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_TVOS)
  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, *BSD, or AIX */
 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 #if defined(B230400)
 216         case 230400:
 217             baud_rate = B230400;
 218             break;
 219 #endif
 220 #if defined(B115200)
 221         case 115200:
 222             baud_rate = B115200;
 223             break;
 224 #endif
 225 #if defined(B57600)
 226         case 57600:
 227             baud_rate = B57600;
 228             break;
 229 #endif
 230         case 38400:
 231             baud_rate = B38400;
 232             break;
 233         case 19200:
 234             baud_rate = B19200;
 235             break;
 236         case 9600:
 237                 baud_rate = B9600;
 238                 break;
 239         case 4800:
 240             baud_rate = B4800;
 241                 break;
 242         case 2400:
 243             baud_rate = B2400;
 244                 break;
 245         case 1800:
 246             baud_rate = B1800;
 247                 break;
 248         case 1200:
 249             baud_rate = B1200;
 250                 break;
 251         case 600:
 252             baud_rate = B600;
 253             break;
 254         case 300:
 255             baud_rate = B300;
 256             break;
 257         case 200:
 258             baud_rate = B200;
 259             break;
 260         case 150:
 261             baud_rate = B150;
 262             break;
 263         case 134:
 264             baud_rate = B134;
 265             break;
 266         case 110:
 267             baud_rate = B110;
 268             break;
 269         case 75:
 270             baud_rate = B75;
 271             break;
 272         case 50:
 273 #ifdef B50
 274             baud_rate = B50;
 275 #else
 276             baud_rate = -1;
 277             break;
 278 #endif
 279         case 0:
 280 #ifdef B0
 281             baud_rate = B0;
 282 #else
 283             baud_rate = -1;
 284 #endif
 285             break;
 286         default:
 287                 *custom_baud_rate = TRUE;
 288                 break;
 289         }
 290         return baud_rate;
 291 }
 292
 293 gboolean
 294 set_attributes (int fd, int baud_rate, MonoParity parity, int dataBits, MonoStopBits stopBits, MonoHandshake handshake)
 295 {
 296         struct termios newtio;
 297         gboolean custom_baud_rate = FALSE;
 298
 299         if (tcgetattr (fd, &newtio) == -1)
 300                 return FALSE;
 301
 302         newtio.c_cflag |=  (CLOCAL | CREAD);
 303         newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL | ISIG | IEXTEN );
 304         newtio.c_oflag &= ~(OPOST);
 305         newtio.c_iflag = IGNBRK;
 306
 307         /* setup baudrate */
 308         baud_rate = setup_baud_rate (baud_rate, &custom_baud_rate);
 309
 310         /* char lenght */
 311         newtio.c_cflag &= ~CSIZE;
 312         switch (dataBits)
 313         {
 314         case 5:
 315             newtio.c_cflag |= CS5;
 316             break;
 317         case 6:
 318             newtio.c_cflag |= CS6;
 319             break;
 320         case 7:
 321             newtio.c_cflag |= CS7;
 322             break;
 323         case 8:
 324         default:
 325                 newtio.c_cflag |= CS8;
 326                 break;
 327         }
 328
 329         /* stopbits */
 330         switch (stopBits)
 331         {
 332         case NoneStopBits:
 333                 /* Unhandled */
 334                 break;
 335         case One: /* One */
 336                 /* do nothing, the default is one stop bit */
 337             newtio.c_cflag &= ~CSTOPB;
 338                 break;
 339         case Two: /* Two */
 340                 newtio.c_cflag |= CSTOPB;
 341                 break;
 342         case OnePointFive: /* OnePointFive */
 343                 /* 8250 UART handles stop bit flag as 1.5 stop bits for 5 data bits */
 344                 newtio.c_cflag |= CSTOPB;
 345                 break;
 346         }
 347
 348         /* parity */
 349         newtio.c_iflag &= ~(INPCK | ISTRIP );
 350
 351         switch (parity)
 352         {
 353         case NoneParity: /* None */
 354             newtio.c_cflag &= ~(PARENB | PARODD);
 355             break;
 356
 357         case Odd: /* Odd */
 358             newtio.c_cflag |= PARENB | PARODD;
 359             break;
 360
 361         case Even: /* Even */
 362             newtio.c_cflag &= ~(PARODD);
 363             newtio.c_cflag |= (PARENB);
 364             break;
 365
 366         case Mark: /* Mark */
 367             /* XXX unhandled */
 368             break;
 369         case Space: /* Space */
 370             /* XXX unhandled */
 371             break;
 372         }
 373
 374         newtio.c_iflag &= ~(IXOFF | IXON);
 375 #ifdef CRTSCTS
 376         newtio.c_cflag &= ~CRTSCTS;
 377 #endif /* def CRTSCTS */
 378
 379         switch (handshake)
 380         {
 381         case NoneHandshake: /* None */
 382                 /* do nothing */
 383                 break;
 384         case RequestToSend: /* RequestToSend (RTS) */
 385 #ifdef CRTSCTS
 386                 newtio.c_cflag |= CRTSCTS;
 387 #endif /* def CRTSCTS */
 388                 break;
 389         case RequestToSendXOnXOff: /* RequestToSendXOnXOff (RTS + XON/XOFF) */
 390 #ifdef CRTSCTS
 391                 newtio.c_cflag |= CRTSCTS;
 392 #endif /* def CRTSCTS */
 393                 /* fall through */
 394         case XOnXOff: /* XOnXOff */
 395             newtio.c_iflag |= IXOFF | IXON;
 396                 break;
 397         }
 398
 399         if (custom_baud_rate == FALSE) {
 400                 if (cfsetospeed (&newtio, baud_rate) < 0 || cfsetispeed (&newtio, baud_rate) < 0)
 401                         return FALSE;
 402         } else {
 403 #if __linux__ || defined(HAVE_IOKIT)
 404
 405                 /* On Linux to set a custom baud rate, we must set the
 406                  * "standard" baud_rate to 38400.   On Apple we set it purely
 407                  * so that tcsetattr has something to use (and report back later), but
 408                  * the Apple specific API is still opaque to these APIs, see:
 409                  * https://developer.apple.com/library/mac/samplecode/SerialPortSample/Listings/SerialPortSample_SerialPortSample_c.html#//apple_ref/doc/uid/DTS10000454-SerialPortSample_SerialPortSample_c-DontLinkElementID_4
 410                  */
 411                 if (cfsetospeed (&newtio, B38400) < 0 || cfsetispeed (&newtio, B38400) < 0)
 412                         return FALSE;
 413 #endif
 414         }
 415
 416         if (tcsetattr (fd, TCSANOW, &newtio) < 0)
 417                 return FALSE;
 418
 419         if (custom_baud_rate == TRUE){
 420 #if defined(HAVE_LINUX_SERIAL_H)
 421                 struct serial_struct ser;
 422
 423                 if (ioctl (fd, TIOCGSERIAL, &ser) < 0)
 424                 {
 425                         return FALSE;
 426                 }
 427
 428                 ser.custom_divisor = ser.baud_base / baud_rate;
 429                 ser.flags &= ~ASYNC_SPD_MASK;
 430                 ser.flags |= ASYNC_SPD_CUST;
 431
 432                 if (ioctl (fd, TIOCSSERIAL, &ser) < 0)
 433                 {
 434                         return FALSE;
 435                 }
 436 #elif defined(HAVE_IOKIT)
 437                 speed_t speed = baud_rate;
 438                 if (ioctl(fd, IOSSIOSPEED, &speed) == -1)
 439                         return FALSE;
 440 #else
 441                 /* Don't know how to set custom baud rate on this platform. */
 442                 return FALSE;
 443 #endif
 444         }
 445
 446         return TRUE;
 447 }
 448
 449
 450 static gint32
 451 get_signal_code (MonoSerialSignal signal)
 452 {
 453         switch (signal) {
 454                 case Cd:
 455                         return TIOCM_CAR;
 456                 case Cts:
 457                         return TIOCM_CTS;
 458                 case Dsr:
 459                         return TIOCM_DSR;
 460                 case Dtr:
 461                         return TIOCM_DTR;
 462                 case Rts:
 463                         return TIOCM_RTS;
 464                 default:
 465                         return 0;
 466         }
 467
 468         /* Not reached */
 469         return 0;
 470 }
 471
 472 static MonoSerialSignal
 473 get_mono_signal_codes (int signals)
 474 {
 475         MonoSerialSignal retval = NoneSignal;
 476
 477         if ((signals & TIOCM_CAR) != 0)
 478                 retval |= Cd;
 479         if ((signals & TIOCM_CTS) != 0)
 480                 retval |= Cts;
 481         if ((signals & TIOCM_DSR) != 0)
 482                 retval |= Dsr;
 483         if ((signals & TIOCM_DTR) != 0)
 484                 retval |= Dtr;
 485         if ((signals & TIOCM_RTS) != 0)
 486                 retval |= Rts;
 487
 488         return retval;
 489 }
 490
 491 MonoSerialSignal
 492 get_signals (int fd, gint32 *error)
 493 {
 494         int signals;
 495
 496         *error = 0;
 497
 498         if (ioctl (fd, TIOCMGET, &signals) == -1) {
 499                 *error = -1;
 500                 return NoneSignal;
 501         }
 502
 503         return get_mono_signal_codes (signals);
 504 }
 505
 506 gint32
 507 set_signal (int fd, MonoSerialSignal signal, gboolean value)
 508 {
 509         int signals, expected, activated;
 510
 511         expected = get_signal_code (signal);
 512         if (ioctl (fd, TIOCMGET, &signals) == -1)
 513                 return -1;
 514
 515         activated = (signals & expected) != 0;
 516         if (activated == value) /* Already set */
 517                 return 1;
 518
 519         if (value)
 520                 signals |= expected;
 521         else
 522                 signals &= ~expected;
 523
 524         if (ioctl (fd, TIOCMSET, &signals) == -1)
 525                 return -1;
 526
 527         return 1;
 528 }
 529
 530 int
 531 breakprop (int fd)
 532 {
 533         return tcsendbreak (fd, 0);
 534 }
 535
 536 gboolean
 537 poll_serial (int fd, gint32 *error, int timeout)
 538 {
 539         struct pollfd pinfo;
 540
 541         *error = 0;
 542
 543         pinfo.fd = fd;
 544         pinfo.events = POLLIN;
 545         pinfo.revents = 0;
 546
 547         while (poll (&pinfo, 1, timeout) == -1 && errno == EINTR) {
 548                 /* EINTR is an OK condition, we should not throw in the upper layer an IOException */
 549                 if (errno != EINTR){
 550                         *error = -1;
 551                         return FALSE;
 552                 }
 553         }
 554
 555         return (pinfo.revents & POLLIN) != 0 ? 1 : 0;
 556 }
 557
 558 /*
 559  * mono internals should not be used here.
 560  * this serial stuff needs to be implemented with icalls.
 561  * make this at least compile until the code is moved elsewhere
 562  * defined(linux) is wrong, too
 563  */
 564 void*
 565 list_serial_devices (void)
 566 {
 567         return NULL;
 568 }
 569
 570 #if 0
 571 MonoArray *
 572 list_serial_devices (void)
 573 {
 574         MonoArray *array;
 575 #if defined(linux)
 576         /* Linux serial files are of the form ttyS[0-9]+ */
 577         GSList *l, *list = NULL;
 578         GDir* dir = g_dir_open ("/dev", 0, NULL);
 579         const char *filename;
 580         int i = 0;
 581
 582         while ((filename = g_dir_read_name (dir))) {
 583                 if (filename) {
 584                         if (!strncmp (filename, "ttyS", 4))
 585                                 list = g_slist_append (list, g_strconcat ("/dev/", filename, NULL));
 586                 }
 587         }
 588
 589         g_dir_close (dir);
 590
 591         array = mono_array_new (mono_domain_get (), mono_get_string_class (), g_slist_length (list));
 592         for (l = list; l; l = l->next) {
 593                 mono_array_set (array, gpointer, i++, mono_string_new (mono_domain_get (), (char*)l->data));
 594                 g_free (l->data);
 595         }
 596
 597         g_slist_free (list);
 598
 599 #else
 600 #warning "list_serial_devices isn't ported to this OS"
 601 #endif
 602
 603         return array;
 604 }
 605 #endif
 606