[PATCH] regcomp.c: make non-_LIBC implementation of build_range_exp consistent

[Jim Meyering]

Here's part 2.
I'll push it tomorrow.

>From c13c8d014bc43ae8da0b75cc86869a73aa84d6b9 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Fri, 19 Mar 2010 21:26:36 +0100
Subject: [PATCH] regcomp.c: make non-_LIBC implementation of build_range_exp 
consistent

The _LIBC implementation of build_range_exp correctly honors the
RE_NO_EMPTY_RANGES flag when checking for reversed range endpoints.
However, the non-_LIBC implementation would ignore that syntax-bit
flag and return REG_ERANGE unconditionally.
This change makes it honor that flag.
* lib/regcomp.c (build_range_exp) [!_LIBC]: Add a parameter: "syntax".
Make two pointer parameters "const".
Use "syntax" bits in order to honor RE_NO_EMPTY_RANGES.
(parse_bracket_exp): Update caller.
---
 ChangeLog     |   11 +++++++++++
 lib/regcomp.c |   22 +++++++++++++++-------
 2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 7fe9472..54e0a66 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,16 @@
 2010-03-19  Jim Meyering  <address@hidden>

+       regcomp.c: make non-_LIBC implementation of build_range_exp consistent
+       The _LIBC implementation of build_range_exp correctly honors the
+       RE_NO_EMPTY_RANGES flag when checking for reversed range endpoints.
+       However, the non-_LIBC implementation would ignore that syntax-bit
+       flag and return REG_ERANGE unconditionally.
+       This change makes it honor that flag.
+       * lib/regcomp.c (build_range_exp) [!_LIBC]: Add a parameter: "syntax".
+       Make two pointer parameters "const".
+       Use "syntax" bits in order to honor RE_NO_EMPTY_RANGES.
+       (parse_bracket_exp): Update caller.
+
        regex.m4: correct the reversed range endpoint ([b-a]) test
        * m4/regex.m4: When requiring that [b-a] evoke failure,
        use RE_NO_EMPTY_RANGES.  This makes this entire configure-time
diff --git a/lib/regcomp.c b/lib/regcomp.c
index d5968bd..7eff569 100644
--- a/lib/regcomp.c
+++ b/lib/regcomp.c
@@ -2622,11 +2622,17 @@ parse_dup_op (bin_tree_t *elem, re_string_t *regexp, 
re_dfa_t *dfa,
 static reg_errcode_t
 internal_function
 # ifdef RE_ENABLE_I18N
-build_range_exp (bitset_t sbcset, re_charset_t *mbcset, Idx *range_alloc,
-                bracket_elem_t *start_elem, bracket_elem_t *end_elem)
+build_range_exp (const reg_syntax_t syntax,
+                 bitset_t sbcset,
+                 re_charset_t *mbcset,
+                 Idx *range_alloc,
+                 const bracket_elem_t *start_elem,
+                 const bracket_elem_t *end_elem)
 # else /* not RE_ENABLE_I18N */
-build_range_exp (bitset_t sbcset, bracket_elem_t *start_elem,
-                bracket_elem_t *end_elem)
+build_range_exp (const reg_syntax_t syntax,
+                 bitset_t sbcset,
+                 const bracket_elem_t *start_elem,
+                 const bracket_elem_t *end_elem)
 # endif /* not RE_ENABLE_I18N */
 {
   unsigned int start_ch, end_ch;
@@ -2665,7 +2671,9 @@ build_range_exp (bitset_t sbcset, bracket_elem_t 
*start_elem,
       return REG_ECOLLATE;
     cmp_buf[0] = start_wc;
     cmp_buf[4] = end_wc;
-    if (wcscoll (cmp_buf, cmp_buf + 4) > 0)
+
+    if (BE ((syntax & RE_NO_EMPTY_RANGES)
+            && wcscoll (cmp_buf, cmp_buf + 4) > 0, 0))
       return REG_ERANGE;

     /* Got valid collation sequence values, add them as a new entry.
@@ -3168,11 +3176,11 @@ parse_bracket_exp (re_string_t *regexp, re_dfa_t *dfa, 
re_token_t *token,
                                  &start_elem, &end_elem);
 #else
 # ifdef RE_ENABLE_I18N
-         *err = build_range_exp (sbcset,
+         *err = build_range_exp (syntax, sbcset,
                                  dfa->mb_cur_max > 1 ? mbcset : NULL,
                                  &range_alloc, &start_elem, &end_elem);
 # else
-         *err = build_range_exp (sbcset, &start_elem, &end_elem);
+         *err = build_range_exp (syntax, sbcset, &start_elem, &end_elem);
 # endif
 #endif /* RE_ENABLE_I18N */
          if (BE (*err != REG_NOERROR, 0))
--
1.7.0.2.455.g91132