Contents of /trunk/mkinitrd-magellan/busybox/miscutils/rx.c
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Sun May 30 11:32:42 2010 UTC (14 years, 4 months ago) by niro
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File size: 6111 byte(s)
Sun May 30 11:32:42 2010 UTC (14 years, 4 months ago) by niro
File MIME type: text/plain
File size: 6111 byte(s)
-updated to busybox-1.16.1 and enabled blkid/uuid support in default config
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * Copyright: Copyright (C) 2001, Hewlett-Packard Company |
4 | * Author: Christopher Hoover <ch@hpl.hp.com> |
5 | * Description: xmodem functionality for uploading of kernels |
6 | * and the like |
7 | * Created at: Thu Dec 20 01:58:08 PST 2001 |
8 | * |
9 | * xmodem functionality for uploading of kernels and the like |
10 | * |
11 | * Copyright (C) 2001 Hewlett-Packard Laboratories |
12 | * |
13 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
14 | * |
15 | * This was originally written for blob and then adapted for busybox. |
16 | */ |
17 | |
18 | #include "libbb.h" |
19 | |
20 | #define SOH 0x01 |
21 | #define STX 0x02 |
22 | #define EOT 0x04 |
23 | #define ACK 0x06 |
24 | #define NAK 0x15 |
25 | #define BS 0x08 |
26 | #define PAD 0x1A |
27 | |
28 | /* |
29 | Cf: |
30 | http://www.textfiles.com/apple/xmodem |
31 | http://www.phys.washington.edu/~belonis/xmodem/docxmodem.txt |
32 | http://www.phys.washington.edu/~belonis/xmodem/docymodem.txt |
33 | http://www.phys.washington.edu/~belonis/xmodem/modmprot.col |
34 | */ |
35 | |
36 | #define TIMEOUT 1 |
37 | #define TIMEOUT_LONG 10 |
38 | #define MAXERRORS 10 |
39 | |
40 | #define read_fd STDIN_FILENO |
41 | #define write_fd STDOUT_FILENO |
42 | |
43 | static int read_byte(unsigned timeout) |
44 | { |
45 | unsigned char buf; |
46 | int n; |
47 | |
48 | alarm(timeout); |
49 | /* NOT safe_read! We want ALRM to interrupt us */ |
50 | n = read(read_fd, &buf, 1); |
51 | alarm(0); |
52 | if (n == 1) |
53 | return buf; |
54 | return -1; |
55 | } |
56 | |
57 | static int receive(/*int read_fd, */int file_fd) |
58 | { |
59 | unsigned char blockBuf[1024]; |
60 | unsigned blockLength = 0; |
61 | unsigned errors = 0; |
62 | unsigned wantBlockNo = 1; |
63 | unsigned length = 0; |
64 | int do_crc = 1; |
65 | char reply_char; |
66 | unsigned timeout = TIMEOUT_LONG; |
67 | |
68 | /* Flush pending input */ |
69 | tcflush(read_fd, TCIFLUSH); |
70 | |
71 | /* Ask for CRC; if we get errors, we will go with checksum */ |
72 | reply_char = 'C'; |
73 | full_write(write_fd, &reply_char, 1); |
74 | |
75 | for (;;) { |
76 | int blockBegin; |
77 | int blockNo, blockNoOnesCompl; |
78 | int cksum_or_crc; |
79 | int expected; |
80 | int i, j; |
81 | |
82 | blockBegin = read_byte(timeout); |
83 | if (blockBegin < 0) |
84 | goto timeout; |
85 | |
86 | /* If last block, remove padding */ |
87 | if (blockBegin == EOT) { |
88 | /* Data blocks can be padded with ^Z characters */ |
89 | /* This code tries to detect and remove them */ |
90 | if (blockLength >= 3 |
91 | && blockBuf[blockLength - 1] == PAD |
92 | && blockBuf[blockLength - 2] == PAD |
93 | && blockBuf[blockLength - 3] == PAD |
94 | ) { |
95 | while (blockLength |
96 | && blockBuf[blockLength - 1] == PAD |
97 | ) { |
98 | blockLength--; |
99 | } |
100 | } |
101 | } |
102 | /* Write previously received block */ |
103 | if (blockLength) { |
104 | errno = 0; |
105 | if (full_write(file_fd, blockBuf, blockLength) != blockLength) { |
106 | bb_perror_msg("can't write to file"); |
107 | goto fatal; |
108 | } |
109 | } |
110 | |
111 | timeout = TIMEOUT; |
112 | reply_char = NAK; |
113 | |
114 | switch (blockBegin) { |
115 | case SOH: |
116 | case STX: |
117 | break; |
118 | case EOT: |
119 | reply_char = ACK; |
120 | full_write(write_fd, &reply_char, 1); |
121 | return length; |
122 | default: |
123 | goto error; |
124 | } |
125 | |
126 | /* Block no */ |
127 | blockNo = read_byte(TIMEOUT); |
128 | if (blockNo < 0) |
129 | goto timeout; |
130 | |
131 | /* Block no, in one's complement form */ |
132 | blockNoOnesCompl = read_byte(TIMEOUT); |
133 | if (blockNoOnesCompl < 0) |
134 | goto timeout; |
135 | |
136 | if (blockNo != (255 - blockNoOnesCompl)) { |
137 | bb_error_msg("bad block ones compl"); |
138 | goto error; |
139 | } |
140 | |
141 | blockLength = (blockBegin == SOH) ? 128 : 1024; |
142 | |
143 | for (i = 0; i < blockLength; i++) { |
144 | int cc = read_byte(TIMEOUT); |
145 | if (cc < 0) |
146 | goto timeout; |
147 | blockBuf[i] = cc; |
148 | } |
149 | |
150 | if (do_crc) { |
151 | cksum_or_crc = read_byte(TIMEOUT); |
152 | if (cksum_or_crc < 0) |
153 | goto timeout; |
154 | cksum_or_crc = (cksum_or_crc << 8) | read_byte(TIMEOUT); |
155 | if (cksum_or_crc < 0) |
156 | goto timeout; |
157 | } else { |
158 | cksum_or_crc = read_byte(TIMEOUT); |
159 | if (cksum_or_crc < 0) |
160 | goto timeout; |
161 | } |
162 | |
163 | if (blockNo == ((wantBlockNo - 1) & 0xff)) { |
164 | /* a repeat of the last block is ok, just ignore it. */ |
165 | /* this also ignores the initial block 0 which is */ |
166 | /* meta data. */ |
167 | goto next; |
168 | } |
169 | if (blockNo != (wantBlockNo & 0xff)) { |
170 | bb_error_msg("unexpected block no, 0x%08x, expecting 0x%08x", blockNo, wantBlockNo); |
171 | goto error; |
172 | } |
173 | |
174 | expected = 0; |
175 | if (do_crc) { |
176 | for (i = 0; i < blockLength; i++) { |
177 | expected = expected ^ blockBuf[i] << 8; |
178 | for (j = 0; j < 8; j++) { |
179 | if (expected & 0x8000) |
180 | expected = (expected << 1) ^ 0x1021; |
181 | else |
182 | expected = (expected << 1); |
183 | } |
184 | } |
185 | expected &= 0xffff; |
186 | } else { |
187 | for (i = 0; i < blockLength; i++) |
188 | expected += blockBuf[i]; |
189 | expected &= 0xff; |
190 | } |
191 | if (cksum_or_crc != expected) { |
192 | bb_error_msg(do_crc ? "crc error, expected 0x%04x, got 0x%04x" |
193 | : "checksum error, expected 0x%02x, got 0x%02x", |
194 | expected, cksum_or_crc); |
195 | goto error; |
196 | } |
197 | |
198 | wantBlockNo++; |
199 | length += blockLength; |
200 | next: |
201 | errors = 0; |
202 | reply_char = ACK; |
203 | full_write(write_fd, &reply_char, 1); |
204 | continue; |
205 | error: |
206 | timeout: |
207 | errors++; |
208 | if (errors == MAXERRORS) { |
209 | /* Abort */ |
210 | |
211 | /* If were asking for crc, try again w/o crc */ |
212 | if (reply_char == 'C') { |
213 | reply_char = NAK; |
214 | errors = 0; |
215 | do_crc = 0; |
216 | goto timeout; |
217 | } |
218 | bb_error_msg("too many errors; giving up"); |
219 | fatal: |
220 | /* 5 CAN followed by 5 BS. Don't try too hard... */ |
221 | safe_write(write_fd, "\030\030\030\030\030\010\010\010\010\010", 10); |
222 | return -1; |
223 | } |
224 | |
225 | /* Flush pending input */ |
226 | tcflush(read_fd, TCIFLUSH); |
227 | |
228 | full_write(write_fd, &reply_char, 1); |
229 | } /* for (;;) */ |
230 | } |
231 | |
232 | static void sigalrm_handler(int UNUSED_PARAM signum) |
233 | { |
234 | } |
235 | |
236 | int rx_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
237 | int rx_main(int argc UNUSED_PARAM, char **argv) |
238 | { |
239 | struct termios tty, orig_tty; |
240 | int termios_err; |
241 | int file_fd; |
242 | int n; |
243 | |
244 | /* Disabled by vda: |
245 | * why we can't receive from stdin? Why we *require* |
246 | * controlling tty?? */ |
247 | /*read_fd = xopen(CURRENT_TTY, O_RDWR);*/ |
248 | file_fd = xopen(single_argv(argv), O_RDWR|O_CREAT|O_TRUNC); |
249 | |
250 | termios_err = tcgetattr(read_fd, &tty); |
251 | if (termios_err == 0) { |
252 | orig_tty = tty; |
253 | cfmakeraw(&tty); |
254 | tcsetattr(read_fd, TCSAFLUSH, &tty); |
255 | } |
256 | |
257 | /* No SA_RESTART: we want ALRM to interrupt read() */ |
258 | signal_no_SA_RESTART_empty_mask(SIGALRM, sigalrm_handler); |
259 | |
260 | n = receive(file_fd); |
261 | |
262 | if (termios_err == 0) |
263 | tcsetattr(read_fd, TCSAFLUSH, &orig_tty); |
264 | if (ENABLE_FEATURE_CLEAN_UP) |
265 | close(file_fd); |
266 | fflush_stdout_and_exit(n >= 0); |
267 | } |