miscutils/rx.c - codeaurora/busybox - Gitiles

 /*-------------------------------------------------------------------------
  * Filename:      xmodem.c
  * Version:       $Id: rx.c,v 1.2 2004/03/15 08:28:46 andersen Exp $
  * Copyright:     Copyright (C) 2001, Hewlett-Packard Company
  * Author:        Christopher Hoover <ch@hpl.hp.com>
  * Description:   xmodem functionality for uploading of kernels
  *                and the like
  * Created at:    Thu Dec 20 01:58:08 PST 2001
  *-----------------------------------------------------------------------*/
 /*
  * xmodem.c: xmodem functionality for uploading of kernels and
  *            the like
  *
  * Copyright (C) 2001 Hewlett-Packard Laboratories
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  *
  *
  * This was originally written for blob and then adapted for busybox.
  *
  */

 #include <stdlib.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <unistd.h>
 #include <errno.h>
 #include <termios.h>
 #include <signal.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <string.h>
 #include "busybox.h"


 #define SOH 0x01
 #define STX 0x02
 #define EOT 0x04
 #define ACK 0x06
 #define NAK 0x15
 #define CAN 0x18
 #define BS  0x08

 /*

 Cf:

   http://www.textfiles.com/apple/xmodem
   http://www.phys.washington.edu/~belonis/xmodem/docxmodem.txt
   http://www.phys.washington.edu/~belonis/xmodem/docymodem.txt
   http://www.phys.washington.edu/~belonis/xmodem/modmprot.col

 */

 #define TIMEOUT 1
 #define TIMEOUT_LONG 10
 #define MAXERRORS 10

 static inline void write_byte(int fd, char cc) {
 	write(fd, &cc, 1);
 }

 static inline void write_flush(int fd) {
 	tcdrain(fd);
 }

 static inline void read_flush(int fd) {
 	tcflush(fd, TCIFLUSH);
 }

 static int read_byte(int fd, unsigned int timeout) {
 	char buf[1];
 	int n;

 	alarm(timeout);

 	n = read(fd, &buf, 1);

 	alarm(0);

 	if (n == 1)
 		return buf[0] & 0xff;
 	else
 		return -1;
 }

 static int receive(char *error_buf, size_t error_buf_size,
 				   int ttyfd, int filefd)
 {
 	char blockBuf[1024];
 	unsigned int errors = 0;
 	unsigned int wantBlockNo = 1;
 	unsigned int length = 0;
 	int docrc = 1;
 	char nak = 'C';
 	unsigned int timeout = TIMEOUT_LONG;

 #define note_error(fmt,args...) \
 	snprintf(error_buf, error_buf_size, fmt,##args)

 	read_flush(ttyfd);

 	/* Ask for CRC; if we get errors, we will go with checksum */
 	write_byte(ttyfd, nak);
 	write_flush(ttyfd);

 	for (;;) {
 		int blockBegin;
 		int blockNo, blockNoOnesCompl;
 		int blockLength;
 		int cksum = 0;
 		int crcHi = 0;
 		int crcLo = 0;

 		blockBegin = read_byte(ttyfd, timeout);
 		if (blockBegin < 0)
 			goto timeout;

 		timeout = TIMEOUT;
 		nak = NAK;

 		switch (blockBegin) {
 		case SOH:
 		case STX:
 			break;

 		case EOT:
 			write_byte(ttyfd, ACK);
 			write_flush(ttyfd);
 			goto done;

 		default:
 			goto error;
 		}

 		/* block no */
 		blockNo = read_byte(ttyfd, TIMEOUT);
 		if (blockNo < 0)
 			goto timeout;

 		/* block no one's compliment */
 		blockNoOnesCompl = read_byte(ttyfd, TIMEOUT);
 		if (blockNoOnesCompl < 0)
 			goto timeout;

 		if (blockNo != (255 - blockNoOnesCompl)) {
 			note_error("bad block ones compl");
 			goto error;
 		}

 		blockLength = (blockBegin == SOH) ? 128 : 1024;

 		{
 			int i;

 			for (i = 0; i < blockLength; i++) {
 				int cc = read_byte(ttyfd, TIMEOUT);
 				if (cc < 0)
 					goto timeout;
 				blockBuf[i] = cc;
 			}
 		}

 		if (docrc) {
 			crcHi = read_byte(ttyfd, TIMEOUT);
 			if (crcHi < 0)
 				goto timeout;

 			crcLo = read_byte(ttyfd, TIMEOUT);
 			if (crcLo < 0)
 				goto timeout;
 		} else {
 			cksum = read_byte(ttyfd, TIMEOUT);
 			if (cksum < 0)
 				goto timeout;
 		}

 		if (blockNo == ((wantBlockNo - 1) & 0xff)) {
 			/* a repeat of the last block is ok, just ignore it. */
 			/* this also ignores the initial block 0 which is */
 			/* meta data. */
 			goto next;
 		} else if (blockNo != (wantBlockNo & 0xff)) {
 			note_error("unexpected block no, 0x%08x, expecting 0x%08x", blockNo, wantBlockNo);
 			goto error;
 		}

 		if (docrc) {
 			int crc = 0;
 			int i, j;
 			int expectedCrcHi;
 			int expectedCrcLo;

 			for (i = 0; i < blockLength; i++) {
 				crc = crc ^ (int) blockBuf[i] << 8;
 				for (j = 0; j < 8; j++)
 					if (crc & 0x8000)
 						crc = crc << 1 ^ 0x1021;
 					else
 						crc = crc << 1;
 			}

 			expectedCrcHi = (crc >> 8) & 0xff;
 			expectedCrcLo = crc & 0xff;

 			if ((crcHi != expectedCrcHi) ||
 			    (crcLo != expectedCrcLo)) {
 				note_error("crc error, expected 0x%02x 0x%02x, got 0x%02x 0x%02x", expectedCrcHi, expectedCrcLo, crcHi, crcLo);
 				goto error;
 			}
 		} else {
 			unsigned char expectedCksum = 0;
 			int i;

 			for (i = 0; i < blockLength; i++)
 				expectedCksum += blockBuf[i];

 			if (cksum != expectedCksum) {
 				note_error("checksum error, expected 0x%02x, got 0x%02x", expectedCksum, cksum);
 				goto error;
 			}
 		}

 		wantBlockNo++;
 		length += blockLength;

 		if (bb_full_write(filefd, blockBuf, blockLength) < 0) {
 			note_error("write to file failed: %m");
 			goto fatal;
 		}

 	next:
 		errors = 0;
 		write_byte(ttyfd, ACK);
 		write_flush(ttyfd);
 		continue;

 	error:
 	timeout:
 		errors++;
 		if (errors == MAXERRORS) {
 			/* Abort */
 			int i;

 			// if using crc, try again w/o crc
 			if (nak == 'C') {
 				nak = NAK;
 				errors = 0;
 				docrc = 0;
 				goto timeout;
 			}

 			note_error("too many errors; giving up");

 		fatal:
 			for (i = 0; i < 5; i ++)
 				write_byte(ttyfd, CAN);
 			for (i = 0; i < 5; i ++)
 				write_byte(ttyfd, BS);
 			write_flush(ttyfd);
 			return -1;
 		}

 		read_flush(ttyfd);
 		write_byte(ttyfd, nak);
 		write_flush(ttyfd);
 	}

  done:
 	return length;

 #undef note_error
 }

 static void sigalrm_handler(int signum)
 {
 }

 int rx_main(int argc, char **argv)
 {
 	char *fn;
 	int ttyfd, filefd;
 	struct termios tty, orig_tty;
 	struct sigaction act;
 	int n;
 	char error_buf[256];

 	if (argc != 2)
 			bb_show_usage();

 	fn = argv[1];
 	ttyfd = open("/dev/tty", O_RDWR);
 	if (ttyfd < 0)
 			bb_error_msg_and_die("%s: open on /dev/tty failed: %m\n", argv[0]);

 	filefd = open(fn, O_RDWR|O_CREAT|O_TRUNC, 0666);
 	if (filefd < 0)
 			bb_error_msg_and_die("%s: open on %s failed: %m\n", argv[0], fn);

 	if (tcgetattr(ttyfd, &tty) < 0)
 			bb_error_msg_and_die("%s: tcgetattr failed: %m\n", argv[0]);

 	orig_tty = tty;

 	cfmakeraw(&tty);
 	tcsetattr(ttyfd, TCSAFLUSH, &tty);

 	memset(&act, 0, sizeof(act));
 	act.sa_handler = sigalrm_handler;
 	sigaction(SIGALRM, &act, 0);

 	n = receive(error_buf, sizeof(error_buf), ttyfd, filefd);

 	close(filefd);

 	tcsetattr(ttyfd, TCSAFLUSH, &orig_tty);

 	if (n < 0)
 			bb_error_msg_and_die("\n%s: receive failed:\n  %s\n",
 							   argv[0], error_buf);

 	bb_fflush_stdout_and_exit(EXIT_SUCCESS);
 }

 /*
 Local Variables:
 c-file-style: "linux"
 c-basic-offset: 4
 tab-width: 4
 End:
 */
	/*-------------------------------------------------------------------------
	* Filename: xmodem.c
	* Version: $Id: rx.c,v 1.2 2004/03/15 08:28:46 andersen Exp $
	* Copyright: Copyright (C) 2001, Hewlett-Packard Company
	* Author: Christopher Hoover <ch@hpl.hp.com>
	* Description: xmodem functionality for uploading of kernels
	* and the like
	* Created at: Thu Dec 20 01:58:08 PST 2001
	-----------------------------------------------------------------------/
	/*
	* xmodem.c: xmodem functionality for uploading of kernels and
	* the like
	*
	* Copyright (C) 2001 Hewlett-Packard Laboratories
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*
	*
	* This was originally written for blob and then adapted for busybox.
	*
	*/

	#include <stdlib.h>
	#include <stdarg.h>
	#include <stdio.h>
	#include <unistd.h>
	#include <errno.h>
	#include <termios.h>
	#include <signal.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <fcntl.h>
	#include <string.h>
	#include "busybox.h"


	#define SOH 0x01
	#define STX 0x02
	#define EOT 0x04
	#define ACK 0x06
	#define NAK 0x15
	#define CAN 0x18
	#define BS 0x08

	/*

	Cf:

	http://www.textfiles.com/apple/xmodem
	http://www.phys.washington.edu/~belonis/xmodem/docxmodem.txt
	http://www.phys.washington.edu/~belonis/xmodem/docymodem.txt
	http://www.phys.washington.edu/~belonis/xmodem/modmprot.col

	*/

	#define TIMEOUT 1
	#define TIMEOUT_LONG 10
	#define MAXERRORS 10

	static inline void write_byte(int fd, char cc) {
	write(fd, &cc, 1);
	}

	static inline void write_flush(int fd) {
	tcdrain(fd);
	}

	static inline void read_flush(int fd) {
	tcflush(fd, TCIFLUSH);
	}

	static int read_byte(int fd, unsigned int timeout) {
	char buf[1];
	int n;

	alarm(timeout);

	n = read(fd, &buf, 1);

	alarm(0);

	if (n == 1)
	return buf[0] & 0xff;
	else
	return -1;
	}

	static int receive(char *error_buf, size_t error_buf_size,
	int ttyfd, int filefd)
	{
	char blockBuf[1024];
	unsigned int errors = 0;
	unsigned int wantBlockNo = 1;
	unsigned int length = 0;
	int docrc = 1;
	char nak = 'C';
	unsigned int timeout = TIMEOUT_LONG;

	#define note_error(fmt,args...) \
	snprintf(error_buf, error_buf_size, fmt,##args)

	read_flush(ttyfd);

	/* Ask for CRC; if we get errors, we will go with checksum */
	write_byte(ttyfd, nak);
	write_flush(ttyfd);

	for (;;) {
	int blockBegin;
	int blockNo, blockNoOnesCompl;
	int blockLength;
	int cksum = 0;
	int crcHi = 0;
	int crcLo = 0;

	blockBegin = read_byte(ttyfd, timeout);
	if (blockBegin < 0)
	goto timeout;

	timeout = TIMEOUT;
	nak = NAK;

	switch (blockBegin) {
	case SOH:
	case STX:
	break;

	case EOT:
	write_byte(ttyfd, ACK);
	write_flush(ttyfd);
	goto done;

	default:
	goto error;
	}

	/* block no */
	blockNo = read_byte(ttyfd, TIMEOUT);
	if (blockNo < 0)
	goto timeout;

	/* block no one's compliment */
	blockNoOnesCompl = read_byte(ttyfd, TIMEOUT);
	if (blockNoOnesCompl < 0)
	goto timeout;

	if (blockNo != (255 - blockNoOnesCompl)) {
	note_error("bad block ones compl");
	goto error;
	}

	blockLength = (blockBegin == SOH) ? 128 : 1024;

	{
	int i;

	for (i = 0; i < blockLength; i++) {
	int cc = read_byte(ttyfd, TIMEOUT);
	if (cc < 0)
	goto timeout;
	blockBuf[i] = cc;
	}
	}

	if (docrc) {
	crcHi = read_byte(ttyfd, TIMEOUT);
	if (crcHi < 0)
	goto timeout;

	crcLo = read_byte(ttyfd, TIMEOUT);
	if (crcLo < 0)
	goto timeout;
	} else {
	cksum = read_byte(ttyfd, TIMEOUT);
	if (cksum < 0)
	goto timeout;
	}

	if (blockNo == ((wantBlockNo - 1) & 0xff)) {
	/* a repeat of the last block is ok, just ignore it. */
	/* this also ignores the initial block 0 which is */
	/* meta data. */
	goto next;
	} else if (blockNo != (wantBlockNo & 0xff)) {
	note_error("unexpected block no, 0x%08x, expecting 0x%08x", blockNo, wantBlockNo);
	goto error;
	}

	if (docrc) {
	int crc = 0;
	int i, j;
	int expectedCrcHi;
	int expectedCrcLo;

	for (i = 0; i < blockLength; i++) {
	crc = crc ^ (int) blockBuf[i] << 8;
	for (j = 0; j < 8; j++)
	if (crc & 0x8000)
	crc = crc << 1 ^ 0x1021;
	else
	crc = crc << 1;
	}

	expectedCrcHi = (crc >> 8) & 0xff;
	expectedCrcLo = crc & 0xff;

	if ((crcHi != expectedCrcHi) \|\|
	(crcLo != expectedCrcLo)) {
	note_error("crc error, expected 0x%02x 0x%02x, got 0x%02x 0x%02x", expectedCrcHi, expectedCrcLo, crcHi, crcLo);
	goto error;
	}
	} else {
	unsigned char expectedCksum = 0;
	int i;

	for (i = 0; i < blockLength; i++)
	expectedCksum += blockBuf[i];

	if (cksum != expectedCksum) {
	note_error("checksum error, expected 0x%02x, got 0x%02x", expectedCksum, cksum);
	goto error;
	}
	}

	wantBlockNo++;
	length += blockLength;

	if (bb_full_write(filefd, blockBuf, blockLength) < 0) {
	note_error("write to file failed: %m");
	goto fatal;
	}

	next:
	errors = 0;
	write_byte(ttyfd, ACK);
	write_flush(ttyfd);
	continue;

	error:
	timeout:
	errors++;
	if (errors == MAXERRORS) {
	/* Abort */
	int i;

	// if using crc, try again w/o crc
	if (nak == 'C') {
	nak = NAK;
	errors = 0;
	docrc = 0;
	goto timeout;
	}

	note_error("too many errors; giving up");

	fatal:
	for (i = 0; i < 5; i ++)
	write_byte(ttyfd, CAN);
	for (i = 0; i < 5; i ++)
	write_byte(ttyfd, BS);
	write_flush(ttyfd);
	return -1;
	}

	read_flush(ttyfd);
	write_byte(ttyfd, nak);
	write_flush(ttyfd);
	}

	done:
	return length;

	#undef note_error
	}

	static void sigalrm_handler(int signum)
	{
	}

	int rx_main(int argc, char **argv)
	{
	char *fn;
	int ttyfd, filefd;
	struct termios tty, orig_tty;
	struct sigaction act;
	int n;
	char error_buf[256];

	if (argc != 2)
	bb_show_usage();

	fn = argv[1];
	ttyfd = open("/dev/tty", O_RDWR);
	if (ttyfd < 0)
	bb_error_msg_and_die("%s: open on /dev/tty failed: %m\n", argv[0]);

	filefd = open(fn, O_RDWR\|O_CREAT\|O_TRUNC, 0666);
	if (filefd < 0)
	bb_error_msg_and_die("%s: open on %s failed: %m\n", argv[0], fn);

	if (tcgetattr(ttyfd, &tty) < 0)
	bb_error_msg_and_die("%s: tcgetattr failed: %m\n", argv[0]);

	orig_tty = tty;

	cfmakeraw(&tty);
	tcsetattr(ttyfd, TCSAFLUSH, &tty);

	memset(&act, 0, sizeof(act));
	act.sa_handler = sigalrm_handler;
	sigaction(SIGALRM, &act, 0);

	n = receive(error_buf, sizeof(error_buf), ttyfd, filefd);

	close(filefd);

	tcsetattr(ttyfd, TCSAFLUSH, &orig_tty);

	if (n < 0)
	bb_error_msg_and_die("\n%s: receive failed:\n %s\n",
	argv[0], error_buf);

	bb_fflush_stdout_and_exit(EXIT_SUCCESS);
	}

	/*
	Local Variables:
	c-file-style: "linux"
	c-basic-offset: 4
	tab-width: 4
	End:
	*/