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 = xopen(*toys.optargs, O_RDONLY);
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 ofd = xcreate(TT.o ? TT.o : line+idx, O_WRONLY|O_CREAT|O_TRUNC,
45 string_to_mode(mode, 0777^toys.old_umask));
46
47 for(;;) {
48 char *in, *out;
49 int olen;
50
51 free(line);
52 if (m == 2 || !(line = get_line(ifd))) break;
53 if (!strcmp(line, m ? "====" : "end")) {
54 m = 2;
55 continue;
56 }
57
58 olen = 0;
59 in = out = line;
60 if (!m) olen = (*(in++) - 32) & 0x3f;
61
62 for (;;) {
63 int i = 0, x = 0, len = 4;
64 char c = 0;
65
66 if (!m) {
67 if (olen < 1) break;
68 if (olen < 3) len = olen + 1;
69 }
70
71 while (i < len) {
72 if (!(c = *(in++))) goto line_done;
73
74 if (m) {
75 if (c == '=') {
76 len--;
77 continue;
78 } else if (len != 4) break;
79
80 if (c >= 'A' && c <= 'Z') c -= 'A';
81 else if (c >= 'a' && c <= 'z') c += 26 - 'a';
82 else if (c >= '0' && c <= '9') c += 52 - '0';
83 else if (c == '+') c = 62;
84 else if (c == '/') c = 63;
85 else continue;
86 } else c = (c - 32) & 0x3f;
87
88 x |= c << (6*(3-i));
89
90 if (i && i < len) {
91 *(out++) = (x>>(8*(3-i))) & 0xff;
92 olen--;
93 }
94 i++;
95 }
96
97 if (i && i!=len) error_exit("bad %s", line);
98 }
99 line_done:
100 xwrite(ofd, line, out-line);
101 }
102
103 if (CFG_TOYBOX_FREE) {
104 if (ifd) close(ifd);
105 close(ofd);
106 }
107 }
108