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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 16:11:47 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 16:11:47 +0000 |
commit | 758f820bcc0f68aeebac1717e537ca13a320b909 (patch) | |
tree | 48111ece75cf4f98316848b37a7e26356e00669e /lib/filevercmp.h | |
parent | Initial commit. (diff) | |
download | coreutils-upstream.tar.xz coreutils-upstream.zip |
Adding upstream version 9.1.upstream/9.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/filevercmp.h')
-rw-r--r-- | lib/filevercmp.h | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/lib/filevercmp.h b/lib/filevercmp.h new file mode 100644 index 0000000..5a33677 --- /dev/null +++ b/lib/filevercmp.h @@ -0,0 +1,76 @@ +/* Compare file names containing version numbers. + + Copyright (C) 1995 Ian Jackson <iwj10@cus.cam.ac.uk> + Copyright (C) 2001 Anthony Towns <aj@azure.humbug.org.au> + Copyright (C) 2008-2022 Free Software Foundation, Inc. + + This file 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 version 3 of the + License, or (at your option) any later version. + + This file 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 Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +#ifndef FILEVERCMP_H +#define FILEVERCMP_H + +#include <stddef.h> + +/* Compare strings A and B as file names containing version numbers, + and return an integer that is negative, zero, or positive depending + on whether A compares less than, equal to, or greater than B. + + Use the following version sort algorithm: + + 1. Compare the strings' maximal-length non-digit prefixes lexically. + If there is a difference return that difference. + Otherwise discard the prefixes and continue with the next step. + + 2. Compare the strings' maximal-length digit prefixes, using + numeric comparison of the numbers represented by each prefix. + (Treat an empty prefix as zero; this can happen only at string end.) + If there is a difference, return that difference. + Otherwise discard the prefixes and continue with the next step. + + 3. If both strings are empty, return 0. Otherwise continue with step 1. + + In version sort, lexical comparison is left to right, byte by byte, + using the byte's numeric value (0-255), except that: + + 1. ASCII letters sort before other bytes. + 2. A tilde sorts before anything, even an empty string. + + In addition to the version sort rules, the following strings have + special priority and sort before all other strings (listed in order): + + 1. The empty string. + 2. ".". + 3. "..". + 4. Strings starting with "." sort before other strings. + + Before comparing two strings where both begin with non-".", + or where both begin with "." but neither is "." or "..", + suffixes matching the C-locale extended regular expression + (\.[A-Za-z~][A-Za-z0-9~]*)*$ are removed and the strings compared + without them, using version sort without special priority; + if they do not compare equal, this comparison result is used and + the suffixes are effectively ignored. Otherwise, the entire + strings are compared using version sort. + + This function is intended to be a replacement for strverscmp. */ +int filevercmp (char const *a, char const *b) _GL_ATTRIBUTE_PURE; + +/* Like filevercmp, except compare the byte arrays A (of length ALEN) + and B (of length BLEN) so that A and B can contain '\0', which + sorts just before '\1'. But if ALEN is -1 treat A as a string + terminated by '\0', and similarly for BLEN. */ +int filenvercmp (char const *a, ptrdiff_t alen, char const *b, ptrdiff_t blen) + _GL_ATTRIBUTE_PURE; + +#endif /* FILEVERCMP_H */ |