5 * Compare version numbers using the Debian algorithm
7 * (c) 2007 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of the mLib utilities library.
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 #ifndef MLIB_VERSIONCMP_H
31 #define MLIB_VERSIONCMP_H
37 /*----- Functions provided ------------------------------------------------*/
39 /* --- @versioncmp@ --- *
41 * Arguments: @const char *va, *vb@ = two version strings
43 * Returns: Less than, equal to, or greater than zero, according to
44 * whether @va@ is less than, equal to, or greater than @vb@.
46 * Use: Compares version number strings.
48 * The algorithm is an extension of the Debian version
49 * comparison algorithm. A version number consists of three
52 * [EPOCH :] MAIN [- SUB]
54 * The MAIN part may contain colons or hyphens if there is an
55 * EPOCH or SUB, respectively. Version strings are compared
56 * componentwise: first epochs, then main parts, and finally
59 * The component comparison is done as follows. First, the
60 * initial subsequence of nondigit characters is extracted from
61 * each string, and these are compared lexicographically, using
62 * ASCII ordering, except that letters precede non-letters. If
63 * both are the same, an initial sequence of digits is extracted
64 * from the remaining parts of the version strings, and these
65 * are compared numerically (an empty sequence being considered
66 * to have the value zero). This process is repeated until we
67 * have a winner or until both strings are exhausted.
70 extern int versioncmp(const char */*va*/, const char */*vb*/);
72 /*----- That's all, folks -------------------------------------------------*/