AmendHub

--- strnatcmp.c Wed Oct 13 17:21:09 2021 +++ strnatcmp.c Fri Jan 1 18:12:15 1904 @@ -1,157 +0,0 @@ -/* -*- mode: c; c-file-style: "k&r" -*- - - strnatcmp.c -- Perform 'natural order' comparisons of strings in C. - Copyright (C) 2000, 2004 by Martin Pool <mbp sourcefrog net> - - This software is provided 'as-is', without any express or implied - warranty. In no event will the authors be held liable for any damages - arising from the use of this software. - - Permission is granted to anyone to use this software for any purpose, - including commercial applications, and to alter it and redistribute it - freely, subject to the following restrictions: - - 1. The origin of this software must not be misrepresented; you must not - claim that you wrote the original software. If you use this software - in a product, an acknowledgment in the product documentation would be - appreciated but is not required. - 2. Altered source versions must be plainly marked as such, and must not be - misrepresented as being the original software. - 3. This notice may not be removed or altered from any source distribution. -*/ - - -/* partial change history: - * - * 2004-10-10 mbp: Lift out character type dependencies into macros. - * - * Eric Sosman pointed out that ctype functions take a parameter whose - * value must be that of an unsigned int, even on platforms that have - * negative chars in their default char type. - * - * 2021-10-13 jcs: Modified to compile in THINK C 5 - */ - -#include <stddef.h> /* size_t */ -#include <ctype.h> - -#include "util.h" - -int compare_right(char const *a, char const *b); - -int -compare_right(char const *a, char const *b) -{ - int bias = 0; - - /* The longest run of digits wins. That aside, the greatest - value wins, but we can't know that it will until we've scanned - both numbers to know that they have the same magnitude, so we - remember it in BIAS. */ - for (;; a++, b++) { - if (!isdigit((unsigned char)*a) && !isdigit((unsigned char)*b)) - return bias; - if (!isdigit((unsigned char)*a)) - return -1; - if (!isdigit((unsigned char)*b)) - return +1; - if (*a < *b) { - if (!bias) - bias = -1; - } else if (*a > *b) { - if (!bias) - bias = +1; - } else if (!*a && !*b) - return bias; - } - - return 0; -} - - -static int -compare_left(char const *a, char const *b) -{ - /* Compare two left-aligned numbers: the first to have a - different value wins. */ - for (;; a++, b++) { - if (!isdigit((unsigned char)*a) && !isdigit((unsigned char)*b)) - return 0; - if (!isdigit((unsigned char)*a)) - return -1; - if (!isdigit((unsigned char)*b)) - return +1; - if (*a < *b) - return -1; - if (*a > *b) - return +1; - } - - return 0; -} - - -static int -strnatcmp0(char const *a, char const *b, int fold_case) -{ - int ai, bi; - char ca, cb; - int fractional, result; - - ai = bi = 0; - while (1) { - ca = a[ai]; cb = b[bi]; - - /* skip over leading spaces or zeros */ - while (isspace((unsigned char)ca)) - ca = a[++ai]; - - while (isspace((unsigned char)cb)) - cb = b[++bi]; - - /* process run of digits */ - if (isdigit((unsigned char)ca) && isdigit((unsigned char)cb)) { - fractional = (ca == '0' || cb == '0'); - - if (fractional) { - if ((result = compare_left(a+ai, b+bi)) != 0) - return result; - } else { - if ((result = compare_right(a+ai, b+bi)) != 0) - return result; - } - } - - if (!ca && !cb) { - /* The strings compare the same. Perhaps the caller - will want to call strcmp to break the tie. */ - return 0; - } - - if (fold_case) { - ca = toupper((unsigned char)ca); - cb = toupper((unsigned char)cb); - } - - if (ca < cb) - return -1; - - if (ca > cb) - return +1; - - ++ai; ++bi; - } -} - - -int -strnatcmp(char const *a, char const *b) { - return strnatcmp0(a, b, 0); -} - - -/* Compare, recognizing numeric string and ignoring case. */ -int -strnatcasecmp(char const *a, char const *b) { - return strnatcmp0(a, b, 1); -}