gdb/serial.c

   1 /* Generic serial interface routines
   2
   3    Copyright (C) 1992-2020 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include <ctype.h>
  22 #include "serial.h"
  23 #include "gdbcmd.h"
  24 #include "cli/cli-utils.h"
  25
  26 /* Is serial being debugged?  */
  27
  28 static unsigned int global_serial_debug_p;
  29
  30 /* Serial I/O handlers.  */
  31
  32 static std::vector<const struct serial_ops *> serial_ops_list;
  33
  34 /* Pointer to list of scb's.  */
  35
  36 static struct serial *scb_base;
  37
  38 /* Non-NULL gives filename which contains a recording of the remote session,
  39    suitable for playback by gdbserver.  */
  40
  41 static char *serial_logfile = NULL;
  42 static struct ui_file *serial_logfp = NULL;
  43
  44 static const struct serial_ops *serial_interface_lookup (const char *);
  45 static void serial_logchar (struct ui_file *stream,
  46                             int ch_type, int ch, int timeout);
  47 static const char logbase_hex[] = "hex";
  48 static const char logbase_octal[] = "octal";
  49 static const char logbase_ascii[] = "ascii";
  50 static const char *const logbase_enums[] =
  51 {logbase_hex, logbase_octal, logbase_ascii, NULL};
  52 static const char *serial_logbase = logbase_ascii;
  53 \f
  54
  55 static int serial_current_type = 0;
  56
  57 /* Log char CH of type CHTYPE, with TIMEOUT.  */
  58
  59 /* Define bogus char to represent a BREAK.  Should be careful to choose a value
  60    that can't be confused with a normal char, or an error code.  */
  61 #define SERIAL_BREAK 1235
  62
  63 static void
  64 serial_logchar (struct ui_file *stream, int ch_type, int ch, int timeout)
  65 {
  66   if (ch_type != serial_current_type)
  67     {
  68       fprintf_unfiltered (stream, "\n%c ", ch_type);
  69       serial_current_type = ch_type;
  70     }
  71
  72   if (serial_logbase != logbase_ascii)
  73     fputc_unfiltered (' ', stream);
  74
  75   switch (ch)
  76     {
  77     case SERIAL_TIMEOUT:
  78       fprintf_unfiltered (stream, "<Timeout: %d seconds>", timeout);
  79       return;
  80     case SERIAL_ERROR:
  81       fprintf_unfiltered (stream, "<Error: %s>", safe_strerror (errno));
  82       return;
  83     case SERIAL_EOF:
  84       fputs_unfiltered ("<Eof>", stream);
  85       return;
  86     case SERIAL_BREAK:
  87       fputs_unfiltered ("<Break>", stream);
  88       return;
  89     default:
  90       if (serial_logbase == logbase_hex)
  91         fprintf_unfiltered (stream, "%02x", ch & 0xff);
  92       else if (serial_logbase == logbase_octal)
  93         fprintf_unfiltered (stream, "%03o", ch & 0xff);
  94       else
  95         switch (ch)
  96           {
  97           case '\\':
  98             fputs_unfiltered ("\\\\", stream);
  99             break;
 100           case '\b':
 101             fputs_unfiltered ("\\b", stream);
 102             break;
 103           case '\f':
 104             fputs_unfiltered ("\\f", stream);
 105             break;
 106           case '\n':
 107             fputs_unfiltered ("\\n", stream);
 108             break;
 109           case '\r':
 110             fputs_unfiltered ("\\r", stream);
 111             break;
 112           case '\t':
 113             fputs_unfiltered ("\\t", stream);
 114             break;
 115           case '\v':
 116             fputs_unfiltered ("\\v", stream);
 117             break;
 118           default:
 119             fprintf_unfiltered (stream,
 120                                 isprint (ch) ? "%c" : "\\x%02x", ch & 0xFF);
 121             break;
 122           }
 123     }
 124 }
 125
 126 void
 127 serial_log_command (struct target_ops *self, const char *cmd)
 128 {
 129   if (!serial_logfp)
 130     return;
 131
 132   serial_current_type = 'c';
 133
 134   fputs_unfiltered ("\nc ", serial_logfp);
 135   fputs_unfiltered (cmd, serial_logfp);
 136
 137   /* Make sure that the log file is as up-to-date as possible,
 138      in case we are getting ready to dump core or something.  */
 139   gdb_flush (serial_logfp);
 140 }
 141
 142 \f
 143 static const struct serial_ops *
 144 serial_interface_lookup (const char *name)
 145 {
 146   for (const serial_ops *ops : serial_ops_list)
 147     if (strcmp (name, ops->name) == 0)
 148       return ops;
 149
 150   return NULL;
 151 }
 152
 153 void
 154 serial_add_interface (const struct serial_ops *optable)
 155 {
 156   serial_ops_list.push_back (optable);
 157 }
 158
 159 /* Return the open serial device for FD, if found, or NULL if FD is
 160    not already opened.  */
 161
 162 struct serial *
 163 serial_for_fd (int fd)
 164 {
 165   struct serial *scb;
 166
 167   for (scb = scb_base; scb; scb = scb->next)
 168     if (scb->fd == fd)
 169       return scb;
 170
 171   return NULL;
 172 }
 173
 174 /* Create a new serial for OPS.  */
 175
 176 static struct serial *
 177 new_serial (const struct serial_ops *ops)
 178 {
 179   struct serial *scb;
 180
 181   scb = XCNEW (struct serial);
 182
 183   scb->ops = ops;
 184
 185   scb->bufp = scb->buf;
 186   scb->error_fd = -1;
 187   scb->refcnt = 1;
 188
 189   return scb;
 190 }
 191
 192 static struct serial *serial_open_ops_1 (const struct serial_ops *ops,
 193                                          const char *open_name);
 194
 195 /* Open up a device or a network socket, depending upon the syntax of NAME.  */
 196
 197 struct serial *
 198 serial_open (const char *name)
 199 {
 200   const struct serial_ops *ops;
 201   const char *open_name = name;
 202
 203   if (startswith (name, "|"))
 204     {
 205       ops = serial_interface_lookup ("pipe");
 206       /* Discard ``|'' and any space before the command itself.  */
 207       ++open_name;
 208       open_name = skip_spaces (open_name);
 209     }
 210   /* Check for a colon, suggesting an IP address/port pair.
 211      Do this *after* checking for all the interesting prefixes.  We
 212      don't want to constrain the syntax of what can follow them.  */
 213   else if (strchr (name, ':'))
 214     ops = serial_interface_lookup ("tcp");
 215   else
 216     {
 217 #ifndef USE_WIN32API
 218       /* Check to see if name is a socket.  If it is, then treat it
 219          as such.  Otherwise assume that it's a character device.  */
 220       struct stat sb;
 221       if (stat (name, &sb) == 0 && (sb.st_mode & S_IFMT) == S_IFSOCK)
 222         ops = serial_interface_lookup ("local");
 223       else
 224 #endif
 225         ops = serial_interface_lookup ("hardwire");
 226     }
 227
 228   if (!ops)
 229     return NULL;
 230
 231   return serial_open_ops_1 (ops, open_name);
 232 }
 233
 234 /* Open up a serial for OPS, passing OPEN_NAME to the open method.  */
 235
 236 static struct serial *
 237 serial_open_ops_1 (const struct serial_ops *ops, const char *open_name)
 238 {
 239   struct serial *scb;
 240
 241   scb = new_serial (ops);
 242
 243   /* `...->open (...)' would get expanded by the open(2) syscall macro.  */
 244   if ((*scb->ops->open) (scb, open_name))
 245     {
 246       xfree (scb);
 247       return NULL;
 248     }
 249
 250   scb->name = open_name != NULL ? xstrdup (open_name) : NULL;
 251   scb->next = scb_base;
 252   scb_base = scb;
 253
 254   if (serial_logfile != NULL)
 255     {
 256       stdio_file_up file (new stdio_file ());
 257
 258       if (!file->open (serial_logfile, "w"))
 259         perror_with_name (serial_logfile);
 260
 261       serial_logfp = file.release ();
 262     }
 263
 264   return scb;
 265 }
 266
 267 /* See serial.h.  */
 268
 269 struct serial *
 270 serial_open_ops (const struct serial_ops *ops)
 271 {
 272   return serial_open_ops_1 (ops, NULL);
 273 }
 274
 275 /* Open a new serial stream using a file handle, using serial
 276    interface ops OPS.  */
 277
 278 static struct serial *
 279 serial_fdopen_ops (const int fd, const struct serial_ops *ops)
 280 {
 281   struct serial *scb;
 282
 283   if (!ops)
 284     {
 285       ops = serial_interface_lookup ("terminal");
 286       if (!ops)
 287         ops = serial_interface_lookup ("hardwire");
 288     }
 289
 290   if (!ops)
 291     return NULL;
 292
 293   scb = new_serial (ops);
 294
 295   scb->name = NULL;
 296   scb->next = scb_base;
 297   scb_base = scb;
 298
 299   if ((ops->fdopen) != NULL)
 300     (*ops->fdopen) (scb, fd);
 301   else
 302     scb->fd = fd;
 303
 304   return scb;
 305 }
 306
 307 struct serial *
 308 serial_fdopen (const int fd)
 309 {
 310   return serial_fdopen_ops (fd, NULL);
 311 }
 312
 313 static void
 314 do_serial_close (struct serial *scb, int really_close)
 315 {
 316   struct serial *tmp_scb;
 317
 318   if (serial_logfp)
 319     {
 320       fputs_unfiltered ("\nEnd of log\n", serial_logfp);
 321       serial_current_type = 0;
 322
 323       /* XXX - What if serial_logfp == gdb_stdout or gdb_stderr?  */
 324       delete serial_logfp;
 325       serial_logfp = NULL;
 326     }
 327
 328   /* ensure that the FD has been taken out of async mode.  */
 329   if (scb->async_handler != NULL)
 330     serial_async (scb, NULL, NULL);
 331
 332   if (really_close)
 333     scb->ops->close (scb);
 334
 335   xfree (scb->name);
 336
 337   /* For serial_is_open.  */
 338   scb->bufp = NULL;
 339
 340   if (scb_base == scb)
 341     scb_base = scb_base->next;
 342   else
 343     for (tmp_scb = scb_base; tmp_scb; tmp_scb = tmp_scb->next)
 344       {
 345         if (tmp_scb->next != scb)
 346           continue;
 347
 348         tmp_scb->next = tmp_scb->next->next;
 349         break;
 350       }
 351
 352   serial_unref (scb);
 353 }
 354
 355 void
 356 serial_close (struct serial *scb)
 357 {
 358   do_serial_close (scb, 1);
 359 }
 360
 361 void
 362 serial_un_fdopen (struct serial *scb)
 363 {
 364   do_serial_close (scb, 0);
 365 }
 366
 367 int
 368 serial_is_open (struct serial *scb)
 369 {
 370   return scb->bufp != NULL;
 371 }
 372
 373 void
 374 serial_ref (struct serial *scb)
 375 {
 376   scb->refcnt++;
 377 }
 378
 379 void
 380 serial_unref (struct serial *scb)
 381 {
 382   --scb->refcnt;
 383   if (scb->refcnt == 0)
 384     xfree (scb);
 385 }
 386
 387 int
 388 serial_readchar (struct serial *scb, int timeout)
 389 {
 390   int ch;
 391
 392   /* FIXME: cagney/1999-10-11: Don't enable this check until the ASYNC
 393      code is finished.  */
 394   if (0 && serial_is_async_p (scb) && timeout < 0)
 395     internal_error (__FILE__, __LINE__,
 396                     _("serial_readchar: blocking read in async mode"));
 397
 398   ch = scb->ops->readchar (scb, timeout);
 399   if (serial_logfp != NULL)
 400     {
 401       serial_logchar (serial_logfp, 'r', ch, timeout);
 402
 403       /* Make sure that the log file is as up-to-date as possible,
 404          in case we are getting ready to dump core or something.  */
 405       gdb_flush (serial_logfp);
 406     }
 407   if (serial_debug_p (scb))
 408     {
 409       fprintf_unfiltered (gdb_stdlog, "[");
 410       serial_logchar (gdb_stdlog, 'r', ch, timeout);
 411       fprintf_unfiltered (gdb_stdlog, "]");
 412       gdb_flush (gdb_stdlog);
 413     }
 414
 415   return (ch);
 416 }
 417
 418 int
 419 serial_write (struct serial *scb, const void *buf, size_t count)
 420 {
 421   if (serial_logfp != NULL)
 422     {
 423       const char *str = (const char *) buf;
 424       size_t c;
 425
 426       for (c = 0; c < count; c++)
 427         serial_logchar (serial_logfp, 'w', str[c] & 0xff, 0);
 428
 429       /* Make sure that the log file is as up-to-date as possible,
 430          in case we are getting ready to dump core or something.  */
 431       gdb_flush (serial_logfp);
 432     }
 433   if (serial_debug_p (scb))
 434     {
 435       const char *str = (const char *) buf;
 436       size_t c;
 437
 438       for (c = 0; c < count; c++)
 439         {
 440           fprintf_unfiltered (gdb_stdlog, "[");
 441           serial_logchar (gdb_stdlog, 'w', str[c] & 0xff, 0);
 442           fprintf_unfiltered (gdb_stdlog, "]");
 443         }
 444       gdb_flush (gdb_stdlog);
 445     }
 446
 447   return (scb->ops->write (scb, buf, count));
 448 }
 449
 450 void
 451 serial_printf (struct serial *desc, const char *format, ...)
 452 {
 453   va_list args;
 454   va_start (args, format);
 455
 456   std::string buf = string_vprintf (format, args);
 457   serial_write (desc, buf.c_str (), buf.length ());
 458
 459   va_end (args);
 460 }
 461
 462 int
 463 serial_drain_output (struct serial *scb)
 464 {
 465   return scb->ops->drain_output (scb);
 466 }
 467
 468 int
 469 serial_flush_output (struct serial *scb)
 470 {
 471   return scb->ops->flush_output (scb);
 472 }
 473
 474 int
 475 serial_flush_input (struct serial *scb)
 476 {
 477   return scb->ops->flush_input (scb);
 478 }
 479
 480 int
 481 serial_send_break (struct serial *scb)
 482 {
 483   if (serial_logfp != NULL)
 484     serial_logchar (serial_logfp, 'w', SERIAL_BREAK, 0);
 485
 486   return (scb->ops->send_break (scb));
 487 }
 488
 489 void
 490 serial_raw (struct serial *scb)
 491 {
 492   scb->ops->go_raw (scb);
 493 }
 494
 495 serial_ttystate
 496 serial_get_tty_state (struct serial *scb)
 497 {
 498   return scb->ops->get_tty_state (scb);
 499 }
 500
 501 serial_ttystate
 502 serial_copy_tty_state (struct serial *scb, serial_ttystate ttystate)
 503 {
 504   return scb->ops->copy_tty_state (scb, ttystate);
 505 }
 506
 507 int
 508 serial_set_tty_state (struct serial *scb, serial_ttystate ttystate)
 509 {
 510   return scb->ops->set_tty_state (scb, ttystate);
 511 }
 512
 513 void
 514 serial_print_tty_state (struct serial *scb,
 515                         serial_ttystate ttystate,
 516                         struct ui_file *stream)
 517 {
 518   scb->ops->print_tty_state (scb, ttystate, stream);
 519 }
 520
 521 int
 522 serial_setbaudrate (struct serial *scb, int rate)
 523 {
 524   return scb->ops->setbaudrate (scb, rate);
 525 }
 526
 527 int
 528 serial_setstopbits (struct serial *scb, int num)
 529 {
 530   return scb->ops->setstopbits (scb, num);
 531 }
 532
 533 /* See serial.h.  */
 534
 535 int
 536 serial_setparity (struct serial *scb, int parity)
 537 {
 538   return scb->ops->setparity (scb, parity);
 539 }
 540
 541 int
 542 serial_can_async_p (struct serial *scb)
 543 {
 544   return (scb->ops->async != NULL);
 545 }
 546
 547 int
 548 serial_is_async_p (struct serial *scb)
 549 {
 550   return (scb->ops->async != NULL) && (scb->async_handler != NULL);
 551 }
 552
 553 void
 554 serial_async (struct serial *scb,
 555               serial_event_ftype *handler,
 556               void *context)
 557 {
 558   int changed = ((scb->async_handler == NULL) != (handler == NULL));
 559
 560   scb->async_handler = handler;
 561   scb->async_context = context;
 562   /* Only change mode if there is a need.  */
 563   if (changed)
 564     scb->ops->async (scb, handler != NULL);
 565 }
 566
 567 void
 568 serial_debug (struct serial *scb, int debug_p)
 569 {
 570   scb->debug_p = debug_p;
 571 }
 572
 573 int
 574 serial_debug_p (struct serial *scb)
 575 {
 576   return scb->debug_p || global_serial_debug_p;
 577 }
 578
 579 #ifdef USE_WIN32API
 580 void
 581 serial_wait_handle (struct serial *scb, HANDLE *read, HANDLE *except)
 582 {
 583   if (scb->ops->wait_handle)
 584     scb->ops->wait_handle (scb, read, except);
 585   else
 586     {
 587       *read = (HANDLE) _get_osfhandle (scb->fd);
 588       *except = NULL;
 589     }
 590 }
 591
 592 void
 593 serial_done_wait_handle (struct serial *scb)
 594 {
 595   if (scb->ops->done_wait_handle)
 596     scb->ops->done_wait_handle (scb);
 597 }
 598 #endif
 599
 600 int
 601 serial_pipe (struct serial *scbs[2])
 602 {
 603   const struct serial_ops *ops;
 604   int fildes[2];
 605
 606   ops = serial_interface_lookup ("pipe");
 607   if (!ops)
 608     {
 609       errno = ENOSYS;
 610       return -1;
 611     }
 612
 613   if (gdb_pipe (fildes) == -1)
 614     return -1;
 615
 616   scbs[0] = serial_fdopen_ops (fildes[0], ops);
 617   scbs[1] = serial_fdopen_ops (fildes[1], ops);
 618   return 0;
 619 }
 620
 621 /* Serial set/show framework.  */
 622
 623 static struct cmd_list_element *serial_set_cmdlist;
 624 static struct cmd_list_element *serial_show_cmdlist;
 625
 626 /* Baud rate specified for talking to serial target systems.  Default
 627    is left as -1, so targets can choose their own defaults.  */
 628 /* FIXME: This means that "show serial baud" and gr_files_info can
 629    print -1 or (unsigned int)-1.  This is a Bad User Interface.  */
 630
 631 int baud_rate = -1;
 632
 633 static void
 634 serial_baud_show_cmd (struct ui_file *file, int from_tty,
 635                       struct cmd_list_element *c, const char *value)
 636 {
 637   fprintf_filtered (file, _("Baud rate for remote serial I/O is %s.\n"),
 638                     value);
 639 }
 640
 641 /* Parity for serial port.  */
 642
 643 int serial_parity = GDBPARITY_NONE;
 644
 645 static const char parity_none[] = "none";
 646 static const char parity_odd[] = "odd";
 647 static const char parity_even[] = "even";
 648 static const char *const parity_enums[] =
 649   {parity_none, parity_odd, parity_even,  NULL};
 650 static const char *parity = parity_none;
 651
 652 /* Set serial_parity value.  */
 653
 654 static void
 655 set_parity (const char *ignore_args, int from_tty, struct cmd_list_element *c)
 656 {
 657   if (parity == parity_odd)
 658     serial_parity = GDBPARITY_ODD;
 659   else if (parity == parity_even)
 660     serial_parity = GDBPARITY_EVEN;
 661   else
 662     serial_parity = GDBPARITY_NONE;
 663 }
 664
 665 void _initialize_serial ();
 666 void
 667 _initialize_serial ()
 668 {
 669 #if 0
 670   add_com ("connect", class_obscure, connect_command, _("\
 671 Connect the terminal directly up to the command monitor.\n\
 672 Use <CR>~. or <CR>~^D to break out."));
 673 #endif /* 0 */
 674
 675   add_basic_prefix_cmd ("serial", class_maintenance, _("\
 676 Set default serial/parallel port configuration."),
 677                         &serial_set_cmdlist, "set serial ",
 678                         0/*allow-unknown*/,
 679                         &setlist);
 680
 681   add_show_prefix_cmd ("serial", class_maintenance, _("\
 682 Show default serial/parallel port configuration."),
 683                        &serial_show_cmdlist, "show serial ",
 684                        0/*allow-unknown*/,
 685                        &showlist);
 686
 687   /* If target is open when baud changes, it doesn't take effect until
 688      the next open (I think, not sure).  */
 689   add_setshow_zinteger_cmd ("baud", no_class, &baud_rate, _("\
 690 Set baud rate for remote serial I/O."), _("\
 691 Show baud rate for remote serial I/O."), _("\
 692 This value is used to set the speed of the serial port when debugging\n\
 693 using remote targets."),
 694                             NULL,
 695                             serial_baud_show_cmd,
 696                             &serial_set_cmdlist, &serial_show_cmdlist);
 697
 698   add_setshow_enum_cmd ("parity", no_class, parity_enums,
 699                         &parity, _("\
 700 Set parity for remote serial I/O."), _("\
 701 Show parity for remote serial I/O."), NULL,
 702                         set_parity,
 703                         NULL, /* FIXME: i18n: */
 704                         &serial_set_cmdlist, &serial_show_cmdlist);
 705
 706   add_setshow_filename_cmd ("remotelogfile", no_class, &serial_logfile, _("\
 707 Set filename for remote session recording."), _("\
 708 Show filename for remote session recording."), _("\
 709 This file is used to record the remote session for future playback\n\
 710 by gdbserver."),
 711                             NULL,
 712                             NULL, /* FIXME: i18n: */
 713                             &setlist, &showlist);
 714
 715   add_setshow_enum_cmd ("remotelogbase", no_class, logbase_enums,
 716                         &serial_logbase, _("\
 717 Set numerical base for remote session logging."), _("\
 718 Show numerical base for remote session logging."), NULL,
 719                         NULL,
 720                         NULL, /* FIXME: i18n: */
 721                         &setlist, &showlist);
 722
 723   add_setshow_zuinteger_cmd ("serial", class_maintenance,
 724                              &global_serial_debug_p, _("\
 725 Set serial debugging."), _("\
 726 Show serial debugging."), _("\
 727 When non-zero, serial port debugging is enabled."),
 728                              NULL,
 729                              NULL, /* FIXME: i18n: */
 730                              &setdebuglist, &showdebuglist);
 731 }