Thu, 20 Oct 2011 17:29:23 +0200
completed binary file heuristics
1 /*
2 * bfile_heuristics.c
3 *
4 * Created on: 20.10.2011
5 * Author: Mike
6 */
8 #include "bfile_heuristics.h"
9 #include <ctype.h>
11 bfile_heuristics_t *new_bfile_heuristics_t() {
12 bfile_heuristics_t *ret = malloc(sizeof(bfile_heuristics_t));
13 ret->level = BFILE_MEDIUM_ACCURACY;
14 bfile_reset(ret);
15 return ret;
16 }
18 void destroy_bfile_heuristics_t(bfile_heuristics_t *def) {
19 free(def);
20 }
22 void bfile_reset(bfile_heuristics_t *def) {
23 def->bcount = 0;
24 def->tcount = 0;
25 }
27 bool bfile_check(bfile_heuristics_t *def, int next_char) {
28 bool ret = false;
29 if (def->level != BFILE_IGNORE) {
30 def->tcount++;
31 if (!isprint(next_char) && !isspace(next_char)) {
32 def->bcount++;
33 }
35 switch (def->level) {
36 case BFILE_LOW_ACCURACY:
37 if (def->tcount > 15 || next_char == EOF) {
38 ret = (1.0*def->bcount)/def->tcount > 0.32;
39 }
40 break;
41 case BFILE_HIGH_ACCURACY:
42 if (def->tcount > 500 || next_char == EOF) {
43 ret = (1.0*def->bcount)/def->tcount > 0.1;
44 }
45 break;
46 default: /* BFILE_MEDIUM_ACCURACY */
47 if (def->tcount > 100 || next_char == EOF) {
48 ret = (1.0*def->bcount)/def->tcount > 0.1;
49 }
50 }
51 }
53 return ret;
54 }