fltk/src/numericsort.c

131 lines
3.6 KiB
C

/*
* Numeric sorting routine for the Fast Light Tool Kit (FLTK).
*
* Copyright 1998-2018 by Bill Spitzak and others.
*
* This library is free software. Distribution and use rights are outlined in
* the file "COPYING" which should have been included with this file. If this
* file is missing or damaged, see the license at:
*
* https://www.fltk.org/COPYING.php
*
* Please see the following page on how to report bugs and issues:
*
* https://www.fltk.org/bugs.php
*/
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <FL/platform_types.h>
#include <FL/filename.H>
#include <FL/fl_utf8.h>
/**
\file numericsort.c
*/
/*
numericsort() - Compare two directory entries, possibly with a
case-insensitive comparison...
*/
static int numericsort(struct dirent **A, struct dirent **B, int cs) {
const char* a = (*A)->d_name;
const char* b = (*B)->d_name;
int len_a, len_b;
const char *end_a = a + strlen(a);
const char *end_b = b + strlen(b);
unsigned UTF_A, UTF_B;
int ret = 0;
while (1) {
UTF_A = fl_utf8decode(a, end_a, &len_a);
a += len_a;
UTF_B = fl_utf8decode(b, end_b, &len_b);
b += len_b;
if (UTF_A <= 255 && UTF_B <= 255 && isdigit(UTF_A) && isdigit(UTF_B)) {
int diff,magdiff;
while (UTF_A == '0') {UTF_A = fl_utf8decode(a, end_a, &len_a); a += len_a;}
while (UTF_B == '0') {UTF_B = fl_utf8decode(b, end_b, &len_b); b += len_b;}
while (UTF_A <= 255 && isdigit(UTF_A) && UTF_A == UTF_B) {
UTF_A = fl_utf8decode(a, end_a, &len_a); a += len_a;
UTF_B = fl_utf8decode(b, end_b, &len_b); b += len_b;
}
diff = (UTF_A <= 255 && UTF_B <= 255 && isdigit(UTF_A) && isdigit(UTF_B)) ? UTF_A - UTF_B : 0;
magdiff = 0;
while (UTF_A <= 255 && isdigit(UTF_A)) {
magdiff++;
UTF_A = fl_utf8decode(a, end_a, &len_a); a += len_a;
}
while (UTF_B <= 255 && isdigit(UTF_B)) {
magdiff--;
UTF_B = fl_utf8decode(b, end_b, &len_b); b += len_b;
}
if (magdiff) {ret = magdiff; break;} /* compare # of significant digits */
if (diff) {ret = diff; break;} /* compare first non-zero digit */
} else {
if (cs) {
/* compare case-sensitive */
if ((ret = UTF_A - UTF_B)) break;
} else {
/* compare case-insensitive */
if ((ret = fl_tolower(UTF_A) - fl_tolower(UTF_B))) break;
}
if (a >= end_a) break;
//a++; b++;
}
}
if (!ret) return 0;
else return (ret < 0) ? -1 : 1;
}
/**
Compares directory entries alphanumerically (case-insensitive).
\note This comparison is UTF-8 aware.
\see fl_numericsort()
*/
int fl_casenumericsort(struct dirent **A, struct dirent **B) {
return numericsort(A, B, 0);
}
/**
Compares directory entries alphanumerically (case-sensitive).
Numbers are compared without sign, i.e. "-" is not taken as a sign of
following numerical values. The following list of files would be in
ascending order (examples are ASCII and numbers only for simplicity):
-# 1zzz.txt
-# 2xxx.txt
-# 19uuu.txt
-# 100aaa.txt
-# file1z.txt
-# file5a.txt
-# file5z.txt
-# file30z.txt
-# file200a.txt
-# temp+5.txt ('+' is lexically lower than '-')
-# temp-5.txt ('-' is not a sign)
-# temp-100.txt (100 is bigger than 5, no sign)
\param[in] A first directory entry
\param[in] B second directory entry
\returns comparison result (-1, 0, or +1)
\retval -1 A \< B
\retval 0 A == B
\retval +1 A \> B
\note This comparison is UTF-8 aware.
\see fl_casenumericsort()
*/
int fl_numericsort(struct dirent **A, struct dirent **B) {
return numericsort(A, B, 1);
}