/* * Server-side thread management * * Copyright (C) 1998 Alexandre Julliard * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include "config.h" #include #include #include #include #include #include #include #include #include #include #include #include "winbase.h" #include "handle.h" #include "process.h" #include "thread.h" #include "request.h" #include "user.h" /* thread queues */ struct thread_wait { struct thread_wait *next; /* next wait structure for this thread */ struct thread *thread; /* owner thread */ int count; /* count of objects */ int flags; void *cookie; /* magic cookie to return to client */ struct timeval timeout; struct timeout_user *user; struct wait_queue_entry queues[1]; }; /* asynchronous procedure calls */ struct thread_apc { struct thread_apc *next; /* queue linked list */ struct thread_apc *prev; struct object *owner; /* object that queued this apc */ void *func; /* function to call in client */ enum apc_type type; /* type of apc function */ int nb_args; /* number of arguments */ void *args[1]; /* function arguments */ }; /* thread operations */ static void dump_thread( struct object *obj, int verbose ); static int thread_signaled( struct object *obj, struct thread *thread ); static void thread_poll_event( struct object *obj, int event ); static void destroy_thread( struct object *obj ); static struct thread_apc *thread_dequeue_apc( struct thread *thread, int system_only ); static const struct object_ops thread_ops = { sizeof(struct thread), /* size */ dump_thread, /* dump */ add_queue, /* add_queue */ remove_queue, /* remove_queue */ thread_signaled, /* signaled */ no_satisfied, /* satisfied */ NULL, /* get_poll_events */ thread_poll_event, /* poll_event */ no_get_fd, /* get_fd */ no_flush, /* flush */ no_get_file_info, /* get_file_info */ NULL, /* queue_async */ destroy_thread /* destroy */ }; static struct thread *first_thread; static struct thread *booting_thread; /* initialize the structure for a newly allocated thread */ inline static void init_thread_structure( struct thread *thread ) { int i; thread->unix_pid = 0; /* not known yet */ thread->context = NULL; thread->teb = NULL; thread->mutex = NULL; thread->debug_ctx = NULL; thread->debug_event = NULL; thread->queue = NULL; thread->info = NULL; thread->wait = NULL; thread->system_apc.head = NULL; thread->system_apc.tail = NULL; thread->user_apc.head = NULL; thread->user_apc.tail = NULL; thread->error = 0; thread->req_data = NULL; thread->req_toread = 0; thread->reply_data = NULL; thread->reply_towrite = 0; thread->reply_fd = -1; thread->wait_fd = -1; thread->state = RUNNING; thread->attached = 0; thread->exit_code = 0; thread->next = NULL; thread->prev = NULL; thread->priority = THREAD_PRIORITY_NORMAL; thread->affinity = 1; thread->suspend = 0; for (i = 0; i < MAX_INFLIGHT_FDS; i++) thread->inflight[i].server = thread->inflight[i].client = -1; } /* create a new thread */ struct thread *create_thread( int fd, struct process *process ) { struct thread *thread; if (!(thread = alloc_object( &thread_ops, fd ))) return NULL; init_thread_structure( thread ); thread->process = (struct process *)grab_object( process ); thread->request_fd = fd; if (!current) current = thread; if (!booting_thread) /* first thread ever */ { booting_thread = thread; lock_master_socket(1); } if ((thread->next = first_thread) != NULL) thread->next->prev = thread; first_thread = thread; set_select_events( &thread->obj, POLLIN ); /* start listening to events */ add_process_thread( thread->process, thread ); return thread; } /* handle a client event */ static void thread_poll_event( struct object *obj, int event ) { struct thread *thread = (struct thread *)obj; assert( obj->ops == &thread_ops ); if (event & (POLLERR | POLLHUP)) kill_thread( thread, 0 ); else if (event & POLLIN) read_request( thread ); else if (event & POLLOUT) write_reply( thread ); } /* cleanup everything that is no longer needed by a dead thread */ /* used by destroy_thread and kill_thread */ static void cleanup_thread( struct thread *thread ) { int i; struct thread_apc *apc; while ((apc = thread_dequeue_apc( thread, 0 ))) free( apc ); if (thread->req_data) free( thread->req_data ); if (thread->reply_data) free( thread->reply_data ); if (thread->request_fd != -1) close( thread->request_fd ); if (thread->reply_fd != -1) close( thread->reply_fd ); if (thread->wait_fd != -1) close( thread->wait_fd ); if (thread->queue) { if (thread->process->queue == thread->queue) { release_object( thread->process->queue ); thread->process->queue = NULL; } release_object( thread->queue ); thread->queue = NULL; } destroy_thread_windows( thread ); for (i = 0; i < MAX_INFLIGHT_FDS; i++) { if (thread->inflight[i].client != -1) { close( thread->inflight[i].server ); thread->inflight[i].client = thread->inflight[i].server = -1; } } thread->req_data = NULL; thread->reply_data = NULL; thread->request_fd = -1; thread->reply_fd = -1; thread->wait_fd = -1; } /* destroy a thread when its refcount is 0 */ static void destroy_thread( struct object *obj ) { struct thread_apc *apc; struct thread *thread = (struct thread *)obj; assert( obj->ops == &thread_ops ); assert( !thread->debug_ctx ); /* cannot still be debugging something */ if (thread->next) thread->next->prev = thread->prev; if (thread->prev) thread->prev->next = thread->next; else first_thread = thread->next; while ((apc = thread_dequeue_apc( thread, 0 ))) free( apc ); if (thread->info) release_object( thread->info ); cleanup_thread( thread ); release_object( thread->process ); } /* dump a thread on stdout for debugging purposes */ static void dump_thread( struct object *obj, int verbose ) { struct thread *thread = (struct thread *)obj; assert( obj->ops == &thread_ops ); fprintf( stderr, "Thread pid=%d teb=%p state=%d\n", thread->unix_pid, thread->teb, thread->state ); } static int thread_signaled( struct object *obj, struct thread *thread ) { struct thread *mythread = (struct thread *)obj; return (mythread->state == TERMINATED); } /* get a thread pointer from a thread id (and increment the refcount) */ struct thread *get_thread_from_id( void *id ) { struct thread *t = first_thread; while (t && (t != id)) t = t->next; if (t) grab_object( t ); else set_error( STATUS_INVALID_PARAMETER ); return t; } /* get a thread from a handle (and increment the refcount) */ struct thread *get_thread_from_handle( handle_t handle, unsigned int access ) { return (struct thread *)get_handle_obj( current->process, handle, access, &thread_ops ); } /* find a thread from a Unix pid */ struct thread *get_thread_from_pid( int pid ) { struct thread *t = first_thread; while (t && (t->unix_pid != pid)) t = t->next; return t; } /* set all information about a thread */ static void set_thread_info( struct thread *thread, const struct set_thread_info_request *req ) { if (req->mask & SET_THREAD_INFO_PRIORITY) thread->priority = req->priority; if (req->mask & SET_THREAD_INFO_AFFINITY) { if (req->affinity != 1) set_error( STATUS_INVALID_PARAMETER ); else thread->affinity = req->affinity; } } /* suspend a thread */ int suspend_thread( struct thread *thread, int check_limit ) { int old_count = thread->suspend; if (thread->suspend < MAXIMUM_SUSPEND_COUNT || !check_limit) { if (!(thread->process->suspend + thread->suspend++)) stop_thread( thread ); } else set_error( STATUS_SUSPEND_COUNT_EXCEEDED ); return old_count; } /* resume a thread */ int resume_thread( struct thread *thread ) { int old_count = thread->suspend; if (thread->suspend > 0) { if (!(--thread->suspend + thread->process->suspend)) continue_thread( thread ); } return old_count; } /* add a thread to an object wait queue; return 1 if OK, 0 on error */ int add_queue( struct object *obj, struct wait_queue_entry *entry ) { grab_object( obj ); entry->obj = obj; entry->prev = obj->tail; entry->next = NULL; if (obj->tail) obj->tail->next = entry; else obj->head = entry; obj->tail = entry; return 1; } /* remove a thread from an object wait queue */ void remove_queue( struct object *obj, struct wait_queue_entry *entry ) { if (entry->next) entry->next->prev = entry->prev; else obj->tail = entry->prev; if (entry->prev) entry->prev->next = entry->next; else obj->head = entry->next; release_object( obj ); } /* finish waiting */ static void end_wait( struct thread *thread ) { struct thread_wait *wait = thread->wait; struct wait_queue_entry *entry; int i; assert( wait ); for (i = 0, entry = wait->queues; i < wait->count; i++, entry++) entry->obj->ops->remove_queue( entry->obj, entry ); if (wait->user) remove_timeout_user( wait->user ); thread->wait = wait->next; free( wait ); } /* build the thread wait structure */ static int wait_on( int count, struct object *objects[], int flags, int sec, int usec ) { struct thread_wait *wait; struct wait_queue_entry *entry; int i; if (!(wait = mem_alloc( sizeof(*wait) + (count-1) * sizeof(*entry) ))) return 0; wait->next = current->wait; wait->thread = current; wait->count = count; wait->flags = flags; wait->user = NULL; current->wait = wait; if (flags & SELECT_TIMEOUT) { wait->timeout.tv_sec = sec; wait->timeout.tv_usec = usec; } for (i = 0, entry = wait->queues; i < count; i++, entry++) { struct object *obj = objects[i]; entry->thread = current; if (!obj->ops->add_queue( obj, entry )) { wait->count = i; end_wait( current ); return 0; } } return 1; } /* check if the thread waiting condition is satisfied */ static int check_wait( struct thread *thread ) { int i, signaled; struct thread_wait *wait = thread->wait; struct wait_queue_entry *entry = wait->queues; assert( wait ); if (wait->flags & SELECT_ALL) { int not_ok = 0; /* Note: we must check them all anyway, as some objects may * want to do something when signaled, even if others are not */ for (i = 0, entry = wait->queues; i < wait->count; i++, entry++) not_ok |= !entry->obj->ops->signaled( entry->obj, thread ); if (not_ok) goto other_checks; /* Wait satisfied: tell it to all objects */ signaled = 0; for (i = 0, entry = wait->queues; i < wait->count; i++, entry++) if (entry->obj->ops->satisfied( entry->obj, thread )) signaled = STATUS_ABANDONED_WAIT_0; return signaled; } else { for (i = 0, entry = wait->queues; i < wait->count; i++, entry++) { if (!entry->obj->ops->signaled( entry->obj, thread )) continue; /* Wait satisfied: tell it to the object */ signaled = i; if (entry->obj->ops->satisfied( entry->obj, thread )) signaled = i + STATUS_ABANDONED_WAIT_0; return signaled; } } other_checks: if ((wait->flags & SELECT_INTERRUPTIBLE) && thread->system_apc.head) return STATUS_USER_APC; if ((wait->flags & SELECT_ALERTABLE) && thread->user_apc.head) return STATUS_USER_APC; if (wait->flags & SELECT_TIMEOUT) { struct timeval now; gettimeofday( &now, NULL ); if (!time_before( &now, &wait->timeout )) return STATUS_TIMEOUT; } return -1; } /* send the wakeup signal to a thread */ static int send_thread_wakeup( struct thread *thread, void *cookie, int signaled ) { struct wake_up_reply reply; int ret; reply.cookie = cookie; reply.signaled = signaled; if ((ret = write( thread->wait_fd, &reply, sizeof(reply) )) == sizeof(reply)) return 0; if (ret >= 0) fatal_protocol_error( thread, "partial wakeup write %d\n", ret ); else if (errno == EPIPE) kill_thread( thread, 0 ); /* normal death */ else fatal_protocol_perror( thread, "write" ); return -1; } /* attempt to wake up a thread */ /* return >0 if OK, 0 if the wait condition is still not satisfied */ static int wake_thread( struct thread *thread ) { int signaled, count; void *cookie; for (count = 0; thread->wait; count++) { if ((signaled = check_wait( thread )) == -1) break; cookie = thread->wait->cookie; if (debug_level) fprintf( stderr, "%08x: *wakeup* signaled=%d cookie=%p\n", (unsigned int)thread, signaled, cookie ); end_wait( thread ); if (send_thread_wakeup( thread, cookie, signaled ) == -1) /* error */ break; } return count; } /* thread wait timeout */ static void thread_timeout( void *ptr ) { struct thread_wait *wait = ptr; struct thread *thread = wait->thread; void *cookie = wait->cookie; wait->user = NULL; if (thread->wait != wait) return; /* not the top-level wait, ignore it */ if (debug_level) fprintf( stderr, "%08x: *wakeup* signaled=%d cookie=%p\n", (unsigned int)thread, STATUS_TIMEOUT, cookie ); end_wait( thread ); send_thread_wakeup( thread, cookie, STATUS_TIMEOUT ); /* check if other objects have become signaled in the meantime */ wake_thread( thread ); } /* select on a list of handles */ static void select_on( int count, void *cookie, const handle_t *handles, int flags, int sec, int usec ) { int ret, i; struct object *objects[MAXIMUM_WAIT_OBJECTS]; if ((count < 0) || (count > MAXIMUM_WAIT_OBJECTS)) { set_error( STATUS_INVALID_PARAMETER ); return; } for (i = 0; i < count; i++) { if (!(objects[i] = get_handle_obj( current->process, handles[i], SYNCHRONIZE, NULL ))) break; } if (i < count) goto done; if (!wait_on( count, objects, flags, sec, usec )) goto done; if ((ret = check_wait( current )) != -1) { /* condition is already satisfied */ end_wait( current ); set_error( ret ); goto done; } /* now we need to wait */ if (flags & SELECT_TIMEOUT) { if (!(current->wait->user = add_timeout_user( ¤t->wait->timeout, thread_timeout, current->wait ))) { end_wait( current ); goto done; } } current->wait->cookie = cookie; set_error( STATUS_PENDING ); done: while (--i >= 0) release_object( objects[i] ); } /* attempt to wake threads sleeping on the object wait queue */ void wake_up( struct object *obj, int max ) { struct wait_queue_entry *entry = obj->head; while (entry) { struct thread *thread = entry->thread; entry = entry->next; if (wake_thread( thread )) { if (max && !--max) break; } } } /* queue an async procedure call */ int thread_queue_apc( struct thread *thread, struct object *owner, void *func, enum apc_type type, int system, int nb_args, ... ) { struct thread_apc *apc; struct apc_queue *queue = system ? &thread->system_apc : &thread->user_apc; /* cancel a possible previous APC with the same owner */ if (owner) thread_cancel_apc( thread, owner, system ); if (thread->state == TERMINATED) return 0; if (!(apc = mem_alloc( sizeof(*apc) + (nb_args-1)*sizeof(apc->args[0]) ))) return 0; apc->prev = queue->tail; apc->next = NULL; apc->owner = owner; apc->func = func; apc->type = type; apc->nb_args = nb_args; if (nb_args) { int i; va_list args; va_start( args, nb_args ); for (i = 0; i < nb_args; i++) apc->args[i] = va_arg( args, void * ); va_end( args ); } queue->tail = apc; if (!apc->prev) /* first one */ { queue->head = apc; wake_thread( thread ); } else apc->prev->next = apc; return 1; } /* cancel the async procedure call owned by a specific object */ void thread_cancel_apc( struct thread *thread, struct object *owner, int system ) { struct thread_apc *apc; struct apc_queue *queue = system ? &thread->system_apc : &thread->user_apc; for (apc = queue->head; apc; apc = apc->next) { if (apc->owner != owner) continue; if (apc->next) apc->next->prev = apc->prev; else queue->tail = apc->prev; if (apc->prev) apc->prev->next = apc->next; else queue->head = apc->next; free( apc ); return; } } /* remove the head apc from the queue; the returned pointer must be freed by the caller */ static struct thread_apc *thread_dequeue_apc( struct thread *thread, int system_only ) { struct thread_apc *apc; struct apc_queue *queue = &thread->system_apc; if (!queue->head && !system_only) queue = &thread->user_apc; if ((apc = queue->head)) { if (apc->next) apc->next->prev = NULL; else queue->tail = NULL; queue->head = apc->next; } return apc; } /* add an fd to the inflight list */ /* return list index, or -1 on error */ int thread_add_inflight_fd( struct thread *thread, int client, int server ) { int i; if (server == -1) return -1; if (client == -1) { close( server ); return -1; } /* first check if we already have an entry for this fd */ for (i = 0; i < MAX_INFLIGHT_FDS; i++) if (thread->inflight[i].client == client) { close( thread->inflight[i].server ); thread->inflight[i].server = server; return i; } /* now find a free spot to store it */ for (i = 0; i < MAX_INFLIGHT_FDS; i++) if (thread->inflight[i].client == -1) { thread->inflight[i].client = client; thread->inflight[i].server = server; return i; } return -1; } /* get an inflight fd and purge it from the list */ /* the fd must be closed when no longer used */ int thread_get_inflight_fd( struct thread *thread, int client ) { int i, ret; if (client == -1) return -1; do { for (i = 0; i < MAX_INFLIGHT_FDS; i++) { if (thread->inflight[i].client == client) { ret = thread->inflight[i].server; thread->inflight[i].server = thread->inflight[i].client = -1; return ret; } } } while (!receive_fd( thread->process )); /* in case it is still in the socket buffer */ return -1; } /* retrieve an LDT selector entry */ static void get_selector_entry( struct thread *thread, int entry, unsigned int *base, unsigned int *limit, unsigned char *flags ) { if (!thread->process->ldt_copy) { set_error( STATUS_ACCESS_DENIED ); return; } if (entry >= 8192) { set_error( STATUS_INVALID_PARAMETER ); /* FIXME */ return; } if (suspend_for_ptrace( thread )) { unsigned char flags_buf[4]; int *addr = (int *)thread->process->ldt_copy + entry; if (read_thread_int( thread, addr, base ) == -1) goto done; if (read_thread_int( thread, addr + 8192, limit ) == -1) goto done; addr = (int *)thread->process->ldt_copy + 2*8192 + (entry >> 2); if (read_thread_int( thread, addr, (int *)flags_buf ) == -1) goto done; *flags = flags_buf[entry & 3]; done: resume_thread( thread ); } } /* kill a thread on the spot */ void kill_thread( struct thread *thread, int violent_death ) { if (thread->state == TERMINATED) return; /* already killed */ thread->state = TERMINATED; if (current == thread) current = NULL; if (debug_level) fprintf( stderr,"%08x: *killed* exit_code=%d\n", (unsigned int)thread, thread->exit_code ); if (thread->wait) { while (thread->wait) end_wait( thread ); send_thread_wakeup( thread, NULL, STATUS_PENDING ); /* if it is waiting on the socket, we don't need to send a SIGTERM */ violent_death = 0; } kill_console_processes( thread, 0 ); debug_exit_thread( thread ); abandon_mutexes( thread ); remove_process_thread( thread->process, thread ); wake_up( &thread->obj, 0 ); detach_thread( thread, violent_death ? SIGTERM : 0 ); if (thread->request_fd == thread->obj.fd) thread->request_fd = -1; if (thread->reply_fd == thread->obj.fd) thread->reply_fd = -1; remove_select_user( &thread->obj ); cleanup_thread( thread ); release_object( thread ); } /* take a snapshot of currently running threads */ struct thread_snapshot *thread_snap( int *count ) { struct thread_snapshot *snapshot, *ptr; struct thread *thread; int total = 0; for (thread = first_thread; thread; thread = thread->next) if (thread->state != TERMINATED) total++; if (!total || !(snapshot = mem_alloc( sizeof(*snapshot) * total ))) return NULL; ptr = snapshot; for (thread = first_thread; thread; thread = thread->next) { if (thread->state == TERMINATED) continue; ptr->thread = thread; ptr->count = thread->obj.refcount; ptr->priority = thread->priority; grab_object( thread ); ptr++; } *count = total; return snapshot; } /* signal that we are finished booting on the client side */ DECL_HANDLER(boot_done) { debug_level = max( debug_level, req->debug_level ); if (current == booting_thread) { booting_thread = (struct thread *)~0UL; /* make sure it doesn't match other threads */ lock_master_socket(0); /* allow other clients now */ } } /* create a new thread */ DECL_HANDLER(new_thread) { struct thread *thread; int request_fd = thread_get_inflight_fd( current, req->request_fd ); if (request_fd == -1 || fcntl( request_fd, F_SETFL, O_NONBLOCK ) == -1) { if (request_fd != -1) close( request_fd ); set_error( STATUS_INVALID_HANDLE ); return; } if ((thread = create_thread( request_fd, current->process ))) { if (req->suspend) thread->suspend++; reply->tid = thread; if ((reply->handle = alloc_handle( current->process, thread, THREAD_ALL_ACCESS, req->inherit ))) { /* thread object will be released when the thread gets killed */ return; } kill_thread( thread, 1 ); request_fd = -1; } } /* initialize a new thread */ DECL_HANDLER(init_thread) { int reply_fd = thread_get_inflight_fd( current, req->reply_fd ); int wait_fd = thread_get_inflight_fd( current, req->wait_fd ); if (current->unix_pid) { fatal_protocol_error( current, "init_thread: already running\n" ); goto error; } if (reply_fd == -1 || fcntl( reply_fd, F_SETFL, O_NONBLOCK ) == -1) { fatal_protocol_error( current, "bad reply fd\n" ); goto error; } if (wait_fd == -1) { fatal_protocol_error( current, "bad wait fd\n" ); goto error; } current->unix_pid = req->unix_pid; current->teb = req->teb; current->reply_fd = reply_fd; current->wait_fd = wait_fd; if (current->suspend + current->process->suspend > 0) stop_thread( current ); if (current->process->running_threads > 1) generate_debug_event( current, CREATE_THREAD_DEBUG_EVENT, req->entry ); reply->pid = get_process_id( current->process ); reply->tid = get_thread_id( current ); reply->boot = (current == booting_thread); reply->version = SERVER_PROTOCOL_VERSION; return; error: if (reply_fd != -1) close( reply_fd ); if (wait_fd != -1) close( wait_fd ); } /* terminate a thread */ DECL_HANDLER(terminate_thread) { struct thread *thread; reply->self = 0; reply->last = 0; if ((thread = get_thread_from_handle( req->handle, THREAD_TERMINATE ))) { thread->exit_code = req->exit_code; if (thread != current) kill_thread( thread, 1 ); else { reply->self = 1; reply->last = (thread->process->running_threads == 1); } release_object( thread ); } } /* open a handle to a thread */ DECL_HANDLER(open_thread) { struct thread *thread = get_thread_from_id( req->tid ); reply->handle = 0; if (thread) { reply->handle = alloc_handle( current->process, thread, req->access, req->inherit ); release_object( thread ); } } /* fetch information about a thread */ DECL_HANDLER(get_thread_info) { struct thread *thread; handle_t handle = req->handle; if (!handle) thread = get_thread_from_id( req->tid_in ); else thread = get_thread_from_handle( req->handle, THREAD_QUERY_INFORMATION ); if (thread) { reply->tid = get_thread_id( thread ); reply->teb = thread->teb; reply->exit_code = (thread->state == TERMINATED) ? thread->exit_code : STILL_ACTIVE; reply->priority = thread->priority; release_object( thread ); } } /* set information about a thread */ DECL_HANDLER(set_thread_info) { struct thread *thread; if ((thread = get_thread_from_handle( req->handle, THREAD_SET_INFORMATION ))) { set_thread_info( thread, req ); release_object( thread ); } } /* suspend a thread */ DECL_HANDLER(suspend_thread) { struct thread *thread; if ((thread = get_thread_from_handle( req->handle, THREAD_SUSPEND_RESUME ))) { if (thread->state == TERMINATED) set_error( STATUS_ACCESS_DENIED ); else reply->count = suspend_thread( thread, 1 ); release_object( thread ); } } /* resume a thread */ DECL_HANDLER(resume_thread) { struct thread *thread; if ((thread = get_thread_from_handle( req->handle, THREAD_SUSPEND_RESUME ))) { if (thread->state == TERMINATED) set_error( STATUS_ACCESS_DENIED ); else reply->count = resume_thread( thread ); release_object( thread ); } } /* select on a handle list */ DECL_HANDLER(select) { int count = get_req_data_size() / sizeof(int); select_on( count, req->cookie, get_req_data(), req->flags, req->sec, req->usec ); } /* queue an APC for a thread */ DECL_HANDLER(queue_apc) { struct thread *thread; if ((thread = get_thread_from_handle( req->handle, THREAD_SET_CONTEXT ))) { thread_queue_apc( thread, NULL, req->func, APC_USER, !req->user, 1, req->param ); release_object( thread ); } } /* get next APC to call */ DECL_HANDLER(get_apc) { struct thread_apc *apc; size_t size; for (;;) { if (!(apc = thread_dequeue_apc( current, !req->alertable ))) { /* no more APCs */ reply->func = NULL; reply->type = APC_NONE; return; } /* Optimization: ignore APCs that have a NULL func; they are only used * to wake up a thread, but since we got here the thread woke up already. * Exception: for APC_ASYNC_IO, func == NULL is legal. */ if (apc->func || apc->type == APC_ASYNC_IO) break; free( apc ); } size = apc->nb_args * sizeof(apc->args[0]); if (size > get_reply_max_size()) size = get_reply_max_size(); reply->func = apc->func; reply->type = apc->type; set_reply_data( apc->args, size ); free( apc ); } /* fetch a selector entry for a thread */ DECL_HANDLER(get_selector_entry) { struct thread *thread; if ((thread = get_thread_from_handle( req->handle, THREAD_QUERY_INFORMATION ))) { get_selector_entry( thread, req->entry, &reply->base, &reply->limit, &reply->flags ); release_object( thread ); } }