Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 | /*
*
* AT chat library with GLib integration
*
* Copyright (C) 2008-2011 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <arpa/inet.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <glib.h>
#include "crc-ccitt.h"
#include "ringbuffer.h"
#include "gatio.h"
#include "gatutil.h"
#include "gathdlc.h"
#define BUFFER_SIZE (2 * 2048)
#define MAX_BUFFERS 64 /* Maximum number of in-flight write buffers */
#define HDLC_OVERHEAD 256 /* Rough estimate of HDLC protocol overhead */
#define HDLC_FLAG 0x7e /* Flag sequence */
#define HDLC_ESCAPE 0x7d /* Asynchronous control escape */
#define HDLC_TRANS 0x20 /* Asynchronous transparency modifier */
#define HDLC_INITFCS 0xffff /* Initial FCS value */
#define HDLC_GOODFCS 0xf0b8 /* Good final FCS value */
#define HDLC_FCS(fcs, c) crc_ccitt_byte(fcs, c)
#define GUARD_TIMEOUT 1000 /* Pause time before and after '+++' sequence */
struct _GAtHDLC {
gint ref_count;
GAtIO *io;
GQueue *write_queue; /* Write buffer queue */
unsigned char *decode_buffer;
guint decode_offset;
guint16 decode_fcs;
gboolean decode_escape;
guint32 xmit_accm[8];
guint32 recv_accm;
GAtReceiveFunc receive_func;
gpointer receive_data;
GAtDebugFunc debugf;
gpointer debug_data;
int record_fd;
gboolean in_read_handler;
gboolean destroyed;
gboolean wakeup_sent;
gboolean start_frame_marker;
gboolean no_carrier_detect;
GAtSuspendFunc suspend_func;
gpointer suspend_data;
guint suspend_source;
GTimer *timer;
guint num_plus;
};
static inline void hdlc_record(GAtHDLC *hdlc, gboolean in,
guint8 *data, guint16 length)
{
guint16 len = htons(length);
guint32 ts;
struct timeval now;
unsigned char id;
int err;
g_at_util_debug_hexdump(in, data, length,
hdlc->debugf, hdlc->debug_data);
if (hdlc->record_fd < 0)
return;
if (length == 0)
return;
gettimeofday(&now, NULL);
ts = htonl(now.tv_sec & 0xffffffff);
id = 0x07;
err = write(hdlc->record_fd, &id, 1);
if (err < 0)
return;
err = write(hdlc->record_fd, &ts, 4);
if (err < 0)
return;
id = in ? 0x02 : 0x01;
err = write(hdlc->record_fd, &id, 1);
if (err < 0)
return;
err = write(hdlc->record_fd, &len, 2);
if (err < 0)
return;
err = write(hdlc->record_fd, data, length);
if (err < 0)
return;
}
void g_at_hdlc_set_recording(GAtHDLC *hdlc, const char *filename)
{
if (hdlc == NULL)
return;
if (hdlc->record_fd > fileno(stderr)) {
close(hdlc->record_fd);
hdlc->record_fd = -1;
}
if (filename == NULL)
return;
hdlc->record_fd = open(filename, O_WRONLY | O_CREAT | O_APPEND,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
}
void g_at_hdlc_set_recv_accm(GAtHDLC *hdlc, guint32 accm)
{
if (hdlc == NULL)
return;
hdlc->recv_accm = accm;
}
guint32 g_at_hdlc_get_recv_accm(GAtHDLC *hdlc)
{
if (hdlc == NULL)
return 0;
return hdlc->recv_accm;
}
void g_at_hdlc_set_suspend_function(GAtHDLC *hdlc, GAtSuspendFunc func,
gpointer user_data)
{
if (hdlc == NULL)
return;
if (func == NULL) {
if (hdlc->timer) {
g_timer_destroy(hdlc->timer);
hdlc->timer = NULL;
}
if (hdlc->suspend_source > 0) {
g_source_remove(hdlc->suspend_source);
hdlc->suspend_source = 0;
}
} else
hdlc->timer = g_timer_new();
hdlc->suspend_func = func;
hdlc->suspend_data = user_data;
}
static gboolean hdlc_suspend(gpointer user_data)
{
GAtHDLC *hdlc = user_data;
g_at_io_drain_ring_buffer(hdlc->io, 3);
g_at_io_set_write_handler(hdlc->io, NULL, NULL);
g_at_io_set_read_handler(hdlc->io, NULL, NULL);
if (hdlc->suspend_func)
hdlc->suspend_func(hdlc->suspend_data);
hdlc->suspend_source = 0;
return FALSE;
}
static gboolean check_escape(GAtHDLC *hdlc, struct ring_buffer *rbuf)
{
unsigned int len = ring_buffer_len(rbuf);
unsigned int wrap = ring_buffer_len_no_wrap(rbuf);
unsigned char *buf = ring_buffer_read_ptr(rbuf, 0);
unsigned int pos = 0;
unsigned int elapsed = g_timer_elapsed(hdlc->timer, NULL) * 1000;
unsigned int num_plus = 0;
gboolean guard_timeout = FALSE;
if (elapsed >= GUARD_TIMEOUT)
guard_timeout = TRUE;
while (pos < len && pos < 3) {
if (*buf != '+')
break;
num_plus++;
buf++;
pos++;
if (pos == wrap)
buf = ring_buffer_read_ptr(rbuf, pos);
}
if (num_plus != len)
return FALSE;
/* We got some escape chars, but no guard timeout first */
if (guard_timeout == FALSE && hdlc->num_plus == 0)
return FALSE;
if (num_plus != 3) {
hdlc->num_plus = num_plus;
return TRUE;
}
hdlc->num_plus = 0;
hdlc->suspend_source = g_timeout_add(GUARD_TIMEOUT, hdlc_suspend, hdlc);
return TRUE;
}
static void new_bytes(struct ring_buffer *rbuf, gpointer user_data)
{
GAtHDLC *hdlc = user_data;
unsigned int len = ring_buffer_len(rbuf);
unsigned int wrap = ring_buffer_len_no_wrap(rbuf);
unsigned char *buf = ring_buffer_read_ptr(rbuf, 0);
unsigned int pos = 0;
/*
* We delete the the paused_timeout_cb or hdlc_suspend as soons as
* we read a data.
*/
if (hdlc->suspend_source > 0) {
g_source_remove(hdlc->suspend_source);
hdlc->suspend_source = 0;
g_timer_start(hdlc->timer);
} else if (hdlc->timer) {
gboolean escaping = check_escape(hdlc, rbuf);
g_timer_start(hdlc->timer);
if (escaping)
return;
}
hdlc_record(hdlc, TRUE, buf, wrap);
hdlc->in_read_handler = TRUE;
while (pos < len) {
/*
* We try to detect NO CARRIER conditions here. We
* (ab) use the fact that a HDLC_FLAG must be followed
* by the Address or Protocol fields, depending on whether
* ACFC is enabled.
*/
if (hdlc->no_carrier_detect &&
hdlc->decode_offset == 0 && *buf == '\r')
break;
if (hdlc->decode_escape == TRUE) {
unsigned char val = *buf ^ HDLC_TRANS;
hdlc->decode_buffer[hdlc->decode_offset++] = val;
hdlc->decode_fcs = HDLC_FCS(hdlc->decode_fcs, val);
hdlc->decode_escape = FALSE;
} else if (*buf == HDLC_ESCAPE) {
hdlc->decode_escape = TRUE;
} else if (*buf == HDLC_FLAG) {
if (hdlc->receive_func && hdlc->decode_offset > 2 &&
hdlc->decode_fcs == HDLC_GOODFCS) {
hdlc->receive_func(hdlc->decode_buffer,
hdlc->decode_offset - 2,
hdlc->receive_data);
if (hdlc->destroyed)
goto out;
}
hdlc->decode_fcs = HDLC_INITFCS;
hdlc->decode_offset = 0;
} else if (*buf >= 0x20 ||
(hdlc->recv_accm & (1 << *buf)) == 0) {
hdlc->decode_buffer[hdlc->decode_offset++] = *buf;
hdlc->decode_fcs = HDLC_FCS(hdlc->decode_fcs, *buf);
}
buf++;
pos++;
if (pos == wrap) {
buf = ring_buffer_read_ptr(rbuf, pos);
hdlc_record(hdlc, TRUE, buf, len - wrap);
}
}
out:
ring_buffer_drain(rbuf, pos);
hdlc->in_read_handler = FALSE;
if (hdlc->destroyed)
g_free(hdlc);
}
GAtHDLC *g_at_hdlc_new_from_io(GAtIO *io)
{
GAtHDLC *hdlc;
struct ring_buffer* write_buffer;
if (io == NULL)
return NULL;
hdlc = g_try_new0(GAtHDLC, 1);
if (hdlc == NULL)
return NULL;
hdlc->ref_count = 1;
hdlc->decode_fcs = HDLC_INITFCS;
hdlc->decode_offset = 0;
hdlc->decode_escape = FALSE;
hdlc->xmit_accm[0] = ~0U;
hdlc->xmit_accm[3] = 0x60000000; /* 0x7d, 0x7e */
hdlc->recv_accm = ~0U;
write_buffer = ring_buffer_new(BUFFER_SIZE);
if (!write_buffer)
goto error;
hdlc->write_queue = g_queue_new();
if (!hdlc->write_queue)
goto error;
g_queue_push_tail(hdlc->write_queue, write_buffer);
hdlc->decode_buffer = g_try_malloc(BUFFER_SIZE);
if (!hdlc->decode_buffer)
goto error;
hdlc->record_fd = -1;
hdlc->io = g_at_io_ref(io);
g_at_io_set_read_handler(hdlc->io, new_bytes, hdlc);
return hdlc;
error:
if (hdlc->write_queue)
g_queue_free(hdlc->write_queue);
if (write_buffer)
ring_buffer_free(write_buffer);
g_free(hdlc->decode_buffer);
g_free(hdlc);
return NULL;
}
GAtHDLC *g_at_hdlc_new(GIOChannel *channel)
{
GAtIO *io;
GAtHDLC *hdlc;
io = g_at_io_new(channel);
if (io == NULL)
return NULL;
hdlc = g_at_hdlc_new_from_io(io);
g_at_io_unref(io);
return hdlc;
}
GAtHDLC *g_at_hdlc_ref(GAtHDLC *hdlc)
{
if (hdlc == NULL)
return NULL;
g_atomic_int_inc(&hdlc->ref_count);
return hdlc;
}
void g_at_hdlc_unref(GAtHDLC *hdlc)
{
struct ring_buffer *write_buffer;
if (hdlc == NULL)
return;
if (g_atomic_int_dec_and_test(&hdlc->ref_count) == FALSE)
return;
if (hdlc->record_fd > fileno(stderr)) {
close(hdlc->record_fd);
hdlc->record_fd = -1;
}
g_at_io_set_write_handler(hdlc->io, NULL, NULL);
g_at_io_set_read_handler(hdlc->io, NULL, NULL);
if (hdlc->suspend_source > 0)
g_source_remove(hdlc->suspend_source);
g_at_io_unref(hdlc->io);
hdlc->io = NULL;
while ((write_buffer = g_queue_pop_head(hdlc->write_queue)))
ring_buffer_free(write_buffer);
g_queue_free(hdlc->write_queue);
g_free(hdlc->decode_buffer);
g_timer_destroy(hdlc->timer);
if (hdlc->in_read_handler)
hdlc->destroyed = TRUE;
else
g_free(hdlc);
}
void g_at_hdlc_set_debug(GAtHDLC *hdlc, GAtDebugFunc func, gpointer user_data)
{
if (hdlc == NULL)
return;
hdlc->debugf = func;
hdlc->debug_data = user_data;
}
void g_at_hdlc_set_receive(GAtHDLC *hdlc, GAtReceiveFunc func,
gpointer user_data)
{
if (hdlc == NULL)
return;
hdlc->receive_func = func;
hdlc->receive_data = user_data;
}
static gboolean can_write_data(gpointer data)
{
GAtHDLC *hdlc = data;
unsigned int len;
unsigned char *buf;
gsize bytes_written;
struct ring_buffer* write_buffer;
/* Write data out from the head of the queue */
write_buffer = g_queue_peek_head(hdlc->write_queue);
len = ring_buffer_len_no_wrap(write_buffer);
buf = ring_buffer_read_ptr(write_buffer, 0);
bytes_written = g_at_io_write(hdlc->io, (gchar *) buf, len);
hdlc_record(hdlc, FALSE, buf, bytes_written);
ring_buffer_drain(write_buffer, bytes_written);
if (ring_buffer_len(write_buffer) > 0)
return TRUE;
/* All data in current buffer is written, free it
* unless it's the last buffer in the queue.
*/
if ((ring_buffer_len(write_buffer) == 0) &&
(g_queue_get_length(hdlc->write_queue) > 1)) {
write_buffer = g_queue_pop_head(hdlc->write_queue);
ring_buffer_free(write_buffer);
write_buffer = g_queue_peek_head(hdlc->write_queue);
}
if (ring_buffer_len(write_buffer) > 0)
return TRUE;
return FALSE;
}
void g_at_hdlc_set_xmit_accm(GAtHDLC *hdlc, guint32 accm)
{
if (hdlc == NULL)
return;
hdlc->xmit_accm[0] = accm;
}
guint32 g_at_hdlc_get_xmit_accm(GAtHDLC *hdlc)
{
if (hdlc == NULL)
return 0;
return hdlc->xmit_accm[0];
}
GAtIO *g_at_hdlc_get_io(GAtHDLC *hdlc)
{
if (hdlc == NULL)
return NULL;
return hdlc->io;
}
#define NEED_ESCAPE(xmit_accm, c) xmit_accm[c >> 5] & (1 << (c & 0x1f))
gboolean g_at_hdlc_send(GAtHDLC *hdlc, const unsigned char *data, gsize size)
{
struct ring_buffer* write_buffer = g_queue_peek_tail(hdlc->write_queue);
unsigned int avail = ring_buffer_avail(write_buffer);
unsigned int wrap = ring_buffer_avail_no_wrap(write_buffer);
unsigned char *buf;
unsigned char tail[2];
unsigned int i = 0;
guint16 fcs = HDLC_INITFCS;
gboolean escape = FALSE;
gsize pos = 0;
if (avail < size + HDLC_OVERHEAD) {
if (g_queue_get_length(hdlc->write_queue) > MAX_BUFFERS)
return FALSE; /* Too many pending buffers */
write_buffer = ring_buffer_new(BUFFER_SIZE);
if (write_buffer == NULL)
return FALSE;
g_queue_push_tail(hdlc->write_queue, write_buffer);
avail = ring_buffer_avail(write_buffer);
wrap = ring_buffer_avail_no_wrap(write_buffer);
}
i = 0;
buf = ring_buffer_write_ptr(write_buffer, 0);
if (hdlc->start_frame_marker == TRUE) {
/* Protocol requires 0x7e as start marker */
if (pos + 1 > avail)
return FALSE;
*buf++ = HDLC_FLAG;
pos++;
if (pos == wrap)
buf = ring_buffer_write_ptr(write_buffer, pos);
} else if (hdlc->wakeup_sent == FALSE) {
/* Write an initial 0x7e as wakeup character */
*buf++ = HDLC_FLAG;
pos++;
hdlc->wakeup_sent = TRUE;
}
while (pos < avail && i < size) {
if (escape == TRUE) {
fcs = HDLC_FCS(fcs, data[i]);
*buf = data[i++] ^ HDLC_TRANS;
escape = FALSE;
} else if (NEED_ESCAPE(hdlc->xmit_accm, data[i])) {
*buf = HDLC_ESCAPE;
escape = TRUE;
} else {
fcs = HDLC_FCS(fcs, data[i]);
*buf = data[i++];
}
buf++;
pos++;
if (pos == wrap)
buf = ring_buffer_write_ptr(write_buffer, pos);
}
if (i < size)
return FALSE;
fcs ^= HDLC_INITFCS;
tail[0] = fcs & 0xff;
tail[1] = fcs >> 8;
i = 0;
while (pos < avail && i < sizeof(tail)) {
if (escape == TRUE) {
*buf = tail[i++] ^ HDLC_TRANS;
escape = FALSE;
} else if (NEED_ESCAPE(hdlc->xmit_accm, tail[i])) {
*buf = HDLC_ESCAPE;
escape = TRUE;
} else {
*buf = tail[i++];
}
buf++;
pos++;
if (pos == wrap)
buf = ring_buffer_write_ptr(write_buffer, pos);
}
if (i < sizeof(tail))
return FALSE;
if (pos + 1 > avail)
return FALSE;
/* Add 0x7e as end marker */
*buf = HDLC_FLAG;
pos++;
ring_buffer_write_advance(write_buffer, pos);
g_at_io_set_write_handler(hdlc->io, can_write_data, hdlc);
return TRUE;
}
void g_at_hdlc_set_start_frame_marker(GAtHDLC *hdlc, gboolean marker)
{
if (hdlc == NULL)
return;
hdlc->start_frame_marker = marker;
}
void g_at_hdlc_set_no_carrier_detect(GAtHDLC *hdlc, gboolean detect)
{
if (hdlc == NULL)
return;
hdlc->no_carrier_detect = detect;
}
void g_at_hdlc_suspend(GAtHDLC *hdlc)
{
if (hdlc == NULL)
return;
g_at_io_set_write_handler(hdlc->io, NULL, NULL);
g_at_io_set_read_handler(hdlc->io, NULL, NULL);
}
void g_at_hdlc_resume(GAtHDLC *hdlc)
{
if (hdlc == NULL)
return;
g_at_io_set_read_handler(hdlc->io, new_bytes, hdlc);
if (g_queue_get_length(hdlc->write_queue) > 0)
g_at_io_set_write_handler(hdlc->io, can_write_data, hdlc);
}
|