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 <termios.h>
   9 #include <unistd.h>
  10 #include <fcntl.h>
  11 #include <string.h>
  12 #include <sys/poll.h>
  13 #include <sys/ioctl.h>
  14 #include <errno.h>
  15
  16 #include <glib.h>
  17
  18 /* This is for FIONREAD on solaris */
  19 #if defined(sun)
  20 #include <sys/filio.h>
  21 #endif
  22
  23 /* sys/time.h (for timeval) is required when using osx 10.3 (but not 10.4) */
  24 #ifdef __APPLE__
  25 #include <sys/time.h>
  26 #endif
  27
  28 /* This is a copy of System.IO.Ports.Handshake */
  29 typedef enum {
  30         NoneHandshake = 0,
  31         XOnXOff = 1,
  32         RequestToSend = 2,
  33         RequestToSendXOnXOff = 3
  34 } MonoHandshake;
  35
  36 /* This is a copy of System.IO.Ports.Parity */
  37 typedef enum {
  38         NoneParity = 0,
  39         Odd = 1,
  40         Even = 2,
  41         Mark = 3,
  42         Space = 4
  43 } MonoParity;
  44
  45 /* This is a copy of System.IO.Ports.StopBits */
  46 typedef enum {
  47         NoneStopBits = 0,
  48         One = 1,
  49         Two = 2,
  50         OnePointFive = 3
  51 } MonoStopBits;
  52
  53 /* This is a copy of System.IO.Ports.SerialSignal */
  54 typedef enum {
  55         NoneSignal,
  56         Cd = 1, /* Carrier detect */
  57         Cts = 2, /* Clear to send */
  58         Dsr = 4, /* Data set ready */
  59         Dtr = 8, /* Data terminal ready */
  60         Rts = 16  /* Request to send */
  61 } MonoSerialSignal;
  62
  63 int
  64 open_serial (char* devfile)
  65 {
  66         int fd;
  67         fd = open (devfile, O_RDWR | O_NOCTTY | O_NONBLOCK);
  68
  69         return fd;
  70 }
  71
  72 int
  73 close_serial (int unix_fd)
  74 {
  75         // Linus writes: do not retry close after EINTR
  76         return close (unix_fd);
  77 }
  78
  79 guint32
  80 read_serial (int fd, guchar *buffer, int offset, int count)
  81 {
  82         guint32 n;
  83
  84         n = read (fd, buffer + offset, count);
  85
  86         return (guint32) n;
  87 }
  88
  89 int
  90 write_serial (int fd, guchar *buffer, int offset, int count, int timeout)
  91 {
  92         struct pollfd pinfo;
  93         guint32 n;
  94
  95         pinfo.fd = fd;
  96         pinfo.events = POLLOUT;
  97         pinfo.revents = POLLOUT;
  98
  99         n = count;
 100
 101         while (n > 0)
 102         {
 103                 size_t t;
 104
 105                 if (timeout != 0) {
 106                         int c;
 107
 108                         while ((c = poll (&pinfo, 1, timeout)) == -1 && errno == EINTR)
 109                                 ;
 110                         if (c == -1)
 111                                 return -1;
 112                 }
 113
 114                 do {
 115                         t = write (fd, buffer + offset, n);
 116                 } while (t == -1 && errno == EINTR);
 117
 118                 if (t < 0)
 119                         return -1;
 120
 121                 offset += t;
 122                 n -= t;
 123         }
 124
 125         return 0;
 126 }
 127
 128 int
 129 discard_buffer (int fd, gboolean input)
 130 {
 131         return tcflush(fd, input ? TCIFLUSH : TCOFLUSH);
 132 }
 133
 134 gint32
 135 get_bytes_in_buffer (int fd, gboolean input)
 136 {
 137         gint32 retval;
 138
 139         if (ioctl (fd, input ? FIONREAD : TIOCOUTQ, &retval) == -1) {
 140                 return -1;
 141         }
 142
 143         return retval;
 144 }
 145
 146 gboolean
 147 set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake)
 148 {
 149         struct termios newtio;
 150
 151         if (tcgetattr (fd, &newtio) == -1)
 152                 return FALSE;
 153
 154         newtio.c_cflag |=  (CLOCAL | CREAD);
 155         newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL | ISIG | IEXTEN );
 156         newtio.c_oflag &= ~(OPOST);
 157         newtio.c_iflag = IGNBRK;
 158
 159         /* setup baudrate */
 160         switch (baud_rate)
 161         {
 162 /*Some values are not defined on OSX and *BSD */
 163 #if defined(B921600)
 164         case 921600:
 165             baud_rate = B921600;
 166             break;
 167 #endif
 168 #if defined(B460800)
 169         case 460800:
 170             baud_rate = B460800;
 171             break;
 172 #endif
 173         case 230400:
 174             baud_rate = B230400;
 175             break;
 176         case 115200:
 177             baud_rate = B115200;
 178             break;
 179         case 57600:
 180             baud_rate = B57600;
 181             break;
 182         case 38400:
 183             baud_rate = B38400;
 184             break;
 185         case 19200:
 186             baud_rate = B19200;
 187             break;
 188         case 9600:
 189                 baud_rate = B9600;
 190                 break;
 191         case 4800:
 192             baud_rate = B4800;
 193                 break;
 194         case 2400:
 195             baud_rate = B2400;
 196                 break;
 197         case 1800:
 198             baud_rate = B1800;
 199                 break;
 200         case 1200:
 201             baud_rate = B1200;
 202                 break;
 203         case 600:
 204             baud_rate = B600;
 205             break;
 206         case 300:
 207             baud_rate = B300;
 208             break;
 209         case 200:
 210             baud_rate = B200;
 211             break;
 212         case 150:
 213             baud_rate = B150;
 214             break;
 215         case 134:
 216             baud_rate = B134;
 217             break;
 218         case 110:
 219             baud_rate = B110;
 220             break;
 221         case 75:
 222             baud_rate = B75;
 223             break;
 224         case 50:
 225         case 0:
 226         default:
 227             baud_rate = B9600;
 228                 break;
 229         }
 230
 231         /* char lenght */
 232         newtio.c_cflag &= ~CSIZE;
 233         switch (dataBits)
 234         {
 235         case 5:
 236             newtio.c_cflag |= CS5;
 237             break;
 238         case 6:
 239             newtio.c_cflag |= CS6;
 240             break;
 241         case 7:
 242             newtio.c_cflag |= CS7;
 243             break;
 244         case 8:
 245         default:
 246                 newtio.c_cflag |= CS8;
 247                 break;
 248         }
 249
 250         /* stopbits */
 251         switch (stopBits)
 252         {
 253         case NoneStopBits:
 254                 /* Unhandled */
 255                 break;
 256         case One: /* One */
 257                 /* do nothing, the default is one stop bit */
 258             newtio.c_cflag &= ~CSTOPB;
 259                 break;
 260         case Two: /* Two */
 261                 newtio.c_cflag |= CSTOPB;
 262                 break;
 263         case OnePointFive: /* OnePointFive */
 264                 /* XXX unhandled */
 265                 break;
 266         }
 267
 268         /* parity */
 269         newtio.c_iflag &= ~(INPCK | ISTRIP );
 270
 271         switch (parity)
 272         {
 273         case NoneParity: /* None */
 274             newtio.c_cflag &= ~(PARENB | PARODD);
 275             break;
 276
 277         case Odd: /* Odd */
 278             newtio.c_cflag |= PARENB | PARODD;
 279             break;
 280
 281         case Even: /* Even */
 282             newtio.c_cflag &= ~(PARODD);
 283             newtio.c_cflag |= (PARENB);
 284             break;
 285
 286         case Mark: /* Mark */
 287             /* XXX unhandled */
 288             break;
 289         case Space: /* Space */
 290             /* XXX unhandled */
 291             break;
 292         }
 293
 294         newtio.c_iflag &= ~(IXOFF | IXON);
 295 #ifdef CRTSCTS
 296         newtio.c_cflag &= ~CRTSCTS;
 297 #endif /* def CRTSCTS */
 298
 299         switch (handshake)
 300         {
 301         case NoneHandshake: /* None */
 302                 /* do nothing */
 303                 break;
 304         case RequestToSend: /* RequestToSend (RTS) */
 305 #ifdef CRTSCTS
 306                 newtio.c_cflag |= CRTSCTS;
 307 #endif /* def CRTSCTS */
 308                 break;
 309         case RequestToSendXOnXOff: /* RequestToSendXOnXOff (RTS + XON/XOFF) */
 310 #ifdef CRTSCTS
 311                 newtio.c_cflag |= CRTSCTS;
 312 #endif /* def CRTSCTS */
 313                 /* fall through */
 314         case XOnXOff: /* XOnXOff */
 315             newtio.c_iflag |= IXOFF | IXON;
 316                 break;
 317         }
 318
 319         if (cfsetospeed (&newtio, baud_rate) < 0 || cfsetispeed (&newtio, baud_rate) < 0 ||
 320             tcsetattr (fd, TCSANOW, &newtio) < 0)
 321         {
 322                 return FALSE;
 323         }
 324         else
 325         {
 326         return TRUE;
 327         }
 328 }
 329
 330
 331 static gint32
 332 get_signal_code (MonoSerialSignal signal)
 333 {
 334         switch (signal) {
 335                 case Cd:
 336                         return TIOCM_CAR;
 337                 case Cts:
 338                         return TIOCM_CTS;
 339                 case Dsr:
 340                         return TIOCM_DSR;
 341                 case Dtr:
 342                         return TIOCM_DTR;
 343                 case Rts:
 344                         return TIOCM_RTS;
 345                 default:
 346                         return 0;
 347         }
 348
 349         /* Not reached */
 350         return 0;
 351 }
 352
 353 static MonoSerialSignal
 354 get_mono_signal_codes (int signals)
 355 {
 356         MonoSerialSignal retval = NoneSignal;
 357
 358         if ((signals & TIOCM_CAR) != 0)
 359                 retval |= Cd;
 360         if ((signals & TIOCM_CTS) != 0)
 361                 retval |= Cts;
 362         if ((signals & TIOCM_DSR) != 0)
 363                 retval |= Dsr;
 364         if ((signals & TIOCM_DTR) != 0)
 365                 retval |= Dtr;
 366         if ((signals & TIOCM_RTS) != 0)
 367                 retval |= Rts;
 368
 369         return retval;
 370 }
 371
 372 MonoSerialSignal
 373 get_signals (int fd, gint32 *error)
 374 {
 375         int signals;
 376
 377         *error = 0;
 378
 379         if (ioctl (fd, TIOCMGET, &signals) == -1) {
 380                 *error = -1;
 381                 return NoneSignal;
 382         }
 383
 384         return get_mono_signal_codes (signals);
 385 }
 386
 387 gint32
 388 set_signal (int fd, MonoSerialSignal signal, gboolean value)
 389 {
 390         int signals, expected, activated;
 391
 392         expected = get_signal_code (signal);
 393         if (ioctl (fd, TIOCMGET, &signals) == -1)
 394                 return -1;
 395
 396         activated = (signals & expected) != 0;
 397         if (activated == value) /* Already set */
 398                 return 1;
 399
 400         if (value)
 401                 signals |= expected;
 402         else
 403                 signals &= ~expected;
 404
 405         if (ioctl (fd, TIOCMSET, &signals) == -1)
 406                 return -1;
 407
 408         return 1;
 409 }
 410
 411 int
 412 breakprop (int fd)
 413 {
 414         return tcsendbreak (fd, 0);
 415 }
 416
 417 gboolean
 418 poll_serial (int fd, gint32 *error, int timeout)
 419 {
 420         struct pollfd pinfo;
 421
 422         *error = 0;
 423
 424         pinfo.fd = fd;
 425         pinfo.events = POLLIN;
 426         pinfo.revents = 0;
 427
 428         while (poll (&pinfo, 1, timeout) == -1 && errno == EINTR) {
 429                 /* EINTR is an OK condition, we should not throw in the upper layer an IOException */
 430                 if (errno != EINTR){
 431                         *error = -1;
 432                         return FALSE;
 433                 }
 434         }
 435
 436         return (pinfo.revents & POLLIN) != 0 ? 1 : 0;
 437 }
 438
 439 /*
 440  * mono internals should not be used here.
 441  * this serial stuff needs to be implemented with icalls.
 442  * make this at least compile until the code is moved elsewhere
 443  * defined(linux) is wrong, too
 444  */
 445 void*
 446 list_serial_devices (void)
 447 {
 448         return NULL;
 449 }
 450
 451 #if 0
 452 MonoArray *
 453 list_serial_devices (void)
 454 {
 455         MonoArray *array;
 456 #if defined(linux)
 457         /* Linux serial files are of the form ttyS[0-9]+ */
 458         GSList *l, *list = NULL;
 459         GDir* dir = g_dir_open ("/dev", 0, NULL);
 460         const char *filename;
 461         int i = 0;
 462
 463         while ((filename = g_dir_read_name (dir))) {
 464                 if (filename) {
 465                         if (!strncmp (filename, "ttyS", 4))
 466                                 list = g_slist_append (list, g_strconcat ("/dev/", filename, NULL));
 467                 }
 468         }
 469
 470         g_dir_close (dir);
 471
 472         array = mono_array_new (mono_domain_get (), mono_get_string_class (), g_slist_length (list));
 473         for (l = list; l; l = l->next) {
 474                 mono_array_set (array, gpointer, i++, mono_string_new (mono_domain_get (), (char*)l->data));
 475                 g_free (l->data);
 476         }
 477
 478         g_slist_free (list);
 479
 480 #else
 481 #warning "list_serial_devices isn't ported to this OS"
 482 #endif
 483
 484         return array;
 485 }
 486 #endif
 487