Short description: fnmatch() fails with MBCS.
Author(s): Fedora glibc team <glibc@lists.fedoraproject.org>
Origin: PATCH
Bug-RHEL: #819430, #826149, #826151
Bug-Upstream: #14185
Upstream status: not-submitted

fnmatch() fails when '*' wildcard is applied on the file name
containing multi-byte character(s)

This needs to be reviewed thoroughly and go upstream with a
new test case.


diff --git a/posix/fnmatch.c b/posix/fnmatch.c
index 5896812c966ac7c6..63df3dae0911030f 100644
--- a/posix/fnmatch.c
+++ b/posix/fnmatch.c
@@ -237,6 +237,7 @@ fnmatch (const char *pattern, const char *string, int flags)
 {
   if (__glibc_unlikely (MB_CUR_MAX != 1))
     {
+      const char *orig_pattern = pattern;
       mbstate_t ps;
       size_t n;
       const char *p;
@@ -256,10 +257,8 @@ fnmatch (const char *pattern, const char *string, int flags)
                                                  alloca_used);
           n = mbsrtowcs (wpattern, &p, n + 1, &ps);
           if (__glibc_unlikely (n == (size_t) -1))
-            /* Something wrong.
-               XXX Do we have to set 'errno' to something which mbsrtows hasn't
-               already done?  */
-            return -1;
+	    /* Something wrong: Fall back to single byte matching.  */
+	    goto try_singlebyte;
           if (p)
             {
               memset (&ps, '\0', sizeof (ps));
@@ -271,10 +270,8 @@ fnmatch (const char *pattern, const char *string, int flags)
         prepare_wpattern:
           n = mbsrtowcs (NULL, &pattern, 0, &ps);
           if (__glibc_unlikely (n == (size_t) -1))
-            /* Something wrong.
-               XXX Do we have to set 'errno' to something which mbsrtows hasn't
-               already done?  */
-            return -1;
+	    /* Something wrong: Fall back to single byte matching.  */
+	    goto try_singlebyte;
           if (__glibc_unlikely (n >= (size_t) -1 / sizeof (wchar_t)))
             {
               __set_errno (ENOMEM);
@@ -297,14 +294,8 @@ fnmatch (const char *pattern, const char *string, int flags)
                                                 alloca_used);
           n = mbsrtowcs (wstring, &p, n + 1, &ps);
           if (__glibc_unlikely (n == (size_t) -1))
-            {
-              /* Something wrong.
-                 XXX Do we have to set 'errno' to something which
-                 mbsrtows hasn't already done?  */
-            free_return:
-              free (wpattern_malloc);
-              return -1;
-            }
+	    /* Something wrong: Fall back to single byte matching.  */
+	    goto free_and_try_singlebyte;
           if (p)
             {
               memset (&ps, '\0', sizeof (ps));
@@ -316,10 +307,8 @@ fnmatch (const char *pattern, const char *string, int flags)
         prepare_wstring:
           n = mbsrtowcs (NULL, &string, 0, &ps);
           if (__glibc_unlikely (n == (size_t) -1))
-            /* Something wrong.
-               XXX Do we have to set 'errno' to something which mbsrtows hasn't
-               already done?  */
-            goto free_return;
+	    /* Something wrong: Fall back to singlebyte matching. */
+	    goto free_and_try_singlebyte;
           if (__glibc_unlikely (n >= (size_t) -1 / sizeof (wchar_t)))
             {
               free (wpattern_malloc);
@@ -346,6 +335,10 @@ fnmatch (const char *pattern, const char *string, int flags)
       free (wpattern_malloc);
 
       return res;
+      free_and_try_singlebyte:
+	free(wpattern_malloc);
+      try_singlebyte:
+	pattern = orig_pattern;
     }
 
   return internal_fnmatch (pattern, string, string + strlen (string),