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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, 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 "file.h"
  37 #include "process.h"
  38 #include "thread.h"
  39 #include "request.h"
  40
  41 enum debug_event_state { EVENT_QUEUED, EVENT_SENT, EVENT_DELAYED, 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 file           *file;      /* file object for events that need one */
  50     enum debug_event_state state;     /* event state */
  51     int                    status;    /* continuation status */
  52     debug_event_t          data;      /* event data */
  53 };
  54
  55 /* debug object */
  56 struct debug_obj
  57 {
  58     struct object        obj;         /* object header */
  59     struct list          event_queue; /* pending events queue */
  60     unsigned int         flags;       /* debug flags */
  61 };
  62
  63
  64 static void debug_event_dump( struct object *obj, int verbose );
  65 static int debug_event_signaled( struct object *obj, struct wait_queue_entry *entry );
  66 static void debug_event_destroy( struct object *obj );
  67
  68 static const struct object_ops debug_event_ops =
  69 {
  70     sizeof(struct debug_event),    /* size */
  71     debug_event_dump,              /* dump */
  72     no_get_type,                   /* get_type */
  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_map_access,                 /* map_access */
  80     default_get_sd,                /* get_sd */
  81     default_set_sd,                /* set_sd */
  82     no_get_full_name,              /* get_full_name */
  83     no_lookup_name,                /* lookup_name */
  84     no_link_name,                  /* link_name */
  85     NULL,                          /* unlink_name */
  86     no_open_file,                  /* open_file */
  87     no_kernel_obj_list,            /* get_kernel_obj_list */
  88     no_close_handle,               /* close_handle */
  89     debug_event_destroy            /* destroy */
  90 };
  91
  92 static void debug_obj_dump( struct object *obj, int verbose );
  93 static struct object_type *debug_obj_get_type( struct object *obj );
  94 static int debug_obj_signaled( struct object *obj, struct wait_queue_entry *entry );
  95 static unsigned int debug_obj_map_access( struct object *obj, unsigned int access );
  96 static void debug_obj_destroy( struct object *obj );
  97
  98 static const struct object_ops debug_obj_ops =
  99 {
 100     sizeof(struct debug_obj),      /* size */
 101     debug_obj_dump,                /* dump */
 102     debug_obj_get_type,            /* get_type */
 103     add_queue,                     /* add_queue */
 104     remove_queue,                  /* remove_queue */
 105     debug_obj_signaled,            /* signaled */
 106     no_satisfied,                  /* satisfied */
 107     no_signal,                     /* signal */
 108     no_get_fd,                     /* get_fd */
 109     debug_obj_map_access,          /* map_access */
 110     default_get_sd,                /* get_sd */
 111     default_set_sd,                /* set_sd */
 112     default_get_full_name,         /* get_full_name */
 113     no_lookup_name,                /* lookup_name */
 114     directory_link_name,           /* link_name */
 115     default_unlink_name,           /* unlink_name */
 116     no_open_file,                  /* open_file */
 117     no_kernel_obj_list,            /* get_kernel_obj_list */
 118     no_close_handle,               /* close_handle */
 119     debug_obj_destroy              /* destroy */
 120 };
 121
 122
 123 /* routines to build an event according to its type */
 124
 125 static void fill_exception_event( struct debug_event *event, const void *arg )
 126 {
 127     const debug_event_t *data = arg;
 128     event->data.exception = data->exception;
 129     event->data.exception.nb_params = min( event->data.exception.nb_params, EXCEPTION_MAXIMUM_PARAMETERS );
 130 }
 131
 132 static void fill_create_thread_event( struct debug_event *event, const void *arg )
 133 {
 134     const client_ptr_t *entry = arg;
 135
 136     if (entry) event->data.create_thread.start = *entry;
 137 }
 138
 139 static void fill_create_process_event( struct debug_event *event, const void *arg )
 140 {
 141     const struct memory_view *view = arg;
 142     const pe_image_info_t *image_info = get_view_image_info( view, &event->data.create_process.base );
 143
 144     event->data.create_process.start      = image_info->entry_point;
 145     event->data.create_process.dbg_offset = image_info->dbg_offset;
 146     event->data.create_process.dbg_size   = image_info->dbg_size;
 147     /* the doc says write access too, but this doesn't seem a good idea */
 148     event->file = get_view_file( view, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE );
 149 }
 150
 151 static void fill_exit_thread_event( struct debug_event *event, const void *arg )
 152 {
 153     const struct thread *thread = arg;
 154     event->data.exit.exit_code = thread->exit_code;
 155 }
 156
 157 static void fill_exit_process_event( struct debug_event *event, const void *arg )
 158 {
 159     const struct process *process = arg;
 160     event->data.exit.exit_code = process->exit_code;
 161 }
 162
 163 static void fill_load_dll_event( struct debug_event *event, const void *arg )
 164 {
 165     struct process *process = event->sender->process;
 166     const struct process_dll *dll = arg;
 167     struct memory_view *view = find_mapped_view( process, dll->base );
 168     const pe_image_info_t *image_info = get_view_image_info( view, &event->data.load_dll.base );
 169
 170     event->data.load_dll.dbg_offset = image_info->dbg_offset;
 171     event->data.load_dll.dbg_size   = image_info->dbg_size;
 172     event->data.load_dll.name       = dll->name;
 173     event->file = get_view_file( view, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE );
 174 }
 175
 176 static void fill_unload_dll_event( struct debug_event *event, const void *arg )
 177 {
 178     const mod_handle_t *base = arg;
 179     event->data.unload_dll.base = *base;
 180 }
 181
 182 typedef void (*fill_event_func)( struct debug_event *event, const void *arg );
 183
 184 static const fill_event_func fill_debug_event[] =
 185 {
 186     fill_create_thread_event,  /* DbgCreateThreadStateChange */
 187     fill_create_process_event, /* DbgCreateProcessStateChange */
 188     fill_exit_thread_event,    /* DbgExitThreadStateChange */
 189     fill_exit_process_event,   /* DbgExitProcessStateChange */
 190     fill_exception_event,      /* DbgExceptionStateChange */
 191     fill_exception_event,      /* DbgBreakpointStateChange */
 192     fill_exception_event,      /* DbgSingleStepStateChange */
 193     fill_load_dll_event,       /* DbgLoadDllStateChange */
 194     fill_unload_dll_event      /* DbgUnloadDllStateChange */
 195 };
 196
 197 /* allocate the necessary handles in the event data */
 198 static void alloc_event_handles( struct debug_event *event, struct process *process )
 199 {
 200     switch (event->data.code)
 201     {
 202     case DbgCreateThreadStateChange:
 203         /* documented: THREAD_GET_CONTEXT | THREAD_SET_CONTEXT | THREAD_SUSPEND_RESUME */
 204         event->data.create_thread.handle = alloc_handle( process, event->sender, THREAD_ALL_ACCESS, 0 );
 205         break;
 206     case DbgCreateProcessStateChange:
 207         event->data.create_process.thread = alloc_handle( process, event->sender, THREAD_ALL_ACCESS, 0 );
 208         /* documented: PROCESS_VM_READ | PROCESS_VM_WRITE */
 209         event->data.create_process.process = alloc_handle( process, event->sender->process,
 210                                                            PROCESS_ALL_ACCESS, 0 );
 211         if (event->file)
 212             event->data.create_process.file = alloc_handle( process, event->file, GENERIC_READ, 0 );
 213         break;
 214     case DbgLoadDllStateChange:
 215         if (event->file)
 216             event->data.load_dll.handle = alloc_handle( process, event->file, GENERIC_READ, 0 );
 217         break;
 218     }
 219     clear_error();  /* ignore errors, simply set handles to 0 */
 220 }
 221
 222 /* unlink the first event from the queue */
 223 static void unlink_event( struct debug_obj *debug_obj, struct debug_event *event )
 224 {
 225     list_remove( &event->entry );
 226     if (event->sender->process->debug_event == event) event->sender->process->debug_event = NULL;
 227     release_object( event );
 228 }
 229
 230 /* link an event at the end of the queue */
 231 static void link_event( struct debug_obj *debug_obj, struct debug_event *event )
 232 {
 233     grab_object( event );
 234     list_add_tail( &debug_obj->event_queue, &event->entry );
 235     if (!event->sender->process->debug_event)
 236     {
 237         /* grab reference since debugger could be killed while trying to wake up */
 238         grab_object( debug_obj );
 239         wake_up( &debug_obj->obj, 0 );
 240         release_object( debug_obj );
 241     }
 242 }
 243
 244 /* resume a delayed debug event already in the queue */
 245 static void resume_event( struct debug_obj *debug_obj, struct debug_event *event )
 246 {
 247     event->state = EVENT_QUEUED;
 248     if (!event->sender->process->debug_event)
 249     {
 250         grab_object( debug_obj );
 251         wake_up( &debug_obj->obj, 0 );
 252         release_object( debug_obj );
 253     }
 254 }
 255
 256 /* delay a debug event already in the queue to be replayed when thread wakes up */
 257 static void delay_event( struct debug_obj *debug_obj, struct debug_event *event )
 258 {
 259     event->state = EVENT_DELAYED;
 260     if (event->sender->process->debug_event == event) event->sender->process->debug_event = NULL;
 261 }
 262
 263 /* find the next event that we can send to the debugger */
 264 static struct debug_event *find_event_to_send( struct debug_obj *debug_obj )
 265 {
 266     struct debug_event *event;
 267
 268     LIST_FOR_EACH_ENTRY( event, &debug_obj->event_queue, struct debug_event, entry )
 269     {
 270         if (event->state == EVENT_SENT) continue;  /* already sent */
 271         if (event->state == EVENT_DELAYED) continue;  /* delayed until thread resumes */
 272         if (event->sender->process->debug_event) continue;  /* process busy with another one */
 273         return event;
 274     }
 275     return NULL;
 276 }
 277
 278 static void debug_event_dump( struct object *obj, int verbose )
 279 {
 280     struct debug_event *debug_event = (struct debug_event *)obj;
 281     assert( obj->ops == &debug_event_ops );
 282     fprintf( stderr, "Debug event sender=%p code=%d state=%d\n",
 283              debug_event->sender, debug_event->data.code, debug_event->state );
 284 }
 285
 286 static int debug_event_signaled( struct object *obj, struct wait_queue_entry *entry )
 287 {
 288     struct debug_event *debug_event = (struct debug_event *)obj;
 289     assert( obj->ops == &debug_event_ops );
 290     return debug_event->state == EVENT_CONTINUED;
 291 }
 292
 293 static void debug_event_destroy( struct object *obj )
 294 {
 295     struct debug_event *event = (struct debug_event *)obj;
 296     assert( obj->ops == &debug_event_ops );
 297
 298     if (event->file) release_object( event->file );
 299     release_object( event->sender );
 300 }
 301
 302 static void debug_obj_dump( struct object *obj, int verbose )
 303 {
 304     struct debug_obj *debug_obj = (struct debug_obj *)obj;
 305     assert( obj->ops == &debug_obj_ops );
 306     fprintf( stderr, "Debug context head=%p tail=%p\n",
 307              debug_obj->event_queue.next, debug_obj->event_queue.prev );
 308 }
 309
 310 static struct object_type *debug_obj_get_type( struct object *obj )
 311 {
 312     static const WCHAR name[] = {'D','e','b','u','g','O','b','j','e','c','t'};
 313     static const struct unicode_str str = { name, sizeof(name) };
 314     return get_object_type( &str );
 315 }
 316
 317 static int debug_obj_signaled( struct object *obj, struct wait_queue_entry *entry )
 318 {
 319     struct debug_obj *debug_obj = (struct debug_obj *)obj;
 320     assert( obj->ops == &debug_obj_ops );
 321     return find_event_to_send( debug_obj ) != NULL;
 322 }
 323
 324 static unsigned int debug_obj_map_access( struct object *obj, unsigned int access )
 325 {
 326     if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ | DEBUG_READ_EVENT | DEBUG_QUERY_INFORMATION;
 327     if (access & GENERIC_WRITE)   access |= STANDARD_RIGHTS_WRITE | DEBUG_SET_INFORMATION;
 328     if (access & GENERIC_EXECUTE) access |= STANDARD_RIGHTS_EXECUTE | DEBUG_PROCESS_ASSIGN;
 329     if (access & GENERIC_ALL)     access |= STANDARD_RIGHTS_ALL | EVENT_QUERY_STATE | EVENT_MODIFY_STATE;
 330     return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
 331 }
 332
 333 static void debug_obj_destroy( struct object *obj )
 334 {
 335     struct list *ptr;
 336     struct debug_obj *debug_obj = (struct debug_obj *)obj;
 337     assert( obj->ops == &debug_obj_ops );
 338
 339     detach_debugged_processes( debug_obj,
 340                                (debug_obj->flags & DEBUG_KILL_ON_CLOSE) ? STATUS_DEBUGGER_INACTIVE : 0 );
 341
 342     /* free all pending events */
 343     while ((ptr = list_head( &debug_obj->event_queue )))
 344         unlink_event( debug_obj, LIST_ENTRY( ptr, struct debug_event, entry ));
 345 }
 346
 347 struct debug_obj *get_debug_obj( struct process *process, obj_handle_t handle, unsigned int access )
 348 {
 349     return (struct debug_obj *)get_handle_obj( process, handle, access, &debug_obj_ops );
 350 }
 351
 352 static struct debug_obj *create_debug_obj( struct object *root, const struct unicode_str *name,
 353                                            unsigned int attr, unsigned int flags,
 354                                            const struct security_descriptor *sd )
 355 {
 356     struct debug_obj *debug_obj;
 357
 358     if ((debug_obj = create_named_object( root, &debug_obj_ops, name, attr, sd )))
 359     {
 360         if (get_error() != STATUS_OBJECT_NAME_EXISTS)
 361         {
 362             debug_obj->flags = flags;
 363             list_init( &debug_obj->event_queue );
 364         }
 365     }
 366     return debug_obj;
 367 }
 368
 369 /* continue a debug event */
 370 static int continue_debug_event( struct debug_obj *debug_obj, struct process *process,
 371                                  struct thread *thread, int status )
 372 {
 373     if (process->debug_obj == debug_obj && thread->process == process)
 374     {
 375         struct debug_event *event;
 376
 377         if (status == DBG_REPLY_LATER)
 378         {
 379             /* if thread is suspended, delay all its events and resume process
 380              * if not, reset the event for immediate replay */
 381             LIST_FOR_EACH_ENTRY( event, &debug_obj->event_queue, struct debug_event, entry )
 382             {
 383                 if (event->sender != thread) continue;
 384                 if (thread->suspend)
 385                 {
 386                     delay_event( debug_obj, event );
 387                     resume_process( process );
 388                 }
 389                 else if (event->state == EVENT_SENT)
 390                 {
 391                     assert( event->sender->process->debug_event == event );
 392                     event->sender->process->debug_event = NULL;
 393                     resume_event( debug_obj, event );
 394                     return 1;
 395                 }
 396             }
 397             return 1;
 398         }
 399
 400         /* find the event in the queue */
 401         LIST_FOR_EACH_ENTRY( event, &debug_obj->event_queue, struct debug_event, entry )
 402         {
 403             if (event->state != EVENT_SENT) continue;
 404             if (event->sender == thread)
 405             {
 406                 assert( event->sender->process->debug_event == event );
 407                 event->status = status;
 408                 event->state  = EVENT_CONTINUED;
 409                 wake_up( &event->obj, 0 );
 410                 unlink_event( debug_obj, event );
 411                 resume_process( process );
 412                 return 1;
 413             }
 414         }
 415     }
 416     /* not debugging this process, or no such event */
 417     set_error( STATUS_ACCESS_DENIED );  /* FIXME */
 418     return 0;
 419 }
 420
 421 /* alloc a debug event for a debugger */
 422 static struct debug_event *alloc_debug_event( struct thread *thread, int code, const void *arg )
 423 {
 424     struct debug_event *event;
 425
 426     assert( code >= DbgCreateThreadStateChange && code <= DbgUnloadDllStateChange );
 427
 428     /* build the event */
 429     if (!(event = alloc_object( &debug_event_ops ))) return NULL;
 430     event->state     = EVENT_QUEUED;
 431     event->sender    = (struct thread *)grab_object( thread );
 432     event->file      = NULL;
 433     memset( &event->data, 0, sizeof(event->data) );
 434     fill_debug_event[code - DbgCreateThreadStateChange]( event, arg );
 435     event->data.code = code;
 436     return event;
 437 }
 438
 439 /* generate a debug event from inside the server and queue it */
 440 void generate_debug_event( struct thread *thread, int code, const void *arg )
 441 {
 442     struct debug_obj *debug_obj = thread->process->debug_obj;
 443
 444     if (debug_obj)
 445     {
 446         struct debug_event *event = alloc_debug_event( thread, code, arg );
 447         if (event)
 448         {
 449             link_event( debug_obj, event );
 450             suspend_process( thread->process );
 451             release_object( event );
 452         }
 453         clear_error();  /* ignore errors */
 454     }
 455 }
 456
 457 void resume_delayed_debug_events( struct thread *thread )
 458 {
 459     struct debug_obj *debug_obj = thread->process->debug_obj;
 460     struct debug_event *event;
 461
 462     if (debug_obj)
 463     {
 464         LIST_FOR_EACH_ENTRY( event, &debug_obj->event_queue, struct debug_event, entry )
 465         {
 466             if (event->sender != thread) continue;
 467             if (event->state != EVENT_DELAYED) continue;
 468             resume_event( debug_obj, event );
 469             suspend_process( thread->process );
 470         }
 471     }
 472 }
 473
 474 /* attach a process to a debugger thread and suspend it */
 475 static int debugger_attach( struct process *process, struct thread *debugger, struct debug_obj *debug_obj )
 476 {
 477     if (debugger->process == process) goto error;
 478     if (!is_process_init_done( process )) goto error;  /* still starting up */
 479     if (list_empty( &process->thread_list )) goto error;  /* no thread running in the process */
 480     /* don't let a debugger debug its console... won't work */
 481     if (debugger->process->console)
 482     {
 483         struct thread *renderer = console_get_renderer(debugger->process->console);
 484         if (renderer && renderer->process == process) goto error;
 485     }
 486
 487     suspend_process( process );
 488
 489     if (!set_process_debug_flag( process, 1 ))
 490     {
 491         resume_process( process );
 492         return 0;
 493     }
 494     process->debug_obj = debug_obj;
 495     process->debug_children = 0;
 496     generate_startup_debug_events( process );
 497     resume_process( process );
 498     return 1;
 499
 500  error:
 501     set_error( STATUS_ACCESS_DENIED );
 502     return 0;
 503 }
 504
 505
 506 /* detach a process from a debugger thread (and resume it) */
 507 void debugger_detach( struct process *process, struct debug_obj *debug_obj )
 508 {
 509     struct debug_event *event, *next;
 510
 511     suspend_process( process );
 512
 513     /* send continue indication for all events */
 514     LIST_FOR_EACH_ENTRY_SAFE( event, next, &debug_obj->event_queue, struct debug_event, entry )
 515     {
 516         if (event->sender->process != process) continue;
 517
 518         assert( event->state != EVENT_CONTINUED );
 519         event->status = DBG_CONTINUE;
 520         event->state  = EVENT_CONTINUED;
 521         wake_up( &event->obj, 0 );
 522         unlink_event( debug_obj, event );
 523         /* from queued debug event */
 524         resume_process( process );
 525     }
 526
 527     /* remove relationships between process and its debugger */
 528     process->debug_obj = NULL;
 529     if (!set_process_debug_flag( process, 0 )) clear_error();  /* ignore error */
 530
 531     resume_process( process );
 532 }
 533
 534 /* generate all startup events of a given process */
 535 void generate_startup_debug_events( struct process *process )
 536 {
 537     struct list *ptr;
 538     struct memory_view *view = get_exe_view( process );
 539     struct thread *thread, *first_thread = get_process_first_thread( process );
 540
 541     if (!view) return;
 542     generate_debug_event( first_thread, DbgCreateProcessStateChange, view );
 543     ptr = list_head( &process->dlls ); /* skip main module reported in create process event */
 544
 545     /* generate ntdll.dll load event */
 546     if (ptr && (ptr = list_next( &process->dlls, ptr )))
 547     {
 548         struct process_dll *dll = LIST_ENTRY( ptr, struct process_dll, entry );
 549         generate_debug_event( first_thread, DbgLoadDllStateChange, dll );
 550     }
 551
 552     /* generate creation events */
 553     LIST_FOR_EACH_ENTRY( thread, &process->thread_list, struct thread, proc_entry )
 554     {
 555         if (thread != first_thread)
 556             generate_debug_event( thread, DbgCreateThreadStateChange, NULL );
 557     }
 558
 559     /* generate dll events (in loading order) */
 560     while (ptr && (ptr = list_next( &process->dlls, ptr )))
 561     {
 562         struct process_dll *dll = LIST_ENTRY( ptr, struct process_dll, entry );
 563         generate_debug_event( first_thread, DbgLoadDllStateChange, dll );
 564     }
 565 }
 566
 567 /* create a debug object */
 568 DECL_HANDLER(create_debug_obj)
 569 {
 570     struct debug_obj *debug_obj;
 571     struct unicode_str name;
 572     struct object *root;
 573     const struct security_descriptor *sd;
 574     const struct object_attributes *objattr = get_req_object_attributes( &sd, &name, &root );
 575
 576     if (!objattr) return;
 577     if ((debug_obj = create_debug_obj( root, &name, objattr->attributes, req->flags, sd )))
 578     {
 579         if (get_error() == STATUS_OBJECT_NAME_EXISTS)
 580             reply->handle = alloc_handle( current->process, debug_obj, req->access, objattr->attributes );
 581         else
 582             reply->handle = alloc_handle_no_access_check( current->process, debug_obj,
 583                                                           req->access, objattr->attributes );
 584         release_object( debug_obj );
 585     }
 586     if (root) release_object( root );
 587 }
 588
 589 /* Wait for a debug event */
 590 DECL_HANDLER(wait_debug_event)
 591 {
 592     struct debug_obj *debug_obj;
 593     struct debug_event *event;
 594
 595     if (!(debug_obj = get_debug_obj( current->process, req->debug, DEBUG_READ_EVENT ))) return;
 596
 597     if ((event = find_event_to_send( debug_obj )))
 598     {
 599         event->state = EVENT_SENT;
 600         event->sender->process->debug_event = event;
 601         reply->pid = get_process_id( event->sender->process );
 602         reply->tid = get_thread_id( event->sender );
 603         alloc_event_handles( event, current->process );
 604         set_reply_data( &event->data, min( get_reply_max_size(), sizeof(event->data) ));
 605     }
 606     else
 607     {
 608         int state = list_empty( &debug_obj->event_queue ) ? DbgIdle : DbgReplyPending;
 609         set_reply_data( &state, min( get_reply_max_size(), sizeof(state) ));
 610     }
 611     release_object( debug_obj );
 612 }
 613
 614 /* Continue a debug event */
 615 DECL_HANDLER(continue_debug_event)
 616 {
 617     struct debug_obj *debug_obj;
 618     struct process *process;
 619
 620     if (req->status != DBG_EXCEPTION_NOT_HANDLED &&
 621         req->status != DBG_EXCEPTION_HANDLED &&
 622         req->status != DBG_CONTINUE &&
 623         req->status != DBG_REPLY_LATER)
 624     {
 625         set_error( STATUS_INVALID_PARAMETER );
 626         return;
 627     }
 628
 629     if (!(debug_obj = get_debug_obj( current->process, req->debug, DEBUG_READ_EVENT ))) return;
 630
 631     if ((process = get_process_from_id( req->pid )))
 632     {
 633         struct thread *thread = get_thread_from_id( req->tid );
 634         if (thread)
 635         {
 636             continue_debug_event( debug_obj, process, thread, req->status );
 637             release_object( thread );
 638         }
 639         release_object( process );
 640     }
 641     release_object( debug_obj );
 642 }
 643
 644 /* start or stop debugging an existing process */
 645 DECL_HANDLER(debug_process)
 646 {
 647     struct debug_obj *debug_obj;
 648     struct process *process = get_process_from_handle( req->handle,
 649                                             PROCESS_VM_READ | PROCESS_VM_WRITE | PROCESS_SUSPEND_RESUME );
 650
 651     if (!process) return;
 652     if ((debug_obj = get_debug_obj( current->process, req->debug, DEBUG_PROCESS_ASSIGN )))
 653     {
 654         if (req->attach)
 655         {
 656             if (!process->debug_obj) debugger_attach( process, current, debug_obj );
 657             else set_error( STATUS_ACCESS_DENIED );
 658         }
 659         else
 660         {
 661             if (process->debug_obj == debug_obj) debugger_detach( process, debug_obj );
 662             else set_error( STATUS_ACCESS_DENIED );
 663         }
 664         release_object( debug_obj );
 665     }
 666     release_object( process );
 667 }
 668
 669 /* queue an exception event */
 670 DECL_HANDLER(queue_exception_event)
 671 {
 672     struct debug_obj *debug_obj = current->process->debug_obj;
 673
 674     reply->handle = 0;
 675     if (debug_obj)
 676     {
 677         debug_event_t data;
 678         struct debug_event *event;
 679         struct thread *thread = current;
 680
 681         if ((req->len % sizeof(client_ptr_t)) != 0 ||
 682             req->len > get_req_data_size() ||
 683             req->len > EXCEPTION_MAXIMUM_PARAMETERS * sizeof(client_ptr_t))
 684         {
 685             set_error( STATUS_INVALID_PARAMETER );
 686             return;
 687         }
 688         memset( &data, 0, sizeof(data) );
 689         data.exception.first     = req->first;
 690         data.exception.exc_code  = req->code;
 691         data.exception.flags     = req->flags;
 692         data.exception.record    = req->record;
 693         data.exception.address   = req->address;
 694         data.exception.nb_params = req->len / sizeof(client_ptr_t);
 695         memcpy( data.exception.params, get_req_data(), req->len );
 696
 697         if ((event = alloc_debug_event( thread, DbgExceptionStateChange, &data )))
 698         {
 699             if ((reply->handle = alloc_handle( thread->process, event, SYNCHRONIZE, 0 )))
 700             {
 701                 link_event( debug_obj, event );
 702                 suspend_process( thread->process );
 703             }
 704             release_object( event );
 705         }
 706     }
 707 }
 708
 709 /* retrieve the status of an exception event */
 710 DECL_HANDLER(get_exception_status)
 711 {
 712     struct debug_event *event;
 713
 714     if ((event = (struct debug_event *)get_handle_obj( current->process, req->handle,
 715                                                        0, &debug_event_ops )))
 716     {
 717         close_handle( current->process, req->handle );
 718         set_error( event->state == EVENT_CONTINUED ? event->status : STATUS_PENDING );
 719         release_object( event );
 720     }
 721 }
 722
 723 /* set debug object information */
 724 DECL_HANDLER(set_debug_obj_info)
 725 {
 726     struct debug_obj *debug_obj;
 727
 728     if (!(debug_obj = get_debug_obj( current->process, req->debug, DEBUG_SET_INFORMATION ))) return;
 729     debug_obj->flags = req->flags;
 730     release_object( debug_obj );
 731 }