1 /* 2 Copyright (C) 1995 Ian Jackson <iwj10@cus.cam.ac.uk> 3 Copyright (C) 2001 Anthony Towns <aj@azure.humbug.org.au> 4 Copyright (C) 2008-2021 Free Software Foundation, Inc. 5 6 This file is free software: you can redistribute it and/or modify 7 it under the terms of the GNU Lesser General Public License as 8 published by the Free Software Foundation; either version 3 of the 9 License, or (at your option) any later version. 10 11 This file is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU Lesser General Public License for more details. 15 16 You should have received a copy of the GNU Lesser General Public License 17 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 18 19 #ifndef FILEVERCMP_H 20 #define FILEVERCMP_H 21 22 /* Compare version strings: 23 24 This function compares strings S1 and S2: 25 1) By PREFIX in the same way as strcmp. 26 2) Then by VERSION (most similarly to version compare of Debian's dpkg). 27 Leading zeros in version numbers are ignored. 28 3) If both (PREFIX and VERSION) are equal, strcmp function is used for 29 comparison. So this function can return 0 if (and only if) strings S1 30 and S2 are identical. 31 32 It returns number >0 for S1 > S2, 0 for S1 == S2 and number <0 for S1 < S2. 33 34 This function compares strings, in a way that if VER1 and VER2 are version 35 numbers and PREFIX and SUFFIX (SUFFIX defined as (\.[A-Za-z~][A-Za-z0-9~]*)*) 36 are strings then VER1 < VER2 implies filevercmp (PREFIX VER1 SUFFIX, 37 PREFIX VER2 SUFFIX) < 0. 38 39 This function is intended to be a replacement for strverscmp. */ 40 int filevercmp (const char *s1, const char *s2) _GL_ATTRIBUTE_PURE; 41 42 #endif /* FILEVERCMP_H */