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