2 * Server-side handle management
4 * Copyright (C) 1998 Alexandre Julliard
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.
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.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include "wine/port.h"
40 struct object
*ptr
; /* object */
41 unsigned int access
; /* access rights */
42 int fd
; /* file descriptor (in client process) */
47 struct object obj
; /* object header */
48 struct process
*process
; /* process owning this table */
49 int count
; /* number of allocated entries */
50 int last
; /* last used entry */
51 int free
; /* first entry that may be free */
52 struct handle_entry
*entries
; /* handle entries */
55 static struct handle_table
*global_table
;
57 /* reserved handle access rights */
58 #define RESERVED_SHIFT 26
59 #define RESERVED_INHERIT (HANDLE_FLAG_INHERIT << RESERVED_SHIFT)
60 #define RESERVED_CLOSE_PROTECT (HANDLE_FLAG_PROTECT_FROM_CLOSE << RESERVED_SHIFT)
61 #define RESERVED_ALL (RESERVED_INHERIT | RESERVED_CLOSE_PROTECT)
63 #define MIN_HANDLE_ENTRIES 32
66 /* handle to table index conversion */
68 /* handles are a multiple of 4 under NT; handle 0 is not used */
69 inline static obj_handle_t
index_to_handle( int index
)
71 return (obj_handle_t
)((index
+ 1) << 2);
73 inline static int handle_to_index( obj_handle_t handle
)
75 return ((unsigned int)handle
>> 2) - 1;
78 /* global handle conversion */
80 #define HANDLE_OBFUSCATOR 0x544a4def
82 inline static int handle_is_global( obj_handle_t handle
)
84 return ((unsigned long)handle
^ HANDLE_OBFUSCATOR
) < 0x10000;
86 inline static obj_handle_t
handle_local_to_global( obj_handle_t handle
)
88 if (!handle
) return 0;
89 return (obj_handle_t
)((unsigned long)handle
^ HANDLE_OBFUSCATOR
);
91 inline static obj_handle_t
handle_global_to_local( obj_handle_t handle
)
93 return (obj_handle_t
)((unsigned long)handle
^ HANDLE_OBFUSCATOR
);
97 static void handle_table_dump( struct object
*obj
, int verbose
);
98 static void handle_table_destroy( struct object
*obj
);
100 static const struct object_ops handle_table_ops
=
102 sizeof(struct handle_table
), /* size */
103 handle_table_dump
, /* dump */
104 no_add_queue
, /* add_queue */
105 NULL
, /* remove_queue */
107 NULL
, /* satisfied */
108 no_signal
, /* signal */
109 no_get_fd
, /* get_fd */
110 no_close_handle
, /* close_handle */
111 handle_table_destroy
/* destroy */
114 /* dump a handle table */
115 static void handle_table_dump( struct object
*obj
, int verbose
)
118 struct handle_table
*table
= (struct handle_table
*)obj
;
119 struct handle_entry
*entry
= table
->entries
;
121 assert( obj
->ops
== &handle_table_ops
);
123 fprintf( stderr
, "Handle table last=%d count=%d process=%p\n",
124 table
->last
, table
->count
, table
->process
);
125 if (!verbose
) return;
126 entry
= table
->entries
;
127 for (i
= 0; i
<= table
->last
; i
++, entry
++)
129 if (!entry
->ptr
) continue;
130 fprintf( stderr
, "%9u: %p %08x ",
131 (unsigned int)index_to_handle(i
), entry
->ptr
, entry
->access
);
132 entry
->ptr
->ops
->dump( entry
->ptr
, 0 );
136 /* destroy a handle table */
137 static void handle_table_destroy( struct object
*obj
)
140 struct handle_table
*table
= (struct handle_table
*)obj
;
141 struct handle_entry
*entry
;
143 assert( obj
->ops
== &handle_table_ops
);
145 /* first notify all objects that handles are being closed */
148 for (i
= 0, entry
= table
->entries
; i
<= table
->last
; i
++, entry
++)
150 struct object
*obj
= entry
->ptr
;
151 if (obj
) obj
->ops
->close_handle( obj
, table
->process
, index_to_handle(i
) );
155 for (i
= 0, entry
= table
->entries
; i
<= table
->last
; i
++, entry
++)
157 struct object
*obj
= entry
->ptr
;
159 if (obj
) release_object( obj
);
161 free( table
->entries
);
164 /* allocate a new handle table */
165 struct handle_table
*alloc_handle_table( struct process
*process
, int count
)
167 struct handle_table
*table
;
169 if (count
< MIN_HANDLE_ENTRIES
) count
= MIN_HANDLE_ENTRIES
;
170 if (!(table
= alloc_object( &handle_table_ops
)))
172 table
->process
= process
;
173 table
->count
= count
;
176 if ((table
->entries
= mem_alloc( count
* sizeof(*table
->entries
) ))) return table
;
177 release_object( table
);
181 /* grow a handle table */
182 static int grow_handle_table( struct handle_table
*table
)
184 struct handle_entry
*new_entries
;
185 int count
= table
->count
;
187 if (count
>= INT_MAX
/ 2) return 0;
189 if (!(new_entries
= realloc( table
->entries
, count
* sizeof(struct handle_entry
) )))
191 set_error( STATUS_NO_MEMORY
);
194 table
->entries
= new_entries
;
195 table
->count
= count
;
199 /* allocate the first free entry in the handle table */
200 static obj_handle_t
alloc_entry( struct handle_table
*table
, void *obj
, unsigned int access
)
202 struct handle_entry
*entry
= table
->entries
+ table
->free
;
205 for (i
= table
->free
; i
<= table
->last
; i
++, entry
++) if (!entry
->ptr
) goto found
;
206 if (i
>= table
->count
)
208 if (!grow_handle_table( table
)) return 0;
209 entry
= table
->entries
+ i
; /* the entries may have moved */
214 entry
->ptr
= grab_object( obj
);
215 entry
->access
= access
;
217 return index_to_handle(i
);
220 /* allocate a handle for an object, incrementing its refcount */
221 /* return the handle, or 0 on error */
222 obj_handle_t
alloc_handle( struct process
*process
, void *obj
, unsigned int access
, int inherit
)
224 struct handle_table
*table
= process
->handles
;
227 assert( !(access
& RESERVED_ALL
) );
228 if (inherit
) access
|= RESERVED_INHERIT
;
229 return alloc_entry( table
, obj
, access
);
232 /* allocate a global handle for an object, incrementing its refcount */
233 /* return the handle, or 0 on error */
234 static obj_handle_t
alloc_global_handle( void *obj
, unsigned int access
)
238 if (!(global_table
= (struct handle_table
*)alloc_handle_table( NULL
, 0 )))
241 return handle_local_to_global( alloc_entry( global_table
, obj
, access
));
244 /* return a handle entry, or NULL if the handle is invalid */
245 static struct handle_entry
*get_handle( struct process
*process
, obj_handle_t handle
)
247 struct handle_table
*table
= process
->handles
;
248 struct handle_entry
*entry
;
251 if (handle_is_global(handle
))
253 handle
= handle_global_to_local(handle
);
254 table
= global_table
;
256 if (!table
) goto error
;
257 index
= handle_to_index( handle
);
258 if (index
< 0) goto error
;
259 if (index
> table
->last
) goto error
;
260 entry
= table
->entries
+ index
;
261 if (!entry
->ptr
) goto error
;
265 set_error( STATUS_INVALID_HANDLE
);
269 /* attempt to shrink a table */
270 static void shrink_handle_table( struct handle_table
*table
)
272 struct handle_entry
*entry
= table
->entries
+ table
->last
;
273 struct handle_entry
*new_entries
;
274 int count
= table
->count
;
276 while (table
->last
>= 0)
278 if (entry
->ptr
) break;
282 if (table
->last
>= count
/ 4) return; /* no need to shrink */
283 if (count
< MIN_HANDLE_ENTRIES
* 2) return; /* too small to shrink */
285 if (!(new_entries
= realloc( table
->entries
, count
* sizeof(*new_entries
) ))) return;
286 table
->count
= count
;
287 table
->entries
= new_entries
;
290 /* copy the handle table of the parent process */
291 /* return 1 if OK, 0 on error */
292 struct handle_table
*copy_handle_table( struct process
*process
, struct process
*parent
)
294 struct handle_table
*parent_table
= parent
->handles
;
295 struct handle_table
*table
;
298 assert( parent_table
);
299 assert( parent_table
->obj
.ops
== &handle_table_ops
);
301 if (!(table
= (struct handle_table
*)alloc_handle_table( process
, parent_table
->count
)))
304 if ((table
->last
= parent_table
->last
) >= 0)
306 struct handle_entry
*ptr
= table
->entries
;
307 memcpy( ptr
, parent_table
->entries
, (table
->last
+ 1) * sizeof(struct handle_entry
) );
308 for (i
= 0; i
<= table
->last
; i
++, ptr
++)
310 if (!ptr
->ptr
) continue;
312 if (ptr
->access
& RESERVED_INHERIT
) grab_object( ptr
->ptr
);
313 else ptr
->ptr
= NULL
; /* don't inherit this entry */
316 /* attempt to shrink the table */
317 shrink_handle_table( table
);
321 /* close a handle and decrement the refcount of the associated object */
322 /* return 1 if OK, 0 on error */
323 int close_handle( struct process
*process
, obj_handle_t handle
, int *fd
)
325 struct handle_table
*table
;
326 struct handle_entry
*entry
;
329 if (!(entry
= get_handle( process
, handle
))) return 0;
330 if (entry
->access
& RESERVED_CLOSE_PROTECT
)
332 set_error( STATUS_INVALID_HANDLE
);
336 if (!obj
->ops
->close_handle( obj
, process
, handle
))
338 set_error( STATUS_INVALID_HANDLE
);
342 if (fd
) *fd
= entry
->fd
;
343 else if (entry
->fd
!= -1) return 1; /* silently ignore close attempt if we cannot close the fd */
345 table
= handle_is_global(handle
) ? global_table
: process
->handles
;
346 if (entry
< table
->entries
+ table
->free
) table
->free
= entry
- table
->entries
;
347 if (entry
== table
->entries
+ table
->last
) shrink_handle_table( table
);
348 release_object( obj
);
352 /* close all the global handles */
353 void close_global_handles(void)
357 release_object( global_table
);
362 /* retrieve the object corresponding to one of the magic pseudo-handles */
363 static inline struct object
*get_magic_handle( obj_handle_t handle
)
365 switch((unsigned long)handle
)
367 case 0xfffffffe: /* current thread pseudo-handle */
368 return ¤t
->obj
;
369 case 0x7fffffff: /* current process pseudo-handle */
370 case 0xffffffff: /* current process pseudo-handle */
371 return (struct object
*)current
->process
;
377 /* retrieve the object corresponding to a handle, incrementing its refcount */
378 struct object
*get_handle_obj( struct process
*process
, obj_handle_t handle
,
379 unsigned int access
, const struct object_ops
*ops
)
381 struct handle_entry
*entry
;
384 if (!(obj
= get_magic_handle( handle
)))
386 if (!(entry
= get_handle( process
, handle
))) return NULL
;
387 if ((entry
->access
& access
) != access
)
389 set_error( STATUS_ACCESS_DENIED
);
394 if (ops
&& (obj
->ops
!= ops
))
396 set_error( STATUS_OBJECT_TYPE_MISMATCH
); /* not the right type */
399 return grab_object( obj
);
402 /* retrieve the access rights of a given handle */
403 unsigned int get_handle_access( struct process
*process
, obj_handle_t handle
)
405 struct handle_entry
*entry
;
407 if (get_magic_handle( handle
)) return ~0U; /* magic handles have all access rights */
408 if (!(entry
= get_handle( process
, handle
))) return 0;
409 return entry
->access
;
412 /* retrieve the cached fd for a given handle */
413 int get_handle_unix_fd( struct process
*process
, obj_handle_t handle
, unsigned int access
)
415 struct handle_entry
*entry
;
417 if (!(entry
= get_handle( process
, handle
))) return -1;
418 if ((entry
->access
& access
) != access
)
420 set_error( STATUS_ACCESS_DENIED
);
426 /* remove the cached fd and return it */
427 int flush_cached_fd( struct process
*process
, obj_handle_t handle
)
429 struct handle_entry
*entry
= get_handle( process
, handle
);
440 /* find the first inherited handle of the given type */
441 /* this is needed for window stations and desktops (don't ask...) */
442 obj_handle_t
find_inherited_handle( struct process
*process
, const struct object_ops
*ops
)
444 struct handle_table
*table
= process
->handles
;
445 struct handle_entry
*ptr
;
448 if (!table
) return 0;
450 for (i
= 0, ptr
= table
->entries
; i
<= table
->last
; i
++, ptr
++)
452 if (!ptr
->ptr
) continue;
453 if (ptr
->ptr
->ops
!= ops
) continue;
454 if (ptr
->access
& RESERVED_INHERIT
) return index_to_handle(i
);
459 /* get/set the handle reserved flags */
460 /* return the old flags (or -1 on error) */
461 int set_handle_info( struct process
*process
, obj_handle_t handle
, int mask
, int flags
, int *fd
)
463 struct handle_entry
*entry
;
464 unsigned int old_access
;
466 if (get_magic_handle( handle
))
468 /* we can retrieve but not set info for magic handles */
469 if (mask
) set_error( STATUS_ACCESS_DENIED
);
472 if (!(entry
= get_handle( process
, handle
))) return -1;
473 old_access
= entry
->access
;
474 mask
= (mask
<< RESERVED_SHIFT
) & RESERVED_ALL
;
475 flags
= (flags
<< RESERVED_SHIFT
) & mask
;
476 entry
->access
= (entry
->access
& ~mask
) | flags
;
477 /* if no current fd set it, otherwise return current fd */
478 if (entry
->fd
== -1) entry
->fd
= *fd
;
480 return (old_access
& RESERVED_ALL
) >> RESERVED_SHIFT
;
483 /* duplicate a handle */
484 obj_handle_t
duplicate_handle( struct process
*src
, obj_handle_t src_handle
, struct process
*dst
,
485 unsigned int access
, int inherit
, int options
)
488 struct object
*obj
= get_handle_obj( src
, src_handle
, 0, NULL
);
491 if (options
& DUP_HANDLE_SAME_ACCESS
)
493 struct handle_entry
*entry
= get_handle( src
, src_handle
);
495 access
= entry
->access
;
496 else /* pseudo-handle, give it full access */
498 access
= STANDARD_RIGHTS_ALL
| SPECIFIC_RIGHTS_ALL
;
502 access
&= ~RESERVED_ALL
;
503 if (options
& DUP_HANDLE_MAKE_GLOBAL
)
504 res
= alloc_global_handle( obj
, access
);
506 res
= alloc_handle( dst
, obj
, access
, inherit
);
507 release_object( obj
);
511 /* open a new handle to an existing object */
512 obj_handle_t
open_object( const struct namespace *namespace, const WCHAR
*name
, size_t len
,
513 const struct object_ops
*ops
, unsigned int access
, int inherit
)
515 obj_handle_t handle
= 0;
516 struct object
*obj
= find_object( namespace, name
, len
);
519 if (ops
&& obj
->ops
!= ops
)
520 set_error( STATUS_OBJECT_TYPE_MISMATCH
);
522 handle
= alloc_handle( current
->process
, obj
, access
, inherit
);
523 release_object( obj
);
526 set_error( STATUS_OBJECT_NAME_NOT_FOUND
);
530 /* return the size of the handle table of a given process */
531 unsigned int get_handle_table_count( struct process
*process
)
533 return process
->handles
->count
;
537 DECL_HANDLER(close_handle
)
539 close_handle( current
->process
, req
->handle
, &reply
->fd
);
542 /* set a handle information */
543 DECL_HANDLER(set_handle_info
)
547 if (handle_is_global(req
->handle
)) fd
= -1; /* no fd cache for global handles */
548 reply
->old_flags
= set_handle_info( current
->process
, req
->handle
,
549 req
->mask
, req
->flags
, &fd
);
553 /* duplicate a handle */
554 DECL_HANDLER(dup_handle
)
556 struct process
*src
, *dst
;
560 if ((src
= get_process_from_handle( req
->src_process
, PROCESS_DUP_HANDLE
)))
562 if (req
->options
& DUP_HANDLE_MAKE_GLOBAL
)
564 reply
->handle
= duplicate_handle( src
, req
->src_handle
, NULL
,
565 req
->access
, req
->inherit
, req
->options
);
567 else if ((dst
= get_process_from_handle( req
->dst_process
, PROCESS_DUP_HANDLE
)))
569 reply
->handle
= duplicate_handle( src
, req
->src_handle
, dst
,
570 req
->access
, req
->inherit
, req
->options
);
571 release_object( dst
);
573 /* close the handle no matter what happened */
574 if (req
->options
& DUP_HANDLE_CLOSE_SOURCE
)
576 if (src
== current
->process
) close_handle( src
, req
->src_handle
, &reply
->fd
);
577 else close_handle( src
, req
->src_handle
, NULL
);
579 release_object( src
);