Avoid tr case-conversion failure in some locales.

* src/tr.c (skip_construct): New function.
(main): When processing a pair of case-converting classes, don't
iterate through the elements of each [:upper:] or [:lower:] class.
Reported by Gerald Pfeifer in
<http://thread.gmane.org/gmane.comp.gnu.coreutils.bugs/12218>.
* tests/tr/Test.pm [tolower-F]: New test for the above fix.
[upcase-xtra, dncase-xtra]: New tests, for a related code path.
* NEWS: Mention the tr bug fix.

ChangeLog

@@ -1,3 +1,15 @@
+2008-01-05  Jim Meyering  <meyering@redhat.com>
+
+	Avoid tr case-conversion failure in some locales.
+	* src/tr.c (skip_construct): New function.
+	(main): When processing a pair of case-converting classes, don't
+	iterate through the elements of each [:upper:] or [:lower:] class.
+	Reported by Gerald Pfeifer in
+	<http://thread.gmane.org/gmane.comp.gnu.coreutils.bugs/12218>.
+	* tests/tr/Test.pm [tolower-F]: New test for the above fix.
+	[upcase-xtra, dncase-xtra]: New tests, for a related code path.
+	* NEWS: Mention the tr bug fix.
+
 2008-01-02  Jim Meyering  <jim@meyering.net>
 
 	* .gitignore: Ignore lzma-compressed files, too.

NEWS

@@ -2,6 +2,12 @@ GNU coreutils NEWS                                    -*- outline -*-
 
 * Noteworthy changes in release 6.? (????-??-??) [?]
 
+** Bug fixes
+
+  tr's case conversion would fail in a locale with differing numbers
+  of lower case and upper case characters.  E.g., this would fail:
+  env LC_CTYPE=en_US.iso88591 tr '[:upper:]' '[:lower:]'
+  [bug introduced in coreutils-6.9.90]
 
 
 * Noteworthy changes in release 6.9.91 (2007-12-15) [beta]

THANKS

@@ -179,6 +179,7 @@ Geoff Collyer                       geoff at collyer.net
 Geoff Kuenning                      geoff@cs.hmc.edu
 Geoff Odhner                        geoff@franklin.com
 Geoff Whale                         geoffw@cse.unsw.EDU.AU
+Gerald Pfeifer                      gerald@pfeifer.com
 Gerhard Poul                        gpoul@gnu.org
 Germano Leichsenring                germano@jedi.cs.kobe-u.ac.jp
 Göran Uddeborg                      goeran@uddeborg.pp.se

src/tr.c

@@ -1,5 +1,5 @@
 /* tr -- a filter to translate characters
-   Copyright (C) 91, 1995-2007 Free Software Foundation, Inc.
+   Copyright (C) 91, 1995-2008 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -1019,6 +1019,15 @@ build_spec_list (const struct E_string *es, struct Spec_list *result)
   return true;
 }
 
+/* Advance past the current construct.
+   S->tail must be non-NULL.  */
+static void
+skip_construct (struct Spec_list *s)
+{
+  s->tail = s->tail->next;
+  s->state = NEW_ELEMENT;
+}
+
 /* Given a Spec_list S (with its saved state implicit in the values
    of its members `tail' and `state'), return the next single character
    in the expansion of S's constructs.  If the last character of S was
@@ -1809,6 +1818,7 @@ main (int argc, char **argv)
 	{
 	  int c1, c2;
 	  int i;
+	  bool case_convert = false;
 	  enum Upper_Lower_class class_s1;
 	  enum Upper_Lower_class class_s2;
 
@@ -1818,6 +1828,16 @@ main (int argc, char **argv)
 	  s2->state = BEGIN_STATE;
 	  for (;;)
 	    {
+	      /* When the previous pair identified case-converting classes,
+		 advance S1 and S2 so that each points to the following
+		 construct.  */
+	      if (case_convert)
+		{
+		  skip_construct (s1);
+		  skip_construct (s2);
+		  case_convert = false;
+		}
+
 	      c1 = get_next (s1, &class_s1);
 	      c2 = get_next (s2, &class_s2);
 
@@ -1831,12 +1851,14 @@ main (int argc, char **argv)
 
 	      if (class_s1 == UL_LOWER && class_s2 == UL_UPPER)
 		{
+		  case_convert = true;
 		  for (i = 0; i < N_CHARS; i++)
 		    if (islower (i))
 		      xlate[i] = toupper (i);
 		}
 	      else if (class_s1 == UL_UPPER && class_s2 == UL_LOWER)
 		{
+		  case_convert = true;
 		  for (i = 0; i < N_CHARS; i++)
 		    if (isupper (i))
 		      xlate[i] = tolower (i);

tests/tr/Test.pm

@@ -139,8 +139,20 @@ my @tv = (
 # Up to coreutils-6.9, tr rejected an unmatched [:lower:] or [:upper:] in SET1.
 ['s1-lower', q|'[:lower:]' '[.*]'|, '#$%123abcABC', '#$%123...ABC', 0],
 ['s1-upper', q|'[:upper:]' '[.*]'|, '#$%123abcABC', '#$%123abc...', 0],
+
+# Up to coreutils-6.9.91, this would fail with the diagnostic:
+# tr: misaligned [:upper:] and/or [:lower:] construct
+# with LC_CTYPE=en_US.iso88591.
+['tolower-F',q|'[:upper:]' '[:lower:]'|, 'A', 'a', 0],
+
+# When doing a case-converting translation with something after the
+# [:upper:] and [:lower:] elements, ensure that tr honors the following byte.
+['upcase-xtra',q|'[:lower:].' '[:upper:]x'|,	'abc.', 'ABCx', 0],
+['dncase-xtra',q|'[:upper:].' '[:lower:]x'|,	'ABC.', 'abcx', 0],
 );
 
+$Test::env{'tolower-F'} = ['LC_CTYPE=en_US.iso88591'];
+
 sub test_vector
 {
   my $t;