streams/wvmodem.cc

   1 /*
   2  * Worldvisions Weaver Software:
   3  *   Copyright (C) 1997-2002 Net Integration Technologies, Inc.
   4  *   Copyright (C) 1999 Red Hat, Inc.
   5  *
   6  * Implementation of the WvModem class. Inherits from WvFile, but
   7  * handles various important details related to modems, like setting
   8  * the baud rate, checking carrier detect, and dropping DTR.
   9  *
  10  */
  11
  12 #include "wvmodem.h"
  13 #include <sys/ioctl.h>
  14
  15 #if HAVE_LINUX_SERIAL_H
  16 # include <linux/serial.h>
  17 #endif
  18
  19 #if ! HAVE_CFMAKERAW
  20 static inline void cfmakeraw(struct termios *termios_p)
  21 {
  22     termios_p->c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL|IXON);
  23     termios_p->c_oflag &= ~OPOST;
  24     termios_p->c_lflag &= ~(ECHO|ECHONL|ICANON|ISIG|IEXTEN);
  25     termios_p->c_cflag &= ~(CSIZE|PARENB);
  26     termios_p->c_cflag |= CS8;
  27 }
  28 #endif
  29
  30 struct SpeedLookup {
  31     int baud;
  32     speed_t speedt;
  33 };
  34
  35
  36 static SpeedLookup speeds[] = {
  37 #ifdef B460800
  38     {460800, B460800},
  39 #endif
  40 #ifdef B230400
  41     {230400, B230400},
  42 #endif
  43     {115200, B115200},
  44     { 57600, B57600},
  45     { 38400, B38400},
  46     { 19200, B19200},
  47     {  9600, B9600},
  48     {  4800, B4800},
  49     {  2400, B2400},
  50     {  1200, B1200},
  51     {   300, B300}
  52 };
  53
  54
  55 WvModemBase::WvModemBase(int _fd) : WvFile(_fd)
  56 {
  57     get_real_speed();
  58 }
  59
  60
  61 WvModemBase::~WvModemBase()
  62 {
  63     // nothing needed
  64 }
  65
  66
  67 int WvModemBase::get_real_speed()
  68 {
  69     speed_t s;
  70
  71     if (!isok()) return 0;
  72
  73     tcgetattr( getrfd(), &t );
  74     s = cfgetospeed( &t );
  75     for (unsigned int i = 0; i < sizeof(speeds) / sizeof(*speeds); i++)
  76     {
  77         if (speeds[i].speedt == s)
  78         {
  79             baud = speeds[i].baud;
  80             break;
  81         }
  82     }
  83
  84     return baud;
  85 }
  86
  87
  88 void WvModemBase::close()
  89 {
  90     // no file open, no need to close it
  91 }
  92
  93
  94 bool WvModemBase::carrier()
  95 {
  96     return true;
  97 }
  98
  99
 100 int WvModemBase::speed(int)
 101 {
 102     return baud;
 103 }
 104
 105
 106 void WvModemBase::hangup()
 107 {
 108     int i, oldbaud = baud;
 109
 110     if (die_fast || !isok()) return;
 111
 112     // politely abort any dial in progress, to avoid locking USR modems.
 113     // we should only do this if we have received any response from the modem,
 114     // so that WvModemScan can run faster.
 115     drain();
 116     write( "\r", 1 );
 117     // FIXME: should be iswritable, but based on the numer of msec params
 118     // tossed around I assume modems are very timing-sensitive
 119     for (i = 0; !select(200, false, true) && i < 10; i++)
 120         write( "\r", 1 );
 121     drain();
 122
 123     // drop DTR for a while, if still online
 124     if (carrier())
 125     {
 126         cfsetospeed( &t, B0 );
 127         tcsetattr( getrfd(), TCSANOW, &t );
 128         for (i = 0; carrier() && i < 10; i++)
 129             usleep( 100 * 1000 );
 130
 131         // raise DTR again, restoring the old baud rate
 132         speed(oldbaud);
 133     }
 134
 135     if (carrier())
 136     {
 137         // need to do +++ manual-disconnect stuff
 138         write( "+++", 3 );
 139         usleep( 1500 * 1000 );
 140         write( "ATH\r", 4 );
 141
 142         for (i = 0; carrier() && i < 5; i++)
 143             usleep( 100 * 1000 );
 144     }
 145 }
 146
 147
 148
 149 WvModem::WvModem(WvStringParm filename, int _baud, bool rtscts, bool _no_reset)
 150     : WvModemBase(), lock(filename), log("WvModem", WvLog::Debug1)
 151 {
 152     closing = false;
 153     baud = _baud;
 154     die_fast = false;
 155     no_reset = _no_reset;
 156     have_old_t = false;
 157
 158     if (!lock.lock())
 159     {
 160         seterr(EBUSY);
 161         return;
 162     }
 163
 164     // note: if CLOCAL is not set on the modem, open will
 165     // block until a carrier detect.  Since we have to open the modem to
 166     // generate a carrier detect, we have a problem.  So we open the modem
 167     // nonblocking.  It would then be safe to switch to blocking mode,
 168     // but that is no longer recommended for WvStream.
 169     open(filename, O_RDWR|O_NONBLOCK|O_NOCTTY);
 170
 171     if (isok())
 172         setup_modem(rtscts);
 173 }
 174
 175
 176 WvModem::~WvModem()
 177 {
 178     close();
 179 }
 180
 181
 182 void WvModem::setup_modem(bool rtscts)
 183 {
 184     if (!isok()) return;
 185
 186     if (tcgetattr(getrfd(), &t) || tcgetattr(getrfd(), &old_t))
 187     {
 188         closing = true;
 189         seterr(errno);
 190         return;
 191     }
 192     have_old_t = true;
 193
 194     drain();
 195
 196 #if HAVE_LINUX_SERIAL_H
 197     struct serial_struct old_sinfo, sinfo;
 198     sinfo.reserved_char[0] = 0;
 199     if (ioctl(getrfd(), TIOCGSERIAL, &old_sinfo) < 0)
 200         log("Cannot get information for serial port.");
 201     else
 202     {
 203         sinfo = old_sinfo;
 204         // Why there are two closing wait timeouts, is beyond me
 205         // but there are... apparently the second one is deprecated
 206         // but why take a chance...
 207         sinfo.closing_wait = ASYNC_CLOSING_WAIT_NONE;
 208         sinfo.closing_wait2 = ASYNC_CLOSING_WAIT_NONE;
 209
 210         if (ioctl(getrfd(), TIOCSSERIAL, &sinfo) < 0)
 211             log("Cannot set information for serial port.");
 212     }
 213 #endif
 214
 215     // set up the terminal characteristics.
 216     // see "man tcsetattr" for more information about these options.
 217     t.c_iflag &= ~(BRKINT | ISTRIP | IUCLC | IXON | IXANY | IXOFF | IMAXBEL);
 218     t.c_iflag |= (IGNBRK | IGNPAR);
 219     t.c_oflag &= ~(OLCUC);
 220     t.c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
 221     t.c_cflag |= (CS8 | CREAD | HUPCL | CLOCAL);
 222     if(rtscts)
 223         t.c_cflag |= CRTSCTS;
 224     t.c_lflag &= ~(ISIG | XCASE | ECHO);
 225     tcsetattr(getrfd(), TCSANOW, &t);
 226
 227     // make sure we leave the modem in CLOCAL when we exit, so normal user
 228     // tasks can open the modem without using nonblocking.
 229     old_t.c_cflag |= CLOCAL;
 230
 231     // Send a few returns to make sure the modem is "good and zonked".
 232     if (cfgetospeed(&t) != B0 && !no_reset)
 233     {
 234         for(int i=0; i<5; i++)
 235         {
 236             write("\r", 1);
 237             usleep(10 * 1000);
 238         }
 239     }
 240
 241     // Set the baud rate to 0 for half a second to drop DTR...
 242     cfsetispeed(&t, B0);
 243     cfsetospeed(&t, B0);
 244     cfmakeraw(&t);
 245     tcsetattr(getrfd(), TCSANOW, &t);
 246     if (carrier())
 247         usleep(500 * 1000);
 248
 249     speed(baud);
 250     usleep(10 * 1000);
 251
 252     drain();
 253 }
 254
 255
 256 void WvModem::close()
 257 {
 258     if (!closed)
 259     {
 260         if (!closing)
 261         {
 262             closing = true;
 263             if (!no_reset)
 264                 hangup();
 265             else
 266             {
 267                 drain();
 268                 cfsetospeed(&t, B0);
 269                 // If this works??
 270                 write("\r");
 271             }
 272         }
 273
 274         closing = true;
 275         if (getrfd() >= 0)
 276         {
 277             tcflush(getrfd(), TCIOFLUSH);
 278             if (have_old_t)
 279                 tcsetattr(getrfd(), TCSANOW, &old_t);
 280             tcflush(getrfd(), TCIOFLUSH);
 281         }
 282         WvFile::close();
 283         closing = false;
 284     }
 285 }
 286
 287
 288 int WvModem::speed(int _baud)
 289 {
 290     speed_t s = B0;
 291     baud = 0;
 292     for (unsigned int i = 0; i < sizeof(speeds) / sizeof(*speeds); i++)
 293     {
 294         if (speeds[i].baud <= _baud)
 295         {
 296             s = speeds[i].speedt;
 297             break;
 298         }
 299     }
 300
 301     cfsetispeed(&t, B0); // auto-match to output speed
 302     cfsetospeed(&t, s);
 303     tcsetattr(getrfd(), TCSANOW, &t);
 304
 305     return get_real_speed();
 306 }
 307
 308
 309 int WvModem::getstatus()
 310 {
 311     if (!isok()) return 0;
 312     int status = 0;
 313     ioctl(getrfd(), TIOCMGET, &status);
 314     return status;
 315 }
 316
 317
 318 bool WvModem::carrier()
 319 {
 320     return (getstatus() & TIOCM_CD) ? 1 : 0;
 321 }