Mon, 27 Jul 2020 17:19:56 +0200
adds option to compute individual sums
1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 * Copyright 2018 Mike Becker. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
27 #include "bfile_heuristics.h"
28 #include <ctype.h>
30 bfile_heuristics_t *new_bfile_heuristics_t() {
31 bfile_heuristics_t *ret = malloc(sizeof(bfile_heuristics_t));
32 ret->level = BFILE_MEDIUM_ACCURACY;
33 bfile_reset(ret);
34 return ret;
35 }
37 void destroy_bfile_heuristics_t(bfile_heuristics_t *def) {
38 free(def);
39 }
41 void bfile_reset(bfile_heuristics_t *def) {
42 def->bcount = 0;
43 def->tcount = 0;
44 }
46 bool bfile_check(bfile_heuristics_t *def, int next_char) {
47 bool ret = false;
48 if (def->level != BFILE_IGNORE) {
49 def->tcount++;
50 if (!isprint(next_char) && !isspace(next_char)) {
51 def->bcount++;
52 }
54 if (def->tcount > 1) { /* empty files are text files */
55 switch (def->level) {
56 case BFILE_LOW_ACCURACY:
57 if (def->tcount > 15 || next_char == EOF) {
58 ret = (1.0*def->bcount)/def->tcount > 0.32;
59 }
60 break;
61 case BFILE_HIGH_ACCURACY:
62 if (def->tcount > 500 || next_char == EOF) {
63 ret = (1.0*def->bcount)/def->tcount > 0.1;
64 }
65 break;
66 default: /* BFILE_MEDIUM_ACCURACY */
67 if (def->tcount > 100 || next_char == EOF) {
68 ret = (1.0*def->bcount)/def->tcount > 0.1;
69 }
70 break;
71 }
72 }
73 }
75 return ret;
76 }