1 /* uudecode.c - uudecode / base64 decode
2 *
3 * Copyright 2013 Erich Plondke <toybox@erich.wreck.org>
4 *
5 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/uudecode.html
6
7 USE_UUDECODE(NEWTOY(uudecode, ">1o:", TOYFLAG_USR|TOYFLAG_BIN|TOYFLAG_UMASK))
8
9 config UUDECODE
10 bool "uudecode"
11 default y
12 help
13 usage: uudecode [-o OUTFILE] [INFILE]
14
15 Decode file from stdin (or INFILE).
16
17 -o Write to OUTFILE instead of filename in header
18 */
19
20 #define FOR_uudecode
21 #include "toys.h"
22
GLOBALS(char * o;)23 GLOBALS(
24 char *o;
25 )
26
27 void uudecode_main(void)
28 {
29 int ifd = 0, ofd, idx = 0, m = m;
30 char *line = 0, mode[16],
31 *class[] = {"begin%*[ ]%15s%*[ ]%n", "begin-base64%*[ ]%15s%*[ ]%n"};
32
33 if (toys.optc) ifd = xopenro(*toys.optargs);
34
35 while (!idx) {
36 free(line);
37 if (!(line = get_line(ifd))) error_exit("bad EOF");
38 for (m=0; m < 2; m++) {
39 sscanf(line, class[m], mode, &idx);
40 if (idx) break;
41 }
42 }
43
44 if (TT.o && !strcmp(TT.o, "-")) ofd = 1;
45 else ofd = xcreate(TT.o ? TT.o : line+idx, O_WRONLY|O_CREAT|O_TRUNC,
46 string_to_mode(mode, 0777^toys.old_umask));
47
48 for(;;) {
49 char *in, *out;
50 int olen;
51
52 free(line);
53 if (m == 2 || !(line = get_line(ifd))) break;
54 if (!strcmp(line, m ? "====" : "end")) {
55 m = 2;
56 continue;
57 }
58
59 olen = 0;
60 in = out = line;
61 if (!m) olen = (*(in++) - 32) & 0x3f;
62
63 for (;;) {
64 int i = 0, x = 0, len = 4;
65 char c = 0;
66
67 if (!m) {
68 if (olen < 1) break;
69 if (olen < 3) len = olen + 1;
70 }
71
72 while (i < len) {
73 if (!(c = *(in++))) goto line_done;
74
75 if (m) {
76 if (c == '=') {
77 len--;
78 continue;
79 } else if (len != 4) break;
80
81 if (c >= 'A' && c <= 'Z') c -= 'A';
82 else if (c >= 'a' && c <= 'z') c += 26 - 'a';
83 else if (c >= '0' && c <= '9') c += 52 - '0';
84 else if (c == '+') c = 62;
85 else if (c == '/') c = 63;
86 else continue;
87 } else c = (c - 32) & 0x3f;
88
89 x |= c << (6*(3-i));
90
91 if (i && i < len) {
92 *(out++) = (x>>(8*(3-i))) & 0xff;
93 olen--;
94 }
95 i++;
96 }
97
98 if (i && i!=len) error_exit("bad %s", line);
99 }
100 line_done:
101 xwrite(ofd, line, out-line);
102 }
103
104 if (CFG_TOYBOX_FREE) {
105 if (ifd) close(ifd);
106 close(ofd);
107 }
108 }
109