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