463f4c43f7952d25a1bf29da5d7ab5f09fa1fc6a
2 * Serial back end (Unix-specific).
18 #define SERIAL_MAX_BACKLOG 4096
20 typedef struct serial_backend_data
{
29 * We store our serial backends in a tree sorted by fd, so that
30 * when we get an uxsel notification we know which backend instance
31 * is the owner of the serial port that caused it.
33 static int serial_compare_by_fd(void *av
, void *bv
)
35 Serial a
= (Serial
)av
;
36 Serial b
= (Serial
)bv
;
40 else if (a
->fd
> b
->fd
)
45 static int serial_find_by_fd(void *av
, void *bv
)
48 Serial b
= (Serial
)bv
;
57 static tree234
*serial_by_fd
= NULL
;
59 static int serial_select_result(int fd
, int event
);
60 static void serial_uxsel_setup(Serial serial
);
61 static void serial_try_write(Serial serial
);
63 static const char *serial_configure(Serial serial
, Config
*cfg
)
65 struct termios options
;
71 return "Unable to reconfigure already-closed serial connection";
73 tcgetattr(serial
->fd
, &options
);
76 * Find the appropriate baud rate flag.
78 #define SETBAUD(x) (bflag = B ## x, bval = x)
79 #define CHECKBAUD(x) do { if (cfg->serspeed >= x) SETBAUD(x); } while (0)
137 cfsetispeed(&options
, bflag
);
138 cfsetospeed(&options
, bflag
);
139 msg
= dupprintf("Configuring baud rate %d", bval
);
140 logevent(serial
->frontend
, msg
);
143 options
.c_cflag
&= ~CSIZE
;
144 switch (cfg
->serdatabits
) {
145 case 5: options
.c_cflag
|= CS5
; break;
146 case 6: options
.c_cflag
|= CS6
; break;
147 case 7: options
.c_cflag
|= CS7
; break;
148 case 8: options
.c_cflag
|= CS8
; break;
149 default: return "Invalid number of data bits (need 5, 6, 7 or 8)";
151 msg
= dupprintf("Configuring %d data bits", cfg
->serdatabits
);
152 logevent(serial
->frontend
, msg
);
155 if (cfg
->serstopbits
>= 4) {
156 options
.c_cflag
|= CSTOPB
;
158 options
.c_cflag
&= ~CSTOPB
;
160 msg
= dupprintf("Configuring %d stop bits",
161 (options
.c_cflag
& CSTOPB ?
2 : 1));
162 logevent(serial
->frontend
, msg
);
165 options
.c_iflag
&= ~(IXON
|IXOFF
);
167 options
.c_cflag
&= ~CRTSCTS
;
170 options
.c_cflag
&= ~CNEW_RTSCTS
;
172 if (cfg
->serflow
== SER_FLOW_XONXOFF
) {
173 options
.c_iflag
|= IXON
| IXOFF
;
175 } else if (cfg
->serflow
== SER_FLOW_RTSCTS
) {
177 options
.c_cflag
|= CRTSCTS
;
180 options
.c_cflag
|= CNEW_RTSCTS
;
185 msg
= dupprintf("Configuring %s flow control", str
);
186 logevent(serial
->frontend
, msg
);
190 if (cfg
->serparity
== SER_PAR_ODD
) {
191 options
.c_cflag
|= PARENB
;
192 options
.c_cflag
|= PARODD
;
194 } else if (cfg
->serparity
== SER_PAR_EVEN
) {
195 options
.c_cflag
|= PARENB
;
196 options
.c_cflag
&= ~PARODD
;
199 options
.c_cflag
&= ~PARENB
;
202 msg
= dupprintf("Configuring %s parity", str
);
203 logevent(serial
->frontend
, msg
);
206 options
.c_cflag
|= CLOCAL
| CREAD
;
207 options
.c_lflag
&= ~(ICANON
| ECHO
| ECHOE
| ISIG
);
208 options
.c_oflag
&= ~OPOST
;
209 options
.c_cc
[VMIN
] = 1;
210 options
.c_cc
[VTIME
] = 0;
212 if (tcsetattr(serial
->fd
, TCSANOW
, &options
) < 0)
213 return "Unable to configure serial port";
219 * Called to set up the serial connection.
221 * Returns an error message, or NULL on success.
223 * Also places the canonical host name into `realhost'. It must be
224 * freed by the caller.
226 static const char *serial_init(void *frontend_handle
, void **backend_handle
,
228 char *host
, int port
, char **realhost
, int nodelay
,
234 serial
= snew(struct serial_backend_data
);
235 *backend_handle
= serial
;
237 serial
->frontend
= frontend_handle
;
238 serial
->finished
= FALSE
;
239 serial
->inbufsize
= 0;
240 bufchain_init(&serial
->output_data
);
243 char *msg
= dupprintf("Opening serial device %s", cfg
->serline
);
244 logevent(serial
->frontend
, msg
);
247 serial
->fd
= open(cfg
->serline
, O_RDWR
| O_NOCTTY
| O_NDELAY
| O_NONBLOCK
);
249 return "Unable to open serial port";
251 err
= serial_configure(serial
, cfg
);
255 *realhost
= dupstr(cfg
->serline
);
258 serial_by_fd
= newtree234(serial_compare_by_fd
);
259 add234(serial_by_fd
, serial
);
261 serial_uxsel_setup(serial
);
264 * Specials are always available.
266 update_specials_menu(serial
->frontend
);
271 static void serial_close(Serial serial
)
273 if (serial
->fd
>= 0) {
279 static void serial_free(void *handle
)
281 Serial serial
= (Serial
) handle
;
283 serial_close(serial
);
285 bufchain_clear(&serial
->output_data
);
290 static void serial_reconfig(void *handle
, Config
*cfg
)
292 Serial serial
= (Serial
) handle
;
295 err
= serial_configure(serial
, cfg
);
298 * FIXME: what should we do if err returns something?
302 static int serial_select_result(int fd
, int event
)
307 int finished
= FALSE
;
309 serial
= find234(serial_by_fd
, &fd
, serial_find_by_fd
);
312 return 1; /* spurious event; keep going */
315 ret
= read(serial
->fd
, buf
, sizeof(buf
));
319 * Shouldn't happen on a real serial port, but I'm open
320 * to the idea that there might be two-way devices we
321 * can treat _like_ serial ports which can return EOF.
324 } else if (ret
< 0) {
325 perror("read serial port");
327 } else if (ret
> 0) {
328 serial
->inbufsize
= from_backend(serial
->frontend
, 0, buf
, ret
);
329 serial_uxsel_setup(serial
); /* might acquire backlog and freeze */
331 } else if (event
== 2) {
333 * Attempt to send data down the pty.
335 serial_try_write(serial
);
339 serial_close(serial
);
341 serial
->finished
= TRUE
;
343 notify_remote_exit(serial
->frontend
);
349 static void serial_uxsel_setup(Serial serial
)
353 if (serial
->inbufsize
<= SERIAL_MAX_BACKLOG
)
355 if (bufchain_size(&serial
->output_data
))
356 rwx
|= 2; /* might also want to write to it */
357 uxsel_set(serial
->fd
, rwx
, serial_select_result
);
360 static void serial_try_write(Serial serial
)
365 assert(serial
->fd
>= 0);
367 while (bufchain_size(&serial
->output_data
) > 0) {
368 bufchain_prefix(&serial
->output_data
, &data
, &len
);
369 ret
= write(serial
->fd
, data
, len
);
371 if (ret
< 0 && (errno
== EWOULDBLOCK
)) {
373 * We've sent all we can for the moment.
378 perror("write serial port");
381 bufchain_consume(&serial
->output_data
, ret
);
384 serial_uxsel_setup(serial
);
388 * Called to send data down the serial connection.
390 static int serial_send(void *handle
, char *buf
, int len
)
392 Serial serial
= (Serial
) handle
;
397 bufchain_add(&serial
->output_data
, buf
, len
);
398 serial_try_write(serial
);
400 return bufchain_size(&serial
->output_data
);
404 * Called to query the current sendability status.
406 static int serial_sendbuffer(void *handle
)
408 Serial serial
= (Serial
) handle
;
409 return bufchain_size(&serial
->output_data
);
413 * Called to set the size of the window
415 static void serial_size(void *handle
, int width
, int height
)
422 * Send serial special codes.
424 static void serial_special(void *handle
, Telnet_Special code
)
426 Serial serial
= (Serial
) handle
;
428 if (serial
->fd
>= 0 && code
== TS_BRK
) {
429 tcsendbreak(serial
->fd
, 0);
430 logevent(serial
->frontend
, "Sending serial break at user request");
437 * Return a list of the special codes that make sense in this
440 static const struct telnet_special
*serial_get_specials(void *handle
)
442 static const struct telnet_special specials
[] = {
449 static int serial_connected(void *handle
)
451 return 1; /* always connected */
454 static int serial_sendok(void *handle
)
459 static void serial_unthrottle(void *handle
, int backlog
)
461 Serial serial
= (Serial
) handle
;
462 serial
->inbufsize
= backlog
;
463 serial_uxsel_setup(serial
);
466 static int serial_ldisc(void *handle
, int option
)
469 * Local editing and local echo are off by default.
474 static void serial_provide_ldisc(void *handle
, void *ldisc
)
476 /* This is a stub. */
479 static void serial_provide_logctx(void *handle
, void *logctx
)
481 /* This is a stub. */
484 static int serial_exitcode(void *handle
)
486 Serial serial
= (Serial
) handle
;
488 return -1; /* still connected */
490 /* Exit codes are a meaningless concept with serial ports */
495 * cfg_info for Serial does nothing at all.
497 static int serial_cfg_info(void *handle
)
502 Backend serial_backend
= {
515 serial_provide_ldisc
,
516 serial_provide_logctx
,