FreeBSD/Linux Kernel Cross Reference
sys/gdb/gdb_main.c
1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2004 Marcel Moolenaar
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kdb.h>
35 #include <sys/kernel.h>
36 #include <sys/pcpu.h>
37 #include <sys/proc.h>
38 #include <sys/reboot.h>
39 #include <sys/sbuf.h>
40
41 #include <machine/gdb_machdep.h>
42 #include <machine/kdb.h>
43
44 #include <gdb/gdb.h>
45 #include <gdb/gdb_int.h>
46
47 SYSCTL_NODE(_debug, OID_AUTO, gdb, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
48 "GDB settings");
49
50 static dbbe_init_f gdb_init;
51 static dbbe_trap_f gdb_trap;
52
53 KDB_BACKEND(gdb, gdb_init, NULL, NULL, gdb_trap);
54
55 static struct gdb_dbgport null_gdb_dbgport;
56 DATA_SET(gdb_dbgport_set, null_gdb_dbgport);
57 SET_DECLARE(gdb_dbgport_set, struct gdb_dbgport);
58
59 struct gdb_dbgport *gdb_cur = NULL;
60 int gdb_listening = 0;
61 bool gdb_ackmode = true;
62
63 static unsigned char gdb_bindata[64];
64
65 #ifdef DDB
66 bool gdb_return_to_ddb = false;
67 #endif
68
69 static int
70 gdb_init(void)
71 {
72 struct gdb_dbgport *dp, **iter;
73 int cur_pri, pri;
74
75 gdb_cur = NULL;
76 cur_pri = -1;
77 SET_FOREACH(iter, gdb_dbgport_set) {
78 dp = *iter;
79 pri = (dp->gdb_probe != NULL) ? dp->gdb_probe() : -1;
80 dp->gdb_active = (pri >= 0) ? 0 : -1;
81 if (pri > cur_pri) {
82 cur_pri = pri;
83 gdb_cur = dp;
84 }
85 }
86 if (gdb_cur != NULL) {
87 printf("GDB: debug ports:");
88 SET_FOREACH(iter, gdb_dbgport_set) {
89 dp = *iter;
90 if (dp->gdb_active == 0)
91 printf(" %s", dp->gdb_name);
92 }
93 printf("\n");
94 } else
95 printf("GDB: no debug ports present\n");
96 if (gdb_cur != NULL) {
97 gdb_cur->gdb_init();
98 printf("GDB: current port: %s\n", gdb_cur->gdb_name);
99 }
100 if (gdb_cur != NULL) {
101 cur_pri = (boothowto & RB_GDB) ? 2 : 0;
102 gdb_consinit();
103 } else
104 cur_pri = -1;
105 return (cur_pri);
106 }
107
108 static void
109 gdb_do_mem_search(void)
110 {
111 size_t patlen;
112 intmax_t addr, size;
113 const unsigned char *found;
114
115 if (gdb_rx_varhex(&addr) || gdb_rx_char() != ';' ||
116 gdb_rx_varhex(&size) || gdb_rx_char() != ';' ||
117 gdb_rx_bindata(gdb_bindata, sizeof(gdb_bindata), &patlen)) {
118 gdb_tx_err(EINVAL);
119 return;
120 }
121 if (gdb_search_mem((char *)(uintptr_t)addr, size, gdb_bindata,
122 patlen, &found)) {
123 if (found == 0ULL)
124 gdb_tx_begin('');
125 else {
126 gdb_tx_begin('1');
127 gdb_tx_char(',');
128 gdb_tx_hex((intmax_t)(uintptr_t)found, 8);
129 }
130 gdb_tx_end();
131 } else
132 gdb_tx_err(EIO);
133 }
134
135 static void
136 gdb_do_threadinfo(struct thread **thr_iter)
137 {
138 static struct thread * const done_sentinel = (void *)(uintptr_t)1;
139 static const size_t tidsz_hex = sizeof(lwpid_t) * 2;
140 size_t tds_sent;
141
142 if (*thr_iter == NULL) {
143 gdb_tx_err(ENXIO);
144 return;
145 }
146
147 if (*thr_iter == done_sentinel) {
148 gdb_tx_begin('l');
149 *thr_iter = NULL;
150 goto sendit;
151 }
152
153 gdb_tx_begin('m');
154
155 for (tds_sent = 0;
156 *thr_iter != NULL && gdb_txbuf_has_capacity(tidsz_hex + 1);
157 *thr_iter = kdb_thr_next(*thr_iter), tds_sent++) {
158 if (tds_sent > 0)
159 gdb_tx_char(',');
160 gdb_tx_varhex((*thr_iter)->td_tid);
161 }
162
163 /*
164 * Can't send EOF and "some" in same packet, so set a sentinel to send
165 * EOF when GDB asks us next.
166 */
167 if (*thr_iter == NULL && tds_sent > 0)
168 *thr_iter = done_sentinel;
169
170 sendit:
171 gdb_tx_end();
172 }
173
174 #define BIT(n) (1ull << (n))
175 enum {
176 GDB_MULTIPROCESS,
177 GDB_SWBREAK,
178 GDB_HWBREAK,
179 GDB_QRELOCINSN,
180 GDB_FORK_EVENTS,
181 GDB_VFORK_EVENTS,
182 GDB_EXEC_EVENTS,
183 GDB_VCONT_SUPPORTED,
184 GDB_QTHREADEVENTS,
185 GDB_NO_RESUMED,
186 };
187 static const char * const gdb_feature_names[] = {
188 [GDB_MULTIPROCESS] = "multiprocess",
189 [GDB_SWBREAK] = "swbreak",
190 [GDB_HWBREAK] = "hwbreak",
191 [GDB_QRELOCINSN] = "qRelocInsn",
192 [GDB_FORK_EVENTS] = "fork-events",
193 [GDB_VFORK_EVENTS] = "vfork-events",
194 [GDB_EXEC_EVENTS] = "exec-events",
195 [GDB_VCONT_SUPPORTED] = "vContSupported",
196 [GDB_QTHREADEVENTS] = "QThreadEvents",
197 [GDB_NO_RESUMED] = "no-resumed",
198 };
199 static void
200 gdb_do_qsupported(uint32_t *feat)
201 {
202 char *tok, *delim, ok;
203 size_t i, toklen;
204
205 /* Parse supported host features */
206 *feat = 0;
207 switch (gdb_rx_char()) {
208 case ':':
209 break;
210 case EOF:
211 goto nofeatures;
212 default:
213 goto error;
214 }
215
216 while (gdb_rxsz > 0) {
217 tok = gdb_rxp;
218 delim = strchrnul(gdb_rxp, ';');
219 toklen = (delim - tok);
220
221 gdb_rxp += toklen;
222 gdb_rxsz -= toklen;
223 if (*delim != '\0') {
224 *delim = '\0';
225 gdb_rxp += 1;
226 gdb_rxsz -= 1;
227 }
228
229 if (toklen < 2)
230 goto error;
231
232 ok = tok[toklen - 1];
233 if (ok != '-' && ok != '+') {
234 /*
235 * GDB only has one KV-pair feature, and we don't
236 * support it, so ignore and move on.
237 */
238 if (strchr(tok, '=') != NULL)
239 continue;
240 /* Not a KV-pair, and not a +/- flag? Malformed. */
241 goto error;
242 }
243 if (ok != '+')
244 continue;
245 tok[toklen - 1] = '\0';
246
247 for (i = 0; i < nitems(gdb_feature_names); i++)
248 if (strcmp(gdb_feature_names[i], tok) == 0)
249 break;
250
251 if (i == nitems(gdb_feature_names)) {
252 /* Unknown GDB feature. */
253 continue;
254 }
255
256 *feat |= BIT(i);
257 }
258
259 nofeatures:
260 /* Send a supported feature list back */
261 gdb_tx_begin(0);
262
263 gdb_tx_str("PacketSize");
264 gdb_tx_char('=');
265 /*
266 * We don't buffer framing bytes, but we do need to retain a byte for a
267 * trailing nul.
268 */
269 gdb_tx_varhex(GDB_BUFSZ + strlen("$#nn") - 1);
270
271 gdb_tx_str(";qXfer:threads:read+");
272
273 /*
274 * If the debugport is a reliable transport, request No Ack mode from
275 * the server. The server may or may not choose to enter No Ack mode.
276 * https://sourceware.org/gdb/onlinedocs/gdb/Packet-Acknowledgment.html
277 */
278 if (gdb_cur->gdb_dbfeatures & GDB_DBGP_FEAT_RELIABLE)
279 gdb_tx_str(";QStartNoAckMode+");
280
281 /*
282 * Future consideration:
283 * - vCont
284 * - multiprocess
285 */
286 gdb_tx_end();
287 return;
288
289 error:
290 *feat = 0;
291 gdb_tx_err(EINVAL);
292 }
293
294 /*
295 * A qXfer_context provides a vaguely generic way to generate a multi-packet
296 * response on the fly, making some assumptions about the size of sbuf writes
297 * vs actual packet length constraints. A non-byzantine gdb host should allow
298 * hundreds of bytes per packet or more.
299 *
300 * Upper layers are considered responsible for escaping the four forbidden
301 * characters '# $ } *'.
302 */
303 struct qXfer_context {
304 struct sbuf sb;
305 size_t last_offset;
306 bool flushed;
307 bool lastmessage;
308 char xfer_buf[GDB_BUFSZ];
309 };
310
311 static int
312 qXfer_drain(void *v, const char *buf, int len)
313 {
314 struct qXfer_context *qx;
315
316 if (len < 0)
317 return (-EINVAL);
318
319 qx = v;
320 if (qx->flushed) {
321 /*
322 * Overflow. We lost some message. Maybe the packet size is
323 * ridiculously small.
324 */
325 printf("%s: Overflow in qXfer detected.\n", __func__);
326 return (-ENOBUFS);
327 }
328
329 qx->last_offset += len;
330 qx->flushed = true;
331
332 if (qx->lastmessage)
333 gdb_tx_begin('l');
334 else
335 gdb_tx_begin('m');
336
337 memcpy(gdb_txp, buf, len);
338 gdb_txp += len;
339
340 gdb_tx_end();
341 return (len);
342 }
343
344 static int
345 init_qXfer_ctx(struct qXfer_context *qx, uintmax_t len)
346 {
347
348 /* Protocol (max) length field includes framing overhead. */
349 if (len < sizeof("$m#nn"))
350 return (ENOSPC);
351
352 len -= 4;
353 len = ummin(len, GDB_BUFSZ - 1);
354
355 qx->last_offset = 0;
356 qx->flushed = false;
357 qx->lastmessage = false;
358 sbuf_new(&qx->sb, qx->xfer_buf, len, SBUF_FIXEDLEN);
359 sbuf_set_drain(&qx->sb, qXfer_drain, qx);
360 return (0);
361 }
362
363 /*
364 * Squashes special XML and GDB characters down to _. Sorry.
365 */
366 static void
367 qXfer_escape_xmlattr_str(char *dst, size_t dstlen, const char *src)
368 {
369 static const char *forbidden = "#$}*";
370
371 size_t i;
372 char c;
373
374 for (i = 0; i < dstlen - 1 && *src != 0; src++, i++) {
375 c = *src;
376 /* XML attr filter */
377 if (c < 32)
378 c = '_';
379 /* We assume attributes will be "" quoted. */
380 if (c == '<' || c == '&' || c == '"')
381 c = '_';
382
383 /* GDB escape. */
384 if (strchr(forbidden, c) != NULL) {
385 /*
386 * It would be nice to escape these properly, but to do
387 * it correctly we need to escape them in the transmit
388 * layer, potentially doubling our buffer requirements.
389 * For now, avoid breaking the protocol by squashing
390 * them to underscore.
391 */
392 #if 0
393 *dst++ = '}';
394 c ^= 0x20;
395 #endif
396 c = '_';
397 }
398 *dst++ = c;
399 }
400 if (*src != 0)
401 printf("XXX%s: overflow; API misuse\n", __func__);
402
403 *dst = 0;
404 }
405
406 /*
407 * Dynamically generate qXfer:threads document, one packet at a time.
408 *
409 * The format is loosely described[0], although it does not seem that the
410 * <?xml?> mentioned on that page is required.
411 *
412 * [0]: https://sourceware.org/gdb/current/onlinedocs/gdb/Thread-List-Format.html
413 */
414 static void
415 do_qXfer_threads_read(void)
416 {
417 /* Kludgy context */
418 static struct {
419 struct qXfer_context qXfer;
420 /* Kludgy state machine */
421 struct thread *iter;
422 enum {
423 XML_START_THREAD, /* '<thread' */
424 XML_THREAD_ID, /* ' id="xxx"' */
425 XML_THREAD_CORE, /* ' core="yyy"' */
426 XML_THREAD_NAME, /* ' name="zzz"' */
427 XML_THREAD_EXTRA, /* '> ...' */
428 XML_END_THREAD, /* '</thread>' */
429 XML_SENT_END_THREADS, /* '</threads>' */
430 } next_step;
431 } ctx;
432 static char td_name_escape[MAXCOMLEN * 2 + 1];
433
434 const char *name_src;
435 uintmax_t offset, len;
436 int error;
437
438 /* Annex part must be empty. */
439 if (gdb_rx_char() != ':')
440 goto misformed_request;
441
442 if (gdb_rx_varhex(&offset) != 0 ||
443 gdb_rx_char() != ',' ||
444 gdb_rx_varhex(&len) != 0)
445 goto misformed_request;
446
447 /*
448 * Validate resume xfers.
449 */
450 if (offset != 0) {
451 if (offset != ctx.qXfer.last_offset) {
452 printf("%s: Resumed offset %ju != expected %zu\n",
453 __func__, offset, ctx.qXfer.last_offset);
454 error = ESPIPE;
455 goto request_error;
456 }
457 ctx.qXfer.flushed = false;
458 }
459
460 if (offset == 0) {
461 ctx.iter = kdb_thr_first();
462 ctx.next_step = XML_START_THREAD;
463 error = init_qXfer_ctx(&ctx.qXfer, len);
464 if (error != 0)
465 goto request_error;
466
467 sbuf_cat(&ctx.qXfer.sb, "<threads>");
468 }
469
470 while (!ctx.qXfer.flushed && ctx.iter != NULL) {
471 switch (ctx.next_step) {
472 case XML_START_THREAD:
473 ctx.next_step = XML_THREAD_ID;
474 sbuf_cat(&ctx.qXfer.sb, "<thread");
475 continue;
476
477 case XML_THREAD_ID:
478 ctx.next_step = XML_THREAD_CORE;
479 sbuf_printf(&ctx.qXfer.sb, " id=\"%jx\"",
480 (uintmax_t)ctx.iter->td_tid);
481 continue;
482
483 case XML_THREAD_CORE:
484 ctx.next_step = XML_THREAD_NAME;
485 if (ctx.iter->td_oncpu != NOCPU) {
486 sbuf_printf(&ctx.qXfer.sb, " core=\"%d\"",
487 ctx.iter->td_oncpu);
488 }
489 continue;
490
491 case XML_THREAD_NAME:
492 ctx.next_step = XML_THREAD_EXTRA;
493
494 if (ctx.iter->td_name[0] != 0)
495 name_src = ctx.iter->td_name;
496 else if (ctx.iter->td_proc != NULL &&
497 ctx.iter->td_proc->p_comm[0] != 0)
498 name_src = ctx.iter->td_proc->p_comm;
499 else
500 continue;
501
502 qXfer_escape_xmlattr_str(td_name_escape,
503 sizeof(td_name_escape), name_src);
504 sbuf_printf(&ctx.qXfer.sb, " name=\"%s\"",
505 td_name_escape);
506 continue;
507
508 case XML_THREAD_EXTRA:
509 ctx.next_step = XML_END_THREAD;
510
511 sbuf_putc(&ctx.qXfer.sb, '>');
512
513 if (ctx.iter->td_state == TDS_RUNNING)
514 sbuf_cat(&ctx.qXfer.sb, "Running");
515 else if (ctx.iter->td_state == TDS_RUNQ)
516 sbuf_cat(&ctx.qXfer.sb, "RunQ");
517 else if (ctx.iter->td_state == TDS_CAN_RUN)
518 sbuf_cat(&ctx.qXfer.sb, "CanRun");
519 else if (TD_ON_LOCK(ctx.iter))
520 sbuf_cat(&ctx.qXfer.sb, "Blocked");
521 else if (TD_IS_SLEEPING(ctx.iter))
522 sbuf_cat(&ctx.qXfer.sb, "Sleeping");
523 else if (TD_IS_SWAPPED(ctx.iter))
524 sbuf_cat(&ctx.qXfer.sb, "Swapped");
525 else if (TD_AWAITING_INTR(ctx.iter))
526 sbuf_cat(&ctx.qXfer.sb, "IthreadWait");
527 else if (TD_IS_SUSPENDED(ctx.iter))
528 sbuf_cat(&ctx.qXfer.sb, "Suspended");
529 else
530 sbuf_cat(&ctx.qXfer.sb, "???");
531 continue;
532
533 case XML_END_THREAD:
534 ctx.next_step = XML_START_THREAD;
535 sbuf_cat(&ctx.qXfer.sb, "</thread>");
536 ctx.iter = kdb_thr_next(ctx.iter);
537 continue;
538
539 /*
540 * This one isn't part of the looping state machine,
541 * but GCC complains if you leave an enum value out of the
542 * select.
543 */
544 case XML_SENT_END_THREADS:
545 /* NOTREACHED */
546 break;
547 }
548 }
549 if (ctx.qXfer.flushed)
550 return;
551
552 if (ctx.next_step != XML_SENT_END_THREADS) {
553 ctx.next_step = XML_SENT_END_THREADS;
554 sbuf_cat(&ctx.qXfer.sb, "</threads>");
555 }
556 if (ctx.qXfer.flushed)
557 return;
558
559 ctx.qXfer.lastmessage = true;
560 sbuf_finish(&ctx.qXfer.sb);
561 sbuf_delete(&ctx.qXfer.sb);
562 ctx.qXfer.last_offset = 0;
563 return;
564
565 misformed_request:
566 /*
567 * GDB "General-Query-Packets.html" qXfer-read anchor specifically
568 * documents an E00 code for malformed requests or invalid annex.
569 * Non-zero codes indicate invalid offset or "error reading the data."
570 */
571 error = 0;
572 request_error:
573 gdb_tx_err(error);
574 return;
575 }
576
577 /*
578 * A set of standardized transfers from "special data areas."
579 *
580 * We've already matched on "qXfer:" and advanced the rx packet buffer past
581 * that bit. Parse out the rest of the packet and generate an appropriate
582 * response.
583 */
584 static void
585 do_qXfer(void)
586 {
587 if (!gdb_rx_equal("threads:"))
588 goto unrecognized;
589
590 if (!gdb_rx_equal("read:"))
591 goto unrecognized;
592
593 do_qXfer_threads_read();
594 return;
595
596 unrecognized:
597 gdb_tx_empty();
598 return;
599 }
600
601 static void
602 gdb_handle_detach(void)
603 {
604 kdb_cpu_clear_singlestep();
605 gdb_listening = 0;
606
607 if (gdb_cur->gdb_dbfeatures & GDB_DBGP_FEAT_WANTTERM)
608 gdb_cur->gdb_term();
609
610 #ifdef DDB
611 if (!gdb_return_to_ddb)
612 return;
613
614 gdb_return_to_ddb = false;
615
616 if (kdb_dbbe_select("ddb") != 0)
617 printf("The ddb backend could not be selected.\n");
618 #endif
619 }
620
621 static int
622 gdb_trap(int type, int code)
623 {
624 jmp_buf jb;
625 struct thread *thr_iter;
626 void *prev_jb;
627 uint32_t host_features;
628
629 prev_jb = kdb_jmpbuf(jb);
630 if (setjmp(jb) != 0) {
631 printf("%s bailing, hopefully back to ddb!\n", __func__);
632 gdb_listening = 0;
633 (void)kdb_jmpbuf(prev_jb);
634 return (1);
635 }
636
637 gdb_listening = 0;
638 gdb_ackmode = true;
639
640 /*
641 * Send a T packet. We currently do not support watchpoints (the
642 * awatch, rwatch or watch elements).
643 */
644 gdb_tx_begin('T');
645 gdb_tx_hex(gdb_cpu_signal(type, code), 2);
646 gdb_tx_varhex(GDB_REG_PC);
647 gdb_tx_char(':');
648 gdb_tx_reg(GDB_REG_PC);
649 gdb_tx_char(';');
650 gdb_tx_str("thread:");
651 gdb_tx_varhex((long)kdb_thread->td_tid);
652 gdb_tx_char(';');
653 gdb_tx_end(); /* XXX check error condition. */
654
655 thr_iter = NULL;
656 while (gdb_rx_begin() == 0) {
657 /* printf("GDB: got '%s'\n", gdb_rxp); */
658 switch (gdb_rx_char()) {
659 case '?': /* Last signal. */
660 gdb_tx_begin('T');
661 gdb_tx_hex(gdb_cpu_signal(type, code), 2);
662 gdb_tx_str("thread:");
663 gdb_tx_varhex((long)kdb_thread->td_tid);
664 gdb_tx_char(';');
665 gdb_tx_end();
666 break;
667 case 'c': { /* Continue. */
668 uintmax_t addr;
669 register_t pc;
670 if (!gdb_rx_varhex(&addr)) {
671 pc = addr;
672 gdb_cpu_setreg(GDB_REG_PC, &pc);
673 }
674 kdb_cpu_clear_singlestep();
675 gdb_listening = 1;
676 return (1);
677 }
678 case 'C': { /* Continue with signal. */
679 uintmax_t addr, sig;
680 register_t pc;
681 if (!gdb_rx_varhex(&sig) && gdb_rx_char() == ';' &&
682 !gdb_rx_varhex(&addr)) {
683 pc = addr;
684 gdb_cpu_setreg(GDB_REG_PC, &pc);
685 }
686 kdb_cpu_clear_singlestep();
687 gdb_listening = 1;
688 return (1);
689 }
690 case 'D': { /* Detach */
691 gdb_tx_ok();
692 gdb_handle_detach();
693 return (1);
694 }
695 case 'g': { /* Read registers. */
696 size_t r;
697 gdb_tx_begin(0);
698 for (r = 0; r < GDB_NREGS; r++)
699 gdb_tx_reg(r);
700 gdb_tx_end();
701 break;
702 }
703 case 'G': { /* Write registers. */
704 char *val;
705 bool success;
706 size_t r;
707 for (success = true, r = 0; r < GDB_NREGS; r++) {
708 val = gdb_rxp;
709 if (!gdb_rx_mem(val, gdb_cpu_regsz(r))) {
710 gdb_tx_err(EINVAL);
711 success = false;
712 break;
713 }
714 gdb_cpu_setreg(r, val);
715 }
716 if (success)
717 gdb_tx_ok();
718 break;
719 }
720 case 'H': { /* Set thread. */
721 intmax_t tid;
722 struct thread *thr;
723
724 /* Ignore 'g' (general) or 'c' (continue) flag. */
725 (void) gdb_rx_char();
726
727 if (gdb_rx_varhex(&tid)) {
728 gdb_tx_err(EINVAL);
729 break;
730 }
731 if (tid > 0) {
732 thr = kdb_thr_lookup(tid);
733 if (thr == NULL) {
734 gdb_tx_err(ENOENT);
735 break;
736 }
737 kdb_thr_select(thr);
738 }
739 gdb_tx_ok();
740 break;
741 }
742 case 'k': /* Kill request. */
743 gdb_handle_detach();
744 return (1);
745 case 'm': { /* Read memory. */
746 uintmax_t addr, size;
747 if (gdb_rx_varhex(&addr) || gdb_rx_char() != ',' ||
748 gdb_rx_varhex(&size)) {
749 gdb_tx_err(EINVAL);
750 break;
751 }
752 gdb_tx_begin(0);
753 if (gdb_tx_mem((char *)(uintptr_t)addr, size))
754 gdb_tx_end();
755 else
756 gdb_tx_err(EIO);
757 break;
758 }
759 case 'M': { /* Write memory. */
760 uintmax_t addr, size;
761 if (gdb_rx_varhex(&addr) || gdb_rx_char() != ',' ||
762 gdb_rx_varhex(&size) || gdb_rx_char() != ':') {
763 gdb_tx_err(EINVAL);
764 break;
765 }
766 if (gdb_rx_mem((char *)(uintptr_t)addr, size) == 0)
767 gdb_tx_err(EIO);
768 else
769 gdb_tx_ok();
770 break;
771 }
772 case 'p': { /* Read register. */
773 uintmax_t reg;
774 if (gdb_rx_varhex(®)) {
775 gdb_tx_err(EINVAL);
776 break;
777 }
778 gdb_tx_begin(0);
779 gdb_tx_reg(reg);
780 gdb_tx_end();
781 break;
782 }
783 case 'P': { /* Write register. */
784 char *val;
785 uintmax_t reg;
786 val = gdb_rxp;
787 if (gdb_rx_varhex(®) || gdb_rx_char() != '=' ||
788 !gdb_rx_mem(val, gdb_cpu_regsz(reg))) {
789 gdb_tx_err(EINVAL);
790 break;
791 }
792 gdb_cpu_setreg(reg, val);
793 gdb_tx_ok();
794 break;
795 }
796 case 'q': /* General query. */
797 if (gdb_rx_equal("C")) {
798 gdb_tx_begin('Q');
799 gdb_tx_char('C');
800 gdb_tx_varhex((long)kdb_thread->td_tid);
801 gdb_tx_end();
802 } else if (gdb_rx_equal("Supported")) {
803 gdb_do_qsupported(&host_features);
804 } else if (gdb_rx_equal("fThreadInfo")) {
805 thr_iter = kdb_thr_first();
806 gdb_do_threadinfo(&thr_iter);
807 } else if (gdb_rx_equal("sThreadInfo")) {
808 gdb_do_threadinfo(&thr_iter);
809 } else if (gdb_rx_equal("Xfer:")) {
810 do_qXfer();
811 } else if (gdb_rx_equal("Search:memory:")) {
812 gdb_do_mem_search();
813 #ifdef __powerpc__
814 } else if (gdb_rx_equal("Offsets")) {
815 gdb_cpu_do_offsets();
816 #endif
817 } else if (!gdb_cpu_query())
818 gdb_tx_empty();
819 break;
820 case 'Q':
821 if (gdb_rx_equal("StartNoAckMode")) {
822 if ((gdb_cur->gdb_dbfeatures &
823 GDB_DBGP_FEAT_RELIABLE) == 0) {
824 /*
825 * Shouldn't happen if we didn't
826 * advertise support. Reject.
827 */
828 gdb_tx_empty();
829 break;
830 }
831 gdb_ackmode = false;
832 gdb_tx_ok();
833 } else
834 gdb_tx_empty();
835 break;
836 case 's': { /* Step. */
837 uintmax_t addr;
838 register_t pc;
839 if (!gdb_rx_varhex(&addr)) {
840 pc = addr;
841 gdb_cpu_setreg(GDB_REG_PC, &pc);
842 }
843 kdb_cpu_set_singlestep();
844 gdb_listening = 1;
845 return (1);
846 }
847 case 'S': { /* Step with signal. */
848 uintmax_t addr, sig;
849 register_t pc;
850 if (!gdb_rx_varhex(&sig) && gdb_rx_char() == ';' &&
851 !gdb_rx_varhex(&addr)) {
852 pc = addr;
853 gdb_cpu_setreg(GDB_REG_PC, &pc);
854 }
855 kdb_cpu_set_singlestep();
856 gdb_listening = 1;
857 return (1);
858 }
859 case 'T': { /* Thread alive. */
860 intmax_t tid;
861 if (gdb_rx_varhex(&tid)) {
862 gdb_tx_err(EINVAL);
863 break;
864 }
865 if (kdb_thr_lookup(tid) != NULL)
866 gdb_tx_ok();
867 else
868 gdb_tx_err(ENOENT);
869 break;
870 }
871 case EOF:
872 /* Empty command. Treat as unknown command. */
873 /* FALLTHROUGH */
874 default:
875 /* Unknown command. Send empty response. */
876 gdb_tx_empty();
877 break;
878 }
879 }
880 (void)kdb_jmpbuf(prev_jb);
881 return (0);
882 }
Cache object: 3a683c1a79dfc08add346308619c560e
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