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 /*This is not defined on OSX and *BSD */
 163 #if defined(B460800)
 164         case 460800:
 165             baud_rate = B460800;
 166             break;
 167 #endif
 168         case 230400:
 169             baud_rate = B230400;
 170             break;
 171         case 115200:
 172             baud_rate = B115200;
 173             break;
 174         case 57600:
 175             baud_rate = B57600;
 176             break;
 177         case 38400:
 178             baud_rate = B38400;
 179             break;
 180         case 19200:
 181             baud_rate = B19200;
 182             break;
 183         case 9600:
 184                 baud_rate = B9600;
 185                 break;
 186         case 4800:
 187             baud_rate = B4800;
 188                 break;
 189         case 2400:
 190             baud_rate = B2400;
 191                 break;
 192         case 1800:
 193             baud_rate = B1800;
 194                 break;
 195         case 1200:
 196             baud_rate = B1200;
 197                 break;
 198         case 600:
 199             baud_rate = B600;
 200             break;
 201         case 300:
 202             baud_rate = B300;
 203             break;
 204         case 200:
 205             baud_rate = B200;
 206             break;
 207         case 150:
 208             baud_rate = B150;
 209             break;
 210         case 134:
 211             baud_rate = B134;
 212             break;
 213         case 110:
 214             baud_rate = B110;
 215             break;
 216         case 75:
 217             baud_rate = B75;
 218             break;
 219         case 50:
 220         case 0:
 221         default:
 222             baud_rate = B9600;
 223                 break;
 224         }
 225
 226         /* char lenght */
 227         newtio.c_cflag &= ~CSIZE;
 228         switch (dataBits)
 229         {
 230         case 5:
 231             newtio.c_cflag |= CS5;
 232             break;
 233         case 6:
 234             newtio.c_cflag |= CS6;
 235             break;
 236         case 7:
 237             newtio.c_cflag |= CS7;
 238             break;
 239         case 8:
 240         default:
 241                 newtio.c_cflag |= CS8;
 242                 break;
 243         }
 244
 245         /* stopbits */
 246         switch (stopBits)
 247         {
 248         case NoneStopBits:
 249                 /* Unhandled */
 250                 break;
 251         case One: /* One */
 252                 /* do nothing, the default is one stop bit */
 253             newtio.c_cflag &= ~CSTOPB;
 254                 break;
 255         case Two: /* Two */
 256                 newtio.c_cflag |= CSTOPB;
 257                 break;
 258         case OnePointFive: /* OnePointFive */
 259                 /* XXX unhandled */
 260                 break;
 261         }
 262
 263         /* parity */
 264         newtio.c_iflag &= ~(INPCK | ISTRIP );
 265
 266         switch (parity)
 267         {
 268         case NoneParity: /* None */
 269             newtio.c_cflag &= ~(PARENB | PARODD);
 270             break;
 271
 272         case Odd: /* Odd */
 273             newtio.c_cflag |= PARENB | PARODD;
 274             break;
 275
 276         case Even: /* Even */
 277             newtio.c_cflag &= ~(PARODD);
 278             newtio.c_cflag |= (PARENB);
 279             break;
 280
 281         case Mark: /* Mark */
 282             /* XXX unhandled */
 283             break;
 284         case Space: /* Space */
 285             /* XXX unhandled */
 286             break;
 287         }
 288
 289         newtio.c_iflag &= ~(IXOFF | IXON);
 290 #ifdef CRTSCTS
 291         newtio.c_cflag &= ~CRTSCTS;
 292 #endif /* def CRTSCTS */
 293
 294         switch (handshake)
 295         {
 296         case NoneHandshake: /* None */
 297                 /* do nothing */
 298                 break;
 299         case RequestToSend: /* RequestToSend (RTS) */
 300 #ifdef CRTSCTS
 301                 newtio.c_cflag |= CRTSCTS;
 302 #endif /* def CRTSCTS */
 303                 break;
 304         case RequestToSendXOnXOff: /* RequestToSendXOnXOff (RTS + XON/XOFF) */
 305 #ifdef CRTSCTS
 306                 newtio.c_cflag |= CRTSCTS;
 307 #endif /* def CRTSCTS */
 308                 /* fall through */
 309         case XOnXOff: /* XOnXOff */
 310             newtio.c_iflag |= IXOFF | IXON;
 311                 break;
 312         }
 313
 314         if (cfsetospeed (&newtio, baud_rate) < 0 || cfsetispeed (&newtio, baud_rate) < 0 ||
 315             tcsetattr (fd, TCSANOW, &newtio) < 0)
 316         {
 317                 return FALSE;
 318         }
 319         else
 320         {
 321         return TRUE;
 322         }
 323 }
 324
 325
 326 static gint32
 327 get_signal_code (MonoSerialSignal signal)
 328 {
 329         switch (signal) {
 330                 case Cd:
 331                         return TIOCM_CAR;
 332                 case Cts:
 333                         return TIOCM_CTS;
 334                 case Dsr:
 335                         return TIOCM_DSR;
 336                 case Dtr:
 337                         return TIOCM_DTR;
 338                 case Rts:
 339                         return TIOCM_RTS;
 340                 default:
 341                         return 0;
 342         }
 343
 344         /* Not reached */
 345         return 0;
 346 }
 347
 348 static MonoSerialSignal
 349 get_mono_signal_codes (int signals)
 350 {
 351         MonoSerialSignal retval = NoneSignal;
 352
 353         if ((signals & TIOCM_CAR) != 0)
 354                 retval |= Cd;
 355         if ((signals & TIOCM_CTS) != 0)
 356                 retval |= Cts;
 357         if ((signals & TIOCM_DSR) != 0)
 358                 retval |= Dsr;
 359         if ((signals & TIOCM_DTR) != 0)
 360                 retval |= Dtr;
 361         if ((signals & TIOCM_RTS) != 0)
 362                 retval |= Rts;
 363
 364         return retval;
 365 }
 366
 367 MonoSerialSignal
 368 get_signals (int fd, gint32 *error)
 369 {
 370         int signals;
 371
 372         *error = 0;
 373
 374         if (ioctl (fd, TIOCMGET, &signals) == -1) {
 375                 *error = -1;
 376                 return NoneSignal;
 377         }
 378
 379         return get_mono_signal_codes (signals);
 380 }
 381
 382 gint32
 383 set_signal (int fd, MonoSerialSignal signal, gboolean value)
 384 {
 385         int signals, expected, activated;
 386
 387         expected = get_signal_code (signal);
 388         if (ioctl (fd, TIOCMGET, &signals) == -1)
 389                 return -1;
 390
 391         activated = (signals & expected) != 0;
 392         if (activated == value) /* Already set */
 393                 return 1;
 394
 395         if (value)
 396                 signals |= expected;
 397         else
 398                 signals &= ~expected;
 399
 400         if (ioctl (fd, TIOCMSET, &signals) == -1)
 401                 return -1;
 402
 403         return 1;
 404 }
 405
 406 int
 407 breakprop (int fd)
 408 {
 409         return tcsendbreak (fd, 0);
 410 }
 411
 412 gboolean
 413 poll_serial (int fd, gint32 *error, int timeout)
 414 {
 415         struct pollfd pinfo;
 416
 417         *error = 0;
 418
 419         pinfo.fd = fd;
 420         pinfo.events = POLLIN;
 421         pinfo.revents = 0;
 422
 423         while (poll (&pinfo, 1, timeout) == -1 && errno == EINTR) {
 424                 /* EINTR is an OK condition, we should not throw in the upper layer an IOException */
 425                 if (errno != EINTR){
 426                         *error = -1;
 427                         return FALSE;
 428                 }
 429         }
 430
 431         return (pinfo.revents & POLLIN) != 0 ? 1 : 0;
 432 }
 433
 434 /*
 435  * mono internals should not be used here.
 436  * this serial stuff needs to be implemented with icalls.
 437  * make this at least compile until the code is moved elsewhere
 438  * defined(linux) is wrong, too
 439  */
 440 void*
 441 list_serial_devices (void)
 442 {
 443         return NULL;
 444 }
 445
 446 #if 0
 447 MonoArray *
 448 list_serial_devices (void)
 449 {
 450         MonoArray *array;
 451 #if defined(linux)
 452         /* Linux serial files are of the form ttyS[0-9]+ */
 453         GSList *l, *list = NULL;
 454         GDir* dir = g_dir_open ("/dev", 0, NULL);
 455         const char *filename;
 456         int i = 0;
 457
 458         while ((filename = g_dir_read_name (dir))) {
 459                 if (filename) {
 460                         if (!strncmp (filename, "ttyS", 4))
 461                                 list = g_slist_append (list, g_strconcat ("/dev/", filename, NULL));
 462                 }
 463         }
 464
 465         g_dir_close (dir);
 466
 467         array = mono_array_new (mono_domain_get (), mono_get_string_class (), g_slist_length (list));
 468         for (l = list; l; l = l->next) {
 469                 mono_array_set (array, gpointer, i++, mono_string_new (mono_domain_get (), (char*)l->data));
 470                 g_free (l->data);
 471         }
 472
 473         g_slist_free (list);
 474
 475 #else
 476 #warning "list_serial_devices isn't ported to this OS"
 477 #endif
 478
 479         return array;
 480 }
 481 #endif
 482