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 is_baud_rate_legal (int baud_rate)
 152 {
 153         return setup_baud_rate (baud_rate) != -1;
 154 }
 155
 156 int
 157 setup_baud_rate (int baud_rate)
 158 {
 159         switch (baud_rate)
 160         {
 161 /*Some values are not defined on OSX and *BSD */
 162 #if defined(B921600)
 163         case 921600:
 164             baud_rate = B921600;
 165             break;
 166 #endif
 167 #if defined(B460800)
 168         case 460800:
 169             baud_rate = B460800;
 170             break;
 171 #endif
 172         case 230400:
 173             baud_rate = B230400;
 174             break;
 175         case 115200:
 176             baud_rate = B115200;
 177             break;
 178         case 57600:
 179             baud_rate = B57600;
 180             break;
 181         case 38400:
 182             baud_rate = B38400;
 183             break;
 184         case 19200:
 185             baud_rate = B19200;
 186             break;
 187         case 9600:
 188                 baud_rate = B9600;
 189                 break;
 190         case 4800:
 191             baud_rate = B4800;
 192                 break;
 193         case 2400:
 194             baud_rate = B2400;
 195                 break;
 196         case 1800:
 197             baud_rate = B1800;
 198                 break;
 199         case 1200:
 200             baud_rate = B1200;
 201                 break;
 202         case 600:
 203             baud_rate = B600;
 204             break;
 205         case 300:
 206             baud_rate = B300;
 207             break;
 208         case 200:
 209             baud_rate = B200;
 210             break;
 211         case 150:
 212             baud_rate = B150;
 213             break;
 214         case 134:
 215             baud_rate = B134;
 216             break;
 217         case 110:
 218             baud_rate = B110;
 219             break;
 220         case 75:
 221             baud_rate = B75;
 222             break;
 223         case 50:
 224         case 0:
 225         default:
 226             baud_rate = -1;
 227                 break;
 228         }
 229         return baud_rate;
 230 }
 231
 232 gboolean
 233 set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake)
 234 {
 235         struct termios newtio;
 236
 237         if (tcgetattr (fd, &newtio) == -1)
 238                 return FALSE;
 239
 240         newtio.c_cflag |=  (CLOCAL | CREAD);
 241         newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL | ISIG | IEXTEN );
 242         newtio.c_oflag &= ~(OPOST);
 243         newtio.c_iflag = IGNBRK;
 244
 245         /* setup baudrate */
 246         baud_rate = setup_baud_rate (baud_rate);
 247
 248         /* char lenght */
 249         newtio.c_cflag &= ~CSIZE;
 250         switch (dataBits)
 251         {
 252         case 5:
 253             newtio.c_cflag |= CS5;
 254             break;
 255         case 6:
 256             newtio.c_cflag |= CS6;
 257             break;
 258         case 7:
 259             newtio.c_cflag |= CS7;
 260             break;
 261         case 8:
 262         default:
 263                 newtio.c_cflag |= CS8;
 264                 break;
 265         }
 266
 267         /* stopbits */
 268         switch (stopBits)
 269         {
 270         case NoneStopBits:
 271                 /* Unhandled */
 272                 break;
 273         case One: /* One */
 274                 /* do nothing, the default is one stop bit */
 275             newtio.c_cflag &= ~CSTOPB;
 276                 break;
 277         case Two: /* Two */
 278                 newtio.c_cflag |= CSTOPB;
 279                 break;
 280         case OnePointFive: /* OnePointFive */
 281                 /* XXX unhandled */
 282                 break;
 283         }
 284
 285         /* parity */
 286         newtio.c_iflag &= ~(INPCK | ISTRIP );
 287
 288         switch (parity)
 289         {
 290         case NoneParity: /* None */
 291             newtio.c_cflag &= ~(PARENB | PARODD);
 292             break;
 293
 294         case Odd: /* Odd */
 295             newtio.c_cflag |= PARENB | PARODD;
 296             break;
 297
 298         case Even: /* Even */
 299             newtio.c_cflag &= ~(PARODD);
 300             newtio.c_cflag |= (PARENB);
 301             break;
 302
 303         case Mark: /* Mark */
 304             /* XXX unhandled */
 305             break;
 306         case Space: /* Space */
 307             /* XXX unhandled */
 308             break;
 309         }
 310
 311         newtio.c_iflag &= ~(IXOFF | IXON);
 312 #ifdef CRTSCTS
 313         newtio.c_cflag &= ~CRTSCTS;
 314 #endif /* def CRTSCTS */
 315
 316         switch (handshake)
 317         {
 318         case NoneHandshake: /* None */
 319                 /* do nothing */
 320                 break;
 321         case RequestToSend: /* RequestToSend (RTS) */
 322 #ifdef CRTSCTS
 323                 newtio.c_cflag |= CRTSCTS;
 324 #endif /* def CRTSCTS */
 325                 break;
 326         case RequestToSendXOnXOff: /* RequestToSendXOnXOff (RTS + XON/XOFF) */
 327 #ifdef CRTSCTS
 328                 newtio.c_cflag |= CRTSCTS;
 329 #endif /* def CRTSCTS */
 330                 /* fall through */
 331         case XOnXOff: /* XOnXOff */
 332             newtio.c_iflag |= IXOFF | IXON;
 333                 break;
 334         }
 335
 336         if (cfsetospeed (&newtio, baud_rate) < 0 || cfsetispeed (&newtio, baud_rate) < 0 ||
 337             tcsetattr (fd, TCSANOW, &newtio) < 0)
 338         {
 339                 return FALSE;
 340         }
 341         else
 342         {
 343         return TRUE;
 344         }
 345 }
 346
 347
 348 static gint32
 349 get_signal_code (MonoSerialSignal signal)
 350 {
 351         switch (signal) {
 352                 case Cd:
 353                         return TIOCM_CAR;
 354                 case Cts:
 355                         return TIOCM_CTS;
 356                 case Dsr:
 357                         return TIOCM_DSR;
 358                 case Dtr:
 359                         return TIOCM_DTR;
 360                 case Rts:
 361                         return TIOCM_RTS;
 362                 default:
 363                         return 0;
 364         }
 365
 366         /* Not reached */
 367         return 0;
 368 }
 369
 370 static MonoSerialSignal
 371 get_mono_signal_codes (int signals)
 372 {
 373         MonoSerialSignal retval = NoneSignal;
 374
 375         if ((signals & TIOCM_CAR) != 0)
 376                 retval |= Cd;
 377         if ((signals & TIOCM_CTS) != 0)
 378                 retval |= Cts;
 379         if ((signals & TIOCM_DSR) != 0)
 380                 retval |= Dsr;
 381         if ((signals & TIOCM_DTR) != 0)
 382                 retval |= Dtr;
 383         if ((signals & TIOCM_RTS) != 0)
 384                 retval |= Rts;
 385
 386         return retval;
 387 }
 388
 389 MonoSerialSignal
 390 get_signals (int fd, gint32 *error)
 391 {
 392         int signals;
 393
 394         *error = 0;
 395
 396         if (ioctl (fd, TIOCMGET, &signals) == -1) {
 397                 *error = -1;
 398                 return NoneSignal;
 399         }
 400
 401         return get_mono_signal_codes (signals);
 402 }
 403
 404 gint32
 405 set_signal (int fd, MonoSerialSignal signal, gboolean value)
 406 {
 407         int signals, expected, activated;
 408
 409         expected = get_signal_code (signal);
 410         if (ioctl (fd, TIOCMGET, &signals) == -1)
 411                 return -1;
 412
 413         activated = (signals & expected) != 0;
 414         if (activated == value) /* Already set */
 415                 return 1;
 416
 417         if (value)
 418                 signals |= expected;
 419         else
 420                 signals &= ~expected;
 421
 422         if (ioctl (fd, TIOCMSET, &signals) == -1)
 423                 return -1;
 424
 425         return 1;
 426 }
 427
 428 int
 429 breakprop (int fd)
 430 {
 431         return tcsendbreak (fd, 0);
 432 }
 433
 434 gboolean
 435 poll_serial (int fd, gint32 *error, int timeout)
 436 {
 437         struct pollfd pinfo;
 438
 439         *error = 0;
 440
 441         pinfo.fd = fd;
 442         pinfo.events = POLLIN;
 443         pinfo.revents = 0;
 444
 445         while (poll (&pinfo, 1, timeout) == -1 && errno == EINTR) {
 446                 /* EINTR is an OK condition, we should not throw in the upper layer an IOException */
 447                 if (errno != EINTR){
 448                         *error = -1;
 449                         return FALSE;
 450                 }
 451         }
 452
 453         return (pinfo.revents & POLLIN) != 0 ? 1 : 0;
 454 }
 455
 456 /*
 457  * mono internals should not be used here.
 458  * this serial stuff needs to be implemented with icalls.
 459  * make this at least compile until the code is moved elsewhere
 460  * defined(linux) is wrong, too
 461  */
 462 void*
 463 list_serial_devices (void)
 464 {
 465         return NULL;
 466 }
 467
 468 #if 0
 469 MonoArray *
 470 list_serial_devices (void)
 471 {
 472         MonoArray *array;
 473 #if defined(linux)
 474         /* Linux serial files are of the form ttyS[0-9]+ */
 475         GSList *l, *list = NULL;
 476         GDir* dir = g_dir_open ("/dev", 0, NULL);
 477         const char *filename;
 478         int i = 0;
 479
 480         while ((filename = g_dir_read_name (dir))) {
 481                 if (filename) {
 482                         if (!strncmp (filename, "ttyS", 4))
 483                                 list = g_slist_append (list, g_strconcat ("/dev/", filename, NULL));
 484                 }
 485         }
 486
 487         g_dir_close (dir);
 488
 489         array = mono_array_new (mono_domain_get (), mono_get_string_class (), g_slist_length (list));
 490         for (l = list; l; l = l->next) {
 491                 mono_array_set (array, gpointer, i++, mono_string_new (mono_domain_get (), (char*)l->data));
 492                 g_free (l->data);
 493         }
 494
 495         g_slist_free (list);
 496
 497 #else
 498 #warning "list_serial_devices isn't ported to this OS"
 499 #endif
 500
 501         return array;
 502 }
 503 #endif
 504