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