From: SADAHIRO Tomoyuki <BQW10602@nifty.com>
Date: Sun, 21 May 2006 19:33:21 +0000 (+0900)
Subject: Re: [perl #39126] possible memory related bug when using sprintf with an utf-8 encode... 
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=cc61b222958c07650542902d07ee4c04d4d76213;p=p5sagit%2Fp5-mst-13.2.git

Re: [perl #39126] possible memory related bug when using sprintf with an utf-8 encoded format-string and iso-8859-1 encoded string variables.
Message-Id: <20060521193259.81E5.BQW10602@nifty.com>

with test tweaks further suggested by the same

p4raw-id: //depot/perl@28328
---

diff --git a/sv.c b/sv.c
index d6e307d..3653b86 100644
--- a/sv.c
+++ b/sv.c
@@ -9338,27 +9338,29 @@ Perl_sv_vcatpvfn(pTHX_ SV *sv, const char *pat, STRLEN patlen, va_list *args, SV
 	    continue;	/* not "break" */
 	}
 
-	/* calculate width before utf8_upgrade changes it */
+	if (is_utf8 != has_utf8) {
+	    if (is_utf8) {
+		if (SvCUR(sv))
+		    sv_utf8_upgrade(sv);
+	    }
+	    else {
+		const STRLEN old_elen = elen;
+		SV * const nsv = sv_2mortal(newSVpvn(eptr, elen));
+		sv_utf8_upgrade(nsv);
+		eptr = SvPVX_const(nsv);
+		elen = SvCUR(nsv);
+
+		if (width) { /* fudge width (can't fudge elen) */
+		    width += elen - old_elen;
+		}
+		is_utf8 = TRUE;
+	    }
+	}
+
 	have = esignlen + zeros + elen;
 	if (have < zeros)
 	    Perl_croak_nocontext(PL_memory_wrap);
 
-	if (is_utf8 != has_utf8) {
-	     if (is_utf8) {
-		  if (SvCUR(sv))
-		       sv_utf8_upgrade(sv);
-	     }
-	     else {
-		  SV * const nsv = sv_2mortal(newSVpvn(eptr, elen));
-		  sv_utf8_upgrade(nsv);
-		  eptr = SvPVX_const(nsv);
-		  elen = SvCUR(nsv);
-	     }
-	     SvGROW(sv, SvCUR(sv) + elen + 1);
-	     p = SvEND(sv);
-	     *p = '\0';
-	}
-
 	need = (have > width ? have : width);
 	gap = need - have;
 
diff --git a/t/op/sprintf2.t b/t/op/sprintf2.t
index 7544705..81450ce 100644
--- a/t/op/sprintf2.t
+++ b/t/op/sprintf2.t
@@ -6,7 +6,7 @@ BEGIN {
     require './test.pl';
 }   
 
-plan tests => 275;
+plan tests => 280;
 
 is(
     sprintf("%.40g ",0.01),
@@ -18,13 +18,14 @@ is(
     sprintf("%.40f", 0.01)." ",
     q(the sprintf "%.<number>f" optimization)
 );
-{
-	chop(my $utf8_format = "%-3s\x{100}");
-	is(
-		sprintf($utf8_format, "\xe4"),
-		"\xe4  ",
-		q(width calculation under utf8 upgrade)
-	);
+
+# cases of $i > 1 are against [perl #39126]
+for my $i (1, 5, 10, 20, 50, 100) {
+    chop(my $utf8_format = "%-*s\x{100}");
+    my $string = "\xB4"x$i;        # latin1 ACUTE or ebcdic COPYRIGHT
+    my $expect = $string."  "x$i;  # followed by 2*$i spaces
+    is(sprintf($utf8_format, 3*$i, $string), $expect,
+       "width calculation under utf8 upgrade, length=$i");
 }
 
 # Used to mangle PL_sv_undef