X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/685289b5657b776e8a3871de68a57785e6ccd797..0c415a7950ced3bdd13d9361e7154695c677851b:/utf8.c

diff --git a/utf8.c b/utf8.c
index 6600023..184e429 100644
--- a/utf8.c
+++ b/utf8.c
@@ -507,7 +507,13 @@ determinable reasonable value.
 The UTF8_CHECK_ONLY flag overrides the behavior when a non-allowed (by other
 flags) malformation is found.  If this flag is set, the routine assumes that
 the caller will raise a warning, and this function will silently just set
-C<retlen> to C<-1> and return zero.
+C<retlen> to C<-1> (cast to C<STRLEN>) and return zero.
+
+Note that this API requires disambiguation between successful decoding a NUL
+character, and an error return (unless the UTF8_CHECK_ONLY flag is set), as
+in both cases, 0 is returned.  To disambiguate, upon a zero return, see if the
+first byte of C<s> is 0 as well.  If so, the input was a NUL; if not, the input
+had an error.
 
 Certain code points are considered problematic.  These are Unicode surrogates,
 Unicode non-characters, and code points above the Unicode maximum of 0x10FFFF.
@@ -1096,10 +1102,7 @@ Perl_utf8_length(pTHX_ const U8 *s, const U8 *e)
     if (e < s)
 	goto warn_and_return;
     while (s < e) {
-	if (!UTF8_IS_INVARIANT(*s))
-	    s += UTF8SKIP(s);
-	else
-	    s++;
+        s += UTF8SKIP(s);
 	len++;
     }
 
@@ -2863,19 +2866,21 @@ Perl__core_swash_init(pTHX_ const char* pkg, const char* name, SV *listsv, I32 m
 	if (!method) {	/* demand load utf8 */
 	    ENTER;
 	    errsv_save = newSVsv(ERRSV);
+	    SAVEFREESV(errsv_save);
 	    /* It is assumed that callers of this routine are not passing in
 	     * any user derived data.  */
 	    /* Need to do this after save_re_context() as it will set
 	     * PL_tainted to 1 while saving $1 etc (see the code after getrx:
 	     * in Perl_magic_get).  Even line to create errsv_save can turn on
 	     * PL_tainted.  */
-	    SAVEBOOL(PL_tainted);
-	    PL_tainted = 0;
+#ifndef NO_TAINT_SUPPORT
+	    SAVEBOOL(TAINT_get);
+	    TAINT_NOT;
+#endif
 	    Perl_load_module(aTHX_ PERL_LOADMOD_NOIMPORT, newSVpvn(pkg,pkg_len),
 			     NULL);
 	    if (!SvTRUE(ERRSV))
 		sv_setsv(ERRSV, errsv_save);
-	    SvREFCNT_dec(errsv_save);
 	    LEAVE;
 	}
 	SPAGAIN;
@@ -2888,6 +2893,7 @@ Perl__core_swash_init(pTHX_ const char* pkg, const char* name, SV *listsv, I32 m
 	mPUSHi(none);
 	PUTBACK;
 	errsv_save = newSVsv(ERRSV);
+	SAVEFREESV(errsv_save);
 	/* If we already have a pointer to the method, no need to use
 	 * call_method() to repeat the lookup.  */
 	if (method ? call_sv(MUTABLE_SV(method), G_SCALAR)
@@ -2898,7 +2904,6 @@ Perl__core_swash_init(pTHX_ const char* pkg, const char* name, SV *listsv, I32 m
 	}
 	if (!SvTRUE(ERRSV))
 	    sv_setsv(ERRSV, errsv_save);
-	SvREFCNT_dec(errsv_save);
 	LEAVE;
 	POPSTACK;
 	if (IN_PERL_COMPILETIME) {
@@ -3609,7 +3614,7 @@ HV*
 Perl__swash_inversion_hash(pTHX_ SV* const swash)
 {
 
-   /* Subject to change or removal.  For use only in one place in regcomp.c.
+   /* Subject to change or removal.  For use only in regcomp.c and regexec.c
     * Can't be used on a property that is subject to user override, as it
     * relies on the value of SPECIALS in the swash which would be set by
     * utf8_heavy.pl to the hash in the non-overriden file, and hence is not set
@@ -4297,9 +4302,11 @@ scanning won't continue past that goal.  Correspondingly for C<l2> with respect
 C<s2>.
 
 If C<pe1> is non-NULL and the pointer it points to is not NULL, that pointer is
-considered an end pointer beyond which scanning of C<s1> will not continue under
-any circumstances.  This means that if both C<l1> and C<pe1> are specified, and
-C<pe1>
+considered an end pointer to the position 1 byte past the maximum point
+in C<s1> beyond which scanning will not continue under any circumstances.
+(This routine assumes that UTF-8 encoded input strings are not malformed;
+malformed input can cause it to read past C<pe1>).
+This means that if both C<l1> and C<pe1> are specified, and C<pe1>
 is less than C<s1>+C<l1>, the match will never be successful because it can
 never
 get as far as its goal (and in fact is asserted against).  Correspondingly for