2 * Server-side thread management
4 * Copyright (C) 1998 Alexandre Julliard
15 #ifdef HAVE_SYS_MMAN_H
18 #include <sys/types.h>
19 #ifdef HAVE_SYS_SOCKET_H
20 # include <sys/socket.h>
37 struct wait_queue_entry
39 struct wait_queue_entry
*next
;
40 struct wait_queue_entry
*prev
;
42 struct thread
*thread
;
47 int count
; /* count of objects */
49 struct timeval timeout
;
50 struct timeout_user
*user
;
51 sleep_reply reply
; /* function to build the reply */
52 struct wait_queue_entry queues
[1];
55 /* asynchronous procedure calls */
59 void *func
; /* function to call in client */
60 void *param
; /* function param */
62 #define MAX_THREAD_APC 16 /* Max outstanding APCs for a thread */
65 /* thread operations */
67 static void dump_thread( struct object
*obj
, int verbose
);
68 static int thread_signaled( struct object
*obj
, struct thread
*thread
);
69 extern void thread_poll_event( struct object
*obj
, int event
);
70 static void destroy_thread( struct object
*obj
);
72 static const struct object_ops thread_ops
=
74 sizeof(struct thread
), /* size */
75 dump_thread
, /* dump */
76 add_queue
, /* add_queue */
77 remove_queue
, /* remove_queue */
78 thread_signaled
, /* signaled */
79 no_satisfied
, /* satisfied */
80 NULL
, /* get_poll_events */
81 thread_poll_event
, /* poll_event */
82 no_read_fd
, /* get_read_fd */
83 no_write_fd
, /* get_write_fd */
85 no_get_file_info
, /* get_file_info */
86 destroy_thread
/* destroy */
89 static struct thread
*first_thread
;
90 static struct thread
*booting_thread
;
92 /* allocate the buffer for the communication with the client */
93 static int alloc_client_buffer( struct thread
*thread
)
97 if ((fd
= create_anonymous_file()) == -1) return -1;
98 if (ftruncate( fd
, MAX_REQUEST_LENGTH
) == -1) goto error
;
99 if ((thread
->buffer
= mmap( 0, MAX_REQUEST_LENGTH
, PROT_READ
| PROT_WRITE
,
100 MAP_SHARED
, fd
, 0 )) == (void*)-1) goto error
;
105 if (fd
!= -1) close( fd
);
109 /* create a new thread */
110 struct thread
*create_thread( int fd
, struct process
*process
, int suspend
)
112 struct thread
*thread
;
115 int flags
= fcntl( fd
, F_GETFL
, 0 );
116 fcntl( fd
, F_SETFL
, flags
| O_NONBLOCK
);
118 if (!(thread
= alloc_object( &thread_ops
, fd
))) return NULL
;
120 thread
->unix_pid
= 0; /* not known yet */
122 thread
->mutex
= NULL
;
123 thread
->debug_ctx
= NULL
;
126 thread
->apc_count
= 0;
128 thread
->pass_fd
= -1;
129 thread
->state
= RUNNING
;
130 thread
->attached
= 0;
131 thread
->exit_code
= STILL_ACTIVE
;
134 thread
->priority
= THREAD_PRIORITY_NORMAL
;
135 thread
->affinity
= 1;
136 thread
->suspend
= (suspend
!= 0);
137 thread
->buffer
= (void *)-1;
138 thread
->last_req
= REQ_GET_THREAD_BUFFER
;
139 thread
->process
= (struct process
*)grab_object( process
);
141 if (!current
) current
= thread
;
143 if (!booting_thread
) /* first thread ever */
145 booting_thread
= thread
;
146 lock_master_socket(1);
149 if ((thread
->next
= first_thread
) != NULL
) thread
->next
->prev
= thread
;
150 first_thread
= thread
;
151 add_process_thread( process
, thread
);
153 if ((buf_fd
= alloc_client_buffer( thread
)) == -1) goto error
;
155 set_select_events( &thread
->obj
, POLLIN
); /* start listening to events */
156 set_reply_fd( thread
, buf_fd
); /* send the fd to the client */
157 send_reply( thread
);
161 remove_process_thread( process
, thread
);
162 release_object( thread
);
166 /* handle a client event */
167 void thread_poll_event( struct object
*obj
, int event
)
169 struct thread
*thread
= (struct thread
*)obj
;
170 assert( obj
->ops
== &thread_ops
);
172 if (event
& (POLLERR
| POLLHUP
)) kill_thread( thread
, BROKEN_PIPE
);
175 if (event
& POLLOUT
) write_request( thread
);
176 if (event
& POLLIN
) read_request( thread
);
180 /* destroy a thread when its refcount is 0 */
181 static void destroy_thread( struct object
*obj
)
183 struct thread
*thread
= (struct thread
*)obj
;
184 assert( obj
->ops
== &thread_ops
);
186 assert( !thread
->debug_ctx
); /* cannot still be debugging something */
187 release_object( thread
->process
);
188 if (thread
->next
) thread
->next
->prev
= thread
->prev
;
189 if (thread
->prev
) thread
->prev
->next
= thread
->next
;
190 else first_thread
= thread
->next
;
191 if (thread
->apc
) free( thread
->apc
);
192 if (thread
->buffer
!= (void *)-1) munmap( thread
->buffer
, MAX_REQUEST_LENGTH
);
193 if (thread
->pass_fd
!= -1) close( thread
->pass_fd
);
196 /* dump a thread on stdout for debugging purposes */
197 static void dump_thread( struct object
*obj
, int verbose
)
199 struct thread
*thread
= (struct thread
*)obj
;
200 assert( obj
->ops
== &thread_ops
);
202 fprintf( stderr
, "Thread pid=%d teb=%p state=%d\n",
203 thread
->unix_pid
, thread
->teb
, thread
->state
);
206 static int thread_signaled( struct object
*obj
, struct thread
*thread
)
208 struct thread
*mythread
= (struct thread
*)obj
;
209 return (mythread
->state
== TERMINATED
);
212 /* get a thread pointer from a thread id (and increment the refcount) */
213 struct thread
*get_thread_from_id( void *id
)
215 struct thread
*t
= first_thread
;
216 while (t
&& (t
!= id
)) t
= t
->next
;
217 if (t
) grab_object( t
);
221 /* get a thread from a handle (and increment the refcount) */
222 struct thread
*get_thread_from_handle( int handle
, unsigned int access
)
224 return (struct thread
*)get_handle_obj( current
->process
, handle
,
225 access
, &thread_ops
);
228 /* find a thread from a Unix pid */
229 struct thread
*get_thread_from_pid( int pid
)
231 struct thread
*t
= first_thread
;
232 while (t
&& (t
->unix_pid
!= pid
)) t
= t
->next
;
236 /* set all information about a thread */
237 static void set_thread_info( struct thread
*thread
,
238 struct set_thread_info_request
*req
)
240 if (req
->mask
& SET_THREAD_INFO_PRIORITY
)
241 thread
->priority
= req
->priority
;
242 if (req
->mask
& SET_THREAD_INFO_AFFINITY
)
244 if (req
->affinity
!= 1) set_error( STATUS_INVALID_PARAMETER
);
245 else thread
->affinity
= req
->affinity
;
249 /* suspend a thread */
250 int suspend_thread( struct thread
*thread
, int check_limit
)
252 int old_count
= thread
->suspend
;
253 if (thread
->suspend
< MAXIMUM_SUSPEND_COUNT
|| !check_limit
)
255 if (!(thread
->process
->suspend
+ thread
->suspend
++)) stop_thread( thread
);
257 else set_error( STATUS_SUSPEND_COUNT_EXCEEDED
);
261 /* resume a thread */
262 int resume_thread( struct thread
*thread
)
264 int old_count
= thread
->suspend
;
265 if (thread
->suspend
> 0)
267 if (!(--thread
->suspend
+ thread
->process
->suspend
)) continue_thread( thread
);
272 /* suspend all threads but the current */
273 void suspend_all_threads( void )
275 struct thread
*thread
;
276 for ( thread
= first_thread
; thread
; thread
= thread
->next
)
277 if ( thread
!= current
)
278 suspend_thread( thread
, 0 );
281 /* resume all threads but the current */
282 void resume_all_threads( void )
284 struct thread
*thread
;
285 for ( thread
= first_thread
; thread
; thread
= thread
->next
)
286 if ( thread
!= current
)
287 resume_thread( thread
);
290 /* add a thread to an object wait queue; return 1 if OK, 0 on error */
291 int add_queue( struct object
*obj
, struct wait_queue_entry
*entry
)
295 entry
->prev
= obj
->tail
;
297 if (obj
->tail
) obj
->tail
->next
= entry
;
298 else obj
->head
= entry
;
303 /* remove a thread from an object wait queue */
304 void remove_queue( struct object
*obj
, struct wait_queue_entry
*entry
)
306 if (entry
->next
) entry
->next
->prev
= entry
->prev
;
307 else obj
->tail
= entry
->prev
;
308 if (entry
->prev
) entry
->prev
->next
= entry
->next
;
309 else obj
->head
= entry
->next
;
310 release_object( obj
);
314 static void end_wait( struct thread
*thread
)
316 struct thread_wait
*wait
= thread
->wait
;
317 struct wait_queue_entry
*entry
;
321 for (i
= 0, entry
= wait
->queues
; i
< wait
->count
; i
++, entry
++)
322 entry
->obj
->ops
->remove_queue( entry
->obj
, entry
);
323 if (wait
->user
) remove_timeout_user( wait
->user
);
328 /* build the thread wait structure */
329 static int wait_on( int count
, struct object
*objects
[], int flags
,
330 int timeout
, sleep_reply func
)
332 struct thread_wait
*wait
;
333 struct wait_queue_entry
*entry
;
336 if (!(wait
= mem_alloc( sizeof(*wait
) + (count
-1) * sizeof(*entry
) ))) return 0;
337 current
->wait
= wait
;
342 if (flags
& SELECT_TIMEOUT
)
344 gettimeofday( &wait
->timeout
, 0 );
345 add_timeout( &wait
->timeout
, timeout
);
348 for (i
= 0, entry
= wait
->queues
; i
< count
; i
++, entry
++)
350 struct object
*obj
= objects
[i
];
351 entry
->thread
= current
;
352 if (!obj
->ops
->add_queue( obj
, entry
))
362 /* check if the thread waiting condition is satisfied */
363 static int check_wait( struct thread
*thread
, struct object
**object
)
366 struct thread_wait
*wait
= thread
->wait
;
367 struct wait_queue_entry
*entry
= wait
->queues
;
371 if (wait
->flags
& SELECT_ALL
)
374 /* Note: we must check them all anyway, as some objects may
375 * want to do something when signaled, even if others are not */
376 for (i
= 0, entry
= wait
->queues
; i
< wait
->count
; i
++, entry
++)
377 not_ok
|= !entry
->obj
->ops
->signaled( entry
->obj
, thread
);
378 if (not_ok
) goto other_checks
;
379 /* Wait satisfied: tell it to all objects */
381 for (i
= 0, entry
= wait
->queues
; i
< wait
->count
; i
++, entry
++)
382 if (entry
->obj
->ops
->satisfied( entry
->obj
, thread
))
383 signaled
= STATUS_ABANDONED_WAIT_0
;
388 for (i
= 0, entry
= wait
->queues
; i
< wait
->count
; i
++, entry
++)
390 if (!entry
->obj
->ops
->signaled( entry
->obj
, thread
)) continue;
391 /* Wait satisfied: tell it to the object */
393 *object
= entry
->obj
;
394 if (entry
->obj
->ops
->satisfied( entry
->obj
, thread
))
395 signaled
= i
+ STATUS_ABANDONED_WAIT_0
;
401 if ((wait
->flags
& SELECT_ALERTABLE
) && thread
->apc
) return STATUS_USER_APC
;
402 if (wait
->flags
& SELECT_TIMEOUT
)
405 gettimeofday( &now
, NULL
);
406 if (!time_before( &now
, &wait
->timeout
)) return STATUS_TIMEOUT
;
411 /* build a reply to the select request */
412 static void build_select_reply( struct thread
*thread
, struct object
*obj
, int signaled
)
414 struct select_request
*req
= get_req_ptr( thread
);
415 req
->signaled
= signaled
;
418 /* attempt to wake up a thread */
419 /* return 1 if OK, 0 if the wait condition is still not satisfied */
420 static int wake_thread( struct thread
*thread
)
423 struct object
*object
;
424 if ((signaled
= check_wait( thread
, &object
)) == -1) return 0;
426 thread
->wait
->reply( thread
, object
, signaled
);
431 /* thread wait timeout */
432 static void thread_timeout( void *ptr
)
434 struct thread
*thread
= ptr
;
435 if (debug_level
) fprintf( stderr
, "%08x: *timeout*\n", (unsigned int)thread
);
436 assert( thread
->wait
);
438 thread
->wait
->user
= NULL
;
439 thread
->wait
->reply( thread
, NULL
, STATUS_TIMEOUT
);
441 send_reply( thread
);
444 /* sleep on a list of objects */
445 int sleep_on( int count
, struct object
*objects
[], int flags
, int timeout
, sleep_reply func
)
447 assert( !current
->wait
);
448 if (!wait_on( count
, objects
, flags
, timeout
, func
)) return 0;
449 if (wake_thread( current
)) return 1;
450 /* now we need to wait */
451 if (flags
& SELECT_TIMEOUT
)
453 if (!(current
->wait
->user
= add_timeout_user( ¤t
->wait
->timeout
,
454 thread_timeout
, current
)))
463 /* select on a list of handles */
464 static int select_on( int count
, int *handles
, int flags
, int timeout
)
468 struct object
*objects
[MAXIMUM_WAIT_OBJECTS
];
470 if ((count
< 0) || (count
> MAXIMUM_WAIT_OBJECTS
))
472 set_error( STATUS_INVALID_PARAMETER
);
475 for (i
= 0; i
< count
; i
++)
477 if (!(objects
[i
] = get_handle_obj( current
->process
, handles
[i
], SYNCHRONIZE
, NULL
)))
480 if (i
== count
) ret
= sleep_on( count
, objects
, flags
, timeout
, build_select_reply
);
481 while (--i
>= 0) release_object( objects
[i
] );
485 /* attempt to wake threads sleeping on the object wait queue */
486 void wake_up( struct object
*obj
, int max
)
488 struct wait_queue_entry
*entry
= obj
->head
;
492 struct thread
*thread
= entry
->thread
;
494 if (wake_thread( thread
))
496 send_reply( thread
);
497 if (max
&& !--max
) break;
502 /* queue an async procedure call */
503 static int thread_queue_apc( struct thread
*thread
, void *func
, void *param
)
505 struct thread_apc
*apc
;
508 if (!(thread
->apc
= mem_alloc( MAX_THREAD_APC
* sizeof(*apc
) )))
510 thread
->apc_count
= 0;
512 else if (thread
->apc_count
>= MAX_THREAD_APC
) return 0;
513 thread
->apc
[thread
->apc_count
].func
= func
;
514 thread
->apc
[thread
->apc_count
].param
= param
;
518 if (wake_thread( thread
)) send_reply( thread
);
523 /* retrieve an LDT selector entry */
524 static void get_selector_entry( struct thread
*thread
, int entry
,
525 unsigned int *base
, unsigned int *limit
,
526 unsigned char *flags
)
528 if (!thread
->process
->ldt_copy
|| !thread
->process
->ldt_flags
)
530 set_error( STATUS_ACCESS_DENIED
);
535 set_error( STATUS_INVALID_PARAMETER
); /* FIXME */
538 suspend_thread( thread
, 0 );
539 if (thread
->attached
)
541 unsigned char flags_buf
[4];
542 int *addr
= (int *)thread
->process
->ldt_copy
+ 2 * entry
;
543 if (read_thread_int( thread
, addr
, base
) == -1) goto done
;
544 if (read_thread_int( thread
, addr
+ 1, limit
) == -1) goto done
;
545 addr
= (int *)thread
->process
->ldt_flags
+ (entry
>> 2);
546 if (read_thread_int( thread
, addr
, (int *)flags_buf
) == -1) goto done
;
547 *flags
= flags_buf
[entry
& 3];
549 else set_error( STATUS_ACCESS_DENIED
);
551 resume_thread( thread
);
554 /* kill a thread on the spot */
555 void kill_thread( struct thread
*thread
, int exit_code
)
557 if (thread
->state
== TERMINATED
) return; /* already killed */
558 thread
->state
= TERMINATED
;
559 thread
->exit_code
= exit_code
;
560 if (current
== thread
) current
= NULL
;
561 if (debug_level
) trace_kill( thread
);
562 if (thread
->wait
) end_wait( thread
);
563 debug_exit_thread( thread
, exit_code
);
564 abandon_mutexes( thread
);
565 remove_process_thread( thread
->process
, thread
);
566 wake_up( &thread
->obj
, 0 );
567 detach_thread( thread
);
568 remove_select_user( &thread
->obj
);
569 release_object( thread
);
572 /* signal that we are finished booting on the client side */
573 DECL_HANDLER(boot_done
)
575 debug_level
= req
->debug_level
;
576 /* Make sure last_req is initialized */
577 current
->last_req
= REQ_BOOT_DONE
;
578 if (current
== booting_thread
)
580 booting_thread
= (struct thread
*)~0UL; /* make sure it doesn't match other threads */
581 lock_master_socket(0); /* allow other clients now */
585 /* create a new thread */
586 DECL_HANDLER(new_thread
)
588 struct thread
*thread
;
591 if (socketpair( AF_UNIX
, SOCK_STREAM
, 0, sock
) != -1)
593 if ((thread
= create_thread( sock
[0], current
->process
, req
->suspend
)))
596 if ((req
->handle
= alloc_handle( current
->process
, thread
,
597 THREAD_ALL_ACCESS
, req
->inherit
)) != -1)
599 set_reply_fd( current
, sock
[1] );
600 /* thread object will be released when the thread gets killed */
603 release_object( thread
);
607 else file_set_error();
610 /* retrieve the thread buffer file descriptor */
611 DECL_HANDLER(get_thread_buffer
)
613 fatal_protocol_error( current
, "get_thread_buffer: should never get called directly\n" );
616 /* initialize a new thread */
617 DECL_HANDLER(init_thread
)
619 if (current
->unix_pid
)
621 fatal_protocol_error( current
, "init_thread: already running\n" );
624 current
->unix_pid
= req
->unix_pid
;
625 current
->teb
= req
->teb
;
626 if (current
->suspend
+ current
->process
->suspend
> 0) stop_thread( current
);
627 req
->pid
= current
->process
;
629 req
->boot
= (current
== booting_thread
);
632 /* terminate a thread */
633 DECL_HANDLER(terminate_thread
)
635 struct thread
*thread
;
637 if ((thread
= get_thread_from_handle( req
->handle
, THREAD_TERMINATE
)))
639 kill_thread( thread
, req
->exit_code
);
640 release_object( thread
);
644 /* fetch information about a thread */
645 DECL_HANDLER(get_thread_info
)
647 struct thread
*thread
;
649 if ((thread
= get_thread_from_handle( req
->handle
, THREAD_QUERY_INFORMATION
)))
652 req
->exit_code
= thread
->exit_code
;
653 req
->priority
= thread
->priority
;
654 release_object( thread
);
658 /* set information about a thread */
659 DECL_HANDLER(set_thread_info
)
661 struct thread
*thread
;
663 if ((thread
= get_thread_from_handle( req
->handle
, THREAD_SET_INFORMATION
)))
665 set_thread_info( thread
, req
);
666 release_object( thread
);
670 /* suspend a thread */
671 DECL_HANDLER(suspend_thread
)
673 struct thread
*thread
;
675 if ((thread
= get_thread_from_handle( req
->handle
, THREAD_SUSPEND_RESUME
)))
677 req
->count
= suspend_thread( thread
, 1 );
678 release_object( thread
);
682 /* resume a thread */
683 DECL_HANDLER(resume_thread
)
685 struct thread
*thread
;
687 if ((thread
= get_thread_from_handle( req
->handle
, THREAD_SUSPEND_RESUME
)))
689 req
->count
= resume_thread( thread
);
690 release_object( thread
);
694 /* select on a handle list */
697 if (!select_on( req
->count
, req
->handles
, req
->flags
, req
->timeout
))
701 /* queue an APC for a thread */
702 DECL_HANDLER(queue_apc
)
704 struct thread
*thread
;
705 if ((thread
= get_thread_from_handle( req
->handle
, THREAD_SET_CONTEXT
)))
707 thread_queue_apc( thread
, req
->func
, req
->param
);
708 release_object( thread
);
712 /* get list of APC to call */
713 DECL_HANDLER(get_apcs
)
715 if ((req
->count
= current
->apc_count
))
717 memcpy( req
->apcs
, current
->apc
, current
->apc_count
* sizeof(*current
->apc
) );
718 free( current
->apc
);
720 current
->apc_count
= 0;
724 /* fetch a selector entry for a thread */
725 DECL_HANDLER(get_selector_entry
)
727 struct thread
*thread
;
728 if ((thread
= get_thread_from_handle( req
->handle
, THREAD_QUERY_INFORMATION
)))
730 get_selector_entry( thread
, req
->entry
, &req
->base
, &req
->limit
, &req
->flags
);
731 release_object( thread
);