serialport.c

   1 /*
   2  * This file is part of the libserialport project.
   3  *
   4  * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
   5  * Copyright (C) 2010-2012 Uwe Hermann <uwe@hermann-uwe.de>
   6  * Copyright (C) 2013 Martin Ling <martin-libserialport@earth.li>
   7  *
   8  * This program is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU Lesser General Public License as
  10  * published by the Free Software Foundation, either version 3 of the
  11  * License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include <string.h>
  23 #include <sys/types.h>
  24 #include <sys/stat.h>
  25 #include <fcntl.h>
  26 #include <unistd.h>
  27 #include <stdlib.h>
  28 #include <errno.h>
  29 #ifdef _WIN32
  30 #include <windows.h>
  31 #include <tchar.h>
  32 #include <stdio.h>
  33 #else
  34 #include <termios.h>
  35 #include <sys/ioctl.h>
  36 #endif
  37 #ifdef __APPLE__
  38 #include <IOKit/IOKitLib.h>
  39 #include <IOKit/serial/IOSerialKeys.h>
  40 #include <sys/syslimits.h>
  41 #endif
  42 #ifdef __linux__
  43 #include "libudev.h"
  44 #include "linux/serial.h"
  45 #endif
  46
  47 #include "libserialport.h"
  48
  49 struct sp_port_data {
  50 #ifdef _WIN32
  51         DCB dcb;
  52 #else
  53         struct termios term;
  54         speed_t baud;
  55         int rts;
  56         int dtr;
  57 #endif
  58 };
  59
  60 int sp_get_port_by_name(const char *portname, struct sp_port **port_ptr)
  61 {
  62         struct sp_port *port;
  63         int len;
  64
  65         if (!port_ptr)
  66                 return SP_ERR_ARG;
  67
  68         *port_ptr = NULL;
  69
  70         if (!portname)
  71                 return SP_ERR_ARG;
  72
  73         if (!(port = malloc(sizeof(struct sp_port))))
  74                 return SP_ERR_MEM;
  75
  76         len = strlen(portname) + 1;
  77
  78         if (!(port->name = malloc(len)))
  79         {
  80                 free(port);
  81                 return SP_ERR_MEM;
  82         }
  83
  84         memcpy(port->name, portname, len);
  85
  86         *port_ptr = port;
  87
  88         return SP_OK;
  89 }
  90
  91 int sp_copy_port(const struct sp_port *port, struct sp_port **copy_ptr)
  92 {
  93         if (!copy_ptr)
  94                 return SP_ERR_ARG;
  95
  96         *copy_ptr = NULL;
  97
  98         if (!port || !port->name)
  99                 return SP_ERR_ARG;
 100
 101         return sp_get_port_by_name(port->name, copy_ptr);
 102 }
 103
 104 void sp_free_port(struct sp_port *port)
 105 {
 106         if (!port)
 107                 return;
 108
 109         if (port->name)
 110                 free(port->name);
 111
 112         free(port);
 113 }
 114
 115 static struct sp_port **sp_list_append(struct sp_port **list, const char *portname)
 116 {
 117         void *tmp;
 118         unsigned int count;
 119
 120         for (count = 0; list[count]; count++);
 121         if (!(tmp = realloc(list, sizeof(struct sp_port *) * (count + 2))))
 122                 goto fail;
 123         list = tmp;
 124         if (sp_get_port_by_name(portname, &list[count]) != SP_OK)
 125                 goto fail;
 126         list[count + 1] = NULL;
 127         return list;
 128
 129 fail:
 130         sp_free_port_list(list);
 131         return NULL;
 132 }
 133
 134 int sp_list_ports(struct sp_port ***list_ptr)
 135 {
 136         struct sp_port **list;
 137         int ret = SP_OK;
 138
 139         if (!(list = malloc(sizeof(struct sp_port **))))
 140                 return SP_ERR_MEM;
 141
 142         list[0] = NULL;
 143
 144 #ifdef _WIN32
 145         HKEY key;
 146         TCHAR *value, *data;
 147         DWORD max_value_len, max_data_size, max_data_len;
 148         DWORD value_len, data_size, data_len;
 149         DWORD type, index = 0;
 150         char *name;
 151         int name_len;
 152
 153         if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, _T("HARDWARE\\DEVICEMAP\\SERIALCOMM"),
 154                         0, KEY_QUERY_VALUE, &key) != ERROR_SUCCESS)
 155         {
 156                 ret = SP_ERR_FAIL;
 157                 goto out_done;
 158         }
 159         if (RegQueryInfoKey(key, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 160                                 &max_value_len, &max_data_size, NULL, NULL) != ERROR_SUCCESS)
 161         {
 162                 ret = SP_ERR_FAIL;
 163                 goto out_close;
 164         }
 165         max_data_len = max_data_size / sizeof(TCHAR);
 166         if (!(value = malloc((max_value_len + 1) * sizeof(TCHAR))))
 167         {
 168                 ret = SP_ERR_MEM;
 169                 goto out_close;
 170         }
 171         if (!(data = malloc((max_data_len + 1) * sizeof(TCHAR))))
 172         {
 173                 ret = SP_ERR_MEM;
 174                 goto out_free_value;
 175         }
 176         while (
 177                 value_len = max_value_len + 1,
 178                 data_size = max_data_size,
 179                 RegEnumValue(key, index, value, &value_len,
 180                         NULL, &type, (LPBYTE)data, &data_size) == ERROR_SUCCESS)
 181         {
 182                 data_len = data_size / sizeof(TCHAR);
 183                 data[data_len] = '\0';
 184 #ifdef UNICODE
 185                 name_len = WideCharToMultiByte(CP_ACP, 0, data, -1, NULL, 0, NULL, NULL)
 186 #else
 187                 name_len = data_len + 1;
 188 #endif
 189                 if (!(name = malloc(name_len)))
 190                 {
 191                         ret = SP_ERR_MEM;
 192                         goto out;
 193                 }
 194 #ifdef UNICODE
 195                 WideCharToMultiByte(CP_ACP, 0, data, -1, name, name_len, NULL, NULL);
 196 #else
 197                 strcpy(name, data);
 198 #endif
 199                 if (type == REG_SZ && !(list = sp_list_append(list, name)))
 200                 {
 201                         ret = SP_ERR_MEM;
 202                         goto out;
 203                 }
 204                 index++;
 205         }
 206 out:
 207         free(data);
 208 out_free_value:
 209         free(value);
 210 out_close:
 211         RegCloseKey(key);
 212 out_done:
 213 #endif
 214 #ifdef __APPLE__
 215         mach_port_t master;
 216         CFMutableDictionaryRef classes;
 217         io_iterator_t iter;
 218         char *path;
 219         io_object_t port;
 220         CFTypeRef cf_path;
 221         Boolean result;
 222
 223         if (IOMasterPort(MACH_PORT_NULL, &master) != KERN_SUCCESS)
 224         {
 225                 ret = SP_ERR_FAIL;
 226                 goto out_done;
 227         }
 228
 229         if (!(classes = IOServiceMatching(kIOSerialBSDServiceValue)))
 230         {
 231                 ret = SP_ERR_FAIL;
 232                 goto out_done;
 233         }
 234
 235         CFDictionarySetValue(classes,
 236                         CFSTR(kIOSerialBSDTypeKey), CFSTR(kIOSerialBSDAllTypes));
 237
 238         if (IOServiceGetMatchingServices(master, classes, &iter) != KERN_SUCCESS)
 239         {
 240                 ret = SP_ERR_FAIL;
 241                 goto out_done;
 242         }
 243
 244         if (!(path = malloc(PATH_MAX)))
 245         {
 246                 ret = SP_ERR_MEM;
 247                 goto out_release;
 248         }
 249
 250         while ((port = IOIteratorNext(iter))) {
 251                 cf_path = IORegistryEntryCreateCFProperty(port,
 252                                 CFSTR(kIOCalloutDeviceKey), kCFAllocatorDefault, 0);
 253                 if (cf_path) {
 254                         result = CFStringGetCString(cf_path,
 255                                         path, PATH_MAX, kCFStringEncodingASCII);
 256                         CFRelease(cf_path);
 257                         if (result && !(list = sp_list_append(list, path)))
 258                         {
 259                                 ret = SP_ERR_MEM;
 260                                 IOObjectRelease(port);
 261                                 goto out;
 262                         }
 263                 }
 264                 IOObjectRelease(port);
 265         }
 266 out:
 267         free(path);
 268 out_release:
 269         IOObjectRelease(iter);
 270 out_done:
 271 #endif
 272 #ifdef __linux__
 273         struct udev *ud;
 274         struct udev_enumerate *ud_enumerate;
 275         struct udev_list_entry *ud_list;
 276         struct udev_list_entry *ud_entry;
 277         const char *path;
 278         struct udev_device *ud_dev, *ud_parent;
 279         const char *name;
 280         const char *driver;
 281         int fd, ioctl_result;
 282         struct serial_struct serial_info;
 283
 284         ud = udev_new();
 285         ud_enumerate = udev_enumerate_new(ud);
 286         udev_enumerate_add_match_subsystem(ud_enumerate, "tty");
 287         udev_enumerate_scan_devices(ud_enumerate);
 288         ud_list = udev_enumerate_get_list_entry(ud_enumerate);
 289         udev_list_entry_foreach(ud_entry, ud_list)
 290         {
 291                 path = udev_list_entry_get_name(ud_entry);
 292                 ud_dev = udev_device_new_from_syspath(ud, path);
 293                 /* If there is no parent device, this is a virtual tty. */
 294                 ud_parent = udev_device_get_parent(ud_dev);
 295                 if (ud_parent == NULL)
 296                 {
 297                         udev_device_unref(ud_dev);
 298                         continue;
 299                 }
 300                 name = udev_device_get_devnode(ud_dev);
 301                 /* The serial8250 driver has a hardcoded number of ports.
 302                  * The only way to tell which actually exist on a given system
 303                  * is to try to open them and make an ioctl call. */
 304                 driver = udev_device_get_driver(ud_parent);
 305                 if (driver && !strcmp(driver, "serial8250"))
 306                 {
 307                         if ((fd = open(name, O_RDWR | O_NONBLOCK | O_NOCTTY)) < 0)
 308                                 goto skip;
 309                         ioctl_result = ioctl(fd, TIOCGSERIAL, &serial_info);
 310                         close(fd);
 311                         if (ioctl_result != 0)
 312                                 goto skip;
 313                         if (serial_info.type == PORT_UNKNOWN)
 314                                 goto skip;
 315                 }
 316                 list = sp_list_append(list, name);
 317 skip:
 318                 udev_device_unref(ud_dev);
 319                 if (!list)
 320                 {
 321                         ret = SP_ERR_MEM;
 322                         goto out;
 323                 }
 324         }
 325 out:
 326         udev_enumerate_unref(ud_enumerate);
 327         udev_unref(ud);
 328 #endif
 329
 330         if (ret == SP_OK)
 331         {
 332                 *list_ptr = list;
 333         }
 334         else
 335         {
 336                 if (list)
 337                         sp_free_port_list(list);
 338
 339                 *list_ptr = NULL;
 340         }
 341
 342         return ret;
 343 }
 344
 345 void sp_free_port_list(struct sp_port **list)
 346 {
 347         unsigned int i;
 348
 349         for (i = 0; list[i]; i++)
 350                 sp_free_port(list[i]);
 351         free(list);
 352 }
 353
 354 static int sp_validate_port(struct sp_port *port)
 355 {
 356         if (port == NULL)
 357                 return 0;
 358 #ifdef _WIN32
 359         if (port->hdl == INVALID_HANDLE_VALUE)
 360                 return 0;
 361 #else
 362         if (port->fd < 0)
 363                 return 0;
 364 #endif
 365         return 1;
 366 }
 367
 368 #define CHECK_PORT() do { if (!sp_validate_port(port)) return SP_ERR_ARG; } while (0)
 369
 370 int sp_open(struct sp_port *port, int flags)
 371 {
 372         if (!port)
 373                 return SP_ERR_ARG;
 374
 375 #ifdef _WIN32
 376         DWORD desired_access = 0, flags_and_attributes = 0;
 377         char *escaped_port_name;
 378
 379         /* Prefix port name with '\\.\' to work with ports above COM9. */
 380         if (!(escaped_port_name = malloc(strlen(port->name + 5))))
 381                 return SP_ERR_MEM;
 382         sprintf(escaped_port_name, "\\\\.\\%s", port->name);
 383
 384         /* Map 'flags' to the OS-specific settings. */
 385         desired_access |= GENERIC_READ;
 386         flags_and_attributes = FILE_ATTRIBUTE_NORMAL;
 387         if (flags & SP_MODE_RDWR)
 388                 desired_access |= GENERIC_WRITE;
 389         if (flags & SP_MODE_NONBLOCK)
 390                 flags_and_attributes |= FILE_FLAG_OVERLAPPED;
 391
 392         port->hdl = CreateFile(escaped_port_name, desired_access, 0, 0,
 393                          OPEN_EXISTING, flags_and_attributes, 0);
 394
 395         free(escaped_port_name);
 396
 397         if (port->hdl == INVALID_HANDLE_VALUE)
 398                 return SP_ERR_FAIL;
 399 #else
 400         int flags_local = 0;
 401
 402         /* Map 'flags' to the OS-specific settings. */
 403         if (flags & SP_MODE_RDWR)
 404                 flags_local |= O_RDWR;
 405         if (flags & SP_MODE_RDONLY)
 406                 flags_local |= O_RDONLY;
 407         if (flags & SP_MODE_NONBLOCK)
 408                 flags_local |= O_NONBLOCK;
 409
 410         if ((port->fd = open(port->name, flags_local)) < 0)
 411                 return SP_ERR_FAIL;
 412 #endif
 413
 414         return SP_OK;
 415 }
 416
 417 int sp_close(struct sp_port *port)
 418 {
 419         CHECK_PORT();
 420
 421 #ifdef _WIN32
 422         /* Returns non-zero upon success, 0 upon failure. */
 423         if (CloseHandle(port->hdl) == 0)
 424                 return SP_ERR_FAIL;
 425 #else
 426         /* Returns 0 upon success, -1 upon failure. */
 427         if (close(port->fd) == -1)
 428                 return SP_ERR_FAIL;
 429 #endif
 430
 431         return SP_OK;
 432 }
 433
 434 int sp_flush(struct sp_port *port)
 435 {
 436         CHECK_PORT();
 437
 438 #ifdef _WIN32
 439         /* Returns non-zero upon success, 0 upon failure. */
 440         if (PurgeComm(port->hdl, PURGE_RXCLEAR | PURGE_TXCLEAR) == 0)
 441                 return SP_ERR_FAIL;
 442 #else
 443         /* Returns 0 upon success, -1 upon failure. */
 444         if (tcflush(port->fd, TCIOFLUSH) < 0)
 445                 return SP_ERR_FAIL;
 446 #endif
 447         return SP_OK;
 448 }
 449
 450 int sp_write(struct sp_port *port, const void *buf, size_t count)
 451 {
 452         CHECK_PORT();
 453
 454         if (!buf)
 455                 return SP_ERR_ARG;
 456
 457 #ifdef _WIN32
 458         DWORD written = 0;
 459
 460         /* Returns non-zero upon success, 0 upon failure. */
 461         if (WriteFile(port->hdl, buf, count, &written, NULL) == 0)
 462                 return SP_ERR_FAIL;
 463         return written;
 464 #else
 465         /* Returns the number of bytes written, or -1 upon failure. */
 466         ssize_t written = write(port->fd, buf, count);
 467
 468         if (written < 0)
 469                 return SP_ERR_FAIL;
 470         else
 471                 return written;
 472 #endif
 473 }
 474
 475 int sp_read(struct sp_port *port, void *buf, size_t count)
 476 {
 477         CHECK_PORT();
 478
 479         if (!buf)
 480                 return SP_ERR_ARG;
 481
 482 #ifdef _WIN32
 483         DWORD bytes_read = 0;
 484
 485         /* Returns non-zero upon success, 0 upon failure. */
 486         if (ReadFile(port->hdl, buf, count, &bytes_read, NULL) == 0)
 487                 return SP_ERR_FAIL;
 488         return bytes_read;
 489 #else
 490         ssize_t bytes_read;
 491
 492         /* Returns the number of bytes read, or -1 upon failure. */
 493         if ((bytes_read = read(port->fd, buf, count)) < 0)
 494                 return SP_ERR_FAIL;
 495         return bytes_read;
 496 #endif
 497 }
 498
 499 static int start_config(struct sp_port *port, struct sp_port_data *data)
 500 {
 501         CHECK_PORT();
 502 #ifdef _WIN32
 503         if (!GetCommState(port->hdl, &data->dcb))
 504                 return SP_ERR_FAIL;
 505 #else
 506         if (tcgetattr(port->fd, &data->term) < 0)
 507                 return SP_ERR_FAIL;
 508 #endif
 509         return SP_OK;
 510 }
 511
 512 static int set_baudrate(struct sp_port_data *data, int baudrate)
 513 {
 514 #ifdef _WIN32
 515         switch (baudrate) {
 516         /*
 517          * The baudrates 50/75/134/150/200/1800/230400/460800 do not seem to
 518          * have documented CBR_* macros.
 519          */
 520         case 110:
 521                 data->dcb.BaudRate = CBR_110;
 522                 break;
 523         case 300:
 524                 data->dcb.BaudRate = CBR_300;
 525                 break;
 526         case 600:
 527                 data->dcb.BaudRate = CBR_600;
 528                 break;
 529         case 1200:
 530                 data->dcb.BaudRate = CBR_1200;
 531                 break;
 532         case 2400:
 533                 data->dcb.BaudRate = CBR_2400;
 534                 break;
 535         case 4800:
 536                 data->dcb.BaudRate = CBR_4800;
 537                 break;
 538         case 9600:
 539                 data->dcb.BaudRate = CBR_9600;
 540                 break;
 541         case 14400:
 542                 data->dcb.BaudRate = CBR_14400; /* Not available on Unix? */
 543                 break;
 544         case 19200:
 545                 data->dcb.BaudRate = CBR_19200;
 546                 break;
 547         case 38400:
 548                 data->dcb.BaudRate = CBR_38400;
 549                 break;
 550         case 57600:
 551                 data->dcb.BaudRate = CBR_57600;
 552                 break;
 553         case 115200:
 554                 data->dcb.BaudRate = CBR_115200;
 555                 break;
 556         case 128000:
 557                 data->dcb.BaudRate = CBR_128000; /* Not available on Unix? */
 558                 break;
 559         case 256000:
 560                 data->dcb.BaudRate = CBR_256000; /* Not available on Unix? */
 561                 break;
 562         default:
 563                 return SP_ERR_ARG;
 564         }
 565 #else
 566         switch (baudrate) {
 567         case 50:
 568                 data->baud = B50;
 569                 break;
 570         case 75:
 571                 data->baud = B75;
 572                 break;
 573         case 110:
 574                 data->baud = B110;
 575                 break;
 576         case 134:
 577                 data->baud = B134;
 578                 break;
 579         case 150:
 580                 data->baud = B150;
 581                 break;
 582         case 200:
 583                 data->baud = B200;
 584                 break;
 585         case 300:
 586                 data->baud = B300;
 587                 break;
 588         case 600:
 589                 data->baud = B600;
 590                 break;
 591         case 1200:
 592                 data->baud = B1200;
 593                 break;
 594         case 1800:
 595                 data->baud = B1800;
 596                 break;
 597         case 2400:
 598                 data->baud = B2400;
 599                 break;
 600         case 4800:
 601                 data->baud = B4800;
 602                 break;
 603         case 9600:
 604                 data->baud = B9600;
 605                 break;
 606         case 19200:
 607                 data->baud = B19200;
 608                 break;
 609         case 38400:
 610                 data->baud = B38400;
 611                 break;
 612         case 57600:
 613                 data->baud = B57600;
 614                 break;
 615         case 115200:
 616                 data->baud = B115200;
 617                 break;
 618         case 230400:
 619                 data->baud = B230400;
 620                 break;
 621 #if !defined(__APPLE__) && !defined(__OpenBSD__)
 622         case 460800:
 623                 data->baud = B460800;
 624                 break;
 625 #endif
 626         default:
 627                 return SP_ERR_ARG;
 628         }
 629 #endif
 630         return SP_OK;
 631 }
 632
 633 static int set_bits(struct sp_port_data *data, int bits)
 634 {
 635 #ifdef _WIN32
 636         data->dcb.ByteSize = bits;
 637 #else
 638         data->term.c_cflag &= ~CSIZE;
 639         switch (bits) {
 640         case 8:
 641                 data->term.c_cflag |= CS8;
 642                 break;
 643         case 7:
 644                 data->term.c_cflag |= CS7;
 645                 break;
 646         case 6:
 647                 data->term.c_cflag |= CS6;
 648                 break;
 649         default:
 650                 return SP_ERR_ARG;
 651         }
 652 #endif
 653         return SP_OK;
 654 }
 655
 656 static int set_parity(struct sp_port_data *data, int parity)
 657 {
 658 #ifdef _WIN32
 659         switch (parity) {
 660         /* Note: There's also SPACEPARITY, MARKPARITY (unneeded so far). */
 661         case SP_PARITY_NONE:
 662                 data->dcb.Parity = NOPARITY;
 663                 break;
 664         case SP_PARITY_EVEN:
 665                 data->dcb.Parity = EVENPARITY;
 666                 break;
 667         case SP_PARITY_ODD:
 668                 data->dcb.Parity = ODDPARITY;
 669                 break;
 670         default:
 671                 return SP_ERR_ARG;
 672         }
 673 #else
 674         data->term.c_iflag &= ~IGNPAR;
 675         data->term.c_cflag &= ~(PARENB | PARODD);
 676         switch (parity) {
 677         case SP_PARITY_NONE:
 678                 data->term.c_iflag |= IGNPAR;
 679                 break;
 680         case SP_PARITY_EVEN:
 681                 data->term.c_cflag |= PARENB;
 682                 break;
 683         case SP_PARITY_ODD:
 684                 data->term.c_cflag |= PARENB | PARODD;
 685                 break;
 686         default:
 687                 return SP_ERR_ARG;
 688         }
 689 #endif
 690         return SP_OK;
 691 }
 692
 693 static int set_stopbits(struct sp_port_data *data, int stopbits)
 694 {
 695 #ifdef _WIN32
 696         switch (stopbits) {
 697         /* Note: There's also ONE5STOPBITS == 1.5 (unneeded so far). */
 698         case 1:
 699                 data->dcb.StopBits = ONESTOPBIT;
 700                 break;
 701         case 2:
 702                 data->dcb.StopBits = TWOSTOPBITS;
 703                 break;
 704         default:
 705                 return SP_ERR_ARG;
 706         }
 707 #else
 708         data->term.c_cflag &= ~CSTOPB;
 709         switch (stopbits) {
 710         case 1:
 711                 data->term.c_cflag &= ~CSTOPB;
 712                 break;
 713         case 2:
 714                 data->term.c_cflag |= CSTOPB;
 715                 break;
 716         default:
 717                 return SP_ERR_ARG;
 718         }
 719 #endif
 720         return SP_OK;
 721 }
 722
 723 static int set_flowcontrol(struct sp_port_data *data, int flowcontrol)
 724 {
 725 #ifndef _WIN32
 726         data->term.c_iflag &= ~(IXON | IXOFF | IXANY);
 727         data->term.c_cflag &= ~CRTSCTS;
 728         switch (flowcontrol) {
 729         case 0:
 730                 /* No flow control. */
 731                 break;
 732         case 1:
 733                 data->term.c_cflag |= CRTSCTS;
 734                 break;
 735         case 2:
 736                 data->term.c_iflag |= IXON | IXOFF | IXANY;
 737                 break;
 738         default:
 739                 return SP_ERR_ARG;
 740         }
 741 #endif
 742         return SP_OK;
 743 }
 744
 745 static int set_rts(struct sp_port_data *data, int rts)
 746 {
 747 #ifdef _WIN32
 748         if (rts != -1) {
 749                 if (rts)
 750                         data->dcb.fRtsControl = RTS_CONTROL_ENABLE;
 751                 else
 752                         data->dcb.fRtsControl = RTS_CONTROL_DISABLE;
 753         }
 754 #else
 755         data->rts = rts;
 756 #endif
 757         return SP_OK;
 758 }
 759
 760 static int set_dtr(struct sp_port_data *data, int dtr)
 761 {
 762 #ifdef _WIN32
 763         if (dtr != -1) {
 764                 if (dtr)
 765                         data->dcb.fDtrControl = DTR_CONTROL_ENABLE;
 766                 else
 767                         data->dcb.fDtrControl = DTR_CONTROL_DISABLE;
 768         }
 769 #else
 770         data->dtr = dtr;
 771 #endif
 772         return SP_OK;
 773 }
 774
 775 static int apply_config(struct sp_port *port, struct sp_port_data *data)
 776 {
 777 #ifdef _WIN32
 778         if (!SetCommState(port->hdl, &data->dcb))
 779                 return SP_ERR_FAIL;
 780 #else
 781         int controlbits;
 782
 783         /* Turn off all serial port cooking. */
 784         data->term.c_iflag &= ~(ISTRIP | INLCR | ICRNL);
 785         data->term.c_oflag &= ~(ONLCR | OCRNL | ONOCR);
 786 #if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
 787         data->term.c_oflag &= ~OFILL;
 788 #endif
 789         /* Disable canonical mode, and don't echo input characters. */
 790         data->term.c_lflag &= ~(ICANON | ECHO);
 791
 792         /* Ignore modem status lines; enable receiver */
 793         data->term.c_cflag |= (CLOCAL | CREAD);
 794
 795         /* Write the configured settings. */
 796         if (tcsetattr(port->fd, TCSADRAIN, &data->term) < 0)
 797                 return SP_ERR_FAIL;
 798
 799         if (cfsetospeed(&data->term, data->baud) < 0)
 800                 return SP_ERR_FAIL;
 801
 802         if (cfsetispeed(&data->term, data->baud) < 0)
 803                 return SP_ERR_FAIL;
 804
 805         if (data->rts != -1) {
 806                 controlbits = TIOCM_RTS;
 807                 if (ioctl(port->fd, data->rts ? TIOCMBIS : TIOCMBIC,
 808                                 &controlbits) < 0)
 809                         return SP_ERR_FAIL;
 810         }
 811
 812         if (data->dtr != -1) {
 813                 controlbits = TIOCM_DTR;
 814                 if (ioctl(port->fd, data->dtr ? TIOCMBIS : TIOCMBIC,
 815                                 &controlbits) < 0)
 816                         return SP_ERR_FAIL;
 817         }
 818 #endif
 819         return SP_OK;
 820 }
 821
 822 #define TRY(x) do { int ret = x; if (ret != SP_OK) return ret; } while (0)
 823
 824 int sp_set_params(struct sp_port *port, int baudrate, int bits, int parity,
 825                 int stopbits, int flowcontrol, int rts, int dtr)
 826 {
 827         struct sp_port_data data;
 828
 829         TRY(start_config(port, &data));
 830         TRY(set_baudrate(&data, baudrate));
 831         TRY(set_bits(&data, bits));
 832         TRY(set_parity(&data, parity));
 833         TRY(set_stopbits(&data, stopbits));
 834         TRY(set_flowcontrol(&data, flowcontrol));
 835         TRY(set_rts(&data, rts));
 836         TRY(set_dtr(&data, dtr));
 837         TRY(apply_config(port, &data));
 838
 839         return SP_OK;
 840 }
 841
 842 int sp_last_error_code(void)
 843 {
 844 #ifdef _WIN32
 845         return GetLastError();
 846 #else
 847         return errno;
 848 #endif
 849 }
 850
 851 char *sp_last_error_message(void)
 852 {
 853 #ifdef _WIN32
 854         LPVOID message;
 855         DWORD error = GetLastError();
 856
 857         FormatMessage(
 858                 FORMAT_MESSAGE_ALLOCATE_BUFFER |
 859                 FORMAT_MESSAGE_FROM_SYSTEM |
 860                 FORMAT_MESSAGE_IGNORE_INSERTS,
 861                 NULL,
 862                 error,
 863                 MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
 864                 (LPTSTR) &message,
 865                 0, NULL );
 866
 867         return message;
 868 #else
 869         return strerror(errno);
 870 #endif
 871 }
 872
 873 void sp_free_error_message(char *message)
 874 {
 875 #ifdef _WIN32
 876         LocalFree(message);
 877 #else
 878         (void)message;
 879 #endif
 880 }