Commit | Line | Data |
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3eb25fda MM |
1 | /* Generic serial interface functions. |
2 | ||
0b302171 JB |
3 | Copyright (C) 1992-1996, 1998-2001, 2003-2012 Free Software |
4 | Foundation, Inc. | |
3eb25fda MM |
5 | |
6 | This file is part of GDB. | |
7 | ||
8 | This program is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 10 | the Free Software Foundation; either version 3 of the License, or |
3eb25fda MM |
11 | (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 General Public License | |
a9762ec7 | 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
3eb25fda MM |
20 | |
21 | #include "defs.h" | |
22 | #include "serial.h" | |
a07ff70c | 23 | #include "ser-base.h" |
3eb25fda | 24 | #include "event-loop.h" |
a07ff70c | 25 | |
0ea3f30e | 26 | #include "gdb_select.h" |
a07ff70c | 27 | #include "gdb_string.h" |
248697b2 | 28 | #include <sys/time.h> |
b4505029 MM |
29 | #ifdef USE_WIN32API |
30 | #include <winsock2.h> | |
31 | #endif | |
3eb25fda | 32 | |
401e7faf | 33 | |
3eb25fda MM |
34 | static timer_handler_func push_event; |
35 | static handler_func fd_event; | |
36 | ||
37 | /* Event handling for ASYNC serial code. | |
38 | ||
39 | At any time the SERIAL device either: has an empty FIFO and is | |
40 | waiting on a FD event; or has a non-empty FIFO/error condition and | |
41 | is constantly scheduling timer events. | |
42 | ||
43 | ASYNC only stops pestering its client when it is de-async'ed or it | |
c378eb4e | 44 | is told to go away. */ |
3eb25fda MM |
45 | |
46 | /* Value of scb->async_state: */ | |
47 | enum { | |
48 | /* >= 0 (TIMER_SCHEDULED) */ | |
c378eb4e | 49 | /* The ID of the currently scheduled timer event. This state is |
3eb25fda | 50 | rarely encountered. Timer events are one-off so as soon as the |
c378eb4e | 51 | event is delivered the state is shanged to NOTHING_SCHEDULED. */ |
3eb25fda MM |
52 | FD_SCHEDULED = -1, |
53 | /* The fd_event() handler is scheduled. It is called when ever the | |
c378eb4e | 54 | file descriptor becomes ready. */ |
3eb25fda MM |
55 | NOTHING_SCHEDULED = -2 |
56 | /* Either no task is scheduled (just going into ASYNC mode) or a | |
57 | timer event has just gone off and the current state has been | |
c378eb4e | 58 | forced into nothing scheduled. */ |
3eb25fda MM |
59 | }; |
60 | ||
61 | /* Identify and schedule the next ASYNC task based on scb->async_state | |
62 | and scb->buf* (the input FIFO). A state machine is used to avoid | |
63 | the need to make redundant calls into the event-loop - the next | |
c378eb4e | 64 | scheduled task is only changed when needed. */ |
3eb25fda | 65 | |
a26d8d11 | 66 | static void |
3eb25fda MM |
67 | reschedule (struct serial *scb) |
68 | { | |
69 | if (serial_is_async_p (scb)) | |
70 | { | |
71 | int next_state; | |
433759f7 | 72 | |
3eb25fda MM |
73 | switch (scb->async_state) |
74 | { | |
75 | case FD_SCHEDULED: | |
76 | if (scb->bufcnt == 0) | |
77 | next_state = FD_SCHEDULED; | |
78 | else | |
79 | { | |
80 | delete_file_handler (scb->fd); | |
81 | next_state = create_timer (0, push_event, scb); | |
82 | } | |
83 | break; | |
84 | case NOTHING_SCHEDULED: | |
85 | if (scb->bufcnt == 0) | |
86 | { | |
87 | add_file_handler (scb->fd, fd_event, scb); | |
88 | next_state = FD_SCHEDULED; | |
89 | } | |
90 | else | |
91 | { | |
92 | next_state = create_timer (0, push_event, scb); | |
93 | } | |
94 | break; | |
95 | default: /* TIMER SCHEDULED */ | |
96 | if (scb->bufcnt == 0) | |
97 | { | |
98 | delete_timer (scb->async_state); | |
99 | add_file_handler (scb->fd, fd_event, scb); | |
100 | next_state = FD_SCHEDULED; | |
101 | } | |
102 | else | |
103 | next_state = scb->async_state; | |
104 | break; | |
105 | } | |
106 | if (serial_debug_p (scb)) | |
107 | { | |
108 | switch (next_state) | |
109 | { | |
110 | case FD_SCHEDULED: | |
111 | if (scb->async_state != FD_SCHEDULED) | |
112 | fprintf_unfiltered (gdb_stdlog, "[fd%d->fd-scheduled]\n", | |
113 | scb->fd); | |
114 | break; | |
115 | default: /* TIMER SCHEDULED */ | |
116 | if (scb->async_state == FD_SCHEDULED) | |
117 | fprintf_unfiltered (gdb_stdlog, "[fd%d->timer-scheduled]\n", | |
118 | scb->fd); | |
119 | break; | |
120 | } | |
121 | } | |
122 | scb->async_state = next_state; | |
123 | } | |
124 | } | |
125 | ||
ddefb60f PA |
126 | /* Run the SCB's async handle, and reschedule, if the handler doesn't |
127 | close SCB. */ | |
128 | ||
129 | static void | |
130 | run_async_handler_and_reschedule (struct serial *scb) | |
131 | { | |
132 | int is_open; | |
133 | ||
134 | /* Take a reference, so a serial_close call within the handler | |
135 | doesn't make SCB a dangling pointer. */ | |
136 | serial_ref (scb); | |
137 | ||
138 | /* Run the handler. */ | |
139 | scb->async_handler (scb, scb->async_context); | |
140 | ||
141 | is_open = serial_is_open (scb); | |
142 | serial_unref (scb); | |
143 | ||
144 | /* Get ready for more, if not already closed. */ | |
145 | if (is_open) | |
146 | reschedule (scb); | |
147 | } | |
148 | ||
3eb25fda MM |
149 | /* FD_EVENT: This is scheduled when the input FIFO is empty (and there |
150 | is no pending error). As soon as data arrives, it is read into the | |
151 | input FIFO and the client notified. The client should then drain | |
152 | the FIFO using readchar(). If the FIFO isn't immediatly emptied, | |
c378eb4e | 153 | push_event() is used to nag the client until it is. */ |
3eb25fda MM |
154 | |
155 | static void | |
156 | fd_event (int error, void *context) | |
157 | { | |
158 | struct serial *scb = context; | |
159 | if (error != 0) | |
160 | { | |
161 | scb->bufcnt = SERIAL_ERROR; | |
162 | } | |
163 | else if (scb->bufcnt == 0) | |
164 | { | |
165 | /* Prime the input FIFO. The readchar() function is used to | |
166 | pull characters out of the buffer. See also | |
c378eb4e | 167 | generic_readchar(). */ |
3eb25fda | 168 | int nr; |
b4505029 | 169 | nr = scb->ops->read_prim (scb, BUFSIZ); |
3eb25fda MM |
170 | if (nr == 0) |
171 | { | |
172 | scb->bufcnt = SERIAL_EOF; | |
173 | } | |
174 | else if (nr > 0) | |
175 | { | |
176 | scb->bufcnt = nr; | |
177 | scb->bufp = scb->buf; | |
178 | } | |
179 | else | |
180 | { | |
181 | scb->bufcnt = SERIAL_ERROR; | |
182 | } | |
183 | } | |
ddefb60f | 184 | run_async_handler_and_reschedule (scb); |
3eb25fda MM |
185 | } |
186 | ||
187 | /* PUSH_EVENT: The input FIFO is non-empty (or there is a pending | |
188 | error). Nag the client until all the data has been read. In the | |
189 | case of errors, the client will need to close or de-async the | |
c378eb4e | 190 | device before naging stops. */ |
3eb25fda MM |
191 | |
192 | static void | |
193 | push_event (void *context) | |
194 | { | |
195 | struct serial *scb = context; | |
433759f7 | 196 | |
3eb25fda | 197 | scb->async_state = NOTHING_SCHEDULED; /* Timers are one-off */ |
ddefb60f | 198 | run_async_handler_and_reschedule (scb); |
3eb25fda MM |
199 | } |
200 | ||
b4505029 | 201 | /* Wait for input on scb, with timeout seconds. Returns 0 on success, |
c378eb4e | 202 | otherwise SERIAL_TIMEOUT or SERIAL_ERROR. */ |
b4505029 MM |
203 | |
204 | static int | |
205 | ser_base_wait_for (struct serial *scb, int timeout) | |
206 | { | |
207 | while (1) | |
208 | { | |
209 | int numfds; | |
210 | struct timeval tv; | |
211 | fd_set readfds, exceptfds; | |
212 | ||
213 | /* NOTE: Some OS's can scramble the READFDS when the select() | |
214 | call fails (ex the kernel with Red Hat 5.2). Initialize all | |
c378eb4e | 215 | arguments before each call. */ |
b4505029 MM |
216 | |
217 | tv.tv_sec = timeout; | |
218 | tv.tv_usec = 0; | |
219 | ||
220 | FD_ZERO (&readfds); | |
221 | FD_ZERO (&exceptfds); | |
222 | FD_SET (scb->fd, &readfds); | |
223 | FD_SET (scb->fd, &exceptfds); | |
224 | ||
225 | if (timeout >= 0) | |
0ea3f30e | 226 | numfds = gdb_select (scb->fd + 1, &readfds, 0, &exceptfds, &tv); |
b4505029 | 227 | else |
0ea3f30e | 228 | numfds = gdb_select (scb->fd + 1, &readfds, 0, &exceptfds, 0); |
b4505029 MM |
229 | |
230 | if (numfds <= 0) | |
231 | { | |
232 | if (numfds == 0) | |
233 | return SERIAL_TIMEOUT; | |
234 | else if (errno == EINTR) | |
235 | continue; | |
236 | else | |
c378eb4e MS |
237 | return SERIAL_ERROR; /* Got an error from select or |
238 | poll. */ | |
b4505029 MM |
239 | } |
240 | ||
241 | return 0; | |
242 | } | |
243 | } | |
244 | ||
245 | /* Read a character with user-specified timeout. TIMEOUT is number of seconds | |
246 | to wait, or -1 to wait forever. Use timeout of 0 to effect a poll. Returns | |
247 | char if successful. Returns -2 if timeout expired, EOF if line dropped | |
c378eb4e | 248 | dead, or -3 for any other error (see errno in that case). */ |
b4505029 MM |
249 | |
250 | static int | |
251 | do_ser_base_readchar (struct serial *scb, int timeout) | |
252 | { | |
253 | int status; | |
254 | int delta; | |
255 | ||
256 | /* We have to be able to keep the GUI alive here, so we break the | |
257 | original timeout into steps of 1 second, running the "keep the | |
258 | GUI alive" hook each time through the loop. | |
259 | ||
260 | Also, timeout = 0 means to poll, so we just set the delta to 0, | |
261 | so we will only go through the loop once. */ | |
262 | ||
263 | delta = (timeout == 0 ? 0 : 1); | |
264 | while (1) | |
265 | { | |
266 | /* N.B. The UI may destroy our world (for instance by calling | |
267 | remote_stop,) in which case we want to get out of here as | |
268 | quickly as possible. It is not safe to touch scb, since | |
269 | someone else might have freed it. The | |
270 | deprecated_ui_loop_hook signals that we should exit by | |
271 | returning 1. */ | |
272 | ||
273 | if (deprecated_ui_loop_hook) | |
274 | { | |
275 | if (deprecated_ui_loop_hook (0)) | |
276 | return SERIAL_TIMEOUT; | |
277 | } | |
278 | ||
279 | status = ser_base_wait_for (scb, delta); | |
280 | if (timeout > 0) | |
281 | timeout -= delta; | |
282 | ||
283 | /* If we got a character or an error back from wait_for, then we can | |
c378eb4e | 284 | break from the loop before the timeout is completed. */ |
b4505029 MM |
285 | if (status != SERIAL_TIMEOUT) |
286 | break; | |
287 | ||
288 | /* If we have exhausted the original timeout, then generate | |
c378eb4e | 289 | a SERIAL_TIMEOUT, and pass it out of the loop. */ |
b4505029 MM |
290 | else if (timeout == 0) |
291 | { | |
292 | status = SERIAL_TIMEOUT; | |
293 | break; | |
294 | } | |
295 | } | |
296 | ||
297 | if (status < 0) | |
298 | return status; | |
299 | ||
300 | status = scb->ops->read_prim (scb, BUFSIZ); | |
301 | ||
302 | if (status <= 0) | |
303 | { | |
304 | if (status == 0) | |
d41ebd5d | 305 | return SERIAL_EOF; |
b4505029 MM |
306 | else |
307 | /* Got an error from read. */ | |
308 | return SERIAL_ERROR; | |
309 | } | |
310 | ||
311 | scb->bufcnt = status; | |
312 | scb->bufcnt--; | |
313 | scb->bufp = scb->buf; | |
314 | return *scb->bufp++; | |
315 | } | |
316 | ||
c378eb4e | 317 | /* Perform operations common to both old and new readchar. */ |
b4505029 MM |
318 | |
319 | /* Return the next character from the input FIFO. If the FIFO is | |
320 | empty, call the SERIAL specific routine to try and read in more | |
321 | characters. | |
322 | ||
323 | Initially data from the input FIFO is returned (fd_event() | |
324 | pre-reads the input into that FIFO. Once that has been emptied, | |
325 | further data is obtained by polling the input FD using the device | |
326 | specific readchar() function. Note: reschedule() is called after | |
327 | every read. This is because there is no guarentee that the lower | |
328 | level fd_event() poll_event() code (which also calls reschedule()) | |
c378eb4e | 329 | will be called. */ |
b4505029 MM |
330 | |
331 | int | |
332 | generic_readchar (struct serial *scb, int timeout, | |
333 | int (do_readchar) (struct serial *scb, int timeout)) | |
334 | { | |
335 | int ch; | |
336 | if (scb->bufcnt > 0) | |
337 | { | |
338 | ch = *scb->bufp; | |
339 | scb->bufcnt--; | |
340 | scb->bufp++; | |
341 | } | |
342 | else if (scb->bufcnt < 0) | |
343 | { | |
c378eb4e | 344 | /* Some errors/eof are are sticky. */ |
b4505029 MM |
345 | ch = scb->bufcnt; |
346 | } | |
347 | else | |
348 | { | |
349 | ch = do_readchar (scb, timeout); | |
350 | if (ch < 0) | |
351 | { | |
352 | switch ((enum serial_rc) ch) | |
353 | { | |
354 | case SERIAL_EOF: | |
355 | case SERIAL_ERROR: | |
c378eb4e | 356 | /* Make the error/eof stick. */ |
b4505029 MM |
357 | scb->bufcnt = ch; |
358 | break; | |
359 | case SERIAL_TIMEOUT: | |
360 | scb->bufcnt = 0; | |
361 | break; | |
362 | } | |
363 | } | |
364 | } | |
65cc4390 VP |
365 | /* Read any error output we might have. */ |
366 | if (scb->error_fd != -1) | |
367 | { | |
368 | ssize_t s; | |
369 | char buf[81]; | |
370 | ||
371 | for (;;) | |
372 | { | |
373 | char *current; | |
374 | char *newline; | |
375 | int to_read = 80; | |
376 | ||
377 | int num_bytes = -1; | |
378 | if (scb->ops->avail) | |
379 | num_bytes = (scb->ops->avail)(scb, scb->error_fd); | |
380 | if (num_bytes != -1) | |
381 | to_read = (num_bytes < to_read) ? num_bytes : to_read; | |
382 | ||
383 | if (to_read == 0) | |
384 | break; | |
385 | ||
386 | s = read (scb->error_fd, &buf, to_read); | |
9f117f47 | 387 | if (s == -1) |
65cc4390 | 388 | break; |
9f117f47 DE |
389 | if (s == 0) |
390 | { | |
391 | /* EOF */ | |
392 | close (scb->error_fd); | |
393 | scb->error_fd = -1; | |
394 | break; | |
395 | } | |
65cc4390 VP |
396 | |
397 | /* In theory, embedded newlines are not a problem. | |
398 | But for MI, we want each output line to have just | |
399 | one newline for legibility. So output things | |
400 | in newline chunks. */ | |
401 | buf[s] = '\0'; | |
402 | current = buf; | |
403 | while ((newline = strstr (current, "\n")) != NULL) | |
404 | { | |
405 | *newline = '\0'; | |
406 | fputs_unfiltered (current, gdb_stderr); | |
407 | fputs_unfiltered ("\n", gdb_stderr); | |
408 | current = newline + 1; | |
409 | } | |
410 | fputs_unfiltered (current, gdb_stderr); | |
411 | } | |
412 | } | |
413 | ||
b4505029 MM |
414 | reschedule (scb); |
415 | return ch; | |
416 | } | |
417 | ||
418 | int | |
419 | ser_base_readchar (struct serial *scb, int timeout) | |
420 | { | |
421 | return generic_readchar (scb, timeout, do_ser_base_readchar); | |
422 | } | |
423 | ||
3eb25fda | 424 | int |
dd5da072 | 425 | ser_base_write (struct serial *scb, const char *str, int len) |
3eb25fda MM |
426 | { |
427 | int cc; | |
428 | ||
429 | while (len > 0) | |
430 | { | |
b4505029 | 431 | cc = scb->ops->write_prim (scb, str, len); |
3eb25fda MM |
432 | |
433 | if (cc < 0) | |
434 | return 1; | |
435 | len -= cc; | |
436 | str += cc; | |
437 | } | |
438 | return 0; | |
439 | } | |
440 | ||
441 | int | |
dd5da072 | 442 | ser_base_flush_output (struct serial *scb) |
3eb25fda MM |
443 | { |
444 | return 0; | |
445 | } | |
446 | ||
447 | int | |
dd5da072 | 448 | ser_base_flush_input (struct serial *scb) |
3eb25fda MM |
449 | { |
450 | if (scb->bufcnt >= 0) | |
451 | { | |
452 | scb->bufcnt = 0; | |
453 | scb->bufp = scb->buf; | |
454 | return 0; | |
455 | } | |
456 | else | |
457 | return SERIAL_ERROR; | |
458 | } | |
459 | ||
460 | int | |
dd5da072 | 461 | ser_base_send_break (struct serial *scb) |
3eb25fda MM |
462 | { |
463 | return 0; | |
464 | } | |
465 | ||
466 | int | |
dd5da072 | 467 | ser_base_drain_output (struct serial *scb) |
3eb25fda MM |
468 | { |
469 | return 0; | |
470 | } | |
471 | ||
472 | void | |
dd5da072 | 473 | ser_base_raw (struct serial *scb) |
3eb25fda | 474 | { |
c378eb4e | 475 | return; /* Always in raw mode. */ |
3eb25fda MM |
476 | } |
477 | ||
478 | serial_ttystate | |
dd5da072 | 479 | ser_base_get_tty_state (struct serial *scb) |
3eb25fda | 480 | { |
c378eb4e | 481 | /* Allocate a dummy. */ |
3eb25fda MM |
482 | return (serial_ttystate) XMALLOC (int); |
483 | } | |
484 | ||
1e182ce8 UW |
485 | serial_ttystate |
486 | ser_base_copy_tty_state (struct serial *scb, serial_ttystate ttystate) | |
487 | { | |
488 | /* Allocate another dummy. */ | |
489 | return (serial_ttystate) XMALLOC (int); | |
490 | } | |
491 | ||
3eb25fda | 492 | int |
dd5da072 | 493 | ser_base_set_tty_state (struct serial *scb, serial_ttystate ttystate) |
3eb25fda MM |
494 | { |
495 | return 0; | |
496 | } | |
497 | ||
498 | int | |
dd5da072 MM |
499 | ser_base_noflush_set_tty_state (struct serial *scb, |
500 | serial_ttystate new_ttystate, | |
501 | serial_ttystate old_ttystate) | |
3eb25fda MM |
502 | { |
503 | return 0; | |
504 | } | |
505 | ||
506 | void | |
dd5da072 MM |
507 | ser_base_print_tty_state (struct serial *scb, |
508 | serial_ttystate ttystate, | |
509 | struct ui_file *stream) | |
3eb25fda MM |
510 | { |
511 | /* Nothing to print. */ | |
512 | return; | |
513 | } | |
514 | ||
515 | int | |
dd5da072 | 516 | ser_base_setbaudrate (struct serial *scb, int rate) |
3eb25fda | 517 | { |
c378eb4e | 518 | return 0; /* Never fails! */ |
3eb25fda MM |
519 | } |
520 | ||
521 | int | |
dd5da072 | 522 | ser_base_setstopbits (struct serial *scb, int num) |
3eb25fda | 523 | { |
c378eb4e | 524 | return 0; /* Never fails! */ |
3eb25fda MM |
525 | } |
526 | ||
527 | /* Put the SERIAL device into/out-of ASYNC mode. */ | |
528 | ||
529 | void | |
dd5da072 | 530 | ser_base_async (struct serial *scb, |
3eb25fda MM |
531 | int async_p) |
532 | { | |
533 | if (async_p) | |
534 | { | |
c378eb4e | 535 | /* Force a re-schedule. */ |
3eb25fda MM |
536 | scb->async_state = NOTHING_SCHEDULED; |
537 | if (serial_debug_p (scb)) | |
538 | fprintf_unfiltered (gdb_stdlog, "[fd%d->asynchronous]\n", | |
539 | scb->fd); | |
540 | reschedule (scb); | |
541 | } | |
542 | else | |
543 | { | |
544 | if (serial_debug_p (scb)) | |
545 | fprintf_unfiltered (gdb_stdlog, "[fd%d->synchronous]\n", | |
546 | scb->fd); | |
c378eb4e | 547 | /* De-schedule whatever tasks are currently scheduled. */ |
3eb25fda MM |
548 | switch (scb->async_state) |
549 | { | |
550 | case FD_SCHEDULED: | |
551 | delete_file_handler (scb->fd); | |
552 | break; | |
553 | case NOTHING_SCHEDULED: | |
554 | break; | |
555 | default: /* TIMER SCHEDULED */ | |
556 | delete_timer (scb->async_state); | |
557 | break; | |
558 | } | |
559 | } | |
560 | } |