-
- assert(SvTYPE(littlestr) == SVt_PVGV);
- assert(SvVALID(littlestr));
-
- if (*old_posp == -1
- ? (pos = PL_screamfirst[BmRARE(littlestr)]) < 0
- : (((pos = *old_posp), pos += PL_screamnext[pos]) == 0)) {
- cant_find:
- if ( BmRARE(littlestr) == '\n'
- && BmPREVIOUS(littlestr) == SvCUR(littlestr) - 1) {
- little = (const unsigned char *)(SvPVX_const(littlestr));
- littleend = little + SvCUR(littlestr);
- first = *little++;
- goto check_tail;
- }
- return NULL;
- }
-
- little = (const unsigned char *)(SvPVX_const(littlestr));
- littleend = little + SvCUR(littlestr);
- first = *little++;
- /* The value of pos we can start at: */
- previous = BmPREVIOUS(littlestr);
- big = (const unsigned char *)(SvPVX_const(bigstr));
- /* The value of pos we can stop at: */
- stop_pos = SvCUR(bigstr) - end_shift - (SvCUR(littlestr) - 1 - previous);
- if (previous + start_shift > stop_pos) {
-/*
- stop_pos does not include SvTAIL in the count, so this check is incorrect
- (I think) - see [ID 20010618.006] and t/op/study.t. HVDS 2001/06/19
-*/
-#if 0
- if (previous + start_shift == stop_pos + 1) /* A fake '\n'? */
- goto check_tail;
-#endif
- return NULL;
- }
- while (pos < previous + start_shift) {
- if (!(pos += PL_screamnext[pos]))
- goto cant_find;
- }
- big -= previous;
- do {
- register const unsigned char *s, *x;
- if (pos >= stop_pos) break;
- if (big[pos] != first)
- continue;
- for (x=big+pos+1,s=little; s < littleend; /**/ ) {
- if (*s++ != *x++) {
- s--;
- break;
- }
- }
- if (s == littleend) {
- *old_posp = pos;
- if (!last) return (char *)(big+pos);
- found = 1;
- }
- } while ( pos += PL_screamnext[pos] );
- if (last && found)
- return (char *)(big+(*old_posp));
- check_tail:
- if (!SvTAIL(littlestr) || (end_shift > 0))
- return NULL;
- /* Ignore the trailing "\n". This code is not microoptimized */
- big = (const unsigned char *)(SvPVX_const(bigstr) + SvCUR(bigstr));
- stop_pos = littleend - little; /* Actual littlestr len */
- if (stop_pos == 0)
- return (char*)big;
- big -= stop_pos;
- if (*big == first
- && ((stop_pos == 1) ||
- memEQ((char *)(big + 1), (char *)little, stop_pos - 1)))
- return (char*)big;
+ PERL_UNUSED_ARG(bigstr);
+ PERL_UNUSED_ARG(littlestr);
+ PERL_UNUSED_ARG(start_shift);
+ PERL_UNUSED_ARG(end_shift);
+ PERL_UNUSED_ARG(old_posp);
+ PERL_UNUSED_ARG(last);
+
+ /* This function must only ever be called on a scalar with study magic,
+ but those do not happen any more. */
+ Perl_croak(aTHX_ "panic: screaminstr");