don't allocate when parsing unknown keywords

diff --git a/Parameters.xs b/Parameters.xs
index 282bb03..fa8e4ee 100644 (file)
--- a/Parameters.xs
+++ b/Parameters.xs
@@ -157,67 +157,6 @@ static SV *sentinel_mortalize(Sentinel sen, SV *sv) {
        return sv;
 }
 
-static int kw_flags(pTHX_ Sentinel sen, const char *kw_ptr, STRLEN kw_len, KWSpec *spec) {
-       HV *hints;
-       SV *sv, **psv;
-       const char *p, *kw_active;
-       STRLEN kw_active_len;
-
-       spec->flags = 0;
-       spec->shift = sentinel_mortalize(sen, newSVpvs(""));
-       spec->attrs = sentinel_mortalize(sen, newSVpvs(""));
-
-       if (!(hints = GvHV(PL_hintgv))) {
-               return FALSE;
-       }
-       if (!(psv = hv_fetchs(hints, HINTK_KEYWORDS, 0))) {
-               return FALSE;
-       }
-       sv = *psv;
-       kw_active = SvPV(sv, kw_active_len);
-       if (kw_active_len <= kw_len) {
-               return FALSE;
-       }
-       for (
-               p = kw_active;
-               (p = strchr(p, *kw_ptr)) &&
-               p < kw_active + kw_active_len - kw_len;
-               p++
-       ) {
-               if (
-                       (p == kw_active || p[-1] == ' ') &&
-                       p[kw_len] == ' ' &&
-                       memcmp(kw_ptr, p, kw_len) == 0
-               ) {
-
-#define FETCH_HINTK_INTO(NAME, PTR, LEN, X) STMT_START { \
-       const char *fk_ptr_; \
-       STRLEN fk_len_; \
-       SV *fk_sv_; \
-       fk_sv_ = sentinel_mortalize(sen, newSVpvs(HINTK_ ## NAME)); \
-       sv_catpvn(fk_sv_, PTR, LEN); \
-       fk_ptr_ = SvPV(fk_sv_, fk_len_); \
-       if (!((X) = hv_fetch(hints, fk_ptr_, fk_len_, 0))) { \
-               croak("%s: internal error: $^H{'%.*s'} not set", MY_PKG, (int)fk_len_, fk_ptr_); \
-       } \
-} STMT_END
-
-                       FETCH_HINTK_INTO(FLAGS_, kw_ptr, kw_len, psv);
-                       spec->flags = SvIV(*psv);
-
-                       FETCH_HINTK_INTO(SHIFT_, kw_ptr, kw_len, psv);
-                       SvSetSV(spec->shift, *psv);
-
-                       FETCH_HINTK_INTO(ATTRS_, kw_ptr, kw_len, psv);
-                       SvSetSV(spec->attrs, *psv);
-
-#undef FETCH_HINTK_INTO
-                       return TRUE;
-               }
-       }
-       return FALSE;
-}
-
 
 #if HAVE_PERL_VERSION(5, 17, 2)
  #define MY_OP_SLABBED(O) ((O)->op_slabbed)
@@ -2003,25 +1942,86 @@ static int parse_fun(pTHX_ Sentinel sen, OP **pop, const char *keyword_ptr, STRL
        }
 }
 
+static int kw_flags_enter(pTHX_ Sentinel sen, const char *kw_ptr, STRLEN kw_len, KWSpec *spec) {
+       HV *hints;
+       SV *sv, **psv;
+       const char *p, *kw_active;
+       STRLEN kw_active_len;
+
+       if (!(hints = GvHV(PL_hintgv))) {
+               return FALSE;
+       }
+       if (!(psv = hv_fetchs(hints, HINTK_KEYWORDS, 0))) {
+               return FALSE;
+       }
+       sv = *psv;
+       kw_active = SvPV(sv, kw_active_len);
+       if (kw_active_len <= kw_len) {
+               return FALSE;
+       }
+       for (
+               p = kw_active;
+               (p = strchr(p, *kw_ptr)) &&
+               p < kw_active + kw_active_len - kw_len;
+               p++
+       ) {
+               if (
+                       (p == kw_active || p[-1] == ' ') &&
+                       p[kw_len] == ' ' &&
+                       memcmp(kw_ptr, p, kw_len) == 0
+               ) {
+                       ENTER;
+                       SAVETMPS;
+
+                       SAVEDESTRUCTOR_X(sentinel_clear_void, sen);
+
+                       spec->flags = 0;
+                       spec->shift = sentinel_mortalize(sen, newSVpvs(""));
+                       spec->attrs = sentinel_mortalize(sen, newSVpvs(""));
+
+#define FETCH_HINTK_INTO(NAME, PTR, LEN, X) STMT_START { \
+       const char *fk_ptr_; \
+       STRLEN fk_len_; \
+       SV *fk_sv_; \
+       fk_sv_ = sentinel_mortalize(sen, newSVpvs(HINTK_ ## NAME)); \
+       sv_catpvn(fk_sv_, PTR, LEN); \
+       fk_ptr_ = SvPV(fk_sv_, fk_len_); \
+       if (!((X) = hv_fetch(hints, fk_ptr_, fk_len_, 0))) { \
+               croak("%s: internal error: $^H{'%.*s'} not set", MY_PKG, (int)fk_len_, fk_ptr_); \
+       } \
+} STMT_END
+
+                       FETCH_HINTK_INTO(FLAGS_, kw_ptr, kw_len, psv);
+                       spec->flags = SvIV(*psv);
+
+                       FETCH_HINTK_INTO(SHIFT_, kw_ptr, kw_len, psv);
+                       SvSetSV(spec->shift, *psv);
+
+                       FETCH_HINTK_INTO(ATTRS_, kw_ptr, kw_len, psv);
+                       SvSetSV(spec->attrs, *psv);
+
+#undef FETCH_HINTK_INTO
+                       return TRUE;
+               }
+       }
+       return FALSE;
+}
+
 static int my_keyword_plugin(pTHX_ char *keyword_ptr, STRLEN keyword_len, OP **op_ptr) {
+       Sentinel sen = { NULL };
        KWSpec spec;
        int ret;
-       Sentinel sen = { NULL };
 
-       ENTER;
-       SAVETMPS;
-
-       SAVEDESTRUCTOR_X(sentinel_clear_void, sen);
-
-       if (kw_flags(aTHX_ sen, keyword_ptr, keyword_len, &spec)) {
+       if (kw_flags_enter(aTHX_ sen, keyword_ptr, keyword_len, &spec)) {
+               /* scope was entered, 'sen' and 'spec' are initialized */
                ret = parse_fun(aTHX_ sen, op_ptr, keyword_ptr, keyword_len, &spec);
+               FREETMPS;
+               LEAVE;
        } else {
+               /* not one of our keywords, no allocation done */
                ret = next_keyword_plugin(aTHX_ keyword_ptr, keyword_len, op_ptr);
        }
 
-       FREETMPS;
-       LEAVE;
-
        return ret;
 }