server/thread.c

   1 /*
   2  * Server-side thread management
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  */
   6
   7 #include "config.h"
   8
   9 #include <assert.h>
  10 #include <fcntl.h>
  11 #include <signal.h>
  12 #include <stdarg.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #ifdef HAVE_SYS_MMAN_H
  17 #include <sys/mman.h>
  18 #endif
  19 #include <sys/types.h>
  20 #ifdef HAVE_SYS_SOCKET_H
  21 # include <sys/socket.h>
  22 #endif
  23 #include <sys/uio.h>
  24 #include <unistd.h>
  25 #include <stdarg.h>
  26
  27 #include "winbase.h"
  28
  29 #include "handle.h"
  30 #include "process.h"
  31 #include "thread.h"
  32 #include "request.h"
  33
  34
  35 /* thread queues */
  36
  37 struct thread_wait
  38 {
  39     int                     count;      /* count of objects */
  40     int                     flags;
  41     struct timeval          timeout;
  42     struct timeout_user    *user;
  43     sleep_reply             reply;      /* function to build the reply */
  44     struct wait_queue_entry queues[1];
  45 };
  46
  47 /* asynchronous procedure calls */
  48
  49 struct thread_apc
  50 {
  51     struct thread_apc  *next;     /* queue linked list */
  52     struct thread_apc  *prev;
  53     struct object      *owner;    /* object that queued this apc */
  54     void               *func;     /* function to call in client */
  55     enum apc_type       type;     /* type of apc function */
  56     int                 nb_args;  /* number of arguments */
  57     void               *args[1];  /* function arguments */
  58 };
  59
  60
  61 /* thread operations */
  62
  63 static void dump_thread( struct object *obj, int verbose );
  64 static int thread_signaled( struct object *obj, struct thread *thread );
  65 extern void thread_poll_event( struct object *obj, int event );
  66 static void destroy_thread( struct object *obj );
  67 static struct thread_apc *thread_dequeue_apc( struct thread *thread );
  68
  69 static const struct object_ops thread_ops =
  70 {
  71     sizeof(struct thread),      /* size */
  72     dump_thread,                /* dump */
  73     add_queue,                  /* add_queue */
  74     remove_queue,               /* remove_queue */
  75     thread_signaled,            /* signaled */
  76     no_satisfied,               /* satisfied */
  77     NULL,                       /* get_poll_events */
  78     thread_poll_event,          /* poll_event */
  79     no_get_fd,                  /* get_fd */
  80     no_flush,                   /* flush */
  81     no_get_file_info,           /* get_file_info */
  82     destroy_thread              /* destroy */
  83 };
  84
  85 static struct thread *first_thread;
  86 static struct thread *booting_thread;
  87
  88 /* allocate the buffer for the communication with the client */
  89 static int alloc_client_buffer( struct thread *thread )
  90 {
  91     struct get_thread_buffer_request *req;
  92     int fd, fd_pipe[2];
  93
  94     if (pipe( fd_pipe ) == -1)
  95     {
  96         file_set_error();
  97         return 0;
  98     }
  99     if ((fd = create_anonymous_file()) == -1) goto error;
 100     if (ftruncate( fd, MAX_REQUEST_LENGTH ) == -1) goto error;
 101     if ((thread->buffer = mmap( 0, MAX_REQUEST_LENGTH, PROT_READ | PROT_WRITE,
 102                                 MAP_SHARED, fd, 0 )) == (void*)-1) goto error;
 103     thread->buffer_info = (struct server_buffer_info *)((char *)thread->buffer + MAX_REQUEST_LENGTH) - 1;
 104     if (!(thread->request_fd = create_request_socket( thread ))) goto error;
 105     thread->reply_fd = fd_pipe[1];
 106     /* build the first request into the buffer and send it */
 107     req = thread->buffer;
 108     req->pid  = get_process_id( thread->process );
 109     req->tid  = get_thread_id( thread );
 110     req->boot = (thread == booting_thread);
 111     req->version = SERVER_PROTOCOL_VERSION;
 112
 113     /* add it here since send_client_fd may call kill_thread */
 114     add_process_thread( thread->process, thread );
 115
 116     send_client_fd( thread, fd_pipe[0], -1 );
 117     send_client_fd( thread, fd, -1 );
 118     send_reply( thread );
 119     close( fd_pipe[0] );
 120     close( fd );
 121     return 1;
 122
 123  error:
 124     file_set_error();
 125     if (fd != -1) close( fd );
 126     close( fd_pipe[0] );
 127     close( fd_pipe[1] );
 128     return 0;
 129 }
 130
 131 /* create a new thread */
 132 struct thread *create_thread( int fd, struct process *process )
 133 {
 134     struct thread *thread;
 135
 136     int flags = fcntl( fd, F_GETFL, 0 );
 137     fcntl( fd, F_SETFL, flags | O_NONBLOCK );
 138
 139     if (!(thread = alloc_object( &thread_ops, fd ))) return NULL;
 140
 141     thread->unix_pid    = 0;  /* not known yet */
 142     thread->context     = NULL;
 143     thread->teb         = NULL;
 144     thread->mutex       = NULL;
 145     thread->debug_ctx   = NULL;
 146     thread->debug_event = NULL;
 147     thread->queue       = NULL;
 148     thread->info        = NULL;
 149     thread->wait        = NULL;
 150     thread->apc_head    = NULL;
 151     thread->apc_tail    = NULL;
 152     thread->error       = 0;
 153     thread->pass_fd     = -1;
 154     thread->request_fd  = NULL;
 155     thread->reply_fd    = -1;
 156     thread->state       = RUNNING;
 157     thread->attached    = 0;
 158     thread->exit_code   = 0;
 159     thread->next        = NULL;
 160     thread->prev        = NULL;
 161     thread->priority    = THREAD_PRIORITY_NORMAL;
 162     thread->affinity    = 1;
 163     thread->suspend     = 0;
 164     thread->buffer      = (void *)-1;
 165     thread->last_req    = REQ_GET_THREAD_BUFFER;
 166     thread->process     = (struct process *)grab_object( process );
 167
 168     if (!current) current = thread;
 169
 170     if (!booting_thread)  /* first thread ever */
 171     {
 172         booting_thread = thread;
 173         lock_master_socket(1);
 174     }
 175
 176     if ((thread->next = first_thread) != NULL) thread->next->prev = thread;
 177     first_thread = thread;
 178
 179     set_select_events( &thread->obj, POLLIN );  /* start listening to events */
 180     if (!alloc_client_buffer( thread )) goto error;
 181     return thread;
 182
 183  error:
 184     release_object( thread );
 185     return NULL;
 186 }
 187
 188 /* handle a client event */
 189 void thread_poll_event( struct object *obj, int event )
 190 {
 191     struct thread *thread = (struct thread *)obj;
 192     assert( obj->ops == &thread_ops );
 193
 194     if (event & (POLLERR | POLLHUP)) kill_thread( thread, 0 );
 195     else
 196     {
 197         if (event & POLLOUT) write_request( thread );
 198         if (event & POLLIN) read_request( thread );
 199     }
 200 }
 201
 202 /* destroy a thread when its refcount is 0 */
 203 static void destroy_thread( struct object *obj )
 204 {
 205     struct thread_apc *apc;
 206     struct thread *thread = (struct thread *)obj;
 207     assert( obj->ops == &thread_ops );
 208
 209     assert( !thread->debug_ctx );  /* cannot still be debugging something */
 210     release_object( thread->process );
 211     if (thread->next) thread->next->prev = thread->prev;
 212     if (thread->prev) thread->prev->next = thread->next;
 213     else first_thread = thread->next;
 214     while ((apc = thread_dequeue_apc( thread ))) free( apc );
 215     if (thread->info) release_object( thread->info );
 216     if (thread->queue) release_object( thread->queue );
 217     if (thread->buffer != (void *)-1) munmap( thread->buffer, MAX_REQUEST_LENGTH );
 218     if (thread->reply_fd != -1) close( thread->reply_fd );
 219     if (thread->pass_fd != -1) close( thread->pass_fd );
 220     if (thread->request_fd) release_object( thread->request_fd );
 221 }
 222
 223 /* dump a thread on stdout for debugging purposes */
 224 static void dump_thread( struct object *obj, int verbose )
 225 {
 226     struct thread *thread = (struct thread *)obj;
 227     assert( obj->ops == &thread_ops );
 228
 229     fprintf( stderr, "Thread pid=%d teb=%p state=%d\n",
 230              thread->unix_pid, thread->teb, thread->state );
 231 }
 232
 233 static int thread_signaled( struct object *obj, struct thread *thread )
 234 {
 235     struct thread *mythread = (struct thread *)obj;
 236     return (mythread->state == TERMINATED);
 237 }
 238
 239 /* get a thread pointer from a thread id (and increment the refcount) */
 240 struct thread *get_thread_from_id( void *id )
 241 {
 242     struct thread *t = first_thread;
 243     while (t && (t != id)) t = t->next;
 244     if (t) grab_object( t );
 245     return t;
 246 }
 247
 248 /* get a thread from a handle (and increment the refcount) */
 249 struct thread *get_thread_from_handle( int handle, unsigned int access )
 250 {
 251     return (struct thread *)get_handle_obj( current->process, handle,
 252                                             access, &thread_ops );
 253 }
 254
 255 /* find a thread from a Unix pid */
 256 struct thread *get_thread_from_pid( int pid )
 257 {
 258     struct thread *t = first_thread;
 259     while (t && (t->unix_pid != pid)) t = t->next;
 260     return t;
 261 }
 262
 263 /* set all information about a thread */
 264 static void set_thread_info( struct thread *thread,
 265                              struct set_thread_info_request *req )
 266 {
 267     if (req->mask & SET_THREAD_INFO_PRIORITY)
 268         thread->priority = req->priority;
 269     if (req->mask & SET_THREAD_INFO_AFFINITY)
 270     {
 271         if (req->affinity != 1) set_error( STATUS_INVALID_PARAMETER );
 272         else thread->affinity = req->affinity;
 273     }
 274 }
 275
 276 /* suspend a thread */
 277 int suspend_thread( struct thread *thread, int check_limit )
 278 {
 279     int old_count = thread->suspend;
 280     if (thread->suspend < MAXIMUM_SUSPEND_COUNT || !check_limit)
 281     {
 282         if (!(thread->process->suspend + thread->suspend++)) stop_thread( thread );
 283     }
 284     else set_error( STATUS_SUSPEND_COUNT_EXCEEDED );
 285     return old_count;
 286 }
 287
 288 /* resume a thread */
 289 int resume_thread( struct thread *thread )
 290 {
 291     int old_count = thread->suspend;
 292     if (thread->suspend > 0)
 293     {
 294         if (!(--thread->suspend + thread->process->suspend)) continue_thread( thread );
 295     }
 296     return old_count;
 297 }
 298
 299 /* suspend all threads but the current */
 300 void suspend_all_threads( void )
 301 {
 302     struct thread *thread;
 303     for ( thread = first_thread; thread; thread = thread->next )
 304         if ( thread != current )
 305             suspend_thread( thread, 0 );
 306 }
 307
 308 /* resume all threads but the current */
 309 void resume_all_threads( void )
 310 {
 311     struct thread *thread;
 312     for ( thread = first_thread; thread; thread = thread->next )
 313         if ( thread != current )
 314             resume_thread( thread );
 315 }
 316
 317 /* add a thread to an object wait queue; return 1 if OK, 0 on error */
 318 int add_queue( struct object *obj, struct wait_queue_entry *entry )
 319 {
 320     grab_object( obj );
 321     entry->obj    = obj;
 322     entry->prev   = obj->tail;
 323     entry->next   = NULL;
 324     if (obj->tail) obj->tail->next = entry;
 325     else obj->head = entry;
 326     obj->tail = entry;
 327     return 1;
 328 }
 329
 330 /* remove a thread from an object wait queue */
 331 void remove_queue( struct object *obj, struct wait_queue_entry *entry )
 332 {
 333     if (entry->next) entry->next->prev = entry->prev;
 334     else obj->tail = entry->prev;
 335     if (entry->prev) entry->prev->next = entry->next;
 336     else obj->head = entry->next;
 337     release_object( obj );
 338 }
 339
 340 /* finish waiting */
 341 static void end_wait( struct thread *thread )
 342 {
 343     struct thread_wait *wait = thread->wait;
 344     struct wait_queue_entry *entry;
 345     int i;
 346
 347     assert( wait );
 348     for (i = 0, entry = wait->queues; i < wait->count; i++, entry++)
 349         entry->obj->ops->remove_queue( entry->obj, entry );
 350     if (wait->user) remove_timeout_user( wait->user );
 351     free( wait );
 352     thread->wait = NULL;
 353 }
 354
 355 /* build the thread wait structure */
 356 static int wait_on( int count, struct object *objects[], int flags,
 357                     int timeout, sleep_reply func )
 358 {
 359     struct thread_wait *wait;
 360     struct wait_queue_entry *entry;
 361     int i;
 362
 363     if (!(wait = mem_alloc( sizeof(*wait) + (count-1) * sizeof(*entry) ))) return 0;
 364     current->wait = wait;
 365     wait->count   = count;
 366     wait->flags   = flags;
 367     wait->user    = NULL;
 368     wait->reply   = func;
 369     if (flags & SELECT_TIMEOUT)
 370     {
 371         gettimeofday( &wait->timeout, 0 );
 372         add_timeout( &wait->timeout, timeout );
 373     }
 374
 375     for (i = 0, entry = wait->queues; i < count; i++, entry++)
 376     {
 377         struct object *obj = objects[i];
 378         entry->thread = current;
 379         if (!obj->ops->add_queue( obj, entry ))
 380         {
 381             wait->count = i;
 382             end_wait( current );
 383             return 0;
 384         }
 385     }
 386     return 1;
 387 }
 388
 389 /* check if the thread waiting condition is satisfied */
 390 static int check_wait( struct thread *thread, struct object **object )
 391 {
 392     int i, signaled;
 393     struct thread_wait *wait = thread->wait;
 394     struct wait_queue_entry *entry = wait->queues;
 395
 396     assert( wait );
 397     *object = NULL;
 398     if (wait->flags & SELECT_ALL)
 399     {
 400         int not_ok = 0;
 401         /* Note: we must check them all anyway, as some objects may
 402          * want to do something when signaled, even if others are not */
 403         for (i = 0, entry = wait->queues; i < wait->count; i++, entry++)
 404             not_ok |= !entry->obj->ops->signaled( entry->obj, thread );
 405         if (not_ok) goto other_checks;
 406         /* Wait satisfied: tell it to all objects */
 407         signaled = 0;
 408         for (i = 0, entry = wait->queues; i < wait->count; i++, entry++)
 409             if (entry->obj->ops->satisfied( entry->obj, thread ))
 410                 signaled = STATUS_ABANDONED_WAIT_0;
 411         return signaled;
 412     }
 413     else
 414     {
 415         for (i = 0, entry = wait->queues; i < wait->count; i++, entry++)
 416         {
 417             if (!entry->obj->ops->signaled( entry->obj, thread )) continue;
 418             /* Wait satisfied: tell it to the object */
 419             signaled = i;
 420             *object = entry->obj;
 421             if (entry->obj->ops->satisfied( entry->obj, thread ))
 422                 signaled = i + STATUS_ABANDONED_WAIT_0;
 423             return signaled;
 424         }
 425     }
 426
 427  other_checks:
 428     if ((wait->flags & SELECT_ALERTABLE) && thread->apc_head) return STATUS_USER_APC;
 429     if (wait->flags & SELECT_TIMEOUT)
 430     {
 431         struct timeval now;
 432         gettimeofday( &now, NULL );
 433         if (!time_before( &now, &wait->timeout )) return STATUS_TIMEOUT;
 434     }
 435     return -1;
 436 }
 437
 438 /* build a reply to the select request */
 439 static void build_select_reply( struct thread *thread, struct object *obj, int signaled )
 440 {
 441     struct select_request *req = get_req_ptr( thread );
 442     req->signaled = signaled;
 443 }
 444
 445 /* attempt to wake up a thread */
 446 /* return 1 if OK, 0 if the wait condition is still not satisfied */
 447 static int wake_thread( struct thread *thread )
 448 {
 449     int signaled;
 450     struct object *object;
 451     if ((signaled = check_wait( thread, &object )) == -1) return 0;
 452     thread->error = 0;
 453     thread->wait->reply( thread, object, signaled );
 454     end_wait( thread );
 455     return 1;
 456 }
 457
 458 /* thread wait timeout */
 459 static void thread_timeout( void *ptr )
 460 {
 461     struct thread *thread = ptr;
 462     if (debug_level) fprintf( stderr, "%08x: *timeout*\n", (unsigned int)thread );
 463     assert( thread->wait );
 464     thread->error = 0;
 465     thread->wait->user = NULL;
 466     thread->wait->reply( thread, NULL, STATUS_TIMEOUT );
 467     end_wait( thread );
 468     send_reply( thread );
 469 }
 470
 471 /* sleep on a list of objects */
 472 int sleep_on( int count, struct object *objects[], int flags, int timeout, sleep_reply func )
 473 {
 474     assert( !current->wait );
 475     if (!wait_on( count, objects, flags, timeout, func )) return 0;
 476     if (wake_thread( current )) return 1;
 477     /* now we need to wait */
 478     if (flags & SELECT_TIMEOUT)
 479     {
 480         if (!(current->wait->user = add_timeout_user( &current->wait->timeout,
 481                                                       thread_timeout, current )))
 482         {
 483             end_wait( current );
 484             return 0;
 485         }
 486     }
 487     return 1;
 488 }
 489
 490 /* select on a list of handles */
 491 static int select_on( int count, int *handles, int flags, int timeout )
 492 {
 493     int ret = 0;
 494     int i;
 495     struct object *objects[MAXIMUM_WAIT_OBJECTS];
 496
 497     if ((count < 0) || (count > MAXIMUM_WAIT_OBJECTS))
 498     {
 499         set_error( STATUS_INVALID_PARAMETER );
 500         return 0;
 501     }
 502     for (i = 0; i < count; i++)
 503     {
 504         if (!(objects[i] = get_handle_obj( current->process, handles[i], SYNCHRONIZE, NULL )))
 505             break;
 506     }
 507     if (i == count) ret = sleep_on( count, objects, flags, timeout, build_select_reply );
 508     while (--i >= 0) release_object( objects[i] );
 509     return ret;
 510 }
 511
 512 /* attempt to wake threads sleeping on the object wait queue */
 513 void wake_up( struct object *obj, int max )
 514 {
 515     struct wait_queue_entry *entry = obj->head;
 516
 517     while (entry)
 518     {
 519         struct thread *thread = entry->thread;
 520         entry = entry->next;
 521         if (wake_thread( thread ))
 522         {
 523             send_reply( thread );
 524             if (max && !--max) break;
 525         }
 526     }
 527 }
 528
 529 /* queue an async procedure call */
 530 int thread_queue_apc( struct thread *thread, struct object *owner, void *func,
 531                       enum apc_type type, int nb_args, ... )
 532 {
 533     struct thread_apc *apc;
 534
 535     /* cancel a possible previous APC with the same owner */
 536     if (owner) thread_cancel_apc( thread, owner );
 537
 538     if (!(apc = mem_alloc( sizeof(*apc) + (nb_args-1)*sizeof(apc->args[0]) ))) return 0;
 539     apc->prev    = thread->apc_tail;
 540     apc->next    = NULL;
 541     apc->owner   = owner;
 542     apc->func    = func;
 543     apc->type    = type;
 544     apc->nb_args = nb_args;
 545     if (nb_args)
 546     {
 547         int i;
 548         va_list args;
 549         va_start( args, nb_args );
 550         for (i = 0; i < nb_args; i++) apc->args[i] = va_arg( args, void * );
 551         va_end( args );
 552     }
 553     thread->apc_tail = apc;
 554     if (!apc->prev)  /* first one */
 555     {
 556         thread->apc_head = apc;
 557         if (thread->wait && wake_thread( thread )) send_reply( thread );
 558     }
 559     return 1;
 560 }
 561
 562 /* cancel the async procedure call owned by a specific object */
 563 void thread_cancel_apc( struct thread *thread, struct object *owner )
 564 {
 565     struct thread_apc *apc;
 566     for (apc = thread->apc_head; apc; apc = apc->next)
 567     {
 568         if (apc->owner != owner) continue;
 569         if (apc->next) apc->next->prev = apc->prev;
 570         else thread->apc_tail = apc->prev;
 571         if (apc->prev) apc->prev->next = apc->next;
 572         else thread->apc_head = apc->next;
 573         free( apc );
 574         return;
 575     }
 576 }
 577
 578 /* remove the head apc from the queue; the returned pointer must be freed by the caller */
 579 static struct thread_apc *thread_dequeue_apc( struct thread *thread )
 580 {
 581     struct thread_apc *apc = thread->apc_head;
 582     if (apc)
 583     {
 584         if (apc->next) apc->next->prev = NULL;
 585         else thread->apc_tail = NULL;
 586         thread->apc_head = apc->next;
 587     }
 588     return apc;
 589 }
 590
 591 /* retrieve an LDT selector entry */
 592 static void get_selector_entry( struct thread *thread, int entry,
 593                                 unsigned int *base, unsigned int *limit,
 594                                 unsigned char *flags )
 595 {
 596     if (!thread->process->ldt_copy)
 597     {
 598         set_error( STATUS_ACCESS_DENIED );
 599         return;
 600     }
 601     if (entry >= 8192)
 602     {
 603         set_error( STATUS_INVALID_PARAMETER );  /* FIXME */
 604         return;
 605     }
 606     if (suspend_for_ptrace( thread ))
 607     {
 608         unsigned char flags_buf[4];
 609         int *addr = (int *)thread->process->ldt_copy + entry;
 610         if (read_thread_int( thread, addr, base ) == -1) goto done;
 611         if (read_thread_int( thread, addr + 8192, limit ) == -1) goto done;
 612         addr = (int *)thread->process->ldt_copy + 2*8192 + (entry >> 2);
 613         if (read_thread_int( thread, addr, (int *)flags_buf ) == -1) goto done;
 614         *flags = flags_buf[entry & 3];
 615     done:
 616         resume_thread( thread );
 617     }
 618 }
 619
 620 /* kill a thread on the spot */
 621 void kill_thread( struct thread *thread, int violent_death )
 622 {
 623     if (thread->state == TERMINATED) return;  /* already killed */
 624     thread->state = TERMINATED;
 625     if (current == thread) current = NULL;
 626     if (debug_level)
 627         fprintf( stderr,"%08x: *killed* exit_code=%d\n",
 628                  (unsigned int)thread, thread->exit_code );
 629     if (thread->wait)
 630     {
 631         end_wait( thread );
 632         /* if it is waiting on the socket, we don't need to send a SIGTERM */
 633         violent_death = 0;
 634     }
 635     debug_exit_thread( thread );
 636     abandon_mutexes( thread );
 637     remove_process_thread( thread->process, thread );
 638     wake_up( &thread->obj, 0 );
 639     detach_thread( thread, violent_death ? SIGTERM : 0 );
 640     remove_select_user( &thread->obj );
 641     release_object( thread->request_fd );
 642     close( thread->reply_fd );
 643     munmap( thread->buffer, MAX_REQUEST_LENGTH );
 644     thread->request_fd = NULL;
 645     thread->reply_fd = -1;
 646     thread->buffer = (void *)-1;
 647     release_object( thread );
 648 }
 649
 650 /* take a snapshot of currently running threads */
 651 struct thread_snapshot *thread_snap( int *count )
 652 {
 653     struct thread_snapshot *snapshot, *ptr;
 654     struct thread *thread;
 655     int total = 0;
 656
 657     for (thread = first_thread; thread; thread = thread->next)
 658         if (thread->state != TERMINATED) total++;
 659     if (!total || !(snapshot = mem_alloc( sizeof(*snapshot) * total ))) return NULL;
 660     ptr = snapshot;
 661     for (thread = first_thread; thread; thread = thread->next)
 662     {
 663         if (thread->state == TERMINATED) continue;
 664         ptr->thread   = thread;
 665         ptr->count    = thread->obj.refcount;
 666         ptr->priority = thread->priority;
 667         grab_object( thread );
 668         ptr++;
 669     }
 670     *count = total;
 671     return snapshot;
 672 }
 673
 674 /* signal that we are finished booting on the client side */
 675 DECL_HANDLER(boot_done)
 676 {
 677     debug_level = max( debug_level, req->debug_level );
 678     /* Make sure last_req is initialized */
 679     current->last_req = REQ_BOOT_DONE;
 680     if (current == booting_thread)
 681     {
 682         booting_thread = (struct thread *)~0UL;  /* make sure it doesn't match other threads */
 683         lock_master_socket(0);  /* allow other clients now */
 684     }
 685 }
 686
 687 /* create a new thread */
 688 DECL_HANDLER(new_thread)
 689 {
 690     struct thread *thread;
 691     int sock[2];
 692
 693     if (socketpair( AF_UNIX, SOCK_STREAM, 0, sock ) != -1)
 694     {
 695         if ((thread = create_thread( sock[0], current->process )))
 696         {
 697             if (req->suspend) thread->suspend++;
 698             req->tid = thread;
 699             if ((req->handle = alloc_handle( current->process, thread,
 700                                              THREAD_ALL_ACCESS, req->inherit )) != -1)
 701             {
 702                 send_client_fd( current, sock[1], req->handle );
 703                 close( sock[1] );
 704                 /* thread object will be released when the thread gets killed */
 705                 return;
 706             }
 707             kill_thread( thread, 1 );
 708         }
 709         close( sock[1] );
 710     }
 711     else file_set_error();
 712 }
 713
 714 /* retrieve the thread buffer file descriptor */
 715 DECL_HANDLER(get_thread_buffer)
 716 {
 717     fatal_protocol_error( current, "get_thread_buffer: should never get called directly\n" );
 718 }
 719
 720 /* initialize a new thread */
 721 DECL_HANDLER(init_thread)
 722 {
 723     if (current->unix_pid)
 724     {
 725         fatal_protocol_error( current, "init_thread: already running\n" );
 726         return;
 727     }
 728     current->unix_pid = req->unix_pid;
 729     current->teb      = req->teb;
 730     if (current->suspend + current->process->suspend > 0) stop_thread( current );
 731     if (current->process->running_threads > 1)
 732         generate_debug_event( current, CREATE_THREAD_DEBUG_EVENT, req->entry );
 733 }
 734
 735 /* terminate a thread */
 736 DECL_HANDLER(terminate_thread)
 737 {
 738     struct thread *thread;
 739
 740     req->self = 0;
 741     req->last = 0;
 742     if ((thread = get_thread_from_handle( req->handle, THREAD_TERMINATE )))
 743     {
 744         thread->exit_code = req->exit_code;
 745         if (thread != current) kill_thread( thread, 1 );
 746         else
 747         {
 748             req->self = 1;
 749             req->last = (thread->process->running_threads == 1);
 750         }
 751         release_object( thread );
 752     }
 753 }
 754
 755 /* fetch information about a thread */
 756 DECL_HANDLER(get_thread_info)
 757 {
 758     struct thread *thread;
 759     int handle = req->handle;
 760
 761     if (handle == -1) thread = get_thread_from_id( req->tid_in );
 762     else thread = get_thread_from_handle( req->handle, THREAD_QUERY_INFORMATION );
 763
 764     if (thread)
 765     {
 766         req->tid       = get_thread_id( thread );
 767         req->teb       = thread->teb;
 768         req->exit_code = (thread->state == TERMINATED) ? thread->exit_code : STILL_ACTIVE;
 769         req->priority  = thread->priority;
 770         release_object( thread );
 771     }
 772 }
 773
 774 /* set information about a thread */
 775 DECL_HANDLER(set_thread_info)
 776 {
 777     struct thread *thread;
 778
 779     if ((thread = get_thread_from_handle( req->handle, THREAD_SET_INFORMATION )))
 780     {
 781         set_thread_info( thread, req );
 782         release_object( thread );
 783     }
 784 }
 785
 786 /* suspend a thread */
 787 DECL_HANDLER(suspend_thread)
 788 {
 789     struct thread *thread;
 790
 791     if ((thread = get_thread_from_handle( req->handle, THREAD_SUSPEND_RESUME )))
 792     {
 793         req->count = suspend_thread( thread, 1 );
 794         release_object( thread );
 795     }
 796 }
 797
 798 /* resume a thread */
 799 DECL_HANDLER(resume_thread)
 800 {
 801     struct thread *thread;
 802
 803     if ((thread = get_thread_from_handle( req->handle, THREAD_SUSPEND_RESUME )))
 804     {
 805         req->count = resume_thread( thread );
 806         release_object( thread );
 807     }
 808 }
 809
 810 /* select on a handle list */
 811 DECL_HANDLER(select)
 812 {
 813     int count = get_req_data_size(req) / sizeof(int);
 814     if (!select_on( count, get_req_data(req), req->flags, req->timeout ))
 815         req->signaled = -1;
 816 }
 817
 818 /* queue an APC for a thread */
 819 DECL_HANDLER(queue_apc)
 820 {
 821     struct thread *thread;
 822     if ((thread = get_thread_from_handle( req->handle, THREAD_SET_CONTEXT )))
 823     {
 824         thread_queue_apc( thread, NULL, req->func, APC_USER, 1, req->param );
 825         release_object( thread );
 826     }
 827 }
 828
 829 /* get next APC to call */
 830 DECL_HANDLER(get_apc)
 831 {
 832     struct thread_apc *apc;
 833     size_t size;
 834
 835     for (;;)
 836     {
 837         if (!(apc = thread_dequeue_apc( current )))
 838         {
 839             /* no more APCs */
 840             req->func    = NULL;
 841             req->type    = APC_NONE;
 842             set_req_data_size( req, 0 );
 843             return;
 844         }
 845         /* Optimization: ignore APCs that have a NULL func; they are only used
 846          * to wake up a thread, but since we got here the thread woke up already.
 847          */
 848         if (apc->func) break;
 849         free( apc );
 850     }
 851     size = apc->nb_args * sizeof(apc->args[0]);
 852     if (size > get_req_data_size(req)) size = get_req_data_size(req);
 853     req->func = apc->func;
 854     req->type = apc->type;
 855     memcpy( get_req_data(req), apc->args, size );
 856     set_req_data_size( req, size );
 857     free( apc );
 858 }
 859
 860 /* fetch a selector entry for a thread */
 861 DECL_HANDLER(get_selector_entry)
 862 {
 863     struct thread *thread;
 864     if ((thread = get_thread_from_handle( req->handle, THREAD_QUERY_INFORMATION )))
 865     {
 866         get_selector_entry( thread, req->entry, &req->base, &req->limit, &req->flags );
 867         release_object( thread );
 868     }
 869 }