mdw@git.distorted.org.uk Git - jog/blob - tx-serial-unix.c

   1 /* -*-c-*-
   2  *
   3  * $Id: tx-serial-unix.c,v 1.3 2002/02/02 19:17:33 mdw Exp $
   4  *
   5  * Unix/POSIX serial transport
   6  *
   7  * (c) 2001 Mark Wooding
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Jog: Programming for a jogging machine.
  13  *
  14  * Jog is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * Jog is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with Jog; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Revision history --------------------------------------------------*
  30  *
  31  * $Log: tx-serial-unix.c,v $
  32  * Revision 1.3  2002/02/02 19:17:33  mdw
  33  * Missing header.
  34  *
  35  * Revision 1.2  2002/01/30 09:24:24  mdw
  36  * Restructure for new transport configuration interface.
  37  *
  38  * Revision 1.1  2002/01/25 19:34:45  mdw
  39  * Initial revision
  40  *
  41  */
  42
  43 /*----- Header files ------------------------------------------------------*/
  44
  45 #ifdef HAVE_CONFIG_H
  46 #  include "config.h"
  47 #endif
  48
  49 #include <assert.h>
  50 #include <errno.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <string.h>
  54
  55 #include <sys/types.h>
  56 #include <termios.h>
  57 #include <unistd.h>
  58 #include <fcntl.h>
  59
  60 #include <mLib/darray.h>
  61 #include <mLib/fdflags.h>
  62 #include <mLib/sub.h>
  63
  64 #include "err.h"
  65 #include "serial.h"
  66 #include "txport.h"
  67
  68 #ifndef O_NOCTTY
  69 #  define O_NOCTTY 0
  70 #endif
  71
  72 /*----- Data structures ---------------------------------------------------*/
  73
  74 typedef struct txsu {
  75   txport tx;                            /* Transport base */
  76   struct txsu *next, **prev;            /* Chain of serial transports */
  77   int fd;                               /* File descriptor */
  78   serial_config sc;                     /* Internal serial config */
  79   struct termios ta, old_ta;            /* External serial configs */
  80 } txsu;
  81
  82 /*----- Static variables --------------------------------------------------*/
  83
  84 struct baudmap { unsigned long baud; unsigned long magic; };
  85
  86 static const struct baudmap baudmap[] = {
  87 #ifdef B50
  88   {     50,     B50 },
  89 #endif
  90 #ifdef B75
  91   {     75,     B75 },
  92 #endif
  93 #ifdef B110
  94   {    110,    B110 },
  95 #endif
  96 #ifdef B134
  97   {    134,    B134 },
  98 #endif
  99 #ifdef B150
 100   {    150,    B150 },
 101 #endif
 102 #ifdef B200
 103   {    200,    B200 },
 104 #endif
 105 #ifdef B300
 106   {    300,    B300 },
 107 #endif
 108 #ifdef B600
 109   {    600,    B600 },
 110 #endif
 111 #ifdef B1200
 112   {   1200,   B1200 },
 113 #endif
 114 #ifdef B1800
 115   {   1800,   B1800 },
 116 #endif
 117 #ifdef B2400
 118   {   2400,   B2400 },
 119 #endif
 120 #ifdef B4800
 121   {   4800,   B4800 },
 122 #endif
 123 #ifdef B9600
 124   {   9600,   B9600 },
 125 #endif
 126 #ifdef B19200
 127   {  19200,  B19200 },
 128 #endif
 129 #ifdef B38400
 130   {  38400,  B38400 },
 131 #endif
 132 #ifdef B57600
 133   {  57600,  B57600 },
 134 #endif
 135 #ifdef B115200
 136   { 115200, B115200 },
 137 #endif
 138 #ifdef B230400
 139   { 230400, B230400 },
 140 #endif
 141   {      0,       0 }
 142 };
 143
 144 static unsigned long csize[] = { CS5, CS6, CS7, CS8 };
 145
 146 static txsu *active = 0;
 147
 148 /*----- Main code ---------------------------------------------------------*/
 149
 150 /* --- @txsu_shutdown@ --- *
 151  *
 152  * Arguments:   ---
 153  *
 154  * Returns:     ---
 155  *
 156  * Use:         Restores terminal settings on exit.
 157  */
 158
 159 void txsu_shutdown(void)
 160 {
 161   txsu *tx;
 162
 163   for (tx = active; tx; tx = tx->next)
 164     tcsetattr(tx->fd, TCSAFLUSH, &tx->old_ta);
 165 }
 166
 167 /* --- @setconfig@ --- *
 168  *
 169  * Arguments:   @txsu *tx@ = pointer to serial transport
 170  *              @serial_config *sc@ = pointer to configuration to set
 171  *
 172  * Returns:     Zero if OK, nonzero on error.
 173  *
 174  * Use:         Updates the external configuration from an internal
 175  *              representation.
 176  */
 177
 178 static int setconfig(txsu *tx, serial_config *sc)
 179 {
 180   struct termios *ta = &tx->ta;
 181   const struct baudmap *b;
 182
 183   for (b = baudmap; b->baud && b->baud != sc->baud; b++)
 184     ;
 185   if (!b->baud ||
 186       sc->wordlen < 5 || sc->wordlen > 8 ||
 187       sc->stopbits < 1 || sc->stopbits > 2) {
 188     err_report(ERR_TXPORT, ERRTX_CONFIG, 0, "bad serial configuration");
 189     return (-1);
 190   }
 191
 192   ta->c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL);
 193   ta->c_oflag &= ~OPOST;
 194   ta->c_lflag &= ~(ECHO|ECHONL|ICANON|ISIG|IEXTEN);
 195   ta->c_cc[VMIN] = 1;
 196   ta->c_cc[VTIME] = 0;
 197
 198   cfsetospeed(ta, b->magic);
 199   cfsetispeed(ta, b->magic);
 200   ta->c_cflag = (ta->c_cflag & ~CSIZE) | csize[sc->wordlen - 5];
 201   switch (sc->parity) {
 202     case PARITY_NONE: ta->c_cflag &= ~PARENB; break;
 203     case PARITY_ODD:  ta->c_cflag |= PARENB | PARODD; break;
 204     case PARITY_EVEN: ta->c_cflag |= PARENB; ta->c_cflag &= ~PARODD; break;
 205   }
 206   switch (sc->stopbits) {
 207     case 1: ta->c_cflag &= ~CSTOPB; break;
 208     case 2: ta->c_cflag |= CSTOPB; break;
 209   }
 210
 211   switch (sc->flow) {
 212     case FLOW_NONE:
 213       ta->c_cflag &= ~CRTSCTS;
 214       ta->c_iflag &= ~(IXON | IXOFF);
 215       break;
 216     case FLOW_XONXOFF:
 217       ta->c_cflag &= ~CRTSCTS;
 218       ta->c_iflag |= IXON | IXOFF;
 219       break;
 220     case FLOW_RTSCTS:
 221       ta->c_cflag |= CRTSCTS;
 222       ta->c_iflag &= ~(IXON | IXOFF);
 223       break;
 224   }
 225
 226   if (tcsetattr(tx->fd, TCSAFLUSH, ta)) {
 227     err_report(ERR_TXPORT, ERRTX_CREATE, errno,
 228                "couldn't set terminal attributes: %s", strerror(errno));
 229     return (-1);
 230   }
 231
 232   tx->sc = *sc;
 233   return (0);
 234 }
 235
 236 /* --- @txsu_create@ --- *
 237  *
 238  * Arguments:   @const char *file@ = filename for serial port
 239  *
 240  * Returns:     Pointer to created transport block.
 241  *
 242  * Use:         Creates a serial port transport.
 243  */
 244
 245 txport *txsu_create(const char *file)
 246 {
 247   txsu *tx = CREATE(txsu);
 248   serial_config sc = SERIAL_INIT;
 249
 250   if ((tx->fd = open(file, O_RDWR | O_NOCTTY | O_NONBLOCK)) < 0) {
 251     err_report(ERR_TXPORT, ERRTX_CREATE, errno,
 252                "couldn't open device `%s': %s", file, strerror(errno));
 253     goto fail_0;
 254   }
 255   if (fdflags(tx->fd, O_NONBLOCK, 0, 0, 0)) {
 256     err_report(ERR_TXPORT, ERRTX_CREATE, errno,
 257                "fcntl(clear O_NONBLOCK): %s", file, strerror(errno));
 258     goto fail_1;
 259   }
 260
 261   if (tcgetattr(tx->fd, &tx->old_ta)) {
 262     err_report(ERR_TXPORT, ERRTX_CREATE, errno,
 263                "couldn't get terminal attributes: %s", strerror(errno));
 264     goto fail_1;
 265   }
 266   tx->ta = tx->old_ta;
 267   if (setconfig(tx, &sc))
 268     goto fail_1;
 269
 270   tx->next = active;
 271   tx->prev = &active;
 272   active = tx;
 273   return (&tx->tx);
 274
 275   /* --- Tidy up because it all went horribly wrong --- */
 276
 277 fail_1:
 278   close(tx->fd);
 279 fail_0:
 280   DESTROY(tx);
 281   return (0);
 282 }
 283
 284 /* --- @txsu_configure@ --- *
 285  *
 286  * Arguments:   @txport *txg@ = pointer to transport block
 287  *              @const char *k@ = configuration keyword
 288  *              @const char *v@ = value
 289  *
 290  * Returns:     Nonzero if handled, zero otherwise.
 291  *
 292  * Use:         Configures a serial port.
 293  */
 294
 295 int txsu_configure(txport *txg, const char *k, const char *v)
 296 {
 297   txsu *tx = (txsu *)txg;
 298   serial_config sc = tx->sc;
 299
 300   if (!v) {
 301     err_report(ERR_TXPORT, ERRTX_CONFIG, 0,
 302                "syntax error in serial config `%s'", k);
 303     return (-1);
 304   }
 305   if (serial_parse(&sc, k, v)) {
 306     err_report(ERR_TXPORT, ERRTX_CONFIG, 0,
 307                "syntax error in serial config `%s=%s'", k, v);
 308     return (-1);
 309   }
 310   if (setconfig(tx, &sc))
 311     return (-1);
 312   return (1);
 313 }
 314
 315 /* --- @txsu_write@ --- *
 316  *
 317  * Arguments:   @txport *txg@ = pointer to transport context
 318  *              @const void *p@ = pointer to buffer
 319  *              @size_t sz@ = size of the buffer
 320  *
 321  * Returns:     Number of bytes written, or @-1@ on error.
 322  *
 323  * Use:         Writes data to a transport.
 324  */
 325
 326 ssize_t txsu_write(txport *txg, const void *p, size_t sz)
 327 {
 328   txsu *tx = (txsu *)txg;
 329
 330   return (write(tx->fd, p, sz));
 331 }
 332
 333 /* --- @txsu_fetch@ --- *
 334  *
 335  * Arguments:   @void *txv@ = pointer to transport context
 336  *
 337  * Returns:     Nothing of interest.
 338  *
 339  * Use:         Thread to fetch data from a serial port.
 340  */
 341
 342 void *txsu_fetch(void *txv)
 343 {
 344   txsu *tx = txv;
 345   unsigned char buf[BUFSIZ];
 346   ssize_t n;
 347   int e;
 348
 349   /* --- Read data while it arrives --- */
 350
 351   for (;;) {
 352     n = read(tx->fd, buf, sizeof(buf));
 353     if (n < 0) {
 354       err_report(ERR_TXPORT, ERRTX_READ, errno,
 355                  "error reading from serial port: %s", strerror(errno));
 356       break;
 357     }
 358 #ifdef TERMINAL_EOF
 359     if (!n) break;
 360 #else
 361     if (!n) continue;
 362 #endif
 363     if ((e = pthread_mutex_lock(&tx->tx.mx)) != 0) {
 364       err_report(ERR_TXPORT, ERRTX_READ, e,
 365                  "error locking mutex: %s", strerror(e));
 366       break;
 367     }
 368     DA_ENSURE(&tx->tx.buf, n);
 369     memcpy(DA(&tx->tx.buf) + DA_LEN(&tx->tx.buf), buf, n);
 370     DA_EXTEND(&tx->tx.buf, n);
 371     pthread_cond_signal(&tx->tx.cv);
 372     pthread_mutex_unlock(&tx->tx.mx);
 373   }
 374
 375   /* --- Deal with crapness --- */
 376
 377   e = pthread_mutex_lock(&tx->tx.mx);
 378   tx->tx.s = TX_CLOSE;
 379   pthread_cond_signal(&tx->tx.cv);
 380   pthread_mutex_unlock(&tx->tx.mx);
 381   return (0);
 382 }
 383
 384 /* --- @txsu_destroy@ --- *
 385  *
 386  * Arguments:   @txport *txg@ = pointer to transport context
 387  *
 388  * Returns:     ---
 389  *
 390  * Use:         Destroys a serial port transport.
 391  */
 392
 393 void txsu_destroy(txport *txg)
 394 {
 395   txsu *tx = (txsu *)txg;
 396
 397   tcsetattr(tx->fd, TCSAFLUSH, &tx->old_ta);
 398   close(tx->fd);
 399   *tx->prev = tx->next;
 400   if (tx->next)
 401     tx->next->prev = tx->prev;
 402   DESTROY(tx);
 403 }
 404
 405 /*----- That's all, folks -------------------------------------------------*/