Re: BUG REPORT: glibc 2.2 mbrtowc() fails to decode final byte

[Andreas Jaeger <aj at suse dot de>]

>>>>> Ulrich Drepper writes:

 > Markus Kuhn <Markus.Kuhn@cl.cam.ac.uk> writes:
>> The following regression test fails in glibc 2.2 under linux-i386:

 > As Andreas said, this code doesn't fail anymore.  But furthermore it's
 > incorrect:

>> assert(mbrtowc(NULL, NULL, 0, &s) == 0);   /* get s into initial state */

 > This is not how initializing a mbstate_t object can work.  Since the
 > mbrtowc() function can read the mbstate_t object it will read
 > uninitialized memory.  One has to use memset().

Markus told me I can add the following version to glibc.  Uli, is this
ok?

Andreas

2001-01-11  Andreas Jaeger  <aj@suse.de>

	* localedata/mbrtowc-test.c: New file by Markus Kuhn
	<mkuhn@acm.org>.

	* localedata/Makefile (tests): Add mbrtowc-test.
        (mbrtowc-test-ENV): New.

============================================================
Index: localedata/Makefile
--- localedata/Makefile	2000/12/01 00:16:02	1.80
+++ localedata/Makefile	2001/01/11 08:40:43
@@ -1,4 +1,4 @@
-# Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
+# Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
 # This file is part of the GNU C Library.
 
 # The GNU C Library is free software; you can redistribute it and/or
@@ -90,7 +90,7 @@
 		     tst_wcsxfrm tst_wctob tst_wctomb tst_wctrans      \
 		     tst_wctype tst_wcwidth
 
-tests = $(locale_test_suite) tst-digits tst-setlocale
+tests = $(locale_test_suite) tst-digits tst-setlocale mbrtowc-test
 endif
 
 # Files to install.
@@ -254,5 +254,5 @@
 tst_wctype-ENV = $(TEST_MBWC_ENV)
 tst_wcwidth-ENV = $(TEST_MBWC_ENV)
 tst-digits-ENV = $(TEST_MBWC_ENV)
-
+mbrtowc-test-ENV= $(TEST_MBWC_ENV)
 tst-setlocale-ENV = LOCPATH=$(common-objpfx)localedata LC_ALL=ja_JP.EUC-JP
============================================================
Index: localedata/mbrtowc-test.c
--- localedata/mbrtowc-test.c	created
+++ localedata/mbrtowc-test.c	Thu Jan 11 09:18:11 2001	1.1
@@ -0,0 +1,34 @@
+/* Test for mbrtowc, contributed by Markus Kuhn <mkuhn@acm.org>.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <assert.h>
+#include <wchar.h>
+#include <locale.h>
+
+int
+main (void)
+{
+  // UTF-8 single byte feeding test for mbrtowc()
+  wchar_t wc;
+  mbstate_t s;
+  char *locale = "de_DE.UTF-8";
+
+  if (!setlocale (LC_CTYPE, locale))
+    {
+      fprintf (stderr, "locale '%s' not available!\n", locale);
+      exit (1);
+    }
+  wc = 42;			/* arbitrary number */
+  memset (&s, 0, sizeof (s));	/* get s into initial state */
+  assert (mbrtowc (&wc, "\xE2", 1, &s) == (size_t) - 2);	/* 1st byte processed */
+  assert (mbrtowc (&wc, "\x89", 1, &s) == (size_t) - 2);	/* 2nd byte processed */
+  assert (wc == 42);		/* no value has not been stored into &wc yet */
+  assert (mbrtowc (&wc, "\xA0", 1, &s) == 1);	/* 3nd byte processed */
+  assert (wc == 0x2260);	/* E2 89 A0 = U+2260 (not equal) decoded correctly */
+  assert (mbrtowc (&wc, "", 1, &s) == 0);	/* test final byte processing */
+  assert (wc == 0);		/* test final byte decoding */
+
+  return 0;
+}

-- 
 Andreas Jaeger
  SuSE Labs aj@suse.de
   private aj@arthur.inka.de
    http://www.suse.de/~aj