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