6e182d98 |
1 | #include <stdio.h> |
2 | #include <stdlib.h> |
3 | #include <string.h> |
4 | |
5 | #include "tweak.h" |
6 | |
7 | static DFA dfa = NULL; |
8 | static char *tmp = NULL; |
9 | static int dfa_size = 0, dfa_len = 0; |
10 | |
11 | DFA build_dfa (char *pattern, int len) { |
12 | int i, j, k, b; |
13 | |
14 | if (dfa_size < len) { |
15 | dfa_size = len; |
16 | dfa = (dfa ? realloc(dfa, dfa_size * sizeof(*dfa)) : |
17 | malloc(dfa_size * sizeof(*dfa))); |
18 | if (!dfa) |
19 | return NULL; |
20 | tmp = (tmp ? realloc(tmp, dfa_size) : malloc(dfa_size)); |
21 | if (!tmp) |
22 | return NULL; |
23 | } |
24 | |
25 | memcpy (tmp, pattern, len); |
26 | |
27 | for (i=len; i-- ;) { |
28 | j = i+1; |
29 | for (b=0; b<256; b++) { |
30 | dfa[i][b] = 0; |
31 | if (memchr(pattern, b, len)) { |
32 | tmp[j-1] = b; |
33 | for (k=1; k<=j; k++) |
34 | if (!memcmp(tmp+j-k, pattern, k)) |
35 | dfa[i][b] = k; |
36 | } |
37 | } |
38 | } |
39 | dfa_len = len; |
40 | return dfa; |
41 | } |
42 | |
43 | DFA last_dfa (void) { |
44 | return dfa; |
45 | } |
46 | |
47 | int last_len (void) { |
48 | return dfa_len; |
49 | } |