support/serial.c

   1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
   2
   3 /* serial port functions
   4  *
   5  * Author: Chris Toshok <toshok@ximian.com>
   6  */
   7
   8 #include "map.h"
   9 #include "mph.h"
  10
  11 #include <termios.h>
  12 #include <unistd.h>
  13 #include <fcntl.h>
  14 #include <string.h>
  15 #include <errno.h>
  16 #if defined(HAVE_POLL_H)
  17 #include <poll.h>
  18 #elif defined(HAVE_SYS_POLL_H)
  19 #include <sys/poll.h>
  20 #endif
  21 #include <sys/ioctl.h>
  22
  23 /* This is for ASYNC_*, serial_struct on linux */
  24 #if defined(HAVE_LINUX_SERIAL_H)
  25 #include <linux/serial.h>
  26 #endif
  27
  28 #include <glib.h>
  29
  30 /* This is for FIONREAD on solaris */
  31 #if defined(sun)
  32 #include <sys/filio.h>
  33 #endif
  34
  35 /* sys/time.h (for timeval) is required when using osx 10.3 (but not 10.4) */
  36 /* IOKit is a private framework in iOS, so exclude there */
  37 #if defined(__APPLE__) && !defined(HOST_IOS) && !defined(HOST_WATCHOS) && !defined(HOST_APPLETVOS)
  38 #define HAVE_IOKIT 1
  39 #endif
  40
  41 #if defined(HAVE_IOKIT)
  42 #include <sys/time.h>
  43 #include <IOKit/IOKitLib.h>
  44 #include <IOKit/serial/IOSerialKeys.h>
  45 #include <IOKit/serial/ioss.h>
  46 #include <IOKit/IOBSD.h>
  47 #endif
  48
  49 /* This is a copy of System.IO.Ports.Handshake */
  50 typedef enum {
  51         NoneHandshake = 0,
  52         XOnXOff = 1,
  53         RequestToSend = 2,
  54         RequestToSendXOnXOff = 3
  55 } MonoHandshake;
  56
  57 /* This is a copy of System.IO.Ports.Parity */
  58 typedef enum {
  59         NoneParity = 0,
  60         Odd = 1,
  61         Even = 2,
  62         Mark = 3,
  63         Space = 4
  64 } MonoParity;
  65
  66 /* This is a copy of System.IO.Ports.StopBits */
  67 typedef enum {
  68         NoneStopBits = 0,
  69         One = 1,
  70         Two = 2,
  71         OnePointFive = 3
  72 } MonoStopBits;
  73
  74 /* This is a copy of System.IO.Ports.SerialSignal */
  75 typedef enum {
  76         NoneSignal,
  77         Cd = 1, /* Carrier detect */
  78         Cts = 2, /* Clear to send */
  79         Dsr = 4, /* Data set ready */
  80         Dtr = 8, /* Data terminal ready */
  81         Rts = 16  /* Request to send */
  82 } MonoSerialSignal;
  83
  84 /*
  85  * Silence the compiler, we do not need these prototypes to be public, since these are only
  86  * used by P/Invoke
  87  */
  88
  89 int              open_serial (char *devfile);
  90 int              close_serial (int unix_fd);
  91 guint32          read_serial (int fd, guchar *buffer, int offset, int count);
  92 int              write_serial (int fd, guchar *buffer, int offset, int count, int timeout);
  93 int              discard_buffer (int fd, gboolean input);
  94 gint32           get_bytes_in_buffer (int fd, gboolean input);
  95 gboolean         is_baud_rate_legal (int baud_rate);
  96 int              setup_baud_rate (int baud_rate, gboolean *custom_baud_rate);
  97 gboolean         set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake);
  98 MonoSerialSignal get_signals (int fd, gint32 *error);
  99 gint32           set_signal (int fd, MonoSerialSignal signal, gboolean value);
 100 int              breakprop (int fd);
 101 gboolean         poll_serial (int fd, gint32 *error, int timeout);
 102 void            *list_serial_devices (void);
 103
 104 int
 105 open_serial (char *devfile)
 106 {
 107         int fd;
 108         fd = open (devfile, O_RDWR | O_NOCTTY | O_NONBLOCK);
 109
 110         return fd;
 111 }
 112
 113 int
 114 close_serial (int unix_fd)
 115 {
 116         // Linus writes: do not retry close after EINTR
 117         return close (unix_fd);
 118 }
 119
 120 guint32
 121 read_serial (int fd, guchar *buffer, int offset, int count)
 122 {
 123         guint32 n;
 124
 125         n = read (fd, buffer + offset, count);
 126
 127         return (guint32) n;
 128 }
 129
 130 int
 131 write_serial (int fd, guchar *buffer, int offset, int count, int timeout)
 132 {
 133         struct pollfd pinfo;
 134         guint32 n;
 135
 136         pinfo.fd = fd;
 137         pinfo.events = POLLOUT;
 138         pinfo.revents = POLLOUT;
 139
 140         n = count;
 141
 142         while (n > 0)
 143         {
 144                 ssize_t t;
 145
 146                 if (timeout != 0) {
 147                         int c;
 148
 149                         while ((c = poll (&pinfo, 1, timeout)) == -1 && errno == EINTR)
 150                                 ;
 151                         if (c == -1)
 152                                 return -1;
 153                 }
 154
 155                 do {
 156                         t = write (fd, buffer + offset, n);
 157                 } while (t == -1 && errno == EINTR);
 158
 159                 if (t < 0)
 160                         return -1;
 161
 162                 offset += t;
 163                 n -= t;
 164         }
 165
 166         return 0;
 167 }
 168
 169 int
 170 discard_buffer (int fd, gboolean input)
 171 {
 172         return tcflush(fd, input ? TCIFLUSH : TCOFLUSH);
 173 }
 174
 175 gint32
 176 get_bytes_in_buffer (int fd, gboolean input)
 177 {
 178         gint32 retval;
 179
 180         if (ioctl (fd, input ? FIONREAD : TIOCOUTQ, &retval) == -1) {
 181                 return -1;
 182         }
 183
 184         return retval;
 185 }
 186
 187 gboolean
 188 is_baud_rate_legal (int baud_rate)
 189 {
 190         gboolean ignore = FALSE;
 191         return setup_baud_rate (baud_rate, &ignore) != -1;
 192 }
 193
 194 int
 195 setup_baud_rate (int baud_rate, gboolean *custom_baud_rate)
 196 {
 197         switch (baud_rate)
 198         {
 199 /*Some values are not defined on OSX and *BSD */
 200 #if defined(B921600)
 201         case 921600:
 202             baud_rate = B921600;
 203             break;
 204 #endif
 205 #if defined(B460800)
 206         case 460800:
 207             baud_rate = B460800;
 208             break;
 209 #endif
 210         case 230400:
 211             baud_rate = B230400;
 212             break;
 213         case 115200:
 214             baud_rate = B115200;
 215             break;
 216         case 57600:
 217             baud_rate = B57600;
 218             break;
 219         case 38400:
 220             baud_rate = B38400;
 221             break;
 222         case 19200:
 223             baud_rate = B19200;
 224             break;
 225         case 9600:
 226                 baud_rate = B9600;
 227                 break;
 228         case 4800:
 229             baud_rate = B4800;
 230                 break;
 231         case 2400:
 232             baud_rate = B2400;
 233                 break;
 234         case 1800:
 235             baud_rate = B1800;
 236                 break;
 237         case 1200:
 238             baud_rate = B1200;
 239                 break;
 240         case 600:
 241             baud_rate = B600;
 242             break;
 243         case 300:
 244             baud_rate = B300;
 245             break;
 246         case 200:
 247             baud_rate = B200;
 248             break;
 249         case 150:
 250             baud_rate = B150;
 251             break;
 252         case 134:
 253             baud_rate = B134;
 254             break;
 255         case 110:
 256             baud_rate = B110;
 257             break;
 258         case 75:
 259             baud_rate = B75;
 260             break;
 261         case 50:
 262 #ifdef B50
 263             baud_rate = B50;
 264 #else
 265             baud_rate = -1;
 266             break;
 267 #endif
 268         case 0:
 269 #ifdef B0
 270             baud_rate = B0;
 271 #else
 272             baud_rate = -1;
 273 #endif
 274             break;
 275         default:
 276                 *custom_baud_rate = TRUE;
 277                 break;
 278         }
 279         return baud_rate;
 280 }
 281
 282 gboolean
 283 set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake)
 284 {
 285         struct termios newtio;
 286         gboolean custom_baud_rate = FALSE;
 287
 288         if (tcgetattr (fd, &newtio) == -1)
 289                 return FALSE;
 290
 291         newtio.c_cflag |=  (CLOCAL | CREAD);
 292         newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL | ISIG | IEXTEN );
 293         newtio.c_oflag &= ~(OPOST);
 294         newtio.c_iflag = IGNBRK;
 295
 296         /* setup baudrate */
 297         baud_rate = setup_baud_rate (baud_rate, &custom_baud_rate);
 298
 299         /* char lenght */
 300         newtio.c_cflag &= ~CSIZE;
 301         switch (dataBits)
 302         {
 303         case 5:
 304             newtio.c_cflag |= CS5;
 305             break;
 306         case 6:
 307             newtio.c_cflag |= CS6;
 308             break;
 309         case 7:
 310             newtio.c_cflag |= CS7;
 311             break;
 312         case 8:
 313         default:
 314                 newtio.c_cflag |= CS8;
 315                 break;
 316         }
 317
 318         /* stopbits */
 319         switch (stopBits)
 320         {
 321         case NoneStopBits:
 322                 /* Unhandled */
 323                 break;
 324         case One: /* One */
 325                 /* do nothing, the default is one stop bit */
 326             newtio.c_cflag &= ~CSTOPB;
 327                 break;
 328         case Two: /* Two */
 329                 newtio.c_cflag |= CSTOPB;
 330                 break;
 331         case OnePointFive: /* OnePointFive */
 332                 /* XXX unhandled */
 333                 break;
 334         }
 335
 336         /* parity */
 337         newtio.c_iflag &= ~(INPCK | ISTRIP );
 338
 339         switch (parity)
 340         {
 341         case NoneParity: /* None */
 342             newtio.c_cflag &= ~(PARENB | PARODD);
 343             break;
 344
 345         case Odd: /* Odd */
 346             newtio.c_cflag |= PARENB | PARODD;
 347             break;
 348
 349         case Even: /* Even */
 350             newtio.c_cflag &= ~(PARODD);
 351             newtio.c_cflag |= (PARENB);
 352             break;
 353
 354         case Mark: /* Mark */
 355             /* XXX unhandled */
 356             break;
 357         case Space: /* Space */
 358             /* XXX unhandled */
 359             break;
 360         }
 361
 362         newtio.c_iflag &= ~(IXOFF | IXON);
 363 #ifdef CRTSCTS
 364         newtio.c_cflag &= ~CRTSCTS;
 365 #endif /* def CRTSCTS */
 366
 367         switch (handshake)
 368         {
 369         case NoneHandshake: /* None */
 370                 /* do nothing */
 371                 break;
 372         case RequestToSend: /* RequestToSend (RTS) */
 373 #ifdef CRTSCTS
 374                 newtio.c_cflag |= CRTSCTS;
 375 #endif /* def CRTSCTS */
 376                 break;
 377         case RequestToSendXOnXOff: /* RequestToSendXOnXOff (RTS + XON/XOFF) */
 378 #ifdef CRTSCTS
 379                 newtio.c_cflag |= CRTSCTS;
 380 #endif /* def CRTSCTS */
 381                 /* fall through */
 382         case XOnXOff: /* XOnXOff */
 383             newtio.c_iflag |= IXOFF | IXON;
 384                 break;
 385         }
 386
 387         if (custom_baud_rate == FALSE) {
 388                 if (cfsetospeed (&newtio, baud_rate) < 0 || cfsetispeed (&newtio, baud_rate) < 0)
 389                         return FALSE;
 390         } else {
 391 #if __linux__ || defined(HAVE_IOKIT)
 392
 393                 /* On Linux to set a custom baud rate, we must set the
 394                  * "standard" baud_rate to 38400.   On Apple we set it purely
 395                  * so that tcsetattr has something to use (and report back later), but
 396                  * the Apple specific API is still opaque to these APIs, see:
 397                  * https://developer.apple.com/library/mac/samplecode/SerialPortSample/Listings/SerialPortSample_SerialPortSample_c.html#//apple_ref/doc/uid/DTS10000454-SerialPortSample_SerialPortSample_c-DontLinkElementID_4
 398                  */
 399                 if (cfsetospeed (&newtio, B38400) < 0 || cfsetispeed (&newtio, B38400) < 0)
 400                         return FALSE;
 401 #endif
 402         }
 403
 404         if (tcsetattr (fd, TCSANOW, &newtio) < 0)
 405                 return FALSE;
 406
 407         if (custom_baud_rate == TRUE){
 408 #if defined(HAVE_LINUX_SERIAL_H)
 409                 struct serial_struct ser;
 410
 411                 if (ioctl (fd, TIOCGSERIAL, &ser) < 0)
 412                 {
 413                         return FALSE;
 414                 }
 415
 416                 ser.custom_divisor = ser.baud_base / baud_rate;
 417                 ser.flags &= ~ASYNC_SPD_MASK;
 418                 ser.flags |= ASYNC_SPD_CUST;
 419
 420                 if (ioctl (fd, TIOCSSERIAL, &ser) < 0)
 421                 {
 422                         return FALSE;
 423                 }
 424 #elif defined(HAVE_IOKIT)
 425                 speed_t speed = baud_rate;
 426                 if (ioctl(fd, IOSSIOSPEED, &speed) == -1)
 427                         return FALSE;
 428 #else
 429                 /* Don't know how to set custom baud rate on this platform. */
 430                 return FALSE;
 431 #endif
 432         }
 433
 434         return TRUE;
 435 }
 436
 437
 438 static gint32
 439 get_signal_code (MonoSerialSignal signal)
 440 {
 441         switch (signal) {
 442                 case Cd:
 443                         return TIOCM_CAR;
 444                 case Cts:
 445                         return TIOCM_CTS;
 446                 case Dsr:
 447                         return TIOCM_DSR;
 448                 case Dtr:
 449                         return TIOCM_DTR;
 450                 case Rts:
 451                         return TIOCM_RTS;
 452                 default:
 453                         return 0;
 454         }
 455
 456         /* Not reached */
 457         return 0;
 458 }
 459
 460 static MonoSerialSignal
 461 get_mono_signal_codes (int signals)
 462 {
 463         MonoSerialSignal retval = NoneSignal;
 464
 465         if ((signals & TIOCM_CAR) != 0)
 466                 retval |= Cd;
 467         if ((signals & TIOCM_CTS) != 0)
 468                 retval |= Cts;
 469         if ((signals & TIOCM_DSR) != 0)
 470                 retval |= Dsr;
 471         if ((signals & TIOCM_DTR) != 0)
 472                 retval |= Dtr;
 473         if ((signals & TIOCM_RTS) != 0)
 474                 retval |= Rts;
 475
 476         return retval;
 477 }
 478
 479 MonoSerialSignal
 480 get_signals (int fd, gint32 *error)
 481 {
 482         int signals;
 483
 484         *error = 0;
 485
 486         if (ioctl (fd, TIOCMGET, &signals) == -1) {
 487                 *error = -1;
 488                 return NoneSignal;
 489         }
 490
 491         return get_mono_signal_codes (signals);
 492 }
 493
 494 gint32
 495 set_signal (int fd, MonoSerialSignal signal, gboolean value)
 496 {
 497         int signals, expected, activated;
 498
 499         expected = get_signal_code (signal);
 500         if (ioctl (fd, TIOCMGET, &signals) == -1)
 501                 return -1;
 502
 503         activated = (signals & expected) != 0;
 504         if (activated == value) /* Already set */
 505                 return 1;
 506
 507         if (value)
 508                 signals |= expected;
 509         else
 510                 signals &= ~expected;
 511
 512         if (ioctl (fd, TIOCMSET, &signals) == -1)
 513                 return -1;
 514
 515         return 1;
 516 }
 517
 518 int
 519 breakprop (int fd)
 520 {
 521         return tcsendbreak (fd, 0);
 522 }
 523
 524 gboolean
 525 poll_serial (int fd, gint32 *error, int timeout)
 526 {
 527         struct pollfd pinfo;
 528
 529         *error = 0;
 530
 531         pinfo.fd = fd;
 532         pinfo.events = POLLIN;
 533         pinfo.revents = 0;
 534
 535         while (poll (&pinfo, 1, timeout) == -1 && errno == EINTR) {
 536                 /* EINTR is an OK condition, we should not throw in the upper layer an IOException */
 537                 if (errno != EINTR){
 538                         *error = -1;
 539                         return FALSE;
 540                 }
 541         }
 542
 543         return (pinfo.revents & POLLIN) != 0 ? 1 : 0;
 544 }
 545
 546 /*
 547  * mono internals should not be used here.
 548  * this serial stuff needs to be implemented with icalls.
 549  * make this at least compile until the code is moved elsewhere
 550  * defined(linux) is wrong, too
 551  */
 552 void*
 553 list_serial_devices (void)
 554 {
 555         return NULL;
 556 }
 557
 558 #if 0
 559 MonoArray *
 560 list_serial_devices (void)
 561 {
 562         MonoArray *array;
 563 #if defined(linux)
 564         /* Linux serial files are of the form ttyS[0-9]+ */
 565         GSList *l, *list = NULL;
 566         GDir* dir = g_dir_open ("/dev", 0, NULL);
 567         const char *filename;
 568         int i = 0;
 569
 570         while ((filename = g_dir_read_name (dir))) {
 571                 if (filename) {
 572                         if (!strncmp (filename, "ttyS", 4))
 573                                 list = g_slist_append (list, g_strconcat ("/dev/", filename, NULL));
 574                 }
 575         }
 576
 577         g_dir_close (dir);
 578
 579         array = mono_array_new (mono_domain_get (), mono_get_string_class (), g_slist_length (list));
 580         for (l = list; l; l = l->next) {
 581                 mono_array_set (array, gpointer, i++, mono_string_new (mono_domain_get (), (char*)l->data));
 582                 g_free (l->data);
 583         }
 584
 585         g_slist_free (list);
 586
 587 #else
 588 #warning "list_serial_devices isn't ported to this OS"
 589 #endif
 590
 591         return array;
 592 }
 593 #endif
 594