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