libc: update strverscmp

Closes bugzilla #7936

Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

libc/string/strverscmp.c

@@ -1,13 +1,8 @@
-/* GNU's strverscmp() function, taken from glibc 2.3.2 sources
- */
-
 /* Compare strings while treating digits characters numerically.
-   Copyright (C) 1997, 2002 Free Software Foundation, Inc.
+   Copyright (C) 1997-2015 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Jean-François Bignolles <bignolle@ecoledoc.ibp.fr>, 1997.
 
-   Derived work for uClibc by Hai Zaar, Codefidence Ltd <haizaar@codefidence.com>
-
    The GNU C Library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
@@ -22,63 +17,54 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#include <stdint.h>
 #include <string.h>
 #include <ctype.h>
-#include <stdint.h>
-
 
 /* states: S_N: normal, S_I: comparing integral part, S_F: comparing
-   fractional parts, S_Z: idem but with leading Zeroes only */
+           fractionnal parts, S_Z: idem but with leading Zeroes only */
 #define  S_N    0x0
-#define  S_I    0x4
-#define  S_F    0x8
-#define  S_Z    0xC
+#define  S_I    0x3
+#define  S_F    0x6
+#define  S_Z    0x9
 
 /* result_type: CMP: return diff; LEN: compare using len_diff/diff */
 #define  CMP    2
 #define  LEN    3
 
-/* using more efficient isdigit() */
-#undef isdigit
-#define isdigit(a) ((unsigned)((a) - '0') <= 9)
 
 /* Compare S1 and S2 as strings holding indices/version numbers,
    returning less than, equal to or greater than zero if S1 is less than,
    equal to or greater than S2 (for more info, see the texinfo doc).
 */
+
 int strverscmp (const char *s1, const char *s2)
 {
   const unsigned char *p1 = (const unsigned char *) s1;
   const unsigned char *p2 = (const unsigned char *) s2;
-  unsigned char c1, c2;
-  int state;
-  int diff;
 
-  /* Symbol(s)    0       [1-9]   others  (padding)
-     Transition   (10) 0  (01) d  (00) x  (11) -   */
+  /* Symbol(s)    0       [1-9]   others
+     Transition   (10) 0  (01) d  (00) x   */
   static const uint8_t next_state[] =
   {
-      /* state    x    d    0    - */
-      /* S_N */  S_N, S_I, S_Z, S_N,
-      /* S_I */  S_N, S_I, S_I, S_I,
-      /* S_F */  S_N, S_F, S_F, S_F,
-      /* S_Z */  S_N, S_F, S_Z, S_Z
+      /* state    x    d    0  */
+      /* S_N */  S_N, S_I, S_Z,
+      /* S_I */  S_N, S_I, S_I,
+      /* S_F */  S_N, S_F, S_F,
+      /* S_Z */  S_N, S_F, S_Z
   };
 
   static const int8_t result_type[] =
   {
-      /* state   x/x  x/d  x/0  x/-  d/x  d/d  d/0  d/-
-                 0/x  0/d  0/0  0/-  -/x  -/d  -/0  -/- */
-
-      /* S_N */  CMP, CMP, CMP, CMP, CMP, LEN, CMP, CMP,
-                 CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
-      /* S_I */  CMP, -1,  -1,  CMP, +1,  LEN, LEN, CMP,
-                 +1,  LEN, LEN, CMP, CMP, CMP, CMP, CMP,
-      /* S_F */  CMP, CMP, CMP, CMP, CMP, LEN, CMP, CMP,
-                 CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
-      /* S_Z */  CMP, +1,  +1,  CMP, -1,  CMP, CMP, CMP,
-                 -1,  CMP, CMP, CMP
+      /* state   x/x  x/d  x/0  d/x  d/d  d/0  0/x  0/d  0/0  */
+
+      /* S_N */  CMP, CMP, CMP, CMP, LEN, CMP, CMP, CMP, CMP,
+      /* S_I */  CMP, -1,  -1,  +1,  LEN, LEN, +1,  LEN, LEN,
+      /* S_F */  CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
+      /* S_Z */  CMP, +1,  +1,  -1,  CMP, CMP, -1,  CMP, CMP
   };
+  unsigned char c1, c2;
+  int state, diff;
 
   if (p1 == p2)
     return 0;
@@ -86,17 +72,20 @@ int strverscmp (const char *s1, const char *s2)
   c1 = *p1++;
   c2 = *p2++;
   /* Hint: '0' is a digit too.  */
-  state = S_N | ((c1 == '0') + (isdigit (c1) != 0));
+  state = S_N + ((c1 == '0') + (isdigit (c1) != 0));
 
-  while ((diff = c1 - c2) == 0 && c1 != '\0')
+  while ((diff = c1 - c2) == 0)
     {
+      if (c1 == '\0')
+	return diff;
+
       state = next_state[state];
       c1 = *p1++;
       c2 = *p2++;
-      state |= (c1 == '0') + (isdigit (c1) != 0);
+      state += (c1 == '0') + (isdigit (c1) != 0);
     }
 
-  state = result_type[state << 2 | (((c2 == '0') + (isdigit (c2) != 0)))];
+  state = result_type[state * 3 + (((c2 == '0') + (isdigit (c2) != 0)))];
 
   switch (state)
   {