hv_preeminent(pTHX_ HV *hv, SV *keysv) {
+#define su_hv_preeminent(H, K) su_hv_preeminent(aTHX_ (H), (K))
+ MAGIC *mg;
+ HV *stash;
+ return (!SvRMAGICAL(hv)
+ || mg_find((SV *) hv, PERL_MAGIC_env)
+ || ((mg = mg_find((SV *) hv, PERL_MAGIC_tied))
+ /* Try to preserve the existenceness of a tied hash
+ * element by using EXISTS and DELETE if possible.
+ * Fallback to FETCH and STORE otherwise */
+ && (stash = SvSTASH(SvRV(SvTIED_obj((SV *) hv, mg))))
+ && gv_fetchmethod_autoload(stash, "EXISTS", TRUE)
+ && gv_fetchmethod_autoload(stash, "DELETE", TRUE)
+ )
+ ) ? hv_exists_ent(hv, keysv, 0) : 1;
+}
+
+STATIC void su_save_helem(pTHX_ HV *hv, SV *keysv, SV **svp, I32 preeminent) {
+#define su_save_helem(H, K, S, P) su_save_helem(aTHX_ (H), (K), (S), (P))
+ if (HvNAME_get(hv) && isGV(*svp)) {
+ save_gp((GV *) *svp, 0);
+ return;
+ }
+ if (!preeminent) {
+ STRLEN keylen;
+ const char * const key = SvPV_const(keysv, keylen);
+ SAVEDELETE(hv, savepvn(key, keylen),
+ SvUTF8(keysv) ? -(I32)keylen : (I32)keylen);
+ } else {
+ save_helem(hv, keysv, svp);
+ }
+}
+
+STATIC void su_localize(pTHX_ void *ud_) {
+#define su_localize(U) su_localize(aTHX_ (U))
+ su_ud_localize *ud = (su_ud_localize *) ud_;
+ SV *sv = ud->sv;
+ SV *val = ud->val;
+ SV *elem = ud->elem;
+ GV *gv;
+ UV deref = 0;
+ svtype t = SVt_NULL;
+
+ if (SvTYPE(sv) >= SVt_PVGV) {
+ gv = (GV *) sv;
+ if (!SvROK(val))
+ goto assign;
+ t = SvTYPE(SvRV(val));
+ deref = 1;
+ } else {
+ STRLEN len, l;
+ const char *p = SvPV_const(sv, len), *s;
+ for (s = p, l = len; l > 0 && isSPACE(*s); ++s, --l) { }
+ if (!l) {
+ l = len;
+ s = p;
+ }
+ switch (*s) {
+ case '$': t = SVt_PV; break;
+ case '@': t = SVt_PVAV; break;
+ case '%': t = SVt_PVHV; break;
+ case '&': t = SVt_PVCV; break;
+ case '*': t = SVt_PVGV; break;
+ }
+ if (t == SVt_NULL) {
+ if (SvROK(val) && !sv_isobject(val)) {
+ t = SvTYPE(SvRV(val));
+ deref = 1;
+ } else {
+ t = SvTYPE(val);
+ }
+ } else {
+ ++s;
+ --l;
+ }
+ gv = gv_fetchpvn_flags(s, l, GV_ADDMULTI, SVt_PVGV);
+ }
+
+ SU_D({
+ SV *z = newSV_type(t);
+ PerlIO_printf(Perl_debug_log, "%p: === localize a %s at %d (save is %d)\n",
+ ud, sv_reftype(z, 0),
+ PL_scopestack_ix, PL_savestack_ix);
+ SvREFCNT_dec(z);
+ });
+
+ /* Inspired from Alias.pm */
+ switch (t) {
+ case SVt_PVAV:
+ if (elem) {
+ I32 idx = SvIV(elem);
+ AV *av = GvAV(gv);
+ SV **svp = av_fetch(av, idx, 1);
+ if (!*svp || *svp == &PL_sv_undef) croak(PL_no_aelem, idx);
+ save_aelem(av, idx, svp);
+ gv = (GV *) *svp;
+ goto maybe_deref;
+ } else
+ save_ary(gv);
+ break;
+ case SVt_PVHV:
+ if (elem) {
+ HV *hv = GvHV(gv);
+ I32 preeminent = hv ? su_hv_preeminent(hv, elem) : 0;
+ HE *he = hv_fetch_ent(hv, elem, 1, 0);
+ SV **svp = he ? &HeVAL(he) : NULL;
+ if (!svp || *svp == &PL_sv_undef) croak("Modification of non-creatable hash value attempted, subscript \"%s\"", SvPV_nolen_const(*svp));
+ su_save_helem(hv, elem, svp, preeminent);
+ gv = (GV *) *svp;
+ goto maybe_deref;
+ } else
+ save_hash(gv);
+ break;
+ case SVt_PVGV:
+ save_gp(gv, 1); /* hide previous entry in symtab */
+ break;
+ case SVt_PVCV:
+ SAVESPTR(GvCV(gv));
+ GvCV(gv) = NULL;
+ break;
+ default:
+ gv = (GV *) save_scalar(gv);
+maybe_deref:
+ if (deref)
+ val = SvRV(val);
+ break;
+ }
+
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: savestack is now at %d, base at %d\n",
+ ud, PL_savestack_ix,
+ PL_scopestack[PL_scopestack_ix]));
+
+assign:
+ SvSetMagicSV((SV *) gv, val);
+
+ SvREFCNT_dec(ud->elem);
+ SvREFCNT_dec(ud->val);
+ SvREFCNT_dec(ud->sv);
+ SU_UD_FREE(ud);
+}
+
+#if SU_DEBUG
+# ifdef DEBUGGING
+# define SU_CXNAME PL_block_type[CxTYPE(&cxstack[cxstack_ix])]
+# else
+# define SU_CXNAME "XXX"
+# endif
+#endif
+
+STATIC void su_pop(pTHX_ void *ud) {
+#define su_pop(U) su_pop(aTHX_ (U))
+ I32 depth, base, mark, *origin;
+ depth = SU_UD_DEPTH(ud);
+
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: --- pop %s at %d from %d to %d [%d]\n",
+ ud, SU_CXNAME,
+ PL_scopestack_ix, PL_savestack_ix,
+ PL_scopestack[PL_scopestack_ix],
+ depth));
+
+ origin = SU_UD_ORIGIN(ud);
+ mark = origin[depth];
+ base = origin[depth - 1];
+
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: clean from %d down to %d\n",
+ ud, mark, base));
+
+ if (base < mark) {
+ PL_savestack_ix = mark;
+ leave_scope(base);
+ }
+ PL_savestack_ix = base;
+ if (--depth > 0) {
+ SU_UD_DEPTH(ud) = depth;
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: save new destructor at %d [%d]\n",
+ ud, PL_savestack_ix, depth));
+ SAVEDESTRUCTOR_X(su_pop, ud);
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: pop end at at %d [%d]\n",
+ ud, PL_savestack_ix, depth));
+ } else {
+ SU_UD_HANDLER(ud)(aTHX_ ud);
+ }
+}
+
+STATIC I32 su_init(pTHX_ I32 level, void *ud, I32 size) {
+#define su_init(L, U, S) su_init(aTHX_ (L), (U), (S))
+ I32 i, depth = 0, *origin;
+ I32 cur, last, step;
+
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: ### init for level %d\n", ud, level));
+
+ for (i = 0; i < level; ++i) {
+ PERL_CONTEXT *cx = &cxstack[cxstack_ix - i];
+ switch (CxTYPE(cx)) {
+#if SU_HAS_PERL(5, 11, 0)
+ case CXt_LOOP_FOR:
+ case CXt_LOOP_PLAIN:
+ case CXt_LOOP_LAZYSV:
+ case CXt_LOOP_LAZYIV:
+#else
+ case CXt_LOOP:
+#endif
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: cx %d is loop\n", ud, i));
+ depth += 2;
+ break;
+ default:
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: cx %d is normal\n", ud, i));
+ depth++;
+ break;
+ }
+ }
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: depth is %d\n", ud, depth));
+
+ Newx(origin, depth + 1, I32);
+ origin[0] = PL_scopestack[PL_scopestack_ix - depth];
+ PL_scopestack[PL_scopestack_ix - depth] += size;
+ for (i = depth - 1; i >= 1; --i) {
+ I32 j = PL_scopestack_ix - i;
+ origin[depth - i] = PL_scopestack[j];
+ PL_scopestack[j] += 3;
+ }
+ origin[depth] = PL_savestack_ix;
+
+ SU_D({
+ PerlIO_printf(Perl_debug_log, "%p: d=%d s=%d x=%d c=%d o=%d\n", ud,
+ depth, 0, PL_scopestack_ix - 1, PL_savestack_ix, origin[depth]);
+ for (i = depth - 1; i >= 0; --i) {
+ I32 x = PL_scopestack_ix - depth + i;
+ PerlIO_printf(Perl_debug_log, "%p: d=%d s=%d x=%d c=%d o=%d\n", ud,
+ i, depth - i, x, PL_scopestack[x], origin[i]);
+ }
+ });
+
+ SU_UD_ORIGIN(ud) = origin;
+ SU_UD_DEPTH(ud) = depth;
+ 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;
+
+/* --- XS ------------------------------------------------------------------ */
+
+MODULE = Scope::Upper PACKAGE = Scope::Upper
+
+PROTOTYPES: ENABLE
+
+SV *
+TOPLEVEL()
+PROTOTYPE:
+CODE:
+ RETVAL = newSViv(cxstack_ix);
+OUTPUT:
+ RETVAL
+
+void
+reap(SV *hook, ...)
+PROTOTYPE: &;$
+PREINIT:
+ I32 level = 0;
+ su_ud_reap *ud;
+CODE:
+ SU_GET_LEVEL(1);
+ Newx(ud, 1, su_ud_reap);
+ SU_UD_ORIGIN(ud) = NULL;
+ SU_UD_HANDLER(ud) = su_reap;
+ ud->cb = newSVsv(hook);
+ LEAVE;
+ if (level) {
+ I32 depth = su_init(level, ud, 3);
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: set original destructor at %d [%d]\n",
+ ud, PL_savestack_ix, depth));
+ SAVEDESTRUCTOR_X(su_pop, ud);
+ } else
+ su_reap(ud);
+ ENTER;
+
+void
+localize(SV *sv, SV *val, ...)
+PROTOTYPE: $$;$
+PREINIT:
+ I32 level = 0;
+ su_ud_localize *ud;
+CODE:
+ SU_GET_LEVEL(2);
+ Newx(ud, 1, su_ud_localize);
+ SU_UD_ORIGIN(ud) = NULL;
+ SU_UD_HANDLER(ud) = su_localize;
+ SvREFCNT_inc(sv);
+ ud->sv = sv;
+ ud->val = newSVsv(val);
+ ud->elem = NULL;
+ LEAVE;
+ if (level) {
+ I32 depth = su_init(level, ud, 3);
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: set original destructor at %d [%d]\n",
+ ud, PL_savestack_ix, depth));
+ SAVEDESTRUCTOR_X(su_pop, ud);
+ } else
+ su_localize(ud);
+ ENTER;
+
+void
+localize_elem(SV *sv, SV *elem, SV *val, ...)
+PROTOTYPE: $$$;$
+PREINIT:
+ I32 level = 0;
+ su_ud_localize *ud;
+CODE:
+ SU_GET_LEVEL(3);
+ Newx(ud, 1, su_ud_localize);
+ SU_UD_ORIGIN(ud) = NULL;
+ SU_UD_HANDLER(ud) = su_localize;
+ SvREFCNT_inc(sv);
+ ud->sv = sv;
+ ud->val = newSVsv(val);
+ SvREFCNT_inc(elem);
+ ud->elem = elem;
+ LEAVE;
+ if (level) {
+ I32 depth = su_init(level, ud, 4);
+ SU_D(PerlIO_printf(Perl_debug_log, "%p: set original destructor at %d [%d]\n",
+ ud, PL_savestack_ix, depth));
+ SAVEDESTRUCTOR_X(su_pop, ud);
+ } else
+ su_localize(ud);
+ ENTER;
+