1 /* GNU's strverscmp() function, taken from glibc 2.3.2 sources
2 */
3
4 /* Compare strings while treating digits characters numerically.
5 Copyright (C) 1997, 2002 Free Software Foundation, Inc.
6 This file is part of the GNU C Library.
7 Contributed by Jean-Fran�ois Bignolles <bignolle@ecoledoc.ibp.fr>, 1997.
8
9 Derived work for uClibc by Hai Zaar, Codefidence Ltd <haizaar@codefidence.com>
10
11 The GNU C Library is free software; you can redistribute it and/or
12 modify it under the terms of the GNU Lesser General Public
13 License as published by the Free Software Foundation; either
14 version 2.1 of the License, or (at your option) any later version.
15
16 The GNU C Library is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 Lesser General Public License for more details.
20
21 You should have received a copy of the GNU Lesser General Public
22 License along with the GNU C Library; if not, see
23 <http://www.gnu.org/licenses/>. */
24
25 #include <string.h>
26 #include <ctype.h>
27 #include <stdint.h>
28
29
30 /* states: S_N: normal, S_I: comparing integral part, S_F: comparing
31 fractional parts, S_Z: idem but with leading Zeroes only */
32 #define S_N 0x0
33 #define S_I 0x4
34 #define S_F 0x8
35 #define S_Z 0xC
36
37 /* result_type: CMP: return diff; LEN: compare using len_diff/diff */
38 #define CMP 2
39 #define LEN 3
40
41 /* using more efficient isdigit() */
42 #undef isdigit
43 #define isdigit(a) ((unsigned)((a) - '0') <= 9)
44
45 /* Compare S1 and S2 as strings holding indices/version numbers,
46 returning less than, equal to or greater than zero if S1 is less than,
47 equal to or greater than S2 (for more info, see the texinfo doc).
48 */
strverscmp(const char * s1,const char * s2)49 int strverscmp (const char *s1, const char *s2)
50 {
51 const unsigned char *p1 = (const unsigned char *) s1;
52 const unsigned char *p2 = (const unsigned char *) s2;
53 unsigned char c1, c2;
54 int state;
55 int diff;
56
57 /* Symbol(s) 0 [1-9] others (padding)
58 Transition (10) 0 (01) d (00) x (11) - */
59 static const uint8_t next_state[] =
60 {
61 /* state x d 0 - */
62 /* S_N */ S_N, S_I, S_Z, S_N,
63 /* S_I */ S_N, S_I, S_I, S_I,
64 /* S_F */ S_N, S_F, S_F, S_F,
65 /* S_Z */ S_N, S_F, S_Z, S_Z
66 };
67
68 static const int8_t result_type[] =
69 {
70 /* state x/x x/d x/0 x/- d/x d/d d/0 d/-
71 0/x 0/d 0/0 0/- -/x -/d -/0 -/- */
72
73 /* S_N */ CMP, CMP, CMP, CMP, CMP, LEN, CMP, CMP,
74 CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
75 /* S_I */ CMP, -1, -1, CMP, +1, LEN, LEN, CMP,
76 +1, LEN, LEN, CMP, CMP, CMP, CMP, CMP,
77 /* S_F */ CMP, CMP, CMP, CMP, CMP, LEN, CMP, CMP,
78 CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
79 /* S_Z */ CMP, +1, +1, CMP, -1, CMP, CMP, CMP,
80 -1, CMP, CMP, CMP
81 };
82
83 if (p1 == p2)
84 return 0;
85
86 c1 = *p1++;
87 c2 = *p2++;
88 /* Hint: '0' is a digit too. */
89 state = S_N | ((c1 == '0') + (isdigit (c1) != 0));
90
91 while ((diff = c1 - c2) == 0 && c1 != '\0')
92 {
93 state = next_state[state];
94 c1 = *p1++;
95 c2 = *p2++;
96 state |= (c1 == '0') + (isdigit (c1) != 0);
97 }
98
99 state = result_type[state << 2 | (((c2 == '0') + (isdigit (c2) != 0)))];
100
101 switch (state)
102 {
103 case CMP:
104 return diff;
105
106 case LEN:
107 while (isdigit (*p1++))
108 if (!isdigit (*p2++))
109 return 1;
110
111 return isdigit (*p2) ? -1 : diff;
112
113 default:
114 return state;
115 }
116 }
117 libc_hidden_def(strverscmp)
118