1/*
2  This file is part of drd, a thread error detector.
3
4  Copyright (C) 2006-2013 Bart Van Assche <bvanassche@acm.org>.
5
6  This program is free software; you can redistribute it and/or
7  modify it under the terms of the GNU General Public License as
8  published by the Free Software Foundation; either version 2 of the
9  License, or (at your option) any later version.
10
11  This program is distributed in the hope that it will be useful, but
12  WITHOUT ANY WARRANTY; without even the implied warranty of
13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  General Public License for more details.
15
16  You should have received a copy of the GNU General Public License
17  along with this program; if not, write to the Free Software
18  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19  02111-1307, USA.
20
21  The GNU General Public License is contained in the file COPYING.
22*/
23
24
25#include "drd_clientobj.h"        /* struct mutex_info        */
26#include "drd_error.h"
27#include "drd_malloc_wrappers.h"
28#include "drd_mutex.h"
29#include "drd_suppression.h"      /* drd_start_suppression()  */
30#include "pub_drd_bitmap.h"       /* LHS_W, ...               */
31#include "pub_tool_vki.h"
32#include "pub_tool_basics.h"
33#include "pub_tool_libcassert.h"  /* tl_assert()              */
34#include "pub_tool_libcbase.h"    /* strlen()                 */
35#include "pub_tool_libcfile.h"    /* VG_(get_startup_wd)()    */
36#include "pub_tool_libcprint.h"   /* VG_(printf)()            */
37#include "pub_tool_machine.h"
38#include "pub_tool_mallocfree.h"  /* VG_(malloc), VG_(free)   */
39#include "pub_tool_options.h"     /* VG_(clo_xml)             */
40#include "pub_tool_threadstate.h" /* VG_(get_pthread_id)()    */
41#include "pub_tool_tooliface.h"   /* VG_(needs_tool_errors)() */
42
43
44/* Local function declarations. */
45
46static const HChar* drd_get_error_name(const Error* e);
47
48
49/* Local variables. */
50
51static Bool s_show_conflicting_segments = True;
52
53
54void DRD_(set_show_conflicting_segments)(const Bool scs)
55{
56   s_show_conflicting_segments = scs;
57}
58
59void DRD_(trace_msg)(const HChar* format, ...)
60{
61   va_list vargs;
62   va_start(vargs, format);
63   if (VG_(clo_xml)) {
64      VG_(printf_xml)("  <trace><text>");
65      VG_(vprintf_xml)(format, vargs);
66      VG_(printf_xml)("</text></trace>\n");
67   } else {
68      VG_(vmessage)(Vg_UserMsg, format, vargs);
69      VG_(message)(Vg_UserMsg, "\n");
70   }
71   va_end(vargs);
72}
73
74void DRD_(trace_msg_w_bt)(const HChar* format, ...)
75{
76   va_list vargs;
77   va_start(vargs, format);
78   if (VG_(clo_xml)) {
79      VG_(printf_xml)("  <trace><text>");
80      VG_(vprintf_xml)(format, vargs);
81      VG_(printf_xml)("</text>\n");
82   } else {
83      VG_(vmessage)(Vg_UserMsg, format, vargs);
84      VG_(message)(Vg_UserMsg, "\n");
85   }
86   VG_(get_and_pp_StackTrace)(VG_(get_running_tid)(), VG_(clo_backtrace_size));
87   va_end(vargs);
88   if (VG_(clo_xml))
89      VG_(printf_xml)("  </trace>\n");
90}
91
92/**
93 * Emit error message detail in the format requested by the user.
94 */
95static void print_err_detail(const HChar* format, ...) PRINTF_CHECK(1, 2);
96static void print_err_detail(const HChar* format, ...)
97{
98   va_list vargs;
99   va_start(vargs, format);
100   if (VG_(clo_xml))
101      VG_(vprintf_xml)(format, vargs);
102   else
103      VG_(vmessage)(Vg_UserMsg, format, vargs);
104   va_end(vargs);
105}
106
107/**
108 * Describe the client address a as good as possible, putting the result in ai.
109 */
110static
111void describe_malloced_addr(Addr const a, AddrInfo* const ai)
112{
113   Addr heap_block_start;
114
115   if (DRD_(heap_addrinfo)(a, &heap_block_start, &ai->size, &ai->lastchange))
116   {
117      ai->akind = eMallocd;
118      ai->rwoffset = a - heap_block_start;
119   }
120   else
121   {
122      ai->akind = eUnknown;
123   }
124}
125
126/**
127 * Report where a client synchronization object has been observed for the first
128 * time. The printed call stack will either refer to a pthread_*_init() or a
129 * pthread_*lock() call.
130 */
131static void first_observed(const Addr obj)
132{
133   DrdClientobj* cl;
134
135   cl = DRD_(clientobj_get_any)(obj);
136   if (cl) {
137      tl_assert(cl->any.first_observed_at);
138      if (VG_(clo_xml)) {
139         print_err_detail("  <first_observed_at>\n"
140                          "    <what>%pS</what>\n"
141                          "    <address>0x%lx</address>\n",
142                          DRD_(clientobj_type_name)(cl->any.type), obj);
143         VG_(pp_ExeContext)(cl->any.first_observed_at);
144         print_err_detail("  </first_observed_at>\n");
145      } else {
146         print_err_detail("%s 0x%lx was first observed at:\n",
147                          DRD_(clientobj_type_name)(cl->any.type), obj);
148         VG_(pp_ExeContext)(cl->any.first_observed_at);
149      }
150   }
151}
152
153static
154void drd_report_data_race(const Error* const err,
155                          const DataRaceErrInfo* const dri)
156{
157   const Bool xml = VG_(clo_xml);
158   const HChar* const what_prefix = xml ? "  <what>" : "";
159   const HChar* const what_suffix = xml ? "</what>" : "";
160   const HChar* const auxwhat_prefix = xml ? "  <auxwhat>" : "";
161   const HChar* const auxwhat_suffix = xml ? "</auxwhat>" : "";
162   const HChar* const indent = xml ? "  " : "";
163   AddrInfo ai;
164
165   XArray* /* of HChar */ descr1
166      = VG_(newXA)( VG_(malloc), "drd.error.drdr2.1",
167                    VG_(free), sizeof(HChar) );
168   XArray* /* of HChar */ descr2
169      = VG_(newXA)( VG_(malloc), "drd.error.drdr2.2",
170                    VG_(free), sizeof(HChar) );
171
172   tl_assert(dri);
173   tl_assert(dri->addr);
174   tl_assert(dri->size > 0);
175
176   (void) VG_(get_data_description)(descr1, descr2, dri->addr);
177   /* If there's nothing in descr1/2, free them.  Why is it safe to to
178      VG_(indexXA) at zero here?  Because VG_(get_data_description)
179      guarantees to zero terminate descr1/2 regardless of the outcome
180      of the call.  So there's always at least one element in each XA
181      after the call.
182   */
183   if (0 == VG_(strlen)( VG_(indexXA)( descr1, 0 ))) {
184      VG_(deleteXA)( descr1 );
185      descr1 = NULL;
186   }
187   if (0 == VG_(strlen)( VG_(indexXA)( descr2, 0 ))) {
188      VG_(deleteXA)( descr2 );
189      descr2 = NULL;
190   }
191   /* Assume (assert) that VG_(get_data_description) fills in descr1
192      before it fills in descr2 */
193   if (descr1 == NULL)
194      tl_assert(descr2 == NULL);
195   /* So anyway.  Do we have something useful? */
196   if (descr1 == NULL)
197   {
198      /* No.  Do Plan B. */
199      describe_malloced_addr(dri->addr, &ai);
200   }
201
202   print_err_detail("%sConflicting %s by thread %d at 0x%08lx size %ld%s\n",
203                    what_prefix, dri->access_type == eStore ? "store" : "load",
204                    dri->tid, dri->addr, dri->size, what_suffix);
205
206   VG_(pp_ExeContext)(VG_(get_error_where)(err));
207   if (descr1 != NULL) {
208      print_err_detail("%s%s\n", indent, (HChar*)VG_(indexXA)(descr1, 0));
209      if (descr2 != NULL)
210         print_err_detail("%s%s\n", indent, (HChar*)VG_(indexXA)(descr2, 0));
211   } else if (ai.akind == eMallocd && ai.lastchange) {
212      print_err_detail("%sAddress 0x%lx is at offset %ld from 0x%lx.%s%s",
213                       auxwhat_prefix, dri->addr, ai.rwoffset,
214                       dri->addr - ai.rwoffset, auxwhat_suffix,
215                       xml ? "\n" : "");
216      if (xml)
217         print_err_detail("  <allocation_context>\n");
218      else
219         print_err_detail(" Allocation context:\n");
220      VG_(pp_ExeContext)(ai.lastchange);
221      if (xml)
222         print_err_detail("  </allocation_context>\n");
223   } else {
224      const HChar *sect_name;
225      VgSectKind sect_kind;
226
227      sect_kind = VG_(DebugInfo_sect_kind)(&sect_name, dri->addr);
228      if (sect_kind != Vg_SectUnknown) {
229         print_err_detail("%sAllocation context: %ps section of %ps%s\n",
230                          auxwhat_prefix, VG_(pp_SectKind)(sect_kind),
231                          sect_name, auxwhat_suffix);
232      } else {
233         print_err_detail("%sAllocation context: unknown.%s\n",
234                          auxwhat_prefix, auxwhat_suffix);
235      }
236   }
237   if (s_show_conflicting_segments)
238   {
239      DRD_(thread_report_conflicting_segments)(dri->tid,
240                                               dri->addr, dri->size,
241                                               dri->access_type);
242   }
243
244   if (descr2)
245      VG_(deleteXA)(descr2);
246   if (descr1)
247      VG_(deleteXA)(descr1);
248}
249
250/**
251 * Compare two error contexts. The core function VG_(maybe_record_error)()
252 * calls this function to compare error contexts such that errors that occur
253 * repeatedly are only printed once. This function is only called by the core
254 * if the error kind of e1 and e2 matches and if the ExeContext's of e1 and
255 * e2 also match.
256 */
257static Bool drd_compare_error_contexts(VgRes res, const Error* e1,
258                                       const Error* e2)
259{
260   tl_assert(VG_(get_error_kind)(e1) == VG_(get_error_kind)(e2));
261
262   switch (VG_(get_error_kind)(e1))
263   {
264   case DataRaceErr:
265   {
266      const DataRaceErrInfo* const dri1 = VG_(get_error_extra)(e1);
267      const DataRaceErrInfo* const dri2 = VG_(get_error_extra)(e2);
268      return dri1->access_type == dri2->access_type
269	     && dri1->size == dri2->size;
270   }
271   case MutexErr:
272   {
273      const MutexErrInfo* const mei1 = VG_(get_error_extra)(e1);
274      const MutexErrInfo* const mei2 = VG_(get_error_extra)(e2);
275      return mei1->mutex == mei2->mutex;
276   }
277   default:
278      return True;
279   }
280}
281
282/**
283 * Called by the core just before an error message will be printed. Used by
284 * DRD to print the thread number as a preamble.
285 */
286static void drd_tool_error_before_pp(const Error* const e)
287{
288   static DrdThreadId s_last_tid_printed = 1;
289   DrdThreadId* err_extra;
290
291   err_extra = VG_(get_error_extra)(e);
292
293   if (err_extra && *err_extra != s_last_tid_printed && !VG_(clo_xml)) {
294      VG_(umsg)("%s:\n", DRD_(thread_get_name)(*err_extra));
295      s_last_tid_printed = *err_extra;
296   }
297}
298
299/** Report an error to the user. */
300static void drd_tool_error_pp(const Error* const e)
301{
302   const Bool xml = VG_(clo_xml);
303   const HChar* const what_prefix = xml ? "  <what>" : "";
304   const HChar* const what_suffix = xml ? "</what>" : "";
305
306   if (xml)
307      VG_(printf_xml)( "  <kind>%pS</kind>\n", drd_get_error_name(e));
308
309   switch (VG_(get_error_kind)(e))
310   {
311   case DataRaceErr: {
312      drd_report_data_race(e, VG_(get_error_extra)(e));
313      break;
314   }
315   case MutexErr: {
316      MutexErrInfo* p = (MutexErrInfo*)(VG_(get_error_extra)(e));
317      tl_assert(p);
318      if (p->recursion_count >= 0) {
319         print_err_detail("%s%s: mutex 0x%lx, recursion count %d, owner %d."
320                          "%s\n", what_prefix, VG_(get_error_string)(e),
321                          p->mutex, p->recursion_count, p->owner, what_suffix);
322      } else {
323         print_err_detail("%sThe object at address 0x%lx is not a mutex.%s\n",
324                          what_prefix, p->mutex, what_suffix);
325      }
326      VG_(pp_ExeContext)(VG_(get_error_where)(e));
327      first_observed(p->mutex);
328      break;
329   }
330   case CondErr: {
331      CondErrInfo* cdei =(CondErrInfo*)(VG_(get_error_extra)(e));
332      print_err_detail("%s%s: cond 0x%lx%s\n", what_prefix,
333                       VG_(get_error_string)(e), cdei->cond, what_suffix);
334      VG_(pp_ExeContext)(VG_(get_error_where)(e));
335      first_observed(cdei->cond);
336      break;
337   }
338   case CondDestrErr: {
339      CondDestrErrInfo* cdi = (CondDestrErrInfo*)(VG_(get_error_extra)(e));
340      print_err_detail("%s%s: cond 0x%lx, mutex 0x%lx locked by thread %d%s\n",
341                       what_prefix, VG_(get_error_string)(e), cdi->cond,
342                       cdi->mutex, cdi->owner, what_suffix);
343      VG_(pp_ExeContext)(VG_(get_error_where)(e));
344      first_observed(cdi->mutex);
345      break;
346   }
347   case CondRaceErr: {
348      CondRaceErrInfo* cei = (CondRaceErrInfo*)(VG_(get_error_extra)(e));
349      print_err_detail("%sProbably a race condition: condition variable 0x%lx"
350                       " has been signaled but the associated mutex 0x%lx is"
351                       " not locked by the signalling thread.%s\n",
352                       what_prefix, cei->cond, cei->mutex, what_suffix);
353      VG_(pp_ExeContext)(VG_(get_error_where)(e));
354      first_observed(cei->cond);
355      first_observed(cei->mutex);
356      break;
357   }
358   case CondWaitErr: {
359      CondWaitErrInfo* cwei = (CondWaitErrInfo*)(VG_(get_error_extra)(e));
360      print_err_detail("%s%s: condition variable 0x%lx, mutexes 0x%lx and"
361                       " 0x%lx%s\n", what_prefix, VG_(get_error_string)(e),
362                       cwei->cond, cwei->mutex1, cwei->mutex2, what_suffix);
363      VG_(pp_ExeContext)(VG_(get_error_where)(e));
364      first_observed(cwei->cond);
365      first_observed(cwei->mutex1);
366      first_observed(cwei->mutex2);
367      break;
368   }
369   case SemaphoreErr: {
370      SemaphoreErrInfo* sei = (SemaphoreErrInfo*)(VG_(get_error_extra)(e));
371      tl_assert(sei);
372      print_err_detail("%s%s: semaphore 0x%lx%s\n", what_prefix,
373                       VG_(get_error_string)(e), sei->semaphore, what_suffix);
374      VG_(pp_ExeContext)(VG_(get_error_where)(e));
375      first_observed(sei->semaphore);
376      break;
377   }
378   case BarrierErr: {
379      BarrierErrInfo* bei = (BarrierErrInfo*)(VG_(get_error_extra)(e));
380      tl_assert(bei);
381      print_err_detail("%s%s: barrier 0x%lx%s\n", what_prefix,
382                       VG_(get_error_string)(e), bei->barrier, what_suffix);
383      VG_(pp_ExeContext)(VG_(get_error_where)(e));
384      if (bei->other_context) {
385         if (xml)
386            print_err_detail("  <confl_wait_call>\n");
387         print_err_detail("%sConflicting wait call by thread %d:%s\n",
388                          what_prefix, bei->other_tid, what_suffix);
389         VG_(pp_ExeContext)(bei->other_context);
390         if (xml)
391            print_err_detail("  </confl_wait_call>\n");
392      }
393      first_observed(bei->barrier);
394      break;
395   }
396   case RwlockErr: {
397      RwlockErrInfo* p = (RwlockErrInfo*)(VG_(get_error_extra)(e));
398      tl_assert(p);
399      print_err_detail("%s%s: rwlock 0x%lx.%s\n", what_prefix,
400                       VG_(get_error_string)(e), p->rwlock, what_suffix);
401      VG_(pp_ExeContext)(VG_(get_error_where)(e));
402      first_observed(p->rwlock);
403      break;
404   }
405   case HoldtimeErr: {
406      HoldtimeErrInfo* p =(HoldtimeErrInfo*)(VG_(get_error_extra)(e));
407      tl_assert(p);
408      tl_assert(p->acquired_at);
409      if (xml)
410         print_err_detail("  <acquired_at>\n");
411      else
412         print_err_detail("Acquired at:\n");
413      VG_(pp_ExeContext)(p->acquired_at);
414      if (xml)
415         print_err_detail("  </acquired_at>\n");
416      print_err_detail("%sLock on %s 0x%lx was held during %d ms"
417                       " (threshold: %d ms).%s\n", what_prefix,
418                       VG_(get_error_string)(e), p->synchronization_object,
419                       p->hold_time_ms, p->threshold_ms, what_suffix);
420      VG_(pp_ExeContext)(VG_(get_error_where)(e));
421      first_observed(p->synchronization_object);
422      break;
423   }
424   case GenericErr: {
425      GenericErrInfo* gei = (GenericErrInfo*)(VG_(get_error_extra)(e));
426      print_err_detail("%s%s%s\n", what_prefix, VG_(get_error_string)(e),
427                       what_suffix);
428      VG_(pp_ExeContext)(VG_(get_error_where)(e));
429      if (gei->addr)
430	 first_observed(gei->addr);
431      break;
432   }
433   case InvalidThreadId: {
434      InvalidThreadIdInfo* iti =(InvalidThreadIdInfo*)(VG_(get_error_extra)(e));
435      print_err_detail("%s%s 0x%llx%s\n", what_prefix, VG_(get_error_string)(e),
436                       iti->ptid, what_suffix);
437      VG_(pp_ExeContext)(VG_(get_error_where)(e));
438      break;
439   }
440   case UnimpHgClReq: {
441      UnimpClReqInfo* uicr =(UnimpClReqInfo*)(VG_(get_error_extra)(e));
442      print_err_detail("%sThe annotation macro %s has not yet been implemented"
443                       " in %ps%s\n", what_prefix, uicr->descr,
444                       "<valgrind/helgrind.h>", what_suffix);
445      VG_(pp_ExeContext)(VG_(get_error_where)(e));
446      break;
447   }
448   case UnimpDrdClReq: {
449      UnimpClReqInfo* uicr =(UnimpClReqInfo*)(VG_(get_error_extra)(e));
450      print_err_detail("%sThe annotation macro %s has not yet been implemented"
451                       " in %ps%s\n", what_prefix, uicr->descr,
452                       "<valgrind/drd.h>", what_suffix);
453      VG_(pp_ExeContext)(VG_(get_error_where)(e));
454      break;
455   }
456   default:
457      print_err_detail("%s%s%s\n", what_prefix, VG_(get_error_string)(e),
458                       what_suffix);
459      VG_(pp_ExeContext)(VG_(get_error_where)(e));
460      break;
461   }
462}
463
464static UInt drd_tool_error_update_extra(const Error* e)
465{
466   switch (VG_(get_error_kind)(e))
467   {
468   case DataRaceErr:
469      return sizeof(DataRaceErrInfo);
470   case MutexErr:
471      return sizeof(MutexErrInfo);
472   case CondErr:
473      return sizeof(CondErrInfo);
474   case CondDestrErr:
475      return sizeof(CondDestrErrInfo);
476   case CondRaceErr:
477      return sizeof(CondRaceErrInfo);
478   case CondWaitErr:
479      return sizeof(CondWaitErrInfo);
480   case SemaphoreErr:
481      return sizeof(SemaphoreErrInfo);
482   case BarrierErr:
483      return sizeof(BarrierErrInfo);
484   case RwlockErr:
485      return sizeof(RwlockErrInfo);
486   case HoldtimeErr:
487      return sizeof(HoldtimeErrInfo);
488   case GenericErr:
489      return sizeof(GenericErrInfo);
490   case InvalidThreadId:
491      return sizeof(InvalidThreadIdInfo);
492   case UnimpHgClReq:
493      return sizeof(UnimpClReqInfo);
494   case UnimpDrdClReq:
495      return sizeof(UnimpClReqInfo);
496   default:
497      tl_assert(False);
498      break;
499   }
500}
501
502/**
503 * Parse suppression name.
504 *
505 * The suppression types recognized by DRD are the same types as the error
506 * types supported by DRD. So try to match the suppression name against the
507 * names of DRD error types.
508 */
509static Bool drd_is_recognized_suppression(const HChar* const name,
510                                          Supp* const supp)
511{
512   DrdErrorKind skind = 0;
513
514   if (VG_(strcmp)(name, STR_DataRaceErr) == 0)
515      skind = DataRaceErr;
516   else if (VG_(strcmp)(name, STR_MutexErr) == 0)
517      skind = MutexErr;
518   else if (VG_(strcmp)(name, STR_CondErr) == 0)
519      skind = CondErr;
520   else if (VG_(strcmp)(name, STR_CondDestrErr) == 0)
521      skind = CondDestrErr;
522   else if (VG_(strcmp)(name, STR_CondRaceErr) == 0)
523      skind = CondRaceErr;
524   else if (VG_(strcmp)(name, STR_CondWaitErr) == 0)
525      skind = CondWaitErr;
526   else if (VG_(strcmp)(name, STR_SemaphoreErr) == 0)
527      skind = SemaphoreErr;
528   else if (VG_(strcmp)(name, STR_BarrierErr) == 0)
529      skind = BarrierErr;
530   else if (VG_(strcmp)(name, STR_RwlockErr) == 0)
531      skind = RwlockErr;
532   else if (VG_(strcmp)(name, STR_HoldtimeErr) == 0)
533      skind = HoldtimeErr;
534   else if (VG_(strcmp)(name, STR_GenericErr) == 0)
535      skind = GenericErr;
536   else if (VG_(strcmp)(name, STR_InvalidThreadId) == 0)
537      skind = InvalidThreadId;
538   else if (VG_(strcmp)(name, STR_UnimpHgClReq) == 0)
539      skind = UnimpHgClReq;
540   else if (VG_(strcmp)(name, STR_UnimpDrdClReq) == 0)
541      skind = UnimpDrdClReq;
542   else
543      return False;
544
545   VG_(set_supp_kind)(supp, skind);
546   return True;
547}
548
549/**
550 * Read additional suppression information from the suppression file.
551 *
552 * None of the suppression patterns recognized by DRD has 'extra' lines
553 * of information in the suppression file, so just return True to indicate
554 * that reading the 'extra' lines succeeded.
555 */
556static
557Bool drd_read_extra_suppression_info(Int fd, HChar** bufpp,
558                                     SizeT* nBufp, Int* lineno, Supp* supp)
559{
560   return True;
561}
562
563/**
564 * Determine whether or not the types of the given error message and the
565 * given suppression match.
566 */
567static Bool drd_error_matches_suppression(const Error* const e,
568                                          const Supp* const supp)
569{
570   return VG_(get_supp_kind)(supp) == VG_(get_error_kind)(e);
571}
572
573static const HChar* drd_get_error_name(const Error* e)
574{
575   switch (VG_(get_error_kind)(e))
576   {
577   case DataRaceErr:  return VGAPPEND(STR_, DataRaceErr);
578   case MutexErr:     return VGAPPEND(STR_, MutexErr);
579   case CondErr:      return VGAPPEND(STR_, CondErr);
580   case CondDestrErr: return VGAPPEND(STR_, CondDestrErr);
581   case CondRaceErr:  return VGAPPEND(STR_, CondRaceErr);
582   case CondWaitErr:  return VGAPPEND(STR_, CondWaitErr);
583   case SemaphoreErr: return VGAPPEND(STR_, SemaphoreErr);
584   case BarrierErr:   return VGAPPEND(STR_, BarrierErr);
585   case RwlockErr:    return VGAPPEND(STR_, RwlockErr);
586   case HoldtimeErr:  return VGAPPEND(STR_, HoldtimeErr);
587   case GenericErr:   return VGAPPEND(STR_, GenericErr);
588   case InvalidThreadId: return VGAPPEND(STR_, InvalidThreadId);
589   case UnimpHgClReq:  return VGAPPEND(STR_, UnimpHgClReq);
590   case UnimpDrdClReq: return VGAPPEND(STR_, UnimpDrdClReq);
591   default:
592      tl_assert(0);
593   }
594   return 0;
595}
596
597/**
598 * Return extra suppression information.
599 *
600 * Invoked while printing a suppression pattern because the user
601 * specified --gen-suppressions=yes or all on the command line. DRD does not
602 * define any 'extra' suppression information.
603 */
604static
605SizeT drd_get_extra_suppression_info(const Error* e,
606                                     /*OUT*/HChar* buf, Int nBuf)
607{
608   tl_assert(nBuf >= 1);
609   buf[0] = '\0';
610   return 0;
611}
612
613static
614SizeT drd_print_extra_suppression_use(const Supp* su,
615                                      /*OUT*/HChar* buf, Int nBuf)
616{
617   tl_assert(nBuf >= 1);
618   buf[0] = '\0';
619   return 0;
620}
621
622static
623void  drd_update_extra_suppresion_use(const Error* e, const Supp* supp)
624{
625   return;
626}
627
628/** Tell the Valgrind core about DRD's error handlers. */
629void DRD_(register_error_handlers)(void)
630{
631   VG_(needs_tool_errors)(drd_compare_error_contexts,
632                          drd_tool_error_before_pp,
633                          drd_tool_error_pp,
634                          False,
635                          drd_tool_error_update_extra,
636                          drd_is_recognized_suppression,
637                          drd_read_extra_suppression_info,
638                          drd_error_matches_suppression,
639                          drd_get_error_name,
640                          drd_get_extra_suppression_info,
641                          drd_print_extra_suppression_use,
642                          drd_update_extra_suppresion_use);
643}
644