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 "map.h"
   9 #include "mph.h"
  10
  11 #include <termios.h>
  12 #include <unistd.h>
  13 #include <fcntl.h>
  14 #include <string.h>
  15 #include <errno.h>
  16 #if defined(__APPLE__)
  17 #include "fakepoll.h"
  18 #elif defined(HAVE_POLL_H)
  19 #include <poll.h>
  20 #elif defined(HAVE_SYS_POLL_H)
  21 #include <sys/poll.h>
  22 #endif
  23 #include <sys/ioctl.h>
  24
  25 #include <glib.h>
  26
  27 /* This is for FIONREAD on solaris */
  28 #if defined(sun)
  29 #include <sys/filio.h>
  30 #endif
  31
  32 /* sys/time.h (for timeval) is required when using osx 10.3 (but not 10.4) */
  33 #ifdef __APPLE__
  34 #include <sys/time.h>
  35 #endif
  36
  37 /* This is a copy of System.IO.Ports.Handshake */
  38 typedef enum {
  39         NoneHandshake = 0,
  40         XOnXOff = 1,
  41         RequestToSend = 2,
  42         RequestToSendXOnXOff = 3
  43 } MonoHandshake;
  44
  45 /* This is a copy of System.IO.Ports.Parity */
  46 typedef enum {
  47         NoneParity = 0,
  48         Odd = 1,
  49         Even = 2,
  50         Mark = 3,
  51         Space = 4
  52 } MonoParity;
  53
  54 /* This is a copy of System.IO.Ports.StopBits */
  55 typedef enum {
  56         NoneStopBits = 0,
  57         One = 1,
  58         Two = 2,
  59         OnePointFive = 3
  60 } MonoStopBits;
  61
  62 /* This is a copy of System.IO.Ports.SerialSignal */
  63 typedef enum {
  64         NoneSignal,
  65         Cd = 1, /* Carrier detect */
  66         Cts = 2, /* Clear to send */
  67         Dsr = 4, /* Data set ready */
  68         Dtr = 8, /* Data terminal ready */
  69         Rts = 16  /* Request to send */
  70 } MonoSerialSignal;
  71
  72 /*
  73  * Silence the compiler, we do not need these prototypes to be public, since these are only
  74  * used by P/Invoke
  75  */
  76
  77 int              open_serial (char *devfile);
  78 int              close_serial (int unix_fd);
  79 guint32          read_serial (int fd, guchar *buffer, int offset, int count);
  80 int              write_serial (int fd, guchar *buffer, int offset, int count, int timeout);
  81 int              discard_buffer (int fd, gboolean input);
  82 gint32           get_bytes_in_buffer (int fd, gboolean input);
  83 gboolean         is_baud_rate_legal (int baud_rate);
  84 int              setup_baud_rate (int baud_rate);
  85 gboolean         set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake);
  86 MonoSerialSignal get_signals (int fd, gint32 *error);
  87 gint32           set_signal (int fd, MonoSerialSignal signal, gboolean value);
  88 int              breakprop (int fd);
  89 gboolean         poll_serial (int fd, gint32 *error, int timeout);
  90 void            *list_serial_devices (void);
  91
  92 int
  93 open_serial (char *devfile)
  94 {
  95         int fd;
  96         fd = open (devfile, O_RDWR | O_NOCTTY | O_NONBLOCK);
  97
  98         return fd;
  99 }
 100
 101 int
 102 close_serial (int unix_fd)
 103 {
 104         // Linus writes: do not retry close after EINTR
 105         return close (unix_fd);
 106 }
 107
 108 guint32
 109 read_serial (int fd, guchar *buffer, int offset, int count)
 110 {
 111         guint32 n;
 112
 113         n = read (fd, buffer + offset, count);
 114
 115         return (guint32) n;
 116 }
 117
 118 int
 119 write_serial (int fd, guchar *buffer, int offset, int count, int timeout)
 120 {
 121         struct pollfd pinfo;
 122         guint32 n;
 123
 124         pinfo.fd = fd;
 125         pinfo.events = POLLOUT;
 126         pinfo.revents = POLLOUT;
 127
 128         n = count;
 129
 130         while (n > 0)
 131         {
 132                 ssize_t t;
 133
 134                 if (timeout != 0) {
 135                         int c;
 136
 137                         while ((c = poll (&pinfo, 1, timeout)) == -1 && errno == EINTR)
 138                                 ;
 139                         if (c == -1)
 140                                 return -1;
 141                 }
 142
 143                 do {
 144                         t = write (fd, buffer + offset, n);
 145                 } while (t == -1 && errno == EINTR);
 146
 147                 if (t < 0)
 148                         return -1;
 149
 150                 offset += t;
 151                 n -= t;
 152         }
 153
 154         return 0;
 155 }
 156
 157 int
 158 discard_buffer (int fd, gboolean input)
 159 {
 160         return tcflush(fd, input ? TCIFLUSH : TCOFLUSH);
 161 }
 162
 163 gint32
 164 get_bytes_in_buffer (int fd, gboolean input)
 165 {
 166         gint32 retval;
 167
 168         if (ioctl (fd, input ? FIONREAD : TIOCOUTQ, &retval) == -1) {
 169                 return -1;
 170         }
 171
 172         return retval;
 173 }
 174
 175 gboolean
 176 is_baud_rate_legal (int baud_rate)
 177 {
 178         return setup_baud_rate (baud_rate) != -1;
 179 }
 180
 181 int
 182 setup_baud_rate (int baud_rate)
 183 {
 184         switch (baud_rate)
 185         {
 186 /*Some values are not defined on OSX and *BSD */
 187 #if defined(B921600)
 188         case 921600:
 189             baud_rate = B921600;
 190             break;
 191 #endif
 192 #if defined(B460800)
 193         case 460800:
 194             baud_rate = B460800;
 195             break;
 196 #endif
 197         case 230400:
 198             baud_rate = B230400;
 199             break;
 200         case 115200:
 201             baud_rate = B115200;
 202             break;
 203         case 57600:
 204             baud_rate = B57600;
 205             break;
 206         case 38400:
 207             baud_rate = B38400;
 208             break;
 209         case 19200:
 210             baud_rate = B19200;
 211             break;
 212         case 9600:
 213                 baud_rate = B9600;
 214                 break;
 215         case 4800:
 216             baud_rate = B4800;
 217                 break;
 218         case 2400:
 219             baud_rate = B2400;
 220                 break;
 221         case 1800:
 222             baud_rate = B1800;
 223                 break;
 224         case 1200:
 225             baud_rate = B1200;
 226                 break;
 227         case 600:
 228             baud_rate = B600;
 229             break;
 230         case 300:
 231             baud_rate = B300;
 232             break;
 233         case 200:
 234             baud_rate = B200;
 235             break;
 236         case 150:
 237             baud_rate = B150;
 238             break;
 239         case 134:
 240             baud_rate = B134;
 241             break;
 242         case 110:
 243             baud_rate = B110;
 244             break;
 245         case 75:
 246             baud_rate = B75;
 247             break;
 248         case 50:
 249         case 0:
 250         default:
 251             baud_rate = -1;
 252                 break;
 253         }
 254         return baud_rate;
 255 }
 256
 257 gboolean
 258 set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake)
 259 {
 260         struct termios newtio;
 261
 262         if (tcgetattr (fd, &newtio) == -1)
 263                 return FALSE;
 264
 265         newtio.c_cflag |=  (CLOCAL | CREAD);
 266         newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL | ISIG | IEXTEN );
 267         newtio.c_oflag &= ~(OPOST);
 268         newtio.c_iflag = IGNBRK;
 269
 270         /* setup baudrate */
 271         baud_rate = setup_baud_rate (baud_rate);
 272
 273         /* char lenght */
 274         newtio.c_cflag &= ~CSIZE;
 275         switch (dataBits)
 276         {
 277         case 5:
 278             newtio.c_cflag |= CS5;
 279             break;
 280         case 6:
 281             newtio.c_cflag |= CS6;
 282             break;
 283         case 7:
 284             newtio.c_cflag |= CS7;
 285             break;
 286         case 8:
 287         default:
 288                 newtio.c_cflag |= CS8;
 289                 break;
 290         }
 291
 292         /* stopbits */
 293         switch (stopBits)
 294         {
 295         case NoneStopBits:
 296                 /* Unhandled */
 297                 break;
 298         case One: /* One */
 299                 /* do nothing, the default is one stop bit */
 300             newtio.c_cflag &= ~CSTOPB;
 301                 break;
 302         case Two: /* Two */
 303                 newtio.c_cflag |= CSTOPB;
 304                 break;
 305         case OnePointFive: /* OnePointFive */
 306                 /* XXX unhandled */
 307                 break;
 308         }
 309
 310         /* parity */
 311         newtio.c_iflag &= ~(INPCK | ISTRIP );
 312
 313         switch (parity)
 314         {
 315         case NoneParity: /* None */
 316             newtio.c_cflag &= ~(PARENB | PARODD);
 317             break;
 318
 319         case Odd: /* Odd */
 320             newtio.c_cflag |= PARENB | PARODD;
 321             break;
 322
 323         case Even: /* Even */
 324             newtio.c_cflag &= ~(PARODD);
 325             newtio.c_cflag |= (PARENB);
 326             break;
 327
 328         case Mark: /* Mark */
 329             /* XXX unhandled */
 330             break;
 331         case Space: /* Space */
 332             /* XXX unhandled */
 333             break;
 334         }
 335
 336         newtio.c_iflag &= ~(IXOFF | IXON);
 337 #ifdef CRTSCTS
 338         newtio.c_cflag &= ~CRTSCTS;
 339 #endif /* def CRTSCTS */
 340
 341         switch (handshake)
 342         {
 343         case NoneHandshake: /* None */
 344                 /* do nothing */
 345                 break;
 346         case RequestToSend: /* RequestToSend (RTS) */
 347 #ifdef CRTSCTS
 348                 newtio.c_cflag |= CRTSCTS;
 349 #endif /* def CRTSCTS */
 350                 break;
 351         case RequestToSendXOnXOff: /* RequestToSendXOnXOff (RTS + XON/XOFF) */
 352 #ifdef CRTSCTS
 353                 newtio.c_cflag |= CRTSCTS;
 354 #endif /* def CRTSCTS */
 355                 /* fall through */
 356         case XOnXOff: /* XOnXOff */
 357             newtio.c_iflag |= IXOFF | IXON;
 358                 break;
 359         }
 360
 361         if (cfsetospeed (&newtio, baud_rate) < 0 || cfsetispeed (&newtio, baud_rate) < 0 ||
 362             tcsetattr (fd, TCSANOW, &newtio) < 0)
 363         {
 364                 return FALSE;
 365         }
 366         else
 367         {
 368         return TRUE;
 369         }
 370 }
 371
 372
 373 static gint32
 374 get_signal_code (MonoSerialSignal signal)
 375 {
 376         switch (signal) {
 377                 case Cd:
 378                         return TIOCM_CAR;
 379                 case Cts:
 380                         return TIOCM_CTS;
 381                 case Dsr:
 382                         return TIOCM_DSR;
 383                 case Dtr:
 384                         return TIOCM_DTR;
 385                 case Rts:
 386                         return TIOCM_RTS;
 387                 default:
 388                         return 0;
 389         }
 390
 391         /* Not reached */
 392         return 0;
 393 }
 394
 395 static MonoSerialSignal
 396 get_mono_signal_codes (int signals)
 397 {
 398         MonoSerialSignal retval = NoneSignal;
 399
 400         if ((signals & TIOCM_CAR) != 0)
 401                 retval |= Cd;
 402         if ((signals & TIOCM_CTS) != 0)
 403                 retval |= Cts;
 404         if ((signals & TIOCM_DSR) != 0)
 405                 retval |= Dsr;
 406         if ((signals & TIOCM_DTR) != 0)
 407                 retval |= Dtr;
 408         if ((signals & TIOCM_RTS) != 0)
 409                 retval |= Rts;
 410
 411         return retval;
 412 }
 413
 414 MonoSerialSignal
 415 get_signals (int fd, gint32 *error)
 416 {
 417         int signals;
 418
 419         *error = 0;
 420
 421         if (ioctl (fd, TIOCMGET, &signals) == -1) {
 422                 *error = -1;
 423                 return NoneSignal;
 424         }
 425
 426         return get_mono_signal_codes (signals);
 427 }
 428
 429 gint32
 430 set_signal (int fd, MonoSerialSignal signal, gboolean value)
 431 {
 432         int signals, expected, activated;
 433
 434         expected = get_signal_code (signal);
 435         if (ioctl (fd, TIOCMGET, &signals) == -1)
 436                 return -1;
 437
 438         activated = (signals & expected) != 0;
 439         if (activated == value) /* Already set */
 440                 return 1;
 441
 442         if (value)
 443                 signals |= expected;
 444         else
 445                 signals &= ~expected;
 446
 447         if (ioctl (fd, TIOCMSET, &signals) == -1)
 448                 return -1;
 449
 450         return 1;
 451 }
 452
 453 int
 454 breakprop (int fd)
 455 {
 456         return tcsendbreak (fd, 0);
 457 }
 458
 459 gboolean
 460 poll_serial (int fd, gint32 *error, int timeout)
 461 {
 462         struct pollfd pinfo;
 463
 464         *error = 0;
 465
 466         pinfo.fd = fd;
 467         pinfo.events = POLLIN;
 468         pinfo.revents = 0;
 469
 470         while (poll (&pinfo, 1, timeout) == -1 && errno == EINTR) {
 471                 /* EINTR is an OK condition, we should not throw in the upper layer an IOException */
 472                 if (errno != EINTR){
 473                         *error = -1;
 474                         return FALSE;
 475                 }
 476         }
 477
 478         return (pinfo.revents & POLLIN) != 0 ? 1 : 0;
 479 }
 480
 481 /*
 482  * mono internals should not be used here.
 483  * this serial stuff needs to be implemented with icalls.
 484  * make this at least compile until the code is moved elsewhere
 485  * defined(linux) is wrong, too
 486  */
 487 void*
 488 list_serial_devices (void)
 489 {
 490         return NULL;
 491 }
 492
 493 #if 0
 494 MonoArray *
 495 list_serial_devices (void)
 496 {
 497         MonoArray *array;
 498 #if defined(linux)
 499         /* Linux serial files are of the form ttyS[0-9]+ */
 500         GSList *l, *list = NULL;
 501         GDir* dir = g_dir_open ("/dev", 0, NULL);
 502         const char *filename;
 503         int i = 0;
 504
 505         while ((filename = g_dir_read_name (dir))) {
 506                 if (filename) {
 507                         if (!strncmp (filename, "ttyS", 4))
 508                                 list = g_slist_append (list, g_strconcat ("/dev/", filename, NULL));
 509                 }
 510         }
 511
 512         g_dir_close (dir);
 513
 514         array = mono_array_new (mono_domain_get (), mono_get_string_class (), g_slist_length (list));
 515         for (l = list; l; l = l->next) {
 516                 mono_array_set (array, gpointer, i++, mono_string_new (mono_domain_get (), (char*)l->data));
 517                 g_free (l->data);
 518         }
 519
 520         g_slist_free (list);
 521
 522 #else
 523 #warning "list_serial_devices isn't ported to this OS"
 524 #endif
 525
 526         return array;
 527 }
 528 #endif
 529