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 <errno.h>
  13 #if defined(__APPLE__)
  14 #include "fakepoll.h"
  15 #else
  16 #include <sys/poll.h>
  17 #endif
  18 #include <sys/ioctl.h>
  19
  20 #include <glib.h>
  21
  22 /* This is for FIONREAD on solaris */
  23 #if defined(sun)
  24 #include <sys/filio.h>
  25 #endif
  26
  27 /* sys/time.h (for timeval) is required when using osx 10.3 (but not 10.4) */
  28 #ifdef __APPLE__
  29 #include <sys/time.h>
  30 #endif
  31
  32 /* This is a copy of System.IO.Ports.Handshake */
  33 typedef enum {
  34         NoneHandshake = 0,
  35         XOnXOff = 1,
  36         RequestToSend = 2,
  37         RequestToSendXOnXOff = 3
  38 } MonoHandshake;
  39
  40 /* This is a copy of System.IO.Ports.Parity */
  41 typedef enum {
  42         NoneParity = 0,
  43         Odd = 1,
  44         Even = 2,
  45         Mark = 3,
  46         Space = 4
  47 } MonoParity;
  48
  49 /* This is a copy of System.IO.Ports.StopBits */
  50 typedef enum {
  51         NoneStopBits = 0,
  52         One = 1,
  53         Two = 2,
  54         OnePointFive = 3
  55 } MonoStopBits;
  56
  57 /* This is a copy of System.IO.Ports.SerialSignal */
  58 typedef enum {
  59         NoneSignal,
  60         Cd = 1, /* Carrier detect */
  61         Cts = 2, /* Clear to send */
  62         Dsr = 4, /* Data set ready */
  63         Dtr = 8, /* Data terminal ready */
  64         Rts = 16  /* Request to send */
  65 } MonoSerialSignal;
  66
  67 int
  68 open_serial (char* devfile)
  69 {
  70         int fd;
  71         fd = open (devfile, O_RDWR | O_NOCTTY | O_NONBLOCK);
  72
  73         return fd;
  74 }
  75
  76 int
  77 close_serial (int unix_fd)
  78 {
  79         // Linus writes: do not retry close after EINTR
  80         return close (unix_fd);
  81 }
  82
  83 guint32
  84 read_serial (int fd, guchar *buffer, int offset, int count)
  85 {
  86         guint32 n;
  87
  88         n = read (fd, buffer + offset, count);
  89
  90         return (guint32) n;
  91 }
  92
  93 int
  94 write_serial (int fd, guchar *buffer, int offset, int count, int timeout)
  95 {
  96         struct pollfd pinfo;
  97         guint32 n;
  98
  99         pinfo.fd = fd;
 100         pinfo.events = POLLOUT;
 101         pinfo.revents = POLLOUT;
 102
 103         n = count;
 104
 105         while (n > 0)
 106         {
 107                 size_t t;
 108
 109                 if (timeout != 0) {
 110                         int c;
 111
 112                         while ((c = poll (&pinfo, 1, timeout)) == -1 && errno == EINTR)
 113                                 ;
 114                         if (c == -1)
 115                                 return -1;
 116                 }
 117
 118                 do {
 119                         t = write (fd, buffer + offset, n);
 120                 } while (t == -1 && errno == EINTR);
 121
 122                 if (t < 0)
 123                         return -1;
 124
 125                 offset += t;
 126                 n -= t;
 127         }
 128
 129         return 0;
 130 }
 131
 132 int
 133 discard_buffer (int fd, gboolean input)
 134 {
 135         return tcflush(fd, input ? TCIFLUSH : TCOFLUSH);
 136 }
 137
 138 gint32
 139 get_bytes_in_buffer (int fd, gboolean input)
 140 {
 141         gint32 retval;
 142
 143         if (ioctl (fd, input ? FIONREAD : TIOCOUTQ, &retval) == -1) {
 144                 return -1;
 145         }
 146
 147         return retval;
 148 }
 149
 150 gboolean
 151 set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake)
 152 {
 153         struct termios newtio;
 154
 155         if (tcgetattr (fd, &newtio) == -1)
 156                 return FALSE;
 157
 158         newtio.c_cflag |=  (CLOCAL | CREAD);
 159         newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL | ISIG | IEXTEN );
 160         newtio.c_oflag &= ~(OPOST);
 161         newtio.c_iflag = IGNBRK;
 162
 163         /* setup baudrate */
 164         switch (baud_rate)
 165         {
 166 /*Some values are not defined on OSX and *BSD */
 167 #if defined(B921600)
 168         case 921600:
 169             baud_rate = B921600;
 170             break;
 171 #endif
 172 #if defined(B460800)
 173         case 460800:
 174             baud_rate = B460800;
 175             break;
 176 #endif
 177         case 230400:
 178             baud_rate = B230400;
 179             break;
 180         case 115200:
 181             baud_rate = B115200;
 182             break;
 183         case 57600:
 184             baud_rate = B57600;
 185             break;
 186         case 38400:
 187             baud_rate = B38400;
 188             break;
 189         case 19200:
 190             baud_rate = B19200;
 191             break;
 192         case 9600:
 193                 baud_rate = B9600;
 194                 break;
 195         case 4800:
 196             baud_rate = B4800;
 197                 break;
 198         case 2400:
 199             baud_rate = B2400;
 200                 break;
 201         case 1800:
 202             baud_rate = B1800;
 203                 break;
 204         case 1200:
 205             baud_rate = B1200;
 206                 break;
 207         case 600:
 208             baud_rate = B600;
 209             break;
 210         case 300:
 211             baud_rate = B300;
 212             break;
 213         case 200:
 214             baud_rate = B200;
 215             break;
 216         case 150:
 217             baud_rate = B150;
 218             break;
 219         case 134:
 220             baud_rate = B134;
 221             break;
 222         case 110:
 223             baud_rate = B110;
 224             break;
 225         case 75:
 226             baud_rate = B75;
 227             break;
 228         case 50:
 229         case 0:
 230         default:
 231             baud_rate = B9600;
 232                 break;
 233         }
 234
 235         /* char lenght */
 236         newtio.c_cflag &= ~CSIZE;
 237         switch (dataBits)
 238         {
 239         case 5:
 240             newtio.c_cflag |= CS5;
 241             break;
 242         case 6:
 243             newtio.c_cflag |= CS6;
 244             break;
 245         case 7:
 246             newtio.c_cflag |= CS7;
 247             break;
 248         case 8:
 249         default:
 250                 newtio.c_cflag |= CS8;
 251                 break;
 252         }
 253
 254         /* stopbits */
 255         switch (stopBits)
 256         {
 257         case NoneStopBits:
 258                 /* Unhandled */
 259                 break;
 260         case One: /* One */
 261                 /* do nothing, the default is one stop bit */
 262             newtio.c_cflag &= ~CSTOPB;
 263                 break;
 264         case Two: /* Two */
 265                 newtio.c_cflag |= CSTOPB;
 266                 break;
 267         case OnePointFive: /* OnePointFive */
 268                 /* XXX unhandled */
 269                 break;
 270         }
 271
 272         /* parity */
 273         newtio.c_iflag &= ~(INPCK | ISTRIP );
 274
 275         switch (parity)
 276         {
 277         case NoneParity: /* None */
 278             newtio.c_cflag &= ~(PARENB | PARODD);
 279             break;
 280
 281         case Odd: /* Odd */
 282             newtio.c_cflag |= PARENB | PARODD;
 283             break;
 284
 285         case Even: /* Even */
 286             newtio.c_cflag &= ~(PARODD);
 287             newtio.c_cflag |= (PARENB);
 288             break;
 289
 290         case Mark: /* Mark */
 291             /* XXX unhandled */
 292             break;
 293         case Space: /* Space */
 294             /* XXX unhandled */
 295             break;
 296         }
 297
 298         newtio.c_iflag &= ~(IXOFF | IXON);
 299 #ifdef CRTSCTS
 300         newtio.c_cflag &= ~CRTSCTS;
 301 #endif /* def CRTSCTS */
 302
 303         switch (handshake)
 304         {
 305         case NoneHandshake: /* None */
 306                 /* do nothing */
 307                 break;
 308         case RequestToSend: /* RequestToSend (RTS) */
 309 #ifdef CRTSCTS
 310                 newtio.c_cflag |= CRTSCTS;
 311 #endif /* def CRTSCTS */
 312                 break;
 313         case RequestToSendXOnXOff: /* RequestToSendXOnXOff (RTS + XON/XOFF) */
 314 #ifdef CRTSCTS
 315                 newtio.c_cflag |= CRTSCTS;
 316 #endif /* def CRTSCTS */
 317                 /* fall through */
 318         case XOnXOff: /* XOnXOff */
 319             newtio.c_iflag |= IXOFF | IXON;
 320                 break;
 321         }
 322
 323         if (cfsetospeed (&newtio, baud_rate) < 0 || cfsetispeed (&newtio, baud_rate) < 0 ||
 324             tcsetattr (fd, TCSANOW, &newtio) < 0)
 325         {
 326                 return FALSE;
 327         }
 328         else
 329         {
 330         return TRUE;
 331         }
 332 }
 333
 334
 335 static gint32
 336 get_signal_code (MonoSerialSignal signal)
 337 {
 338         switch (signal) {
 339                 case Cd:
 340                         return TIOCM_CAR;
 341                 case Cts:
 342                         return TIOCM_CTS;
 343                 case Dsr:
 344                         return TIOCM_DSR;
 345                 case Dtr:
 346                         return TIOCM_DTR;
 347                 case Rts:
 348                         return TIOCM_RTS;
 349                 default:
 350                         return 0;
 351         }
 352
 353         /* Not reached */
 354         return 0;
 355 }
 356
 357 static MonoSerialSignal
 358 get_mono_signal_codes (int signals)
 359 {
 360         MonoSerialSignal retval = NoneSignal;
 361
 362         if ((signals & TIOCM_CAR) != 0)
 363                 retval |= Cd;
 364         if ((signals & TIOCM_CTS) != 0)
 365                 retval |= Cts;
 366         if ((signals & TIOCM_DSR) != 0)
 367                 retval |= Dsr;
 368         if ((signals & TIOCM_DTR) != 0)
 369                 retval |= Dtr;
 370         if ((signals & TIOCM_RTS) != 0)
 371                 retval |= Rts;
 372
 373         return retval;
 374 }
 375
 376 MonoSerialSignal
 377 get_signals (int fd, gint32 *error)
 378 {
 379         int signals;
 380
 381         *error = 0;
 382
 383         if (ioctl (fd, TIOCMGET, &signals) == -1) {
 384                 *error = -1;
 385                 return NoneSignal;
 386         }
 387
 388         return get_mono_signal_codes (signals);
 389 }
 390
 391 gint32
 392 set_signal (int fd, MonoSerialSignal signal, gboolean value)
 393 {
 394         int signals, expected, activated;
 395
 396         expected = get_signal_code (signal);
 397         if (ioctl (fd, TIOCMGET, &signals) == -1)
 398                 return -1;
 399
 400         activated = (signals & expected) != 0;
 401         if (activated == value) /* Already set */
 402                 return 1;
 403
 404         if (value)
 405                 signals |= expected;
 406         else
 407                 signals &= ~expected;
 408
 409         if (ioctl (fd, TIOCMSET, &signals) == -1)
 410                 return -1;
 411
 412         return 1;
 413 }
 414
 415 int
 416 breakprop (int fd)
 417 {
 418         return tcsendbreak (fd, 0);
 419 }
 420
 421 gboolean
 422 poll_serial (int fd, gint32 *error, int timeout)
 423 {
 424         struct pollfd pinfo;
 425
 426         *error = 0;
 427
 428         pinfo.fd = fd;
 429         pinfo.events = POLLIN;
 430         pinfo.revents = 0;
 431
 432         while (poll (&pinfo, 1, timeout) == -1 && errno == EINTR) {
 433                 /* EINTR is an OK condition, we should not throw in the upper layer an IOException */
 434                 if (errno != EINTR){
 435                         *error = -1;
 436                         return FALSE;
 437                 }
 438         }
 439
 440         return (pinfo.revents & POLLIN) != 0 ? 1 : 0;
 441 }
 442
 443 /*
 444  * mono internals should not be used here.
 445  * this serial stuff needs to be implemented with icalls.
 446  * make this at least compile until the code is moved elsewhere
 447  * defined(linux) is wrong, too
 448  */
 449 void*
 450 list_serial_devices (void)
 451 {
 452         return NULL;
 453 }
 454
 455 #if 0
 456 MonoArray *
 457 list_serial_devices (void)
 458 {
 459         MonoArray *array;
 460 #if defined(linux)
 461         /* Linux serial files are of the form ttyS[0-9]+ */
 462         GSList *l, *list = NULL;
 463         GDir* dir = g_dir_open ("/dev", 0, NULL);
 464         const char *filename;
 465         int i = 0;
 466
 467         while ((filename = g_dir_read_name (dir))) {
 468                 if (filename) {
 469                         if (!strncmp (filename, "ttyS", 4))
 470                                 list = g_slist_append (list, g_strconcat ("/dev/", filename, NULL));
 471                 }
 472         }
 473
 474         g_dir_close (dir);
 475
 476         array = mono_array_new (mono_domain_get (), mono_get_string_class (), g_slist_length (list));
 477         for (l = list; l; l = l->next) {
 478                 mono_array_set (array, gpointer, i++, mono_string_new (mono_domain_get (), (char*)l->data));
 479                 g_free (l->data);
 480         }
 481
 482         g_slist_free (list);
 483
 484 #else
 485 #warning "list_serial_devices isn't ported to this OS"
 486 #endif
 487
 488         return array;
 489 }
 490 #endif
 491