update.

* libio/wfileops.c (_IO_wfile_underflow): Remove incorrect test
	for possible conversion using __codecvt_do_in.
	* libio/Makefile (tests): Add tst-fgetws.
	* libio/tst-fgetws.c: New file.

	* libio/iofgetws.c: Use _IO_ferror_unlocked macros instead of
	coding the test here.

libio/tst-fgetws.c

@@ -0,0 +1,185 @@
+/* Taken from the Li18nux base test suite.  */
+
+#define _XOPEN_SOURCE 500
+#include <errno.h>
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <wchar.h>
+
+#define WIDE_STR_LEN 32
+
+int
+main (int argc, char *argv[])
+{
+  int i;
+  FILE   *fp;
+  wchar_t *ret, wcs[WIDE_STR_LEN];
+  int result = 0;
+  const char il_str1[] = {0xe3, 0x81, '\0'};
+  const char il_str2[] = {'0', '\n', 'A', 'B', 0xe3, 0x81, 'E', '\0'};
+  char name1[] = "/tmp/tst-fgetws.out.XXXXXX";
+  char name2[] = "/tmp/tst-fgetws.out.XXXXXX";
+  int fd;
+
+  puts ("This program runs on de_DE.UTF-8 locale.");
+  if (setlocale (LC_ALL, "de_DE.UTF-8") == NULL)
+    {
+      fprintf (stderr, "Err: Cannot run on the de_DE.UTF-8 locale");
+      exit (EXIT_FAILURE);
+    }
+
+  /* Make a file `il_str1'. */
+  fd = mkstemp (name1);
+  if (fd == -1)
+    {
+      printf ("cannot open temp file: %m\n");
+      exit (EXIT_FAILURE);
+    }
+  if ((fp = fdopen (fd, "w")) == NULL)
+    {
+      printf ("Can't open %s.\n", argv[1]);
+      exit (EXIT_FAILURE);
+    }
+  fwrite (il_str1, sizeof (char), sizeof (il_str1), fp);
+  fclose (fp);
+
+  /* Make a file `il_str2'. */
+  fd = mkstemp (name2);
+  if (fd == -1)
+    {
+      printf ("cannot open temp file: %m\n");
+      exit (EXIT_FAILURE);
+    }
+  if ((fp = fdopen (fd, "w")) == NULL)
+    {
+      fprintf (stderr, "Can't open %s.\n", argv[1]);
+      exit (EXIT_FAILURE);
+    }
+  fwrite (il_str2, sizeof (char), sizeof (il_str2), fp);
+  fclose (fp);
+
+
+  /* Test for il_str1. */
+  if ((fp = fopen (name1, "r")) == NULL)
+    {
+      fprintf (stderr, "Can't open %s.\n", argv[1]);
+      exit (EXIT_FAILURE);
+    }
+
+  puts ("--");
+  puts ("Read a byte sequence which is invalid as a wide character string.");
+  puts (" bytes: 0xe3, 0x81, '\\0'");
+
+  errno = 0;
+  ret = fgetws (wcs, WIDE_STR_LEN, fp);
+
+  if (ret == NULL)
+    {
+      puts ("Return Value: NULL");
+
+      if (errno == EILSEQ)
+	puts ("errno = EILSEQ");
+      else
+	{
+	  printf ("errno = %d\n", errno);
+	  result = 1;
+	}
+    }
+  else
+    {
+      printf ("Return Value: %p\n", ret);
+      for (i = 0; i < wcslen (wcs) + 1; i++)
+	printf (" wcs[%d] = %04x", i, (unsigned int)wcs[i]);
+      printf ("\n");
+      result = 1;
+    }
+
+  /* Test for il_str2. */
+  if ((fp = fopen (name2, "r")) == NULL)
+    {
+      fprintf (stderr, "Can't open %s.\n", argv[1]);
+      exit (EXIT_FAILURE);
+    }
+
+  puts ("--");
+  puts ("Read a byte sequence which is invalid as a wide character string.");
+  puts (" bytes: '0', '\\n', 'A', 'B', 0xe3, 0x81, 'c', '\\0'");
+
+  errno = 0;
+  ret = fgetws (wcs, WIDE_STR_LEN, fp);
+
+  if (ret == NULL)
+    {
+      puts ("Return Value: NULL");
+
+      if (errno == EILSEQ)
+	puts ("errno = EILSEQ");
+      else
+	printf ("errno = %d\n", errno);
+
+      result = 1;
+    }
+  else
+    {
+      int i;
+
+      printf ("Return Value: %p\n", ret);
+      for (i = 0; i < wcslen (wcs) + 1; i++)
+	printf (" wcs[%d] = 0x%04x", i, (unsigned int)wcs[i]);
+      printf ("\n");
+
+      for (i = 0; il_str2[i] != '\n'; ++i)
+	if ((wchar_t) il_str2[i] != wcs[i])
+	  {
+	    puts ("read string not correct");
+	    result = 1;
+	    break;
+	  }
+      if (il_str2[i] == '\n')
+	{
+	  if (wcs[i] != L'\n')
+	    {
+	      puts ("newline missing");
+	      result = 1;
+	    }
+	  else if (wcs[i + 1] != L'\0')
+	    {
+	      puts ("read string not NUL-terminated");
+	      result = 1;
+	    }
+	}
+    }
+
+  puts ("\nsecond line");
+  errno = 0;
+  ret = fgetws (wcs, WIDE_STR_LEN, fp);
+
+  if (ret == NULL)
+    {
+      puts ("Return Value: NULL");
+
+      if (errno == EILSEQ)
+	puts ("errno = EILSEQ");
+      else
+	{
+	  printf ("errno = %d\n", errno);
+	  result = 1;
+	}
+    }
+  else
+    {
+      printf ("Return Value: %p\n", ret);
+      for (i = 0; i < wcslen (wcs) + 1; i++)
+	printf (" wcs[%d] = 0x%04x", i, (unsigned int)wcs[i]);
+      printf ("\n");
+    }
+
+  fclose (fp);
+
+  unlink (name1);
+  unlink (name2);
+
+  return result;
+}