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