(Version 2) Extending unpack to deal with counted strings

[p5sagit/p5-mst-13.2.git] / pp.c

diff --git a/pp.c b/pp.c
index c7fd585..69d3795 100644 (file)
--- a/pp.c
+++ b/pp.c
@@ -900,7 +900,7 @@ PP(pp_postinc)
 PP(pp_postdec)
 {
     djSP; dTARGET;
-    if(SvREADONLY(TOPs) || SvTYPE(TOPs) > SVt_PVLV)
+    if (SvREADONLY(TOPs) || SvTYPE(TOPs) > SVt_PVLV)
        Perl_croak(aTHX_ PL_no_modify);
     sv_setsv(TARG, TOPs);
     if (SvIOK_notUV(TOPs) && !SvNOK(TOPs) && !SvPOK(TOPs) &&
@@ -3386,6 +3386,18 @@ PP(pp_unpack)
                DIE(aTHX_ "x outside of string");
            s += len;
            break;
+       case '#':
+           if (oldsp >= SP)
+               DIE(aTHX_ "# must follow a numeric type");
+           if (*pat != 'a' && *pat != 'A' && *pat != 'Z')
+               DIE(aTHX_ "# must be followed by a, A or Z");
+           datumtype = *pat++;
+           if (*pat == '*')
+               pat++;          /* ignore '*' for compatibility with pack */
+           if (isDIGIT(*pat))
+               DIE(aTHX_ "# cannot take a count" );
+           len = POPi;
+           /* drop through */
        case 'A':
        case 'Z':
        case 'a':
@@ -4356,7 +4368,8 @@ PP(pp_pack)
     MARK++;
     sv_setpvn(cat, "", 0);
     while (pat < patend) {
-#define NEXTFROM (items-- > 0 ? *MARK++ : &PL_sv_no)
+       SV *lengthcode = Nullsv;
+#define NEXTFROM ( lengthcode ? lengthcode : items-- > 0 ? *MARK++ : &PL_sv_no)
        datumtype = *pat++ & 0xFF;
 #ifdef PERL_NATINT_PACK
        natint = 0;
@@ -4386,12 +4399,20 @@ PP(pp_pack)
        }
        else
            len = 1;
+       if (*pat == '#') {
+           ++pat;
+           if (*pat != 'a' && *pat != 'A' && *pat != 'Z' || pat[1] != '*')
+               DIE(aTHX_ "# must be followed by a*, A* or Z*");
+           lengthcode = sv_2mortal(newSViv(sv_len(items > 0
+                                                  ? *MARK : &PL_sv_no)));
+       }
        switch(datumtype) {
        default:
            Perl_croak(aTHX_ "Invalid type in pack: '%c'", (int)datumtype);
        case ',': /* grandfather in commas but with a warning */
            if (commas++ == 0 && ckWARN(WARN_UNSAFE))
-               Perl_warner(aTHX_ WARN_UNSAFE, "Invalid type in pack: '%c'", (int)datumtype);
+               Perl_warner(aTHX_ WARN_UNSAFE,
+                           "Invalid type in pack: '%c'", (int)datumtype);
            break;
        case '%':
            DIE(aTHX_ "%% may only be used in unpack");