Correct the citation for Peter McIlroy's sorting paper.

[perl5.git] / pp_sort.c

diff --git a/pp_sort.c b/pp_sort.c
index d6a5e88..1bb0cd8 100644 (file)
--- a/pp_sort.c
+++ b/pp_sort.c
@@ -53,9 +53,12 @@
  * The original code was written in conjunction with BSD Computer Software
  * Research Group at University of California, Berkeley.
  *
- * See also: "Optimistic Merge Sort" (SODA '92)
+ * See also: "Optimistic Sorting and Information Theoretic Complexity"
+ *           Peter McIlroy
+ *           SODA (Fourth Annual ACM-SIAM Symposium on Discrete Algorithms),
+ *           pp 467-474, Austin, Texas, 25-27 January 1993.
  *
- * The integration to Perl is by John P. Linderman <jpl@research.att.com>.
+ * The integration to Perl is by John P. Linderman <jpl.jpl@gmail.com>.
  *
  * The code can be distributed under the same terms as Perl itself.
  *
@@ -1432,7 +1435,7 @@ S_qsortsv(pTHX_ gptr *list1, size_t nmemb, SVCOMPARE_t cmp, U32 flags)
 
 Sort an array. Here is an example:
 
-    sortsv(AvARRAY(av), av_len(av)+1, Perl_sv_cmp_locale);
+    sortsv(AvARRAY(av), av_top_index(av)+1, Perl_sv_cmp_locale);
 
 Currently this always uses mergesort. See sortsv_flags for a more
 flexible routine.
@@ -1474,7 +1477,7 @@ PP(pp_sort)
 {
     dVAR; dSP; dMARK; dORIGMARK;
     SV **p1 = ORIGMARK+1, **p2;
-    I32 max, i;
+    SSize_t max, i;
     AV* av = NULL;
     HV *stash;
     GV *gv;
@@ -1483,6 +1486,7 @@ PP(pp_sort)
     OP* const nextop = PL_op->op_next;
     I32 overloading = 0;
     bool hasargs = FALSE;
+    bool copytmps;
     I32 is_xsub = 0;
     I32 sorting_av = 0;
     const U8 priv = PL_op->op_private;
@@ -1588,7 +1592,10 @@ PP(pp_sort)
            if (SvREADONLY(av))
                Perl_croak_no_modify();
            else
+           {
                SvREADONLY_on(av);
+               save_pushptr((void *)av, SAVEt_READONLY_OFF);
+           }
            p1 = p2 = AvARRAY(av);
            sorting_av = 1;
        }
@@ -1601,8 +1608,11 @@ PP(pp_sort)
     /* shuffle stack down, removing optional initial cv (p1!=p2), plus
      * any nulls; also stringify or converting to integer or number as
      * required any args */
+    copytmps = !sorting_av && PL_sortcop;
     for (i=max; i > 0 ; i--) {
        if ((*p1 = *p2++)) {                    /* Weed out nulls. */
+           if (copytmps && SvPADTMP(*p1) && !IS_PADGV(*p1))
+               *p1 = sv_mortalcopy(*p1);
            SvTEMP_off(*p1);
            if (!PL_sortcop) {
                if (priv & OPpSORT_NUMERIC) {
@@ -1648,10 +1658,8 @@ PP(pp_sort)
            if (!hasargs && !is_xsub) {
                SAVESPTR(PL_firstgv);
                SAVESPTR(PL_secondgv);
-               SAVESPTR(PL_sortstash);
                PL_firstgv = gv_fetchpvs("a", GV_ADD|GV_NOTQUAL, SVt_PV);
                PL_secondgv = gv_fetchpvs("b", GV_ADD|GV_NOTQUAL, SVt_PV);
-               PL_sortstash = stash;
                SAVESPTR(GvSV(PL_firstgv));
                SAVESPTR(GvSV(PL_secondgv));
            }