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(HAVE_POLL_H)
  17 #include <poll.h>
  18 #elif defined(HAVE_SYS_POLL_H)
  19 #include <sys/poll.h>
  20 #endif
  21 #include <sys/ioctl.h>
  22
  23 /* This is for ASYNC_*, serial_struct on linux */
  24 #if defined(HAVE_LINUX_SERIAL_H)
  25 #include <linux/serial.h>
  26 #endif
  27
  28 #include <glib.h>
  29
  30 /* This is for FIONREAD on solaris */
  31 #if defined(sun)
  32 #include <sys/filio.h>
  33 #endif
  34
  35 /* sys/time.h (for timeval) is required when using osx 10.3 (but not 10.4) */
  36 /* IOKit is a private framework in iOS, so exclude there */
  37 #if defined(__APPLE__) && !defined(HOST_IOS) && !defined(HOST_WATCHOS) && !defined(HOST_APPLETVOS)
  38 #define HAVE_IOKIT 1
  39 #endif
  40
  41 #if defined(HAVE_IOKIT)
  42 #include <sys/time.h>
  43 #include <IOKit/IOKitLib.h>
  44 #include <IOKit/serial/IOSerialKeys.h>
  45 #include <IOKit/serial/ioss.h>
  46 #include <IOKit/IOBSD.h>
  47 #endif
  48
  49 /* This is a copy of System.IO.Ports.Handshake */
  50 typedef enum {
  51         NoneHandshake = 0,
  52         XOnXOff = 1,
  53         RequestToSend = 2,
  54         RequestToSendXOnXOff = 3
  55 } MonoHandshake;
  56
  57 /* This is a copy of System.IO.Ports.Parity */
  58 typedef enum {
  59         NoneParity = 0,
  60         Odd = 1,
  61         Even = 2,
  62         Mark = 3,
  63         Space = 4
  64 } MonoParity;
  65
  66 /* This is a copy of System.IO.Ports.StopBits */
  67 typedef enum {
  68         NoneStopBits = 0,
  69         One = 1,
  70         Two = 2,
  71         OnePointFive = 3
  72 } MonoStopBits;
  73
  74 /* This is a copy of System.IO.Ports.SerialSignal */
  75 typedef enum {
  76         NoneSignal,
  77         Cd = 1, /* Carrier detect */
  78         Cts = 2, /* Clear to send */
  79         Dsr = 4, /* Data set ready */
  80         Dtr = 8, /* Data terminal ready */
  81         Rts = 16  /* Request to send */
  82 } MonoSerialSignal;
  83
  84 /*
  85  * Silence the compiler, we do not need these prototypes to be public, since these are only
  86  * used by P/Invoke
  87  */
  88
  89 int              open_serial (char *devfile);
  90 int              close_serial (int unix_fd);
  91 guint32          read_serial (int fd, guchar *buffer, int offset, int count);
  92 int              write_serial (int fd, guchar *buffer, int offset, int count, int timeout);
  93 int              discard_buffer (int fd, gboolean input);
  94 gint32           get_bytes_in_buffer (int fd, gboolean input);
  95 gboolean         is_baud_rate_legal (int baud_rate);
  96 int              setup_baud_rate (int baud_rate, gboolean *custom_baud_rate);
  97 gboolean         set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake);
  98 MonoSerialSignal get_signals (int fd, gint32 *error);
  99 gint32           set_signal (int fd, MonoSerialSignal signal, gboolean value);
 100 int              breakprop (int fd);
 101 gboolean         poll_serial (int fd, gint32 *error, int timeout);
 102 void            *list_serial_devices (void);
 103
 104 int
 105 open_serial (char *devfile)
 106 {
 107         int fd;
 108         fd = open (devfile, O_RDWR | O_NOCTTY | O_NONBLOCK);
 109
 110         return fd;
 111 }
 112
 113 int
 114 close_serial (int unix_fd)
 115 {
 116         // Linus writes: do not retry close after EINTR
 117         return close (unix_fd);
 118 }
 119
 120 guint32
 121 read_serial (int fd, guchar *buffer, int offset, int count)
 122 {
 123         guint32 n;
 124
 125         n = read (fd, buffer + offset, count);
 126
 127         return (guint32) n;
 128 }
 129
 130 int
 131 write_serial (int fd, guchar *buffer, int offset, int count, int timeout)
 132 {
 133         struct pollfd pinfo;
 134         guint32 n;
 135
 136         pinfo.fd = fd;
 137         pinfo.events = POLLOUT;
 138         pinfo.revents = POLLOUT;
 139
 140         n = count;
 141
 142         while (n > 0)
 143         {
 144                 ssize_t t;
 145
 146                 if (timeout != 0) {
 147                         int c;
 148
 149                         while ((c = poll (&pinfo, 1, timeout)) == -1 && errno == EINTR)
 150                                 ;
 151                         if (c == -1)
 152                                 return -1;
 153                 }
 154
 155                 do {
 156                         t = write (fd, buffer + offset, n);
 157                 } while (t == -1 && errno == EINTR);
 158
 159                 if (t < 0)
 160                         return -1;
 161
 162                 offset += t;
 163                 n -= t;
 164         }
 165
 166         return 0;
 167 }
 168
 169 int
 170 discard_buffer (int fd, gboolean input)
 171 {
 172         return tcflush(fd, input ? TCIFLUSH : TCOFLUSH);
 173 }
 174
 175 gint32
 176 get_bytes_in_buffer (int fd, gboolean input)
 177 {
 178 #if defined(__HAIKU__)
 179         /* FIXME: Haiku doesn't support TIOCOUTQ nor FIONREAD on fds */
 180         return -1;
 181 #define TIOCOUTQ 0
 182 #endif
 183         gint32 retval;
 184
 185         if (ioctl (fd, input ? FIONREAD : TIOCOUTQ, &retval) == -1) {
 186                 return -1;
 187         }
 188
 189         return retval;
 190 }
 191
 192 gboolean
 193 is_baud_rate_legal (int baud_rate)
 194 {
 195         gboolean ignore = FALSE;
 196         return setup_baud_rate (baud_rate, &ignore) != -1;
 197 }
 198
 199 int
 200 setup_baud_rate (int baud_rate, gboolean *custom_baud_rate)
 201 {
 202         switch (baud_rate)
 203         {
 204 /*Some values are not defined on OSX and *BSD */
 205 #if defined(B921600)
 206         case 921600:
 207             baud_rate = B921600;
 208             break;
 209 #endif
 210 #if defined(B460800)
 211         case 460800:
 212             baud_rate = B460800;
 213             break;
 214 #endif
 215         case 230400:
 216             baud_rate = B230400;
 217             break;
 218         case 115200:
 219             baud_rate = B115200;
 220             break;
 221         case 57600:
 222             baud_rate = B57600;
 223             break;
 224         case 38400:
 225             baud_rate = B38400;
 226             break;
 227         case 19200:
 228             baud_rate = B19200;
 229             break;
 230         case 9600:
 231                 baud_rate = B9600;
 232                 break;
 233         case 4800:
 234             baud_rate = B4800;
 235                 break;
 236         case 2400:
 237             baud_rate = B2400;
 238                 break;
 239         case 1800:
 240             baud_rate = B1800;
 241                 break;
 242         case 1200:
 243             baud_rate = B1200;
 244                 break;
 245         case 600:
 246             baud_rate = B600;
 247             break;
 248         case 300:
 249             baud_rate = B300;
 250             break;
 251         case 200:
 252             baud_rate = B200;
 253             break;
 254         case 150:
 255             baud_rate = B150;
 256             break;
 257         case 134:
 258             baud_rate = B134;
 259             break;
 260         case 110:
 261             baud_rate = B110;
 262             break;
 263         case 75:
 264             baud_rate = B75;
 265             break;
 266         case 50:
 267 #ifdef B50
 268             baud_rate = B50;
 269 #else
 270             baud_rate = -1;
 271             break;
 272 #endif
 273         case 0:
 274 #ifdef B0
 275             baud_rate = B0;
 276 #else
 277             baud_rate = -1;
 278 #endif
 279             break;
 280         default:
 281                 *custom_baud_rate = TRUE;
 282                 break;
 283         }
 284         return baud_rate;
 285 }
 286
 287 gboolean
 288 set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake)
 289 {
 290         struct termios newtio;
 291         gboolean custom_baud_rate = FALSE;
 292
 293         if (tcgetattr (fd, &newtio) == -1)
 294                 return FALSE;
 295
 296         newtio.c_cflag |=  (CLOCAL | CREAD);
 297         newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL | ISIG | IEXTEN );
 298         newtio.c_oflag &= ~(OPOST);
 299         newtio.c_iflag = IGNBRK;
 300
 301         /* setup baudrate */
 302         baud_rate = setup_baud_rate (baud_rate, &custom_baud_rate);
 303
 304         /* char lenght */
 305         newtio.c_cflag &= ~CSIZE;
 306         switch (dataBits)
 307         {
 308         case 5:
 309             newtio.c_cflag |= CS5;
 310             break;
 311         case 6:
 312             newtio.c_cflag |= CS6;
 313             break;
 314         case 7:
 315             newtio.c_cflag |= CS7;
 316             break;
 317         case 8:
 318         default:
 319                 newtio.c_cflag |= CS8;
 320                 break;
 321         }
 322
 323         /* stopbits */
 324         switch (stopBits)
 325         {
 326         case NoneStopBits:
 327                 /* Unhandled */
 328                 break;
 329         case One: /* One */
 330                 /* do nothing, the default is one stop bit */
 331             newtio.c_cflag &= ~CSTOPB;
 332                 break;
 333         case Two: /* Two */
 334                 newtio.c_cflag |= CSTOPB;
 335                 break;
 336         case OnePointFive: /* OnePointFive */
 337                 /* XXX unhandled */
 338                 break;
 339         }
 340
 341         /* parity */
 342         newtio.c_iflag &= ~(INPCK | ISTRIP );
 343
 344         switch (parity)
 345         {
 346         case NoneParity: /* None */
 347             newtio.c_cflag &= ~(PARENB | PARODD);
 348             break;
 349
 350         case Odd: /* Odd */
 351             newtio.c_cflag |= PARENB | PARODD;
 352             break;
 353
 354         case Even: /* Even */
 355             newtio.c_cflag &= ~(PARODD);
 356             newtio.c_cflag |= (PARENB);
 357             break;
 358
 359         case Mark: /* Mark */
 360             /* XXX unhandled */
 361             break;
 362         case Space: /* Space */
 363             /* XXX unhandled */
 364             break;
 365         }
 366
 367         newtio.c_iflag &= ~(IXOFF | IXON);
 368 #ifdef CRTSCTS
 369         newtio.c_cflag &= ~CRTSCTS;
 370 #endif /* def CRTSCTS */
 371
 372         switch (handshake)
 373         {
 374         case NoneHandshake: /* None */
 375                 /* do nothing */
 376                 break;
 377         case RequestToSend: /* RequestToSend (RTS) */
 378 #ifdef CRTSCTS
 379                 newtio.c_cflag |= CRTSCTS;
 380 #endif /* def CRTSCTS */
 381                 break;
 382         case RequestToSendXOnXOff: /* RequestToSendXOnXOff (RTS + XON/XOFF) */
 383 #ifdef CRTSCTS
 384                 newtio.c_cflag |= CRTSCTS;
 385 #endif /* def CRTSCTS */
 386                 /* fall through */
 387         case XOnXOff: /* XOnXOff */
 388             newtio.c_iflag |= IXOFF | IXON;
 389                 break;
 390         }
 391
 392         if (custom_baud_rate == FALSE) {
 393                 if (cfsetospeed (&newtio, baud_rate) < 0 || cfsetispeed (&newtio, baud_rate) < 0)
 394                         return FALSE;
 395         } else {
 396 #if __linux__ || defined(HAVE_IOKIT)
 397
 398                 /* On Linux to set a custom baud rate, we must set the
 399                  * "standard" baud_rate to 38400.   On Apple we set it purely
 400                  * so that tcsetattr has something to use (and report back later), but
 401                  * the Apple specific API is still opaque to these APIs, see:
 402                  * https://developer.apple.com/library/mac/samplecode/SerialPortSample/Listings/SerialPortSample_SerialPortSample_c.html#//apple_ref/doc/uid/DTS10000454-SerialPortSample_SerialPortSample_c-DontLinkElementID_4
 403                  */
 404                 if (cfsetospeed (&newtio, B38400) < 0 || cfsetispeed (&newtio, B38400) < 0)
 405                         return FALSE;
 406 #endif
 407         }
 408
 409         if (tcsetattr (fd, TCSANOW, &newtio) < 0)
 410                 return FALSE;
 411
 412         if (custom_baud_rate == TRUE){
 413 #if defined(HAVE_LINUX_SERIAL_H)
 414                 struct serial_struct ser;
 415
 416                 if (ioctl (fd, TIOCGSERIAL, &ser) < 0)
 417                 {
 418                         return FALSE;
 419                 }
 420
 421                 ser.custom_divisor = ser.baud_base / baud_rate;
 422                 ser.flags &= ~ASYNC_SPD_MASK;
 423                 ser.flags |= ASYNC_SPD_CUST;
 424
 425                 if (ioctl (fd, TIOCSSERIAL, &ser) < 0)
 426                 {
 427                         return FALSE;
 428                 }
 429 #elif defined(HAVE_IOKIT)
 430                 speed_t speed = baud_rate;
 431                 if (ioctl(fd, IOSSIOSPEED, &speed) == -1)
 432                         return FALSE;
 433 #else
 434                 /* Don't know how to set custom baud rate on this platform. */
 435                 return FALSE;
 436 #endif
 437         }
 438
 439         return TRUE;
 440 }
 441
 442
 443 static gint32
 444 get_signal_code (MonoSerialSignal signal)
 445 {
 446         switch (signal) {
 447                 case Cd:
 448                         return TIOCM_CAR;
 449                 case Cts:
 450                         return TIOCM_CTS;
 451                 case Dsr:
 452                         return TIOCM_DSR;
 453                 case Dtr:
 454                         return TIOCM_DTR;
 455                 case Rts:
 456                         return TIOCM_RTS;
 457                 default:
 458                         return 0;
 459         }
 460
 461         /* Not reached */
 462         return 0;
 463 }
 464
 465 static MonoSerialSignal
 466 get_mono_signal_codes (int signals)
 467 {
 468         MonoSerialSignal retval = NoneSignal;
 469
 470         if ((signals & TIOCM_CAR) != 0)
 471                 retval |= Cd;
 472         if ((signals & TIOCM_CTS) != 0)
 473                 retval |= Cts;
 474         if ((signals & TIOCM_DSR) != 0)
 475                 retval |= Dsr;
 476         if ((signals & TIOCM_DTR) != 0)
 477                 retval |= Dtr;
 478         if ((signals & TIOCM_RTS) != 0)
 479                 retval |= Rts;
 480
 481         return retval;
 482 }
 483
 484 MonoSerialSignal
 485 get_signals (int fd, gint32 *error)
 486 {
 487         int signals;
 488
 489         *error = 0;
 490
 491         if (ioctl (fd, TIOCMGET, &signals) == -1) {
 492                 *error = -1;
 493                 return NoneSignal;
 494         }
 495
 496         return get_mono_signal_codes (signals);
 497 }
 498
 499 gint32
 500 set_signal (int fd, MonoSerialSignal signal, gboolean value)
 501 {
 502         int signals, expected, activated;
 503
 504         expected = get_signal_code (signal);
 505         if (ioctl (fd, TIOCMGET, &signals) == -1)
 506                 return -1;
 507
 508         activated = (signals & expected) != 0;
 509         if (activated == value) /* Already set */
 510                 return 1;
 511
 512         if (value)
 513                 signals |= expected;
 514         else
 515                 signals &= ~expected;
 516
 517         if (ioctl (fd, TIOCMSET, &signals) == -1)
 518                 return -1;
 519
 520         return 1;
 521 }
 522
 523 int
 524 breakprop (int fd)
 525 {
 526         return tcsendbreak (fd, 0);
 527 }
 528
 529 gboolean
 530 poll_serial (int fd, gint32 *error, int timeout)
 531 {
 532         struct pollfd pinfo;
 533
 534         *error = 0;
 535
 536         pinfo.fd = fd;
 537         pinfo.events = POLLIN;
 538         pinfo.revents = 0;
 539
 540         while (poll (&pinfo, 1, timeout) == -1 && errno == EINTR) {
 541                 /* EINTR is an OK condition, we should not throw in the upper layer an IOException */
 542                 if (errno != EINTR){
 543                         *error = -1;
 544                         return FALSE;
 545                 }
 546         }
 547
 548         return (pinfo.revents & POLLIN) != 0 ? 1 : 0;
 549 }
 550
 551 /*
 552  * mono internals should not be used here.
 553  * this serial stuff needs to be implemented with icalls.
 554  * make this at least compile until the code is moved elsewhere
 555  * defined(linux) is wrong, too
 556  */
 557 void*
 558 list_serial_devices (void)
 559 {
 560         return NULL;
 561 }
 562
 563 #if 0
 564 MonoArray *
 565 list_serial_devices (void)
 566 {
 567         MonoArray *array;
 568 #if defined(linux)
 569         /* Linux serial files are of the form ttyS[0-9]+ */
 570         GSList *l, *list = NULL;
 571         GDir* dir = g_dir_open ("/dev", 0, NULL);
 572         const char *filename;
 573         int i = 0;
 574
 575         while ((filename = g_dir_read_name (dir))) {
 576                 if (filename) {
 577                         if (!strncmp (filename, "ttyS", 4))
 578                                 list = g_slist_append (list, g_strconcat ("/dev/", filename, NULL));
 579                 }
 580         }
 581
 582         g_dir_close (dir);
 583
 584         array = mono_array_new (mono_domain_get (), mono_get_string_class (), g_slist_length (list));
 585         for (l = list; l; l = l->next) {
 586                 mono_array_set (array, gpointer, i++, mono_string_new (mono_domain_get (), (char*)l->data));
 587                 g_free (l->data);
 588         }
 589
 590         g_slist_free (list);
 591
 592 #else
 593 #warning "list_serial_devices isn't ported to this OS"
 594 #endif
 595
 596         return array;
 597 }
 598 #endif
 599