2 * Server-side thread management
4 * Copyright (C) 1998 Alexandre Julliard
14 #include <sys/types.h>
31 struct wait_queue_entry
33 struct wait_queue_entry *next;
34 struct wait_queue_entry *prev;
36 struct thread *thread;
41 int count; /* count of objects */
43 struct timeval timeout;
44 struct timeout_user *user;
45 struct wait_queue_entry queues[1];
48 /* asynchronous procedure calls */
52 void *func; /* function to call in client */
53 void *param; /* function param */
55 #define MAX_THREAD_APC 16 /* Max outstanding APCs for a thread */
58 /* thread operations */
60 static void dump_thread( struct object *obj, int verbose );
61 static int thread_signaled( struct object *obj, struct thread *thread );
62 static void destroy_thread( struct object *obj );
64 static const struct object_ops thread_ops =
66 sizeof(struct thread),
79 static struct thread *first_thread;
81 /* allocate the buffer for the communication with the client */
82 static int alloc_client_buffer( struct thread *thread )
86 if ((fd = create_anonymous_file()) == -1) return -1;
87 if (ftruncate( fd, MAX_REQUEST_LENGTH ) == -1) goto error;
88 if ((thread->buffer = mmap( 0, MAX_REQUEST_LENGTH, PROT_READ | PROT_WRITE,
89 MAP_SHARED, fd, 0 )) == (void*)-1) goto error;
94 if (fd != -1) close( fd );
98 /* create a new thread */
99 static struct thread *create_thread( int fd, struct process *process, int suspend )
101 struct thread *thread;
104 if (!(thread = alloc_object( &thread_ops ))) return NULL;
106 thread->client = NULL;
107 thread->unix_pid = 0; /* not known yet */
109 thread->mutex = NULL;
110 thread->debug_ctx = NULL;
111 thread->debug_first = NULL;
112 thread->debug_event = NULL;
115 thread->apc_count = 0;
117 thread->state = STARTING;
118 thread->exit_code = 0x103; /* STILL_ACTIVE */
121 thread->priority = THREAD_PRIORITY_NORMAL;
122 thread->affinity = 1;
123 thread->suspend = (suspend != 0);
124 thread->buffer = (void *)-1;
125 thread->last_req = REQ_GET_THREAD_BUFFER;
127 if (!first_thread) /* creating the first thread */
130 thread->process = process = create_initial_process();
133 else thread->process = (struct process *)grab_object( process );
135 if ((thread->next = first_thread) != NULL) thread->next->prev = thread;
136 first_thread = thread;
137 add_process_thread( process, thread );
139 if ((buf_fd = alloc_client_buffer( thread )) == -1) goto error;
140 if (!(thread->client = add_client( fd, thread )))
145 set_reply_fd( thread, buf_fd ); /* send the fd to the client */
146 send_reply( thread );
150 remove_process_thread( process, thread );
151 release_object( thread );
155 /* create the initial thread and start the main server loop */
156 void create_initial_thread( int fd )
158 create_thread( fd, NULL, 0 );
162 /* destroy a thread when its refcount is 0 */
163 static void destroy_thread( struct object *obj )
165 struct thread *thread = (struct thread *)obj;
166 assert( obj->ops == &thread_ops );
168 assert( !thread->debug_ctx ); /* cannot still be debugging something */
169 release_object( thread->process );
170 if (thread->next) thread->next->prev = thread->prev;
171 if (thread->prev) thread->prev->next = thread->next;
172 else first_thread = thread->next;
173 if (thread->apc) free( thread->apc );
174 if (thread->buffer != (void *)-1) munmap( thread->buffer, MAX_REQUEST_LENGTH );
177 /* dump a thread on stdout for debugging purposes */
178 static void dump_thread( struct object *obj, int verbose )
180 struct thread *thread = (struct thread *)obj;
181 assert( obj->ops == &thread_ops );
183 fprintf( stderr, "Thread pid=%d teb=%p state=%d\n",
184 thread->unix_pid, thread->teb, thread->state );
187 static int thread_signaled( struct object *obj, struct thread *thread )
189 struct thread *mythread = (struct thread *)obj;
190 return (mythread->state == TERMINATED);
193 /* get a thread pointer from a thread id (and increment the refcount) */
194 struct thread *get_thread_from_id( void *id )
196 struct thread *t = first_thread;
197 while (t && (t != id)) t = t->next;
198 if (t) grab_object( t );
202 /* get a thread from a handle (and increment the refcount) */
203 struct thread *get_thread_from_handle( int handle, unsigned int access )
205 return (struct thread *)get_handle_obj( current->process, handle,
206 access, &thread_ops );
209 /* set all information about a thread */
210 static void set_thread_info( struct thread *thread,
211 struct set_thread_info_request *req )
213 if (req->mask & SET_THREAD_INFO_PRIORITY)
214 thread->priority = req->priority;
215 if (req->mask & SET_THREAD_INFO_AFFINITY)
217 if (req->affinity != 1) set_error( ERROR_INVALID_PARAMETER );
218 else thread->affinity = req->affinity;
222 /* suspend a thread */
223 static int suspend_thread( struct thread *thread )
225 int old_count = thread->suspend;
226 if (thread->suspend < MAXIMUM_SUSPEND_COUNT)
228 if (!(thread->process->suspend + thread->suspend++))
230 if (thread->unix_pid) kill( thread->unix_pid, SIGSTOP );
236 /* resume a thread */
237 static int resume_thread( struct thread *thread )
239 int old_count = thread->suspend;
240 if (thread->suspend > 0)
242 if (!(--thread->suspend + thread->process->suspend))
244 if (thread->unix_pid) kill( thread->unix_pid, SIGCONT );
250 /* suspend all threads but the current */
251 void suspend_all_threads( void )
253 struct thread *thread;
254 for ( thread = first_thread; thread; thread = thread->next )
255 if ( thread != current )
256 suspend_thread( thread );
259 /* resume all threads but the current */
260 void resume_all_threads( void )
262 struct thread *thread;
263 for ( thread = first_thread; thread; thread = thread->next )
264 if ( thread != current )
265 resume_thread( thread );
268 /* add a thread to an object wait queue; return 1 if OK, 0 on error */
269 int add_queue( struct object *obj, struct wait_queue_entry *entry )
273 entry->prev = obj->tail;
275 if (obj->tail) obj->tail->next = entry;
276 else obj->head = entry;
281 /* remove a thread from an object wait queue */
282 void remove_queue( struct object *obj, struct wait_queue_entry *entry )
284 if (entry->next) entry->next->prev = entry->prev;
285 else obj->tail = entry->prev;
286 if (entry->prev) entry->prev->next = entry->next;
287 else obj->head = entry->next;
288 release_object( obj );
292 static void end_wait( struct thread *thread )
294 struct thread_wait *wait = thread->wait;
295 struct wait_queue_entry *entry;
299 for (i = 0, entry = wait->queues; i < wait->count; i++, entry++)
300 entry->obj->ops->remove_queue( entry->obj, entry );
301 if (wait->user) remove_timeout_user( wait->user );
306 /* build the thread wait structure */
307 static int wait_on( struct thread *thread, int count,
308 int *handles, int flags, int timeout )
310 struct thread_wait *wait;
311 struct wait_queue_entry *entry;
315 if ((count < 0) || (count > MAXIMUM_WAIT_OBJECTS))
317 set_error( ERROR_INVALID_PARAMETER );
320 if (!(wait = mem_alloc( sizeof(*wait) + (count-1) * sizeof(*entry) ))) return 0;
325 if (flags & SELECT_TIMEOUT) make_timeout( &wait->timeout, timeout );
327 for (i = 0, entry = wait->queues; i < count; i++, entry++)
329 if (!(obj = get_handle_obj( thread->process, handles[i],
330 SYNCHRONIZE, NULL )))
336 entry->thread = thread;
337 if (!obj->ops->add_queue( obj, entry ))
343 release_object( obj );
348 /* check if the thread waiting condition is satisfied */
349 static int check_wait( struct thread *thread, int *signaled )
352 struct thread_wait *wait = thread->wait;
353 struct wait_queue_entry *entry = wait->queues;
356 if (wait->flags & SELECT_ALL)
359 /* Note: we must check them all anyway, as some objects may
360 * want to do something when signaled, even if others are not */
361 for (i = 0, entry = wait->queues; i < wait->count; i++, entry++)
362 not_ok |= !entry->obj->ops->signaled( entry->obj, thread );
363 if (not_ok) goto other_checks;
364 /* Wait satisfied: tell it to all objects */
366 for (i = 0, entry = wait->queues; i < wait->count; i++, entry++)
367 if (entry->obj->ops->satisfied( entry->obj, thread ))
368 *signaled = STATUS_ABANDONED_WAIT_0;
373 for (i = 0, entry = wait->queues; i < wait->count; i++, entry++)
375 if (!entry->obj->ops->signaled( entry->obj, thread )) continue;
376 /* Wait satisfied: tell it to the object */
378 if (entry->obj->ops->satisfied( entry->obj, thread ))
379 *signaled = i + STATUS_ABANDONED_WAIT_0;
385 if ((wait->flags & SELECT_ALERTABLE) && thread->apc)
387 *signaled = STATUS_USER_APC;
390 if (wait->flags & SELECT_TIMEOUT)
393 gettimeofday( &now, NULL );
394 if ((now.tv_sec > wait->timeout.tv_sec) ||
395 ((now.tv_sec == wait->timeout.tv_sec) &&
396 (now.tv_usec >= wait->timeout.tv_usec)))
398 *signaled = STATUS_TIMEOUT;
405 /* attempt to wake up a thread */
406 /* return 1 if OK, 0 if the wait condition is still not satisfied */
407 static int wake_thread( struct thread *thread )
409 struct select_request *req = get_req_ptr( thread );
411 if (!check_wait( thread, &req->signaled )) return 0;
416 /* sleep on a list of objects */
417 static void sleep_on( struct thread *thread, int count, int *handles, int flags, int timeout )
419 struct select_request *req;
420 assert( !thread->wait );
421 if (!wait_on( thread, count, handles, flags, timeout )) goto error;
422 if (wake_thread( thread )) return;
423 /* now we need to wait */
424 if (flags & SELECT_TIMEOUT)
426 if (!(thread->wait->user = add_timeout_user( &thread->wait->timeout,
427 call_timeout_handler, thread )))
430 thread->state = SLEEPING;
434 req = get_req_ptr( thread );
438 /* timeout for the current thread */
439 void thread_timeout(void)
441 struct select_request *req = get_req_ptr( current );
443 assert( current->wait );
444 current->wait->user = NULL;
446 req->signaled = STATUS_TIMEOUT;
447 send_reply( current );
450 /* attempt to wake threads sleeping on the object wait queue */
451 void wake_up( struct object *obj, int max )
453 struct wait_queue_entry *entry = obj->head;
457 struct thread *thread = entry->thread;
459 if (wake_thread( thread ))
461 send_reply( thread );
462 if (max && !--max) break;
467 /* queue an async procedure call */
468 static int thread_queue_apc( struct thread *thread, void *func, void *param )
470 struct thread_apc *apc;
473 if (!(thread->apc = mem_alloc( MAX_THREAD_APC * sizeof(*apc) )))
475 thread->apc_count = 0;
477 else if (thread->apc_count >= MAX_THREAD_APC) return 0;
478 thread->apc[thread->apc_count].func = func;
479 thread->apc[thread->apc_count].param = param;
483 if (wake_thread( thread )) send_reply( thread );
488 /* kill a thread on the spot */
489 void kill_thread( struct thread *thread, int exit_code )
491 if (thread->state == TERMINATED) return; /* already killed */
492 if (thread->unix_pid) kill( thread->unix_pid, SIGTERM );
493 remove_client( thread->client, exit_code ); /* this will call thread_killed */
496 /* a thread has been killed */
497 void thread_killed( struct thread *thread, int exit_code )
499 thread->state = TERMINATED;
500 thread->exit_code = exit_code;
501 if (thread->wait) end_wait( thread );
502 debug_exit_thread( thread, exit_code );
503 abandon_mutexes( thread );
504 remove_process_thread( thread->process, thread );
505 wake_up( &thread->obj, 0 );
506 release_object( thread );
509 /* create a new thread */
510 DECL_HANDLER(new_thread)
512 struct thread *thread;
513 struct process *process;
515 if ((process = get_process_from_id( req->pid )))
517 if ((fd = dup(fd)) != -1)
519 if ((thread = create_thread( fd, process, req->suspend )))
522 if ((req->handle = alloc_handle( current->process, thread,
523 THREAD_ALL_ACCESS, req->inherit )) == -1)
524 release_object( thread );
525 /* else will be released when the thread gets killed */
529 else file_set_error();
530 release_object( process );
534 /* retrieve the thread buffer file descriptor */
535 DECL_HANDLER(get_thread_buffer)
537 fatal_protocol_error( current, "get_thread_buffer: should never get called directly\n" );
540 /* initialize a new thread */
541 DECL_HANDLER(init_thread)
543 if (current->state != STARTING)
545 fatal_protocol_error( current, "init_thread: already running\n" );
548 current->state = RUNNING;
549 current->unix_pid = req->unix_pid;
550 current->teb = req->teb;
551 if (current->suspend + current->process->suspend > 0)
552 kill( current->unix_pid, SIGSTOP );
553 req->pid = current->process;
557 /* terminate a thread */
558 DECL_HANDLER(terminate_thread)
560 struct thread *thread;
562 if ((thread = get_thread_from_handle( req->handle, THREAD_TERMINATE )))
564 kill_thread( thread, req->exit_code );
565 release_object( thread );
569 /* fetch information about a thread */
570 DECL_HANDLER(get_thread_info)
572 struct thread *thread;
574 if ((thread = get_thread_from_handle( req->handle, THREAD_QUERY_INFORMATION )))
577 req->exit_code = thread->exit_code;
578 req->priority = thread->priority;
579 release_object( thread );
583 /* set information about a thread */
584 DECL_HANDLER(set_thread_info)
586 struct thread *thread;
588 if ((thread = get_thread_from_handle( req->handle, THREAD_SET_INFORMATION )))
590 set_thread_info( thread, req );
591 release_object( thread );
595 /* suspend a thread */
596 DECL_HANDLER(suspend_thread)
598 struct thread *thread;
600 if ((thread = get_thread_from_handle( req->handle, THREAD_SUSPEND_RESUME )))
602 req->count = suspend_thread( thread );
603 release_object( thread );
607 /* resume a thread */
608 DECL_HANDLER(resume_thread)
610 struct thread *thread;
612 if ((thread = get_thread_from_handle( req->handle, THREAD_SUSPEND_RESUME )))
614 req->count = resume_thread( thread );
615 release_object( thread );
619 /* select on a handle list */
622 sleep_on( current, req->count, req->handles, req->flags, req->timeout );
625 /* queue an APC for a thread */
626 DECL_HANDLER(queue_apc)
628 struct thread *thread;
629 if ((thread = get_thread_from_handle( req->handle, THREAD_SET_CONTEXT )))
631 thread_queue_apc( thread, req->func, req->param );
632 release_object( thread );
636 /* get list of APC to call */
637 DECL_HANDLER(get_apcs)
639 if ((req->count = current->apc_count))
641 memcpy( req->apcs, current->apc, current->apc_count * sizeof(*current->apc) );
642 free( current->apc );
644 current->apc_count = 0;