VirtualBox

source: vbox/trunk/src/VBox/VMM/DBGF.cpp@ 9176

Last change on this file since 9176 was 8823, checked in by vboxsync, 17 years ago

Don't loop forever in DBGFR3Term if the debugger and EMT race each other.

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1/* $Id: DBGF.cpp 8823 2008-05-14 21:51:07Z vboxsync $ */
2/** @file
3 * VMM DBGF - Debugger Facility.
4 */
5
6/*
7 * Copyright (C) 2006-2007 Sun Microsystems, Inc.
8 *
9 * This file is part of VirtualBox Open Source Edition (OSE), as
10 * available from http://www.virtualbox.org. This file is free software;
11 * you can redistribute it and/or modify it under the terms of the GNU
12 * General Public License (GPL) as published by the Free Software
13 * Foundation, in version 2 as it comes in the "COPYING" file of the
14 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16 *
17 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
18 * Clara, CA 95054 USA or visit http://www.sun.com if you need
19 * additional information or have any questions.
20 */
21
22
23/** @page pg_dbgf DBGC - The Debugger Facility
24 *
25 * The purpose of the DBGC is to provide an interface for debuggers to manipulate
26 * the VMM without having to mess up the source code for each of them. The DBGF
27 * is always built in and will always work when a debugger attaches to the VM.
28 * The DBGF provides the basic debugger features, such as halting execution,
29 * handling breakpoints and single step execution.
30 *
31 * The interface is working in a manner similar to the win32, linux and os2
32 * debugger interfaces. It interface has an asynchronous nature. This comes from
33 * the fact that the VMM and the Debugger are running in different threads.
34 * They are refered to as the "emulation thread" and the "debugger thread",
35 * or as the "ping thread" and the "pong thread, respectivly. (The last set
36 * of names comes from the use of the Ping-Pong synchronization construct from
37 * the RTSem API.)
38 *
39 *
40 *
41 * @section sec_dbgf_scenario Debugger Scenario
42 *
43 * The debugger starts by attaching to the VM. For pratical reasons we limit the
44 * number of concurrently attached debuggers to 1 per VM. The action of attaching
45 * to the VM causes the VM to check and generate debug events.
46 *
47 * The debugger then will wait/poll for debug events and issue commands.
48 *
49 * The waiting and polling is done by the DBGFEventWait() function. It will wait
50 * for the emulation thread to send a ping, thus indicating that there is an
51 * event waiting to be processed.
52 *
53 * An event can be a respons to an command issued previously, the hitting of a
54 * breakpoint, or running into a bad/fatal VMM condition. The debugger now have
55 * the ping and must respond to the event at hand - the VMM is waiting. This
56 * usually means that the user of the debugger must do something, but it doesn't
57 * have to. The debugger is free to call any DBGF function (nearly at least)
58 * while processing the event.
59 *
60 * Typically the user will issue a request for the execution to be resumed, so
61 * the debugger calls DBGFResume() and goes back to waiting/polling for events.
62 *
63 * When the user eventually terminates the debugging session or selects another
64 * VM, the debugger detaches from the VM. This means that breakpoints are disabled
65 * and that the emulation thread no longer polls for debugger commands.
66 *
67 */
68
69
70
71/*******************************************************************************
72* Header Files *
73*******************************************************************************/
74#define LOG_GROUP LOG_GROUP_DBGF
75#include <VBox/dbgf.h>
76#include <VBox/selm.h>
77#include <VBox/rem.h>
78#include <VBox/em.h>
79#include "DBGFInternal.h"
80#include <VBox/vm.h>
81#include <VBox/err.h>
82
83#include <VBox/log.h>
84#include <iprt/semaphore.h>
85#include <iprt/thread.h>
86#include <iprt/asm.h>
87#include <iprt/time.h>
88#include <iprt/assert.h>
89#include <iprt/stream.h>
90
91
92/*******************************************************************************
93* Internal Functions *
94*******************************************************************************/
95static int dbgfr3VMMWait(PVM pVM);
96static int dbgfr3VMMCmd(PVM pVM, DBGFCMD enmCmd, PDBGFCMDDATA pCmdData, bool *pfResumeExecution);
97
98
99/**
100 * Sets the VMM Debug Command variable.
101 *
102 * @returns Previous command.
103 * @param pVM VM Handle.
104 * @param enmCmd The command.
105 */
106DECLINLINE(DBGFCMD) dbgfr3SetCmd(PVM pVM, DBGFCMD enmCmd)
107{
108 DBGFCMD rc;
109 if (enmCmd == DBGFCMD_NO_COMMAND)
110 {
111 Log2(("DBGF: Setting command to %d (DBGFCMD_NO_COMMAND)\n", enmCmd));
112 rc = (DBGFCMD)ASMAtomicXchgU32((uint32_t volatile *)(void *)&pVM->dbgf.s.enmVMMCmd, enmCmd);
113 VM_FF_CLEAR(pVM, VM_FF_DBGF);
114 }
115 else
116 {
117 Log2(("DBGF: Setting command to %d\n", enmCmd));
118 AssertMsg(pVM->dbgf.s.enmVMMCmd == DBGFCMD_NO_COMMAND, ("enmCmd=%d enmVMMCmd=%d\n", enmCmd, pVM->dbgf.s.enmVMMCmd));
119 rc = (DBGFCMD)ASMAtomicXchgU32((uint32_t volatile *)(void *)&pVM->dbgf.s.enmVMMCmd, enmCmd);
120 VM_FF_SET(pVM, VM_FF_DBGF);
121 VMR3NotifyFF(pVM, false /* didn't notify REM */);
122 }
123 return rc;
124}
125
126
127/**
128 * Initializes the DBGF.
129 *
130 * @returns VBox status code.
131 * @param pVM VM handle.
132 */
133DBGFR3DECL(int) DBGFR3Init(PVM pVM)
134{
135 int rc = dbgfR3InfoInit(pVM);
136 if (VBOX_SUCCESS(rc))
137 rc = dbgfR3SymInit(pVM);
138 if (VBOX_SUCCESS(rc))
139 rc = dbgfR3BpInit(pVM);
140 return rc;
141}
142
143
144/**
145 * Termiantes and cleans up resources allocated by the DBGF.
146 *
147 * @returns VBox status code.
148 * @param pVM VM Handle.
149 */
150DBGFR3DECL(int) DBGFR3Term(PVM pVM)
151{
152 int rc;
153
154 /*
155 * Send a termination event to any attached debuggers.
156 */
157 /* wait for any pending events or whatever */
158 if ( pVM->dbgf.s.fAttached
159 && pVM->dbgf.s.PingPong.enmSpeaker == RTPINGPONGSPEAKER_PONG)
160 {
161 RTThreadSleep(32); /* Don't want that assertion if we can help it. */
162 while ( pVM->dbgf.s.fAttached
163 && pVM->dbgf.s.PingPong.enmSpeaker == RTPINGPONGSPEAKER_PONG)
164 if (RTSemPingWait(&pVM->dbgf.s.PingPong, 5000) != VERR_TIMEOUT)
165 break;
166 }
167
168 /* now, send the event */
169 if ( pVM->dbgf.s.fAttached
170 && pVM->dbgf.s.PingPong.enmSpeaker != RTPINGPONGSPEAKER_PONG)
171 {
172 pVM->dbgf.s.DbgEvent.enmType = DBGFEVENT_TERMINATING;
173 pVM->dbgf.s.DbgEvent.enmCtx = DBGFEVENTCTX_OTHER;
174 rc = RTSemPing(&pVM->dbgf.s.PingPong);
175 if (VBOX_SUCCESS(rc))
176 {
177 /*
178 * Waits for the debugger to detach.
179 */
180 while (pVM->dbgf.s.fAttached)
181 {
182 /*
183 * Wait.
184 */
185 rc = RTSemPingWait(&pVM->dbgf.s.PingPong, 1000);
186
187 /*
188 * Process the command.
189 */
190 DBGFCMDDATA CmdData = pVM->dbgf.s.VMMCmdData;
191 DBGFCMD enmCmd = dbgfr3SetCmd(pVM, DBGFCMD_NO_COMMAND);
192 if (enmCmd != DBGFCMD_NO_COMMAND)
193 {
194 bool fResumeExecution = false;
195 rc = dbgfr3VMMCmd(pVM, enmCmd, &CmdData, &fResumeExecution);
196 if (enmCmd == DBGFCMD_DETACH_DEBUGGER)
197 break;
198 }
199 else if (VBOX_FAILURE(rc))
200 break;
201 }
202 }
203 }
204
205 /*
206 * Terminate the other bits.
207 */
208 dbgfR3OSTerm(pVM);
209 dbgfR3InfoTerm(pVM);
210 return VINF_SUCCESS;
211}
212
213
214/**
215 * Applies relocations to data and code managed by this
216 * component. This function will be called at init and
217 * whenever the VMM need to relocate it self inside the GC.
218 *
219 * @param pVM VM handle.
220 * @param offDelta Relocation delta relative to old location.
221 */
222DBGFR3DECL(void) DBGFR3Relocate(PVM pVM, RTGCINTPTR offDelta)
223{
224}
225
226
227/**
228 * Waits a little while for a debuggger to attach.
229 *
230 * @returns True is a debugger have attached.
231 * @param pVM VM handle.
232 * @param enmEvent Event.
233 */
234bool dbgfR3WaitForAttach(PVM pVM, DBGFEVENTTYPE enmEvent)
235{
236 /*
237 * First a message.
238 */
239#ifndef RT_OS_L4
240
241 RTStrmPrintf(g_pStdErr, "DBGF: No debugger attached, waiting 15 seconds for one to attach (event=%d)\n", enmEvent);
242 RTStrmFlush(g_pStdErr);
243# ifdef DEBUG_sandervl
244 int cWait = 10;
245# else
246 int cWait = 150;
247# endif
248 while (cWait > 0)
249 {
250 RTThreadSleep(100);
251 if (pVM->dbgf.s.fAttached)
252 {
253 RTStrmPrintf(g_pStdErr, "Attached!\n");
254 RTStrmFlush(g_pStdErr);
255 return true;
256 }
257
258 /* next */
259 if (!(cWait % 10))
260 {
261 RTStrmPrintf(g_pStdErr, "%d.", cWait / 10);
262 RTStrmFlush(g_pStdErr);
263 }
264 cWait--;
265 }
266#endif
267
268 RTStrmPrintf(g_pStdErr, "Stopping the VM!\n");
269 RTStrmFlush(g_pStdErr);
270 return false;
271}
272
273
274/**
275 * Forced action callback.
276 * The VMM will call this from it's main loop when VM_FF_DBGF is set.
277 *
278 * The function checks and executes pending commands from the debugger.
279 *
280 * @returns VINF_SUCCESS normally.
281 * @returns VERR_DBGF_RAISE_FATAL_ERROR to pretend a fatal error happend.
282 * @param pVM VM Handle.
283 */
284DBGFR3DECL(int) DBGFR3VMMForcedAction(PVM pVM)
285{
286 /*
287 * Clear the FF DBGF request flag.
288 */
289 Assert(pVM->fForcedActions & VM_FF_DBGF);
290 VM_FF_CLEAR(pVM, VM_FF_DBGF);
291
292 /*
293 * Commands?
294 */
295 int rc = VINF_SUCCESS;
296 if (pVM->dbgf.s.enmVMMCmd != DBGFCMD_NO_COMMAND)
297 {
298 /** @todo stupid GDT/LDT sync hack. go away! */
299 SELMR3UpdateFromCPUM(pVM);
300
301 /*
302 * Process the command.
303 */
304 bool fResumeExecution;
305 DBGFCMDDATA CmdData = pVM->dbgf.s.VMMCmdData;
306 DBGFCMD enmCmd = dbgfr3SetCmd(pVM, DBGFCMD_NO_COMMAND);
307 rc = dbgfr3VMMCmd(pVM, enmCmd, &CmdData, &fResumeExecution);
308 if (!fResumeExecution)
309 rc = dbgfr3VMMWait(pVM);
310 }
311 return rc;
312}
313
314
315/**
316 * Flag whether the event implies that we're stopped in the hypervisor code
317 * and have to block certain operations.
318 *
319 * @param pVM The VM handle.
320 * @param enmEvent The event.
321 */
322static void dbgfR3EventSetStoppedInHyperFlag(PVM pVM, DBGFEVENTTYPE enmEvent)
323{
324 switch (enmEvent)
325 {
326 case DBGFEVENT_STEPPED_HYPER:
327 case DBGFEVENT_ASSERTION_HYPER:
328 case DBGFEVENT_BREAKPOINT_HYPER:
329 pVM->dbgf.s.fStoppedInHyper = true;
330 break;
331 default:
332 pVM->dbgf.s.fStoppedInHyper = false;
333 break;
334 }
335}
336
337
338/**
339 * Try determin the event context.
340 *
341 * @returns debug event context.
342 * @param pVM The VM handle.
343 */
344static DBGFEVENTCTX dbgfR3FigureEventCtx(PVM pVM)
345{
346 switch (EMGetState(pVM))
347 {
348 case EMSTATE_RAW:
349 case EMSTATE_DEBUG_GUEST_RAW:
350 return DBGFEVENTCTX_RAW;
351
352 case EMSTATE_REM:
353 case EMSTATE_DEBUG_GUEST_REM:
354 return DBGFEVENTCTX_REM;
355
356 case EMSTATE_DEBUG_HYPER:
357 case EMSTATE_GURU_MEDITATION:
358 return DBGFEVENTCTX_HYPER;
359
360 default:
361 return DBGFEVENTCTX_OTHER;
362 }
363}
364
365/**
366 * The common event prologue code.
367 * It will set the 'stopped-in-hyper' flag, make sure someone's attach,
368 * and perhaps process any high priority pending actions (none yet).
369 *
370 * @returns VBox status.
371 * @param pVM The VM handle.
372 * @param enmEvent The event to be sent.
373 */
374static int dbgfR3EventPrologue(PVM pVM, DBGFEVENTTYPE enmEvent)
375{
376 /*
377 * Check if a debugger is attached.
378 */
379 if ( !pVM->dbgf.s.fAttached
380 && !dbgfR3WaitForAttach(pVM, enmEvent))
381 {
382 Log(("DBGFR3VMMEventSrc: enmEvent=%d - debugger not attached\n", enmEvent));
383 return VERR_DBGF_NOT_ATTACHED;
384 }
385
386 /*
387 * Sync back the state from the REM.
388 */
389 dbgfR3EventSetStoppedInHyperFlag(pVM, enmEvent);
390 if (!pVM->dbgf.s.fStoppedInHyper)
391 REMR3StateUpdate(pVM);
392
393 /*
394 * Look thru pending commands and finish those which make sense now.
395 */
396 /** @todo Process/purge pending commands. */
397 //int rc = DBGFR3VMMForcedAction(pVM);
398 return VINF_SUCCESS;
399}
400
401
402/**
403 * Sends the event in the event buffer.
404 *
405 * @returns VBox status code.
406 * @param pVM The VM handle.
407 */
408static int dbgfR3SendEvent(PVM pVM)
409{
410 int rc = RTSemPing(&pVM->dbgf.s.PingPong);
411 if (VBOX_SUCCESS(rc))
412 rc = dbgfr3VMMWait(pVM);
413
414 pVM->dbgf.s.fStoppedInHyper = false;
415 /** @todo sync VMM -> REM after exitting the debugger. everything may change while in the debugger! */
416 return rc;
417}
418
419
420/**
421 * Send a generic debugger event which takes no data.
422 *
423 * @returns VBox status.
424 * @param pVM The VM handle.
425 * @param enmEvent The event to send.
426 */
427DBGFR3DECL(int) DBGFR3Event(PVM pVM, DBGFEVENTTYPE enmEvent)
428{
429 int rc = dbgfR3EventPrologue(pVM, enmEvent);
430 if (VBOX_FAILURE(rc))
431 return rc;
432
433 /*
434 * Send the event and process the reply communication.
435 */
436 pVM->dbgf.s.DbgEvent.enmType = enmEvent;
437 pVM->dbgf.s.DbgEvent.enmCtx = dbgfR3FigureEventCtx(pVM);
438 return dbgfR3SendEvent(pVM);
439}
440
441
442/**
443 * Send a debugger event which takes the full source file location.
444 *
445 * @returns VBox status.
446 * @param pVM The VM handle.
447 * @param enmEvent The event to send.
448 * @param pszFile Source file.
449 * @param uLine Line number in source file.
450 * @param pszFunction Function name.
451 * @param pszFormat Message which accompanies the event.
452 * @param ... Message arguments.
453 */
454DBGFR3DECL(int) DBGFR3EventSrc(PVM pVM, DBGFEVENTTYPE enmEvent, const char *pszFile, unsigned uLine, const char *pszFunction, const char *pszFormat, ...)
455{
456 va_list args;
457 va_start(args, pszFormat);
458 int rc = DBGFR3EventSrcV(pVM, enmEvent, pszFile, uLine, pszFunction, pszFormat, args);
459 va_end(args);
460 return rc;
461}
462
463
464/**
465 * Send a debugger event which takes the full source file location.
466 *
467 * @returns VBox status.
468 * @param pVM The VM handle.
469 * @param enmEvent The event to send.
470 * @param pszFile Source file.
471 * @param uLine Line number in source file.
472 * @param pszFunction Function name.
473 * @param pszFormat Message which accompanies the event.
474 * @param args Message arguments.
475 */
476DBGFR3DECL(int) DBGFR3EventSrcV(PVM pVM, DBGFEVENTTYPE enmEvent, const char *pszFile, unsigned uLine, const char *pszFunction, const char *pszFormat, va_list args)
477{
478 int rc = dbgfR3EventPrologue(pVM, enmEvent);
479 if (VBOX_FAILURE(rc))
480 return rc;
481
482 /*
483 * Format the message.
484 */
485 char *pszMessage = NULL;
486 char szMessage[8192];
487 if (pszFormat && *pszFormat)
488 {
489 pszMessage = &szMessage[0];
490 RTStrPrintfV(szMessage, sizeof(szMessage), pszFormat, args);
491 }
492
493 /*
494 * Send the event and process the reply communication.
495 */
496 pVM->dbgf.s.DbgEvent.enmType = enmEvent;
497 pVM->dbgf.s.DbgEvent.enmCtx = dbgfR3FigureEventCtx(pVM);
498 pVM->dbgf.s.DbgEvent.u.Src.pszFile = pszFile;
499 pVM->dbgf.s.DbgEvent.u.Src.uLine = uLine;
500 pVM->dbgf.s.DbgEvent.u.Src.pszFunction = pszFunction;
501 pVM->dbgf.s.DbgEvent.u.Src.pszMessage = pszMessage;
502 return dbgfR3SendEvent(pVM);
503}
504
505
506/**
507 * Send a debugger event which takes the two assertion messages.
508 *
509 * @returns VBox status.
510 * @param pVM The VM handle.
511 * @param enmEvent The event to send.
512 * @param pszMsg1 First assertion message.
513 * @param pszMsg2 Second assertion message.
514 */
515DBGFR3DECL(int) DBGFR3EventAssertion(PVM pVM, DBGFEVENTTYPE enmEvent, const char *pszMsg1, const char *pszMsg2)
516{
517 int rc = dbgfR3EventPrologue(pVM, enmEvent);
518 if (VBOX_FAILURE(rc))
519 return rc;
520
521 /*
522 * Send the event and process the reply communication.
523 */
524 pVM->dbgf.s.DbgEvent.enmType = enmEvent;
525 pVM->dbgf.s.DbgEvent.enmCtx = dbgfR3FigureEventCtx(pVM);
526 pVM->dbgf.s.DbgEvent.u.Assert.pszMsg1 = pszMsg1;
527 pVM->dbgf.s.DbgEvent.u.Assert.pszMsg2 = pszMsg2;
528 return dbgfR3SendEvent(pVM);
529}
530
531
532/**
533 * Breakpoint was hit somewhere.
534 * Figure out which breakpoint it is and notify the debugger.
535 *
536 * @returns VBox status.
537 * @param pVM The VM handle.
538 * @param enmEvent DBGFEVENT_BREAKPOINT_HYPER or DBGFEVENT_BREAKPOINT.
539 */
540DBGFR3DECL(int) DBGFR3EventBreakpoint(PVM pVM, DBGFEVENTTYPE enmEvent)
541{
542 int rc = dbgfR3EventPrologue(pVM, enmEvent);
543 if (VBOX_FAILURE(rc))
544 return rc;
545
546 /*
547 * Send the event and process the reply communication.
548 */
549 pVM->dbgf.s.DbgEvent.enmType = enmEvent;
550 RTUINT iBp = pVM->dbgf.s.DbgEvent.u.Bp.iBp = pVM->dbgf.s.iActiveBp;
551 pVM->dbgf.s.iActiveBp = ~0U;
552 if (iBp != ~0U)
553 pVM->dbgf.s.DbgEvent.enmCtx = DBGFEVENTCTX_RAW;
554 else
555 {
556 /* REM breakpoints has be been searched for. */
557#if 0 /** @todo get flat PC api! */
558 uint32_t eip = CPUMGetGuestEIP(pVM);
559#else
560 PCPUMCTX pCtx;
561 CPUMQueryGuestCtxPtr(pVM, &pCtx);
562 uint32_t eip = pCtx->eip + pCtx->csHid.u32Base;
563#endif
564 for (iBp = 0; iBp < ELEMENTS(pVM->dbgf.s.aBreakpoints); iBp++)
565 if ( pVM->dbgf.s.aBreakpoints[iBp].enmType == DBGFBPTYPE_REM
566 && pVM->dbgf.s.aBreakpoints[iBp].GCPtr == eip)
567 {
568 pVM->dbgf.s.DbgEvent.u.Bp.iBp = iBp;
569 break;
570 }
571 AssertMsg(pVM->dbgf.s.DbgEvent.u.Bp.iBp != ~0U, ("eip=%08x\n", eip));
572 pVM->dbgf.s.DbgEvent.enmCtx = DBGFEVENTCTX_REM;
573 }
574 return dbgfR3SendEvent(pVM);
575}
576
577
578/**
579 * Waits for the debugger to respond.
580 *
581 * @returns VBox status. (clearify)
582 * @param pVM VM handle.
583 */
584static int dbgfr3VMMWait(PVM pVM)
585{
586 LogFlow(("dbgfr3VMMWait:\n"));
587
588 /** @todo stupid GDT/LDT sync hack. go away! */
589 SELMR3UpdateFromCPUM(pVM);
590 int rcRet = VINF_SUCCESS;
591
592 /*
593 * Waits for the debugger to reply (i.e. issue an command).
594 */
595 for (;;)
596 {
597 /*
598 * Wait.
599 */
600 for (;;)
601 {
602 int rc = RTSemPingWait(&pVM->dbgf.s.PingPong, 250);
603 if (VBOX_SUCCESS(rc))
604 break;
605 if (rc != VERR_TIMEOUT)
606 {
607 LogFlow(("dbgfr3VMMWait: returns %Vrc\n", rc));
608 return rc;
609 }
610
611 if (VM_FF_ISSET(pVM, VM_FF_REQUEST))
612 {
613 LogFlow(("dbgfr3VMMWait: Processes requests...\n"));
614 rc = VMR3ReqProcessU(pVM->pUVM);
615 LogFlow(("dbgfr3VMMWait: VMR3ReqProcess -> %Vrc rcRet=%Vrc\n", rc, rcRet));
616 if (rc >= VINF_EM_FIRST && rc <= VINF_EM_LAST)
617 {
618 switch (rc)
619 {
620 case VINF_EM_DBG_BREAKPOINT:
621 case VINF_EM_DBG_STEPPED:
622 case VINF_EM_DBG_STEP:
623 case VINF_EM_DBG_STOP:
624 AssertMsgFailed(("rc=%Vrc\n", rc));
625 break;
626
627 /* return straight away */
628 case VINF_EM_TERMINATE:
629 case VINF_EM_OFF:
630 LogFlow(("dbgfr3VMMWait: returns %Vrc\n", rc));
631 return rc;
632
633 /* remember return code. */
634 default:
635 AssertReleaseMsgFailed(("rc=%Vrc is not in the switch!\n", rc));
636 case VINF_EM_RESET:
637 case VINF_EM_SUSPEND:
638 case VINF_EM_HALT:
639 case VINF_EM_RESUME:
640 case VINF_EM_RESCHEDULE:
641 case VINF_EM_RESCHEDULE_REM:
642 case VINF_EM_RESCHEDULE_RAW:
643 if (rc < rcRet || rcRet == VINF_SUCCESS)
644 rcRet = rc;
645 break;
646 }
647 }
648 else if (VBOX_FAILURE(rc))
649 {
650 LogFlow(("dbgfr3VMMWait: returns %Vrc\n", rc));
651 return rc;
652 }
653 }
654 }
655
656 /*
657 * Process the command.
658 */
659 bool fResumeExecution;
660 DBGFCMDDATA CmdData = pVM->dbgf.s.VMMCmdData;
661 DBGFCMD enmCmd = dbgfr3SetCmd(pVM, DBGFCMD_NO_COMMAND);
662 int rc = dbgfr3VMMCmd(pVM, enmCmd, &CmdData, &fResumeExecution);
663 if (fResumeExecution)
664 {
665 if (VBOX_FAILURE(rc))
666 rcRet = rc;
667 else if ( rc >= VINF_EM_FIRST
668 && rc <= VINF_EM_LAST
669 && (rc < rcRet || rcRet == VINF_SUCCESS))
670 rcRet = rc;
671 LogFlow(("dbgfr3VMMWait: returns %Vrc\n", rcRet));
672 return rcRet;
673 }
674 }
675}
676
677
678/**
679 * Executes command from debugger.
680 * The caller is responsible for waiting or resuming execution based on the
681 * value returned in the *pfResumeExecution indicator.
682 *
683 * @returns VBox status. (clearify!)
684 * @param pVM VM Handle.
685 * @param enmCmd The command in question.
686 * @param pCmdData Pointer to the command data.
687 * @param pfResumeExecution Where to store the resume execution / continue waiting indicator.
688 */
689static int dbgfr3VMMCmd(PVM pVM, DBGFCMD enmCmd, PDBGFCMDDATA pCmdData, bool *pfResumeExecution)
690{
691 bool fSendEvent;
692 bool fResume;
693 int rc = VINF_SUCCESS;
694
695 switch (enmCmd)
696 {
697 /*
698 * Halt is answered by an event say that we've halted.
699 */
700 case DBGFCMD_HALT:
701 {
702 pVM->dbgf.s.DbgEvent.enmType = DBGFEVENT_HALT_DONE;
703 pVM->dbgf.s.DbgEvent.enmCtx = dbgfR3FigureEventCtx(pVM);
704 fSendEvent = true;
705 fResume = false;
706 break;
707 }
708
709
710 /*
711 * Resume is not answered we'll just resume execution.
712 */
713 case DBGFCMD_GO:
714 {
715 fSendEvent = false;
716 fResume = true;
717 break;
718 }
719
720 /** @todo implement (and define) the rest of the commands. */
721
722 /*
723 * Disable breakpoints and stuff.
724 * Send an everythings cool event to the debugger thread and resume execution.
725 */
726 case DBGFCMD_DETACH_DEBUGGER:
727 {
728 pVM->dbgf.s.DbgEvent.enmType = DBGFEVENT_DETACH_DONE;
729 pVM->dbgf.s.DbgEvent.enmCtx = DBGFEVENTCTX_OTHER;
730 VM_FF_CLEAR(pVM, VM_FF_DBGF);
731 pVM->dbgf.s.fAttached = false;
732 fSendEvent = true;
733 fResume = true;
734 break;
735 }
736
737 /*
738 * Single step, with trace into.
739 */
740 case DBGFCMD_SINGLE_STEP:
741 {
742 Log2(("Single step\n"));
743 rc = VINF_EM_DBG_STEP;
744 pVM->dbgf.s.fSingleSteppingRaw = true;
745 fSendEvent = false;
746 fResume = true;
747 break;
748 }
749
750 /*
751 * Default is to send an invalid command event.
752 */
753 default:
754 {
755 pVM->dbgf.s.DbgEvent.enmType = DBGFEVENT_INVALID_COMMAND;
756 pVM->dbgf.s.DbgEvent.enmCtx = dbgfR3FigureEventCtx(pVM);
757 fSendEvent = true;
758 fResume = false;
759 break;
760 }
761 }
762
763 /*
764 * Send pending event.
765 */
766 if (fSendEvent)
767 {
768 Log2(("DBGF: Emulation thread: sending event %d\n", pVM->dbgf.s.DbgEvent.enmType));
769 int rc2 = RTSemPing(&pVM->dbgf.s.PingPong);
770 if (VBOX_FAILURE(rc2))
771 {
772 AssertRC(rc2);
773 *pfResumeExecution = true;
774 return rc2;
775 }
776 }
777
778 /*
779 * Return.
780 */
781 *pfResumeExecution = fResume;
782 return rc;
783}
784
785
786
787
788/**
789 * Attaches a debugger to the specified VM.
790 *
791 * Only one debugger at a time.
792 *
793 * @returns VBox status code.
794 * @param pVM VM Handle.
795 */
796DBGFR3DECL(int) DBGFR3Attach(PVM pVM)
797{
798 /*
799 * Check if already attached.
800 */
801 if (pVM->dbgf.s.fAttached)
802 {
803 AssertMsgFailed(("Already attached\n"));
804 return VERR_DBGF_ALREADY_ATTACHED;
805 }
806
807 /*
808 * Create the Ping-Pong structure.
809 */
810 int rc = RTSemPingPongInit(&pVM->dbgf.s.PingPong);
811 if (rc)
812 return rc;
813
814 /*
815 * Set the attached flag.
816 */
817 pVM->dbgf.s.fAttached = true;
818 return VINF_SUCCESS;
819}
820
821
822/**
823 * Detaches a debugger from the specified VM.
824 *
825 * Caller must be attached to the VM.
826 *
827 * @returns VBox status code.
828 * @param pVM VM Handle.
829 */
830DBGFR3DECL(int) DBGFR3Detach(PVM pVM)
831{
832 LogFlowFunc(("\n"));
833
834 /*
835 * Check if attached.
836 */
837 if (!pVM->dbgf.s.fAttached)
838 {
839 AssertMsgFailed(("Not attached to VM!\n"));
840 return VERR_DBGF_NOT_ATTACHED;
841 }
842
843 /*
844 * Send detach command.
845 */
846 DBGFCMD enmCmd;
847 if (pVM->dbgf.s.PingPong.enmSpeaker == RTPINGPONGSPEAKER_PONG)
848 {
849 enmCmd = dbgfr3SetCmd(pVM, DBGFCMD_DETACH_DEBUGGER);
850 int rc = RTSemPong(&pVM->dbgf.s.PingPong);
851 if (VBOX_FAILURE(rc))
852 {
853 AssertMsgFailed(("Failed to signal emulation thread. rc=%d\n", rc));
854 return rc;
855 }
856 LogFunc(("enmCmd=%d (pong -> ping)\n", enmCmd));
857 }
858 else
859 {
860 enmCmd = dbgfr3SetCmd(pVM, DBGFCMD_DETACH_DEBUGGER);
861 LogFunc(("enmCmd=%d (ping)\n", enmCmd));
862 }
863
864 /*
865 * Wait for the ok event.
866 */
867 PCDBGFEVENT pEvent;
868 int rc = DBGFR3EventWait(pVM, RT_INDEFINITE_WAIT, &pEvent);
869 if (VBOX_FAILURE(rc))
870 {
871 AssertMsgFailed(("Wait on detach command failed, rc=%d\n", rc));
872 return rc;
873 }
874
875 /*
876 * Destroy the ping-pong construct and return.
877 */
878 ASMAtomicWriteBool(&pVM->dbgf.s.fAttached, false);
879 RTThreadSleep(10);
880 rc = RTSemPingPongDestroy(&pVM->dbgf.s.PingPong);
881 AssertRC(rc);
882
883 LogFlowFunc(("returns VINF_SUCCESS\n"));
884 return VINF_SUCCESS;
885}
886
887
888
889/**
890 * Wait for a debug event.
891 *
892 * @returns VBox status. Will not return VBOX_INTERRUPTED.
893 * @param pVM VM handle.
894 * @param cMillies Number of millies to wait.
895 * @param ppEvent Where to store the event pointer.
896 */
897DBGFR3DECL(int) DBGFR3EventWait(PVM pVM, unsigned cMillies, PCDBGFEVENT *ppEvent)
898{
899 /*
900 * Check state.
901 */
902 if (!pVM->dbgf.s.fAttached)
903 {
904 AssertMsgFailed(("Not attached to VM!\n"));
905 return VERR_DBGF_NOT_ATTACHED;
906 }
907 *ppEvent = NULL;
908
909 /*
910 * Wait.
911 */
912 int rc = RTSemPongWait(&pVM->dbgf.s.PingPong, cMillies);
913 if (VBOX_SUCCESS(rc))
914 {
915 *ppEvent = &pVM->dbgf.s.DbgEvent;
916 Log2(("DBGF: Debugger thread: receiving event %d\n", (*ppEvent)->enmType));
917 return VINF_SUCCESS;
918 }
919
920 return rc;
921}
922
923
924/**
925 * Halts VM execution.
926 *
927 * After calling this the VM isn't actually halted till an DBGFEVENT_HALT_DONE
928 * arrives. Until that time it's not possible to issue any new commands.
929 *
930 * @returns VBox status.
931 * @param pVM VM handle.
932 */
933DBGFR3DECL(int) DBGFR3Halt(PVM pVM)
934{
935 /*
936 * Check state.
937 */
938 if (!pVM->dbgf.s.fAttached)
939 {
940 AssertMsgFailed(("Not attached to VM!\n"));
941 return VERR_DBGF_NOT_ATTACHED;
942 }
943 if ( pVM->dbgf.s.PingPong.enmSpeaker == RTPINGPONGSPEAKER_PONG
944 || pVM->dbgf.s.PingPong.enmSpeaker == RTPINGPONGSPEAKER_PONG_SIGNALED)
945 return VWRN_DBGF_ALREADY_HALTED;
946
947 /*
948 * Send command.
949 */
950 dbgfr3SetCmd(pVM, DBGFCMD_HALT);
951
952 return VINF_SUCCESS;
953}
954
955
956/**
957 * Checks if the VM is halted by the debugger.
958 *
959 * @returns True if halted.
960 * @returns False if not halted.
961 * @param pVM VM handle.
962 */
963DBGFR3DECL(bool) DBGFR3IsHalted(PVM pVM)
964{
965 AssertMsg(pVM->dbgf.s.fAttached, ("Not attached to VM!\n"));
966
967 RTPINGPONGSPEAKER enmSpeaker = pVM->dbgf.s.PingPong.enmSpeaker;
968 return pVM->dbgf.s.fAttached
969 && ( enmSpeaker == RTPINGPONGSPEAKER_PONG_SIGNALED
970 || enmSpeaker == RTPINGPONGSPEAKER_PONG);
971}
972
973
974/**
975 * Checks if the the debugger can wait for events or not.
976 *
977 * This function is only used by lazy, multiplexing debuggers. :-)
978 *
979 * @returns True if waitable.
980 * @returns False if not waitable.
981 * @param pVM VM handle.
982 */
983DBGFR3DECL(bool) DBGFR3CanWait(PVM pVM)
984{
985 AssertMsg(pVM->dbgf.s.fAttached, ("Not attached to VM!\n"));
986
987 RTPINGPONGSPEAKER enmSpeaker = pVM->dbgf.s.PingPong.enmSpeaker;
988 return pVM->dbgf.s.fAttached
989 && ( enmSpeaker == RTPINGPONGSPEAKER_PING
990 || enmSpeaker == RTPINGPONGSPEAKER_PING_SIGNALED
991 || enmSpeaker == RTPINGPONGSPEAKER_PONG_SIGNALED);
992}
993
994
995/**
996 * Resumes VM execution.
997 *
998 * There is no receipt event on this command.
999 *
1000 * @returns VBox status.
1001 * @param pVM VM handle.
1002 */
1003DBGFR3DECL(int) DBGFR3Resume(PVM pVM)
1004{
1005 /*
1006 * Check state.
1007 */
1008 if (!pVM->dbgf.s.fAttached)
1009 {
1010 AssertMsgFailed(("Not attached to VM!\n"));
1011 return VERR_DBGF_NOT_ATTACHED;
1012 }
1013 if (pVM->dbgf.s.PingPong.enmSpeaker != RTPINGPONGSPEAKER_PONG)
1014 {
1015 AssertMsgFailed(("Speaking out of turn!\n"));
1016 return VERR_SEM_OUT_OF_TURN;
1017 }
1018
1019 /*
1020 * Send the ping back to the emulation thread telling it to run.
1021 */
1022 dbgfr3SetCmd(pVM, DBGFCMD_GO);
1023 int rc = RTSemPong(&pVM->dbgf.s.PingPong);
1024 AssertRC(rc);
1025
1026 return rc;
1027}
1028
1029
1030/**
1031 * Step Into.
1032 *
1033 * A single step event is generated from this command.
1034 * The current implementation is not reliable, so don't rely on the event comming.
1035 *
1036 * @returns VBox status.
1037 * @param pVM VM handle.
1038 */
1039DBGFR3DECL(int) DBGFR3Step(PVM pVM)
1040{
1041 /*
1042 * Check state.
1043 */
1044 if (!pVM->dbgf.s.fAttached)
1045 {
1046 AssertMsgFailed(("Not attached to VM!\n"));
1047 return VERR_DBGF_NOT_ATTACHED;
1048 }
1049 if (pVM->dbgf.s.PingPong.enmSpeaker != RTPINGPONGSPEAKER_PONG)
1050 {
1051 AssertMsgFailed(("Speaking out of turn!\n"));
1052 return VERR_SEM_OUT_OF_TURN;
1053 }
1054
1055 /*
1056 * Send the ping back to the emulation thread telling it to run.
1057 */
1058 dbgfr3SetCmd(pVM, DBGFCMD_SINGLE_STEP);
1059 int rc = RTSemPong(&pVM->dbgf.s.PingPong);
1060 AssertRC(rc);
1061 return rc;
1062}
1063
1064
1065/**
1066 * Call this to single step rawmode or recompiled mode.
1067 *
1068 * You must pass down the return code to the EM loop! That's
1069 * where the actual single stepping take place (at least in the
1070 * current implementation).
1071 *
1072 * @returns VINF_EM_DBG_STEP
1073 * @thread EMT
1074 */
1075DBGFR3DECL(int) DBGFR3PrgStep(PVM pVM)
1076{
1077 VM_ASSERT_EMT(pVM);
1078
1079 pVM->dbgf.s.fSingleSteppingRaw = true;
1080 return VINF_EM_DBG_STEP;
1081}
1082
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