server/debugger.c

   1 /*
   2  * Server-side debugger functions
   3  *
   4  * Copyright (C) 1999 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "config.h"
  22 #include "wine/port.h"
  23
  24 #include <assert.h>
  25 #include <signal.h>
  26 #include <string.h>
  27 #include <stdarg.h>
  28 #include <stdio.h>
  29
  30 #include "ntstatus.h"
  31 #define WIN32_NO_STATUS
  32 #include "windef.h"
  33 #include "winternl.h"
  34
  35 #include "handle.h"
  36 #include "process.h"
  37 #include "thread.h"
  38 #include "request.h"
  39 #include "console.h"
  40
  41 enum debug_event_state { EVENT_QUEUED, EVENT_SENT, EVENT_CONTINUED };
  42
  43 /* debug event */
  44 struct debug_event
  45 {
  46     struct object          obj;       /* object header */
  47     struct list            entry;     /* entry in event queue */
  48     struct thread         *sender;    /* thread which sent this event */
  49     struct thread         *debugger;  /* debugger thread receiving the event */
  50     enum debug_event_state state;     /* event state */
  51     int                    status;    /* continuation status */
  52     debug_event_t          data;      /* event data */
  53     CONTEXT                context;   /* register context */
  54 };
  55
  56 /* debug context */
  57 struct debug_ctx
  58 {
  59     struct object        obj;         /* object header */
  60     struct list          event_queue; /* pending events queue */
  61     int                  kill_on_exit;/* kill debuggees on debugger exit ? */
  62 };
  63
  64
  65 static void debug_event_dump( struct object *obj, int verbose );
  66 static int debug_event_signaled( struct object *obj, struct thread *thread );
  67 static void debug_event_destroy( struct object *obj );
  68
  69 static const struct object_ops debug_event_ops =
  70 {
  71     sizeof(struct debug_event),    /* size */
  72     debug_event_dump,              /* dump */
  73     add_queue,                     /* add_queue */
  74     remove_queue,                  /* remove_queue */
  75     debug_event_signaled,          /* signaled */
  76     no_satisfied,                  /* satisfied */
  77     no_signal,                     /* signal */
  78     no_get_fd,                     /* get_fd */
  79     no_lookup_name,                /* lookup_name */
  80     no_close_handle,               /* close_handle */
  81     debug_event_destroy            /* destroy */
  82 };
  83
  84 static void debug_ctx_dump( struct object *obj, int verbose );
  85 static int debug_ctx_signaled( struct object *obj, struct thread *thread );
  86 static void debug_ctx_destroy( struct object *obj );
  87
  88 static const struct object_ops debug_ctx_ops =
  89 {
  90     sizeof(struct debug_ctx),      /* size */
  91     debug_ctx_dump,                /* dump */
  92     add_queue,                     /* add_queue */
  93     remove_queue,                  /* remove_queue */
  94     debug_ctx_signaled,            /* signaled */
  95     no_satisfied,                  /* satisfied */
  96     no_signal,                     /* signal */
  97     no_get_fd,                     /* get_fd */
  98     no_lookup_name,                /* lookup_name */
  99     no_close_handle,               /* close_handle */
 100     debug_ctx_destroy              /* destroy */
 101 };
 102
 103
 104 /* routines to build an event according to its type */
 105
 106 static int fill_exception_event( struct debug_event *event, void *arg )
 107 {
 108     memcpy( &event->data.info.exception, arg, sizeof(event->data.info.exception) );
 109     return 1;
 110 }
 111
 112 static int fill_create_thread_event( struct debug_event *event, void *arg )
 113 {
 114     struct process *debugger = event->debugger->process;
 115     struct thread *thread = event->sender;
 116     obj_handle_t handle;
 117
 118     /* documented: THREAD_GET_CONTEXT | THREAD_SET_CONTEXT | THREAD_SUSPEND_RESUME */
 119     if (!(handle = alloc_handle( debugger, thread, THREAD_ALL_ACCESS, FALSE ))) return 0;
 120     event->data.info.create_thread.handle = handle;
 121     event->data.info.create_thread.teb    = thread->teb;
 122     event->data.info.create_thread.start  = arg;
 123     return 1;
 124 }
 125
 126 static int fill_create_process_event( struct debug_event *event, void *arg )
 127 {
 128     struct process *debugger = event->debugger->process;
 129     struct thread *thread = event->sender;
 130     struct process *process = thread->process;
 131     obj_handle_t handle;
 132
 133     /* documented: PROCESS_VM_READ | PROCESS_VM_WRITE */
 134     if (!(handle = alloc_handle( debugger, process, PROCESS_ALL_ACCESS, FALSE ))) return 0;
 135     event->data.info.create_process.process = handle;
 136
 137     /* documented: THREAD_GET_CONTEXT | THREAD_SET_CONTEXT | THREAD_SUSPEND_RESUME */
 138     if (!(handle = alloc_handle( debugger, thread, THREAD_ALL_ACCESS, FALSE )))
 139     {
 140         close_handle( debugger, event->data.info.create_process.process, NULL );
 141         return 0;
 142     }
 143     event->data.info.create_process.thread = handle;
 144
 145     handle = 0;
 146     if (process->exe.file &&
 147         /* the doc says write access too, but this doesn't seem a good idea */
 148         !(handle = alloc_handle( debugger, process->exe.file, GENERIC_READ, FALSE )))
 149     {
 150         close_handle( debugger, event->data.info.create_process.process, NULL );
 151         close_handle( debugger, event->data.info.create_process.thread, NULL );
 152         return 0;
 153     }
 154     event->data.info.create_process.file       = handle;
 155     event->data.info.create_process.teb        = thread->teb;
 156     event->data.info.create_process.base       = process->exe.base;
 157     event->data.info.create_process.start      = arg;
 158     event->data.info.create_process.dbg_offset = process->exe.dbg_offset;
 159     event->data.info.create_process.dbg_size   = process->exe.dbg_size;
 160     event->data.info.create_process.name       = process->exe.name;
 161     event->data.info.create_process.unicode    = 1;
 162     return 1;
 163 }
 164
 165 static int fill_exit_thread_event( struct debug_event *event, void *arg )
 166 {
 167     struct thread *thread = arg;
 168     event->data.info.exit.exit_code = thread->exit_code;
 169     return 1;
 170 }
 171
 172 static int fill_exit_process_event( struct debug_event *event, void *arg )
 173 {
 174     struct process *process = arg;
 175     event->data.info.exit.exit_code = process->exit_code;
 176     return 1;
 177 }
 178
 179 static int fill_load_dll_event( struct debug_event *event, void *arg )
 180 {
 181     struct process *debugger = event->debugger->process;
 182     struct process_dll *dll = arg;
 183     obj_handle_t handle = 0;
 184
 185     if (dll->file && !(handle = alloc_handle( debugger, dll->file, GENERIC_READ, FALSE )))
 186         return 0;
 187     event->data.info.load_dll.handle     = handle;
 188     event->data.info.load_dll.base       = dll->base;
 189     event->data.info.load_dll.dbg_offset = dll->dbg_offset;
 190     event->data.info.load_dll.dbg_size   = dll->dbg_size;
 191     event->data.info.load_dll.name       = dll->name;
 192     event->data.info.load_dll.unicode    = 1;
 193     return 1;
 194 }
 195
 196 static int fill_unload_dll_event( struct debug_event *event, void *arg )
 197 {
 198     event->data.info.unload_dll.base = arg;
 199     return 1;
 200 }
 201
 202 static int fill_output_debug_string_event( struct debug_event *event, void *arg )
 203 {
 204     struct debug_event_output_string *data = arg;
 205     event->data.info.output_string = *data;
 206     return 1;
 207 }
 208
 209 typedef int (*fill_event_func)( struct debug_event *event, void *arg );
 210
 211 #define NB_DEBUG_EVENTS OUTPUT_DEBUG_STRING_EVENT  /* RIP_EVENT not supported */
 212
 213 static const fill_event_func fill_debug_event[NB_DEBUG_EVENTS] =
 214 {
 215     fill_exception_event,            /* EXCEPTION_DEBUG_EVENT */
 216     fill_create_thread_event,        /* CREATE_THREAD_DEBUG_EVENT */
 217     fill_create_process_event,       /* CREATE_PROCESS_DEBUG_EVENT */
 218     fill_exit_thread_event,          /* EXIT_THREAD_DEBUG_EVENT */
 219     fill_exit_process_event,         /* EXIT_PROCESS_DEBUG_EVENT */
 220     fill_load_dll_event,             /* LOAD_DLL_DEBUG_EVENT */
 221     fill_unload_dll_event,           /* UNLOAD_DLL_DEBUG_EVENT */
 222     fill_output_debug_string_event   /* OUTPUT_DEBUG_STRING_EVENT */
 223 };
 224
 225
 226 /* unlink the first event from the queue */
 227 static void unlink_event( struct debug_ctx *debug_ctx, struct debug_event *event )
 228 {
 229     list_remove( &event->entry );
 230     if (event->sender->debug_event == event) event->sender->debug_event = NULL;
 231     release_object( event );
 232 }
 233
 234 /* link an event at the end of the queue */
 235 static void link_event( struct debug_event *event )
 236 {
 237     struct debug_ctx *debug_ctx = event->debugger->debug_ctx;
 238
 239     assert( debug_ctx );
 240     grab_object( event );
 241     list_add_tail( &debug_ctx->event_queue, &event->entry );
 242     if (!event->sender->debug_event) wake_up( &debug_ctx->obj, 0 );
 243 }
 244
 245 /* find the next event that we can send to the debugger */
 246 static struct debug_event *find_event_to_send( struct debug_ctx *debug_ctx )
 247 {
 248     struct debug_event *event;
 249
 250     LIST_FOR_EACH_ENTRY( event, &debug_ctx->event_queue, struct debug_event, entry )
 251     {
 252         if (event->state == EVENT_SENT) continue;  /* already sent */
 253         if (event->sender->debug_event) continue;  /* thread busy with another one */
 254         return event;
 255     }
 256     return NULL;
 257 }
 258
 259 static void debug_event_dump( struct object *obj, int verbose )
 260 {
 261     struct debug_event *debug_event = (struct debug_event *)obj;
 262     assert( obj->ops == &debug_event_ops );
 263     fprintf( stderr, "Debug event sender=%p code=%d state=%d\n",
 264              debug_event->sender, debug_event->data.code, debug_event->state );
 265 }
 266
 267 static int debug_event_signaled( struct object *obj, struct thread *thread )
 268 {
 269     struct debug_event *debug_event = (struct debug_event *)obj;
 270     assert( obj->ops == &debug_event_ops );
 271     return debug_event->state == EVENT_CONTINUED;
 272 }
 273
 274 static void debug_event_destroy( struct object *obj )
 275 {
 276     struct debug_event *event = (struct debug_event *)obj;
 277     assert( obj->ops == &debug_event_ops );
 278
 279     /* If the event has been sent already, the handles are now under the */
 280     /* responsibility of the debugger process, so we don't touch them    */
 281     if (event->state == EVENT_QUEUED)
 282     {
 283         struct process *debugger = event->debugger->process;
 284         switch(event->data.code)
 285         {
 286         case CREATE_THREAD_DEBUG_EVENT:
 287             close_handle( debugger, event->data.info.create_thread.handle, NULL );
 288             break;
 289         case CREATE_PROCESS_DEBUG_EVENT:
 290             if (event->data.info.create_process.file)
 291                 close_handle( debugger, event->data.info.create_process.file, NULL );
 292             close_handle( debugger, event->data.info.create_process.thread, NULL );
 293             close_handle( debugger, event->data.info.create_process.process, NULL );
 294             break;
 295         case LOAD_DLL_DEBUG_EVENT:
 296             if (event->data.info.load_dll.handle)
 297                 close_handle( debugger, event->data.info.load_dll.handle, NULL );
 298             break;
 299         }
 300     }
 301     if (event->sender->context == &event->context) event->sender->context = NULL;
 302     release_object( event->sender );
 303     release_object( event->debugger );
 304 }
 305
 306 static void debug_ctx_dump( struct object *obj, int verbose )
 307 {
 308     struct debug_ctx *debug_ctx = (struct debug_ctx *)obj;
 309     assert( obj->ops == &debug_ctx_ops );
 310     fprintf( stderr, "Debug context head=%p tail=%p\n",
 311              debug_ctx->event_queue.next, debug_ctx->event_queue.prev );
 312 }
 313
 314 static int debug_ctx_signaled( struct object *obj, struct thread *thread )
 315 {
 316     struct debug_ctx *debug_ctx = (struct debug_ctx *)obj;
 317     assert( obj->ops == &debug_ctx_ops );
 318     return find_event_to_send( debug_ctx ) != NULL;
 319 }
 320
 321 static void debug_ctx_destroy( struct object *obj )
 322 {
 323     struct list *ptr;
 324     struct debug_ctx *debug_ctx = (struct debug_ctx *)obj;
 325     assert( obj->ops == &debug_ctx_ops );
 326
 327     /* free all pending events */
 328     while ((ptr = list_head( &debug_ctx->event_queue )))
 329         unlink_event( debug_ctx, LIST_ENTRY( ptr, struct debug_event, entry ));
 330 }
 331
 332 /* continue a debug event */
 333 static int continue_debug_event( struct process *process, struct thread *thread, int status )
 334 {
 335     struct debug_ctx *debug_ctx = current->debug_ctx;
 336
 337     if (debug_ctx && process->debugger == current && thread->process == process)
 338     {
 339         struct debug_event *event;
 340
 341         /* find the event in the queue */
 342         LIST_FOR_EACH_ENTRY( event, &debug_ctx->event_queue, struct debug_event, entry )
 343         {
 344             if (event->state != EVENT_SENT) continue;
 345             if (event->sender == thread)
 346             {
 347                 assert( event->sender->debug_event == event );
 348
 349                 event->status = status;
 350                 event->state  = EVENT_CONTINUED;
 351                 wake_up( &event->obj, 0 );
 352                 unlink_event( debug_ctx, event );
 353                 resume_process( process );
 354                 return 1;
 355             }
 356         }
 357     }
 358     /* not debugging this process, or no such event */
 359     set_error( STATUS_ACCESS_DENIED );  /* FIXME */
 360     return 0;
 361 }
 362
 363 /* alloc a debug event for a debugger */
 364 static struct debug_event *alloc_debug_event( struct thread *thread, int code,
 365                                               void *arg, const CONTEXT *context )
 366 {
 367     struct thread *debugger = thread->process->debugger;
 368     struct debug_event *event;
 369
 370     assert( code > 0 && code <= NB_DEBUG_EVENTS );
 371     /* cannot queue a debug event for myself */
 372     assert( debugger->process != thread->process );
 373
 374     /* build the event */
 375     if (!(event = alloc_object( &debug_event_ops ))) return NULL;
 376     event->state     = EVENT_QUEUED;
 377     event->sender    = (struct thread *)grab_object( thread );
 378     event->debugger  = (struct thread *)grab_object( debugger );
 379     event->data.code = code;
 380
 381     if (!fill_debug_event[code-1]( event, arg ))
 382     {
 383         event->data.code = -1;  /* make sure we don't attempt to close handles */
 384         release_object( event );
 385         return NULL;
 386     }
 387     if (context)
 388     {
 389         memcpy( &event->context, context, sizeof(event->context) );
 390         thread->context = &event->context;
 391     }
 392     return event;
 393 }
 394
 395 /* generate a debug event from inside the server and queue it */
 396 void generate_debug_event( struct thread *thread, int code, void *arg )
 397 {
 398     if (thread->process->debugger)
 399     {
 400         struct debug_event *event = alloc_debug_event( thread, code, arg, NULL );
 401         if (event)
 402         {
 403             link_event( event );
 404             suspend_process( thread->process );
 405             release_object( event );
 406         }
 407     }
 408 }
 409
 410 /* attach a process to a debugger thread and suspend it */
 411 static int debugger_attach( struct process *process, struct thread *debugger )
 412 {
 413     struct thread *thread;
 414
 415     if (process->debugger) goto error;  /* already being debugged */
 416     if (!is_process_init_done( process )) goto error;  /* still starting up */
 417     if (list_empty( &process->thread_list )) goto error;  /* no thread running in the process */
 418
 419     /* make sure we don't create a debugging loop */
 420     for (thread = debugger; thread; thread = thread->process->debugger)
 421         if (thread->process == process) goto error;
 422
 423     /* don't let a debugger debug its console... won't work */
 424     if (debugger->process->console && debugger->process->console->renderer->process == process)
 425         goto error;
 426
 427     suspend_process( process );
 428     if (!attach_process( process ) || !set_process_debugger( process, debugger ))
 429     {
 430         resume_process( process );
 431         return 0;
 432     }
 433     if (!set_process_debug_flag( process, 1 ))
 434     {
 435         process->debugger = NULL;
 436         resume_process( process );
 437         return 0;
 438     }
 439     return 1;
 440
 441  error:
 442     set_error( STATUS_ACCESS_DENIED );
 443     return 0;
 444 }
 445
 446
 447 /* detach a process from a debugger thread (and resume it ?) */
 448 int debugger_detach( struct process *process, struct thread *debugger )
 449 {
 450     struct debug_event *event;
 451     struct debug_ctx *debug_ctx;
 452
 453     if (!process->debugger || process->debugger != debugger)
 454         goto error;  /* not currently debugged, or debugged by another debugger */
 455     if (!debugger->debug_ctx ) goto error; /* should be a debugger */
 456     /* init should be done, otherwise wouldn't be attached */
 457     assert(is_process_init_done(process));
 458
 459     suspend_process( process );
 460     /* send continue indication for all events */
 461     debug_ctx = debugger->debug_ctx;
 462
 463     /* find the event in the queue
 464      * FIXME: could loop on process' threads and look the debug_event field */
 465     LIST_FOR_EACH_ENTRY( event, &debug_ctx->event_queue, struct debug_event, entry )
 466     {
 467         if (event->state != EVENT_QUEUED) continue;
 468
 469         if (event->sender->process == process)
 470         {
 471             assert( event->sender->debug_event == event );
 472             event->status = DBG_CONTINUE;
 473             event->state  = EVENT_CONTINUED;
 474             wake_up( &event->obj, 0 );
 475             unlink_event( debug_ctx, event );
 476             /* from queued debug event */
 477             resume_process( process );
 478             break;
 479         }
 480     }
 481
 482     /* remove relationships between process and its debugger */
 483     process->debugger = NULL;
 484     if (!set_process_debug_flag( process, 0 )) clear_error();  /* ignore error */
 485     detach_process( process );
 486
 487     /* from this function */
 488     resume_process( process );
 489     return 0;
 490
 491  error:
 492     set_error( STATUS_ACCESS_DENIED );
 493     return 0;
 494 }
 495
 496 /* generate all startup events of a given process */
 497 void generate_startup_debug_events( struct process *process, void *entry )
 498 {
 499     struct list *ptr;
 500     struct thread *thread, *first_thread = get_process_first_thread( process );
 501
 502     /* generate creation events */
 503     LIST_FOR_EACH_ENTRY( thread, &process->thread_list, struct thread, proc_entry )
 504     {
 505         if (thread == first_thread)
 506             generate_debug_event( thread, CREATE_PROCESS_DEBUG_EVENT, entry );
 507         else
 508             generate_debug_event( thread, CREATE_THREAD_DEBUG_EVENT, NULL );
 509     }
 510
 511     /* generate dll events (in loading order, i.e. reverse list order) */
 512     ptr = list_tail( &process->dlls );
 513     while (ptr)
 514     {
 515         struct process_dll *dll = LIST_ENTRY( ptr, struct process_dll, entry );
 516         generate_debug_event( first_thread, LOAD_DLL_DEBUG_EVENT, dll );
 517         ptr = list_prev( &process->dlls, ptr );
 518     }
 519 }
 520
 521 /* set the debugger of a given process */
 522 int set_process_debugger( struct process *process, struct thread *debugger )
 523 {
 524     struct debug_ctx *debug_ctx;
 525
 526     assert( !process->debugger );
 527
 528     if (!debugger->debug_ctx)  /* need to allocate a context */
 529     {
 530         if (!(debug_ctx = alloc_object( &debug_ctx_ops ))) return 0;
 531         debug_ctx->kill_on_exit = 1;
 532         list_init( &debug_ctx->event_queue );
 533         debugger->debug_ctx = debug_ctx;
 534     }
 535     process->debugger = debugger;
 536     return 1;
 537 }
 538
 539 /* a thread is exiting */
 540 void debug_exit_thread( struct thread *thread )
 541 {
 542     if (thread->debug_ctx)  /* this thread is a debugger */
 543     {
 544         if (thread->debug_ctx->kill_on_exit)
 545         {
 546             /* kill all debugged processes */
 547             kill_debugged_processes( thread, thread->exit_code );
 548         }
 549         else
 550         {
 551             detach_debugged_processes( thread );
 552         }
 553         release_object( thread->debug_ctx );
 554         thread->debug_ctx = NULL;
 555     }
 556 }
 557
 558 /* Wait for a debug event */
 559 DECL_HANDLER(wait_debug_event)
 560 {
 561     struct debug_ctx *debug_ctx = current->debug_ctx;
 562     struct debug_event *event;
 563
 564     if (!debug_ctx)  /* current thread is not a debugger */
 565     {
 566         set_error( STATUS_INVALID_HANDLE );
 567         return;
 568     }
 569     reply->wait = 0;
 570     if ((event = find_event_to_send( debug_ctx )))
 571     {
 572         size_t size = get_reply_max_size();
 573         event->state = EVENT_SENT;
 574         event->sender->debug_event = event;
 575         reply->pid = get_process_id( event->sender->process );
 576         reply->tid = get_thread_id( event->sender );
 577         if (size > sizeof(debug_event_t)) size = sizeof(debug_event_t);
 578         set_reply_data( &event->data, size );
 579     }
 580     else  /* no event ready */
 581     {
 582         reply->pid  = 0;
 583         reply->tid  = 0;
 584         if (req->get_handle)
 585             reply->wait = alloc_handle( current->process, debug_ctx, SYNCHRONIZE, FALSE );
 586     }
 587 }
 588
 589 /* Continue a debug event */
 590 DECL_HANDLER(continue_debug_event)
 591 {
 592     struct process *process = get_process_from_id( req->pid );
 593     if (process)
 594     {
 595         struct thread *thread = get_thread_from_id( req->tid );
 596         if (thread)
 597         {
 598             continue_debug_event( process, thread, req->status );
 599             release_object( thread );
 600         }
 601         release_object( process );
 602     }
 603 }
 604
 605 /* Start debugging an existing process */
 606 DECL_HANDLER(debug_process)
 607 {
 608     struct process *process = get_process_from_id( req->pid );
 609     if (!process) return;
 610
 611     if (!req->attach)
 612     {
 613         debugger_detach( process, current );
 614     }
 615     else if (debugger_attach( process, current ))
 616     {
 617         struct debug_event_exception data;
 618         struct thread *thread = get_process_first_thread( process );
 619
 620         generate_startup_debug_events( process, NULL );
 621         resume_process( process );
 622
 623         data.record.ExceptionCode    = EXCEPTION_BREAKPOINT;
 624         data.record.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 625         data.record.ExceptionRecord  = NULL;
 626         data.record.ExceptionAddress = get_thread_ip( thread );
 627         data.record.NumberParameters = 0;
 628         data.first = 1;
 629         generate_debug_event( thread, EXCEPTION_DEBUG_EVENT, &data );
 630     }
 631     release_object( process );
 632 }
 633
 634 /* queue an exception event */
 635 DECL_HANDLER(queue_exception_event)
 636 {
 637     reply->handle = 0;
 638     if (current->process->debugger)
 639     {
 640         struct debug_event_exception data;
 641         struct debug_event *event;
 642         const CONTEXT *context = get_req_data();
 643         const EXCEPTION_RECORD *rec = (const EXCEPTION_RECORD *)(context + 1);
 644
 645         if (get_req_data_size() < sizeof(*rec) + sizeof(*context))
 646         {
 647             set_error( STATUS_INVALID_PARAMETER );
 648             return;
 649         }
 650         data.record = *rec;
 651         data.first  = req->first;
 652         if ((event = alloc_debug_event( current, EXCEPTION_DEBUG_EVENT, &data, context )))
 653         {
 654             if ((reply->handle = alloc_handle( current->process, event, SYNCHRONIZE, FALSE )))
 655             {
 656                 link_event( event );
 657                 suspend_process( current->process );
 658             }
 659             release_object( event );
 660         }
 661     }
 662 }
 663
 664 /* retrieve the status of an exception event */
 665 DECL_HANDLER(get_exception_status)
 666 {
 667     struct debug_event *event;
 668
 669     if ((event = (struct debug_event *)get_handle_obj( current->process, req->handle,
 670                                                        0, &debug_event_ops )))
 671     {
 672         close_handle( current->process, req->handle, NULL );
 673         if (event->state == EVENT_CONTINUED)
 674         {
 675             if (current->context == &event->context)
 676             {
 677                 size_t size = min( sizeof(CONTEXT), get_reply_max_size() );
 678                 set_reply_data( &event->context, size );
 679                 current->context = NULL;
 680             }
 681             set_error( event->status );
 682         }
 683         else set_error( STATUS_PENDING );
 684         release_object( event );
 685     }
 686 }
 687
 688 /* send an output string to the debugger */
 689 DECL_HANDLER(output_debug_string)
 690 {
 691     struct debug_event_output_string data;
 692
 693     data.string  = req->string;
 694     data.unicode = req->unicode;
 695     data.length  = req->length;
 696     generate_debug_event( current, OUTPUT_DEBUG_STRING_EVENT, &data );
 697 }
 698
 699 /* simulate a breakpoint in a process */
 700 DECL_HANDLER(debug_break)
 701 {
 702     struct process *process;
 703
 704     reply->self = 0;
 705     if (!(process = get_process_from_handle( req->handle, PROCESS_SET_INFORMATION /*FIXME*/ )))
 706         return;
 707     if (process != current->process)
 708     {
 709         /* find a suitable thread to signal */
 710         struct thread *thread;
 711         LIST_FOR_EACH_ENTRY( thread, &process->thread_list, struct thread, proc_entry )
 712         {
 713             if (send_thread_signal( thread, SIGTRAP )) goto done;
 714         }
 715         set_error( STATUS_ACCESS_DENIED );
 716     }
 717     else reply->self = 1;
 718
 719 done:
 720     release_object( process );
 721 }
 722
 723 /* set debugger kill on exit flag */
 724 DECL_HANDLER(set_debugger_kill_on_exit)
 725 {
 726     if (!current->debug_ctx)
 727     {
 728         set_error( STATUS_ACCESS_DENIED );
 729         return;
 730     }
 731     current->debug_ctx->kill_on_exit = req->kill_on_exit;
 732 }