/* Compare strings while treating digits characters numerically.   Copyright (C) 1997, 2000, 2002 Free Software Foundation, Inc.   This file is part of the GNU C Library.   Contributed by Jean-Fran鏾is Bignolles <bignolle@ecoledoc.ibp.fr>, 1997.   The GNU C Library is free software; you can redistribute it and/or   modify it under the terms of the GNU Library General Public License as   published by the Free Software Foundation; either version 2 of the   License, or (at your option) any later version.   The GNU C Library is distributed in the hope that it will be useful,   but WITHOUT ANY WARRANTY; without even the implied warranty of   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU   Library General Public License for more details.   You should have received a copy of the GNU Library General Public   License along with the GNU C Library; see the file COPYING.LIB.  If not,   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,   Boston, MA 02111-1307, USA.  */#if HAVE_CONFIG_H# include <config.h>#endif#include <string.h>#include <ctype.h>/* states: S_N: normal, S_I: comparing integral part, S_F: comparing           fractional 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/* result_type: CMP: return diff; LEN: compare using len_diff/diff */#define CMP    2#define LEN    3/* ISDIGIT differs from isdigit, as follows:   - Its arg may be any int or unsigned int; it need not be an unsigned char.   - It's guaranteed to evaluate its argument exactly once.   - It's typically faster.   POSIX says that only '0' through '9' are digits.  Prefer ISDIGIT to   ISDIGIT_LOCALE unless it's important to use the locale's definition   of `digit' even when the host does not conform to POSIX.  */#define ISDIGIT(c) ((unsigned) (c) - '0' <= 9)#undef __strverscmp#undef strverscmp#ifndef weak_alias# define __strverscmp strverscmp#endif/* 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) -   */  static const unsigned int 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  };  static const int 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  };  if (p1 == p2)    return 0;  c1 = *p1++;  c2 = *p2++;  /* Hint: '0' is a digit too.  */  state = S_N | ((c1 == '0') + (ISDIGIT (c1) != 0));  while ((diff = c1 - c2) == 0 && c1 != '\0')    {      state = next_state[state];      c1 = *p1++;      c2 = *p2++;      state |= (c1 == '0') + (ISDIGIT (c1) != 0);    }  state = result_type[state << 2 | ((c2 == '0') + (ISDIGIT (c2) != 0))];  switch (state)    {    case CMP:      return diff;    case LEN:      while (ISDIGIT (*p1++))	if (!ISDIGIT (*p2++))	  return 1;      return ISDIGIT (*p2) ? -1 : diff;    default:      return state;    }}#ifdef weak_aliasweak_alias (__strverscmp, strverscmp)#endif