Contents of /tags/mkinitrd-6_1_6/busybox/coreutils/uudecode.c
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Wed Aug 5 19:21:45 2009 UTC (15 years, 1 month ago) by niro
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Wed Aug 5 19:21:45 2009 UTC (15 years, 1 month ago) by niro
File MIME type: text/plain
File size: 5184 byte(s)
tagged 'mkinitrd-6_1_6'
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * Copyright 2003, Glenn McGrath |
4 | * |
5 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
6 | * |
7 | * Based on specification from |
8 | * http://www.opengroup.org/onlinepubs/007904975/utilities/uuencode.html |
9 | * |
10 | * Bugs: the spec doesn't mention anything about "`\n`\n" prior to the |
11 | * "end" line |
12 | */ |
13 | |
14 | |
15 | #include "libbb.h" |
16 | |
17 | static void read_stduu(FILE *src_stream, FILE *dst_stream) |
18 | { |
19 | char *line; |
20 | |
21 | while ((line = xmalloc_fgetline(src_stream)) != NULL) { |
22 | int encoded_len, str_len; |
23 | char *line_ptr, *dst; |
24 | |
25 | if (strcmp(line, "end") == 0) { |
26 | return; /* the only non-error exit */ |
27 | } |
28 | |
29 | line_ptr = line; |
30 | while (*line_ptr) { |
31 | *line_ptr = (*line_ptr - 0x20) & 0x3f; |
32 | line_ptr++; |
33 | } |
34 | str_len = line_ptr - line; |
35 | |
36 | encoded_len = line[0] * 4 / 3; |
37 | /* Check that line is not too short. (we tolerate |
38 | * overly _long_ line to accomodate possible extra '`'). |
39 | * Empty line case is also caught here. */ |
40 | if (str_len <= encoded_len) { |
41 | break; /* go to bb_error_msg_and_die("short file"); */ |
42 | } |
43 | if (encoded_len <= 0) { |
44 | /* Ignore the "`\n" line, why is it even in the encode file ? */ |
45 | free(line); |
46 | continue; |
47 | } |
48 | if (encoded_len > 60) { |
49 | bb_error_msg_and_die("line too long"); |
50 | } |
51 | |
52 | dst = line; |
53 | line_ptr = line + 1; |
54 | do { |
55 | /* Merge four 6 bit chars to three 8 bit chars */ |
56 | *dst++ = line_ptr[0] << 2 | line_ptr[1] >> 4; |
57 | encoded_len--; |
58 | if (encoded_len == 0) { |
59 | break; |
60 | } |
61 | |
62 | *dst++ = line_ptr[1] << 4 | line_ptr[2] >> 2; |
63 | encoded_len--; |
64 | if (encoded_len == 0) { |
65 | break; |
66 | } |
67 | |
68 | *dst++ = line_ptr[2] << 6 | line_ptr[3]; |
69 | line_ptr += 4; |
70 | encoded_len -= 2; |
71 | } while (encoded_len > 0); |
72 | fwrite(line, 1, dst - line, dst_stream); |
73 | free(line); |
74 | } |
75 | bb_error_msg_and_die("short file"); |
76 | } |
77 | |
78 | static void read_base64(FILE *src_stream, FILE *dst_stream) |
79 | { |
80 | int term_count = 1; |
81 | |
82 | while (1) { |
83 | char translated[4]; |
84 | int count = 0; |
85 | |
86 | while (count < 4) { |
87 | char *table_ptr; |
88 | int ch; |
89 | |
90 | /* Get next _valid_ character. |
91 | * global vector bb_uuenc_tbl_base64[] contains this string: |
92 | * "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=\n" |
93 | */ |
94 | do { |
95 | ch = fgetc(src_stream); |
96 | if (ch == EOF) { |
97 | bb_error_msg_and_die("short file"); |
98 | } |
99 | table_ptr = strchr(bb_uuenc_tbl_base64, ch); |
100 | } while (table_ptr == NULL); |
101 | |
102 | /* Convert encoded character to decimal */ |
103 | ch = table_ptr - bb_uuenc_tbl_base64; |
104 | |
105 | if (*table_ptr == '=') { |
106 | if (term_count == 0) { |
107 | translated[count] = '\0'; |
108 | break; |
109 | } |
110 | term_count++; |
111 | } else if (*table_ptr == '\n') { |
112 | /* Check for terminating line */ |
113 | if (term_count == 5) { |
114 | return; |
115 | } |
116 | term_count = 1; |
117 | continue; |
118 | } else { |
119 | translated[count] = ch; |
120 | count++; |
121 | term_count = 0; |
122 | } |
123 | } |
124 | |
125 | /* Merge 6 bit chars to 8 bit */ |
126 | if (count > 1) { |
127 | fputc(translated[0] << 2 | translated[1] >> 4, dst_stream); |
128 | } |
129 | if (count > 2) { |
130 | fputc(translated[1] << 4 | translated[2] >> 2, dst_stream); |
131 | } |
132 | if (count > 3) { |
133 | fputc(translated[2] << 6 | translated[3], dst_stream); |
134 | } |
135 | } |
136 | } |
137 | |
138 | int uudecode_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
139 | int uudecode_main(int argc UNUSED_PARAM, char **argv) |
140 | { |
141 | FILE *src_stream; |
142 | char *outname = NULL; |
143 | char *line; |
144 | |
145 | opt_complementary = "?1"; /* 1 argument max */ |
146 | getopt32(argv, "o:", &outname); |
147 | argv += optind; |
148 | |
149 | if (!*argv) |
150 | *--argv = (char*)"-"; |
151 | src_stream = xfopen_stdin(*argv); |
152 | |
153 | /* Search for the start of the encoding */ |
154 | while ((line = xmalloc_fgetline(src_stream)) != NULL) { |
155 | void (*decode_fn_ptr)(FILE *src, FILE *dst); |
156 | char *line_ptr; |
157 | FILE *dst_stream; |
158 | int mode; |
159 | |
160 | if (strncmp(line, "begin-base64 ", 13) == 0) { |
161 | line_ptr = line + 13; |
162 | decode_fn_ptr = read_base64; |
163 | } else if (strncmp(line, "begin ", 6) == 0) { |
164 | line_ptr = line + 6; |
165 | decode_fn_ptr = read_stduu; |
166 | } else { |
167 | free(line); |
168 | continue; |
169 | } |
170 | |
171 | /* begin line found. decode and exit */ |
172 | mode = bb_strtou(line_ptr, NULL, 8); |
173 | if (outname == NULL) { |
174 | outname = strchr(line_ptr, ' '); |
175 | if ((outname == NULL) || (*outname == '\0')) { |
176 | break; |
177 | } |
178 | outname++; |
179 | } |
180 | dst_stream = stdout; |
181 | if (NOT_LONE_DASH(outname)) { |
182 | dst_stream = xfopen_for_write(outname); |
183 | fchmod(fileno(dst_stream), mode & (S_IRWXU | S_IRWXG | S_IRWXO)); |
184 | } |
185 | free(line); |
186 | decode_fn_ptr(src_stream, dst_stream); |
187 | /* fclose_if_not_stdin(src_stream); - redundant */ |
188 | return EXIT_SUCCESS; |
189 | } |
190 | bb_error_msg_and_die("no 'begin' line"); |
191 | } |
192 | |
193 | /* Test script. |
194 | Put this into an empty dir with busybox binary, an run. |
195 | |
196 | #!/bin/sh |
197 | test -x busybox || { echo "No ./busybox?"; exit; } |
198 | ln -sf busybox uudecode |
199 | ln -sf busybox uuencode |
200 | >A_null |
201 | echo -n A >A |
202 | echo -n AB >AB |
203 | echo -n ABC >ABC |
204 | echo -n ABCD >ABCD |
205 | echo -n ABCDE >ABCDE |
206 | echo -n ABCDEF >ABCDEF |
207 | cat busybox >A_bbox |
208 | for f in A*; do |
209 | echo uuencode $f |
210 | ./uuencode $f <$f >u_$f |
211 | ./uuencode -m $f <$f >m_$f |
212 | done |
213 | mkdir unpk_u unpk_m 2>/dev/null |
214 | for f in u_*; do |
215 | ./uudecode <$f -o unpk_u/${f:2} |
216 | diff -a ${f:2} unpk_u/${f:2} >/dev/null 2>&1 |
217 | echo uudecode $f: $? |
218 | done |
219 | for f in m_*; do |
220 | ./uudecode <$f -o unpk_m/${f:2} |
221 | diff -a ${f:2} unpk_m/${f:2} >/dev/null 2>&1 |
222 | echo uudecode $f: $? |
223 | done |
224 | */ |