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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
22 #include "wine/port.h"
32 #define WIN32_NO_STATUS
43 struct object
*ptr
; /* object */
44 unsigned int access
; /* access rights */
45 int fd
; /* file descriptor (in client process) */
50 struct object obj
; /* object header */
51 struct process
*process
; /* process owning this table */
52 int count
; /* number of allocated entries */
53 int last
; /* last used entry */
54 int free
; /* first entry that may be free */
55 struct handle_entry
*entries
; /* handle entries */
58 static struct handle_table
*global_table
;
60 /* reserved handle access rights */
61 #define RESERVED_SHIFT 26
62 #define RESERVED_INHERIT (HANDLE_FLAG_INHERIT << RESERVED_SHIFT)
63 #define RESERVED_CLOSE_PROTECT (HANDLE_FLAG_PROTECT_FROM_CLOSE << RESERVED_SHIFT)
64 #define RESERVED_ALL (RESERVED_INHERIT | RESERVED_CLOSE_PROTECT)
66 #define MIN_HANDLE_ENTRIES 32
69 /* handle to table index conversion */
71 /* handles are a multiple of 4 under NT; handle 0 is not used */
72 inline static obj_handle_t
index_to_handle( int index
)
74 return (obj_handle_t
)((index
+ 1) << 2);
76 inline static int handle_to_index( obj_handle_t handle
)
78 return ((unsigned int)handle
>> 2) - 1;
81 /* global handle conversion */
83 #define HANDLE_OBFUSCATOR 0x544a4def
85 inline static int handle_is_global( obj_handle_t handle
)
87 return ((unsigned long)handle
^ HANDLE_OBFUSCATOR
) < 0x10000;
89 inline static obj_handle_t
handle_local_to_global( obj_handle_t handle
)
91 if (!handle
) return 0;
92 return (obj_handle_t
)((unsigned long)handle
^ HANDLE_OBFUSCATOR
);
94 inline static obj_handle_t
handle_global_to_local( obj_handle_t handle
)
96 return (obj_handle_t
)((unsigned long)handle
^ HANDLE_OBFUSCATOR
);
100 static void handle_table_dump( struct object
*obj
, int verbose
);
101 static void handle_table_destroy( struct object
*obj
);
103 static const struct object_ops handle_table_ops
=
105 sizeof(struct handle_table
), /* size */
106 handle_table_dump
, /* dump */
107 no_add_queue
, /* add_queue */
108 NULL
, /* remove_queue */
110 NULL
, /* satisfied */
111 no_signal
, /* signal */
112 no_get_fd
, /* get_fd */
113 no_map_access
, /* map_access */
114 no_lookup_name
, /* lookup_name */
115 no_close_handle
, /* close_handle */
116 handle_table_destroy
/* destroy */
119 /* dump a handle table */
120 static void handle_table_dump( struct object
*obj
, int verbose
)
123 struct handle_table
*table
= (struct handle_table
*)obj
;
124 struct handle_entry
*entry
= table
->entries
;
126 assert( obj
->ops
== &handle_table_ops
);
128 fprintf( stderr
, "Handle table last=%d count=%d process=%p\n",
129 table
->last
, table
->count
, table
->process
);
130 if (!verbose
) return;
131 entry
= table
->entries
;
132 for (i
= 0; i
<= table
->last
; i
++, entry
++)
134 if (!entry
->ptr
) continue;
135 fprintf( stderr
, " %p: %p %08x ",
136 index_to_handle(i
), entry
->ptr
, entry
->access
);
137 entry
->ptr
->ops
->dump( entry
->ptr
, 0 );
141 /* destroy a handle table */
142 static void handle_table_destroy( struct object
*obj
)
145 struct handle_table
*table
= (struct handle_table
*)obj
;
146 struct handle_entry
*entry
;
148 assert( obj
->ops
== &handle_table_ops
);
150 /* first notify all objects that handles are being closed */
153 for (i
= 0, entry
= table
->entries
; i
<= table
->last
; i
++, entry
++)
155 struct object
*obj
= entry
->ptr
;
156 if (obj
) obj
->ops
->close_handle( obj
, table
->process
, index_to_handle(i
) );
160 for (i
= 0, entry
= table
->entries
; i
<= table
->last
; i
++, entry
++)
162 struct object
*obj
= entry
->ptr
;
164 if (obj
) release_object( obj
);
166 free( table
->entries
);
169 /* allocate a new handle table */
170 struct handle_table
*alloc_handle_table( struct process
*process
, int count
)
172 struct handle_table
*table
;
174 if (count
< MIN_HANDLE_ENTRIES
) count
= MIN_HANDLE_ENTRIES
;
175 if (!(table
= alloc_object( &handle_table_ops
)))
177 table
->process
= process
;
178 table
->count
= count
;
181 if ((table
->entries
= mem_alloc( count
* sizeof(*table
->entries
) ))) return table
;
182 release_object( table
);
186 /* grow a handle table */
187 static int grow_handle_table( struct handle_table
*table
)
189 struct handle_entry
*new_entries
;
190 int count
= table
->count
;
192 if (count
>= INT_MAX
/ 2) return 0;
194 if (!(new_entries
= realloc( table
->entries
, count
* sizeof(struct handle_entry
) )))
196 set_error( STATUS_NO_MEMORY
);
199 table
->entries
= new_entries
;
200 table
->count
= count
;
204 /* allocate the first free entry in the handle table */
205 static obj_handle_t
alloc_entry( struct handle_table
*table
, void *obj
, unsigned int access
)
207 struct handle_entry
*entry
= table
->entries
+ table
->free
;
210 for (i
= table
->free
; i
<= table
->last
; i
++, entry
++) if (!entry
->ptr
) goto found
;
211 if (i
>= table
->count
)
213 if (!grow_handle_table( table
)) return 0;
214 entry
= table
->entries
+ i
; /* the entries may have moved */
219 entry
->ptr
= grab_object( obj
);
220 entry
->access
= access
;
222 return index_to_handle(i
);
225 /* allocate a handle for an object, incrementing its refcount */
226 /* return the handle, or 0 on error */
227 obj_handle_t
alloc_handle( struct process
*process
, void *ptr
, unsigned int access
, unsigned int attr
)
229 struct object
*obj
= ptr
;
231 access
= obj
->ops
->map_access( obj
, access
);
232 access
&= ~RESERVED_ALL
;
233 if (attr
& OBJ_INHERIT
) access
|= RESERVED_INHERIT
;
234 if (!process
->handles
)
236 set_error( STATUS_NO_MEMORY
);
239 return alloc_entry( process
->handles
, obj
, access
);
242 /* allocate a global handle for an object, incrementing its refcount */
243 /* return the handle, or 0 on error */
244 static obj_handle_t
alloc_global_handle( void *obj
, unsigned int access
)
248 if (!(global_table
= (struct handle_table
*)alloc_handle_table( NULL
, 0 )))
250 make_object_static( &global_table
->obj
);
252 return handle_local_to_global( alloc_entry( global_table
, obj
, access
));
255 /* return a handle entry, or NULL if the handle is invalid */
256 static struct handle_entry
*get_handle( struct process
*process
, obj_handle_t handle
)
258 struct handle_table
*table
= process
->handles
;
259 struct handle_entry
*entry
;
262 if (handle_is_global(handle
))
264 handle
= handle_global_to_local(handle
);
265 table
= global_table
;
267 if (!table
) goto error
;
268 index
= handle_to_index( handle
);
269 if (index
< 0) goto error
;
270 if (index
> table
->last
) goto error
;
271 entry
= table
->entries
+ index
;
272 if (!entry
->ptr
) goto error
;
276 set_error( STATUS_INVALID_HANDLE
);
280 /* attempt to shrink a table */
281 static void shrink_handle_table( struct handle_table
*table
)
283 struct handle_entry
*entry
= table
->entries
+ table
->last
;
284 struct handle_entry
*new_entries
;
285 int count
= table
->count
;
287 while (table
->last
>= 0)
289 if (entry
->ptr
) break;
293 if (table
->last
>= count
/ 4) return; /* no need to shrink */
294 if (count
< MIN_HANDLE_ENTRIES
* 2) return; /* too small to shrink */
296 if (!(new_entries
= realloc( table
->entries
, count
* sizeof(*new_entries
) ))) return;
297 table
->count
= count
;
298 table
->entries
= new_entries
;
301 /* copy the handle table of the parent process */
302 /* return 1 if OK, 0 on error */
303 struct handle_table
*copy_handle_table( struct process
*process
, struct process
*parent
)
305 struct handle_table
*parent_table
= parent
->handles
;
306 struct handle_table
*table
;
309 assert( parent_table
);
310 assert( parent_table
->obj
.ops
== &handle_table_ops
);
312 if (!(table
= (struct handle_table
*)alloc_handle_table( process
, parent_table
->count
)))
315 if ((table
->last
= parent_table
->last
) >= 0)
317 struct handle_entry
*ptr
= table
->entries
;
318 memcpy( ptr
, parent_table
->entries
, (table
->last
+ 1) * sizeof(struct handle_entry
) );
319 for (i
= 0; i
<= table
->last
; i
++, ptr
++)
321 if (!ptr
->ptr
) continue;
323 if (ptr
->access
& RESERVED_INHERIT
) grab_object( ptr
->ptr
);
324 else ptr
->ptr
= NULL
; /* don't inherit this entry */
327 /* attempt to shrink the table */
328 shrink_handle_table( table
);
332 /* close a handle and decrement the refcount of the associated object */
333 /* return 1 if OK, 0 on error */
334 int close_handle( struct process
*process
, obj_handle_t handle
, int *fd
)
336 struct handle_table
*table
;
337 struct handle_entry
*entry
;
340 if (!(entry
= get_handle( process
, handle
))) return 0;
341 if (entry
->access
& RESERVED_CLOSE_PROTECT
)
343 set_error( STATUS_HANDLE_NOT_CLOSABLE
);
347 if (!obj
->ops
->close_handle( obj
, process
, handle
))
349 set_error( STATUS_HANDLE_NOT_CLOSABLE
);
353 if (fd
) *fd
= entry
->fd
;
354 else if (entry
->fd
!= -1) return 1; /* silently ignore close attempt if we cannot close the fd */
356 table
= handle_is_global(handle
) ? global_table
: process
->handles
;
357 if (entry
< table
->entries
+ table
->free
) table
->free
= entry
- table
->entries
;
358 if (entry
== table
->entries
+ table
->last
) shrink_handle_table( table
);
359 release_object( obj
);
363 /* retrieve the object corresponding to one of the magic pseudo-handles */
364 static inline struct object
*get_magic_handle( obj_handle_t handle
)
366 switch((unsigned long)handle
)
368 case 0xfffffffe: /* current thread pseudo-handle */
369 return ¤t
->obj
;
370 case 0x7fffffff: /* current process pseudo-handle */
371 case 0xffffffff: /* current process pseudo-handle */
372 return (struct object
*)current
->process
;
378 /* retrieve the object corresponding to a handle, incrementing its refcount */
379 struct object
*get_handle_obj( struct process
*process
, obj_handle_t handle
,
380 unsigned int access
, const struct object_ops
*ops
)
382 struct handle_entry
*entry
;
385 if (!(obj
= get_magic_handle( handle
)))
387 if (!(entry
= get_handle( process
, handle
))) return NULL
;
388 if ((entry
->access
& access
) != access
)
390 set_error( STATUS_ACCESS_DENIED
);
395 if (ops
&& (obj
->ops
!= ops
))
397 set_error( STATUS_OBJECT_TYPE_MISMATCH
); /* not the right type */
400 return grab_object( obj
);
403 /* retrieve the access rights of a given handle */
404 unsigned int get_handle_access( struct process
*process
, obj_handle_t handle
)
406 struct handle_entry
*entry
;
408 if (get_magic_handle( handle
)) return ~0U; /* magic handles have all access rights */
409 if (!(entry
= get_handle( process
, handle
))) return 0;
410 return entry
->access
;
413 /* retrieve the cached fd for a given handle */
414 int get_handle_unix_fd( struct process
*process
, obj_handle_t handle
, unsigned int access
)
416 struct handle_entry
*entry
;
418 if (!(entry
= get_handle( process
, handle
))) return -1;
419 if ((entry
->access
& access
) != access
)
421 set_error( STATUS_ACCESS_DENIED
);
427 /* set the cached fd for a handle if not set already, and return the current value */
428 int set_handle_unix_fd( struct process
*process
, obj_handle_t handle
, int fd
)
430 struct handle_entry
*entry
;
432 if (handle_is_global( handle
)) return -1; /* no fd cache for global handles */
433 if (!(entry
= get_handle( process
, handle
))) return -1;
434 /* if no current fd set it, otherwise return current fd */
435 if (entry
->fd
== -1) entry
->fd
= fd
;
439 /* remove the cached fd and return it */
440 int flush_cached_fd( struct process
*process
, obj_handle_t handle
)
442 struct handle_entry
*entry
= get_handle( process
, handle
);
453 /* find the first inherited handle of the given type */
454 /* this is needed for window stations and desktops (don't ask...) */
455 obj_handle_t
find_inherited_handle( struct process
*process
, const struct object_ops
*ops
)
457 struct handle_table
*table
= process
->handles
;
458 struct handle_entry
*ptr
;
461 if (!table
) return 0;
463 for (i
= 0, ptr
= table
->entries
; i
<= table
->last
; i
++, ptr
++)
465 if (!ptr
->ptr
) continue;
466 if (ptr
->ptr
->ops
!= ops
) continue;
467 if (ptr
->access
& RESERVED_INHERIT
) return index_to_handle(i
);
472 /* get/set the handle reserved flags */
473 /* return the old flags (or -1 on error) */
474 static int set_handle_flags( struct process
*process
, obj_handle_t handle
, int mask
, int flags
)
476 struct handle_entry
*entry
;
477 unsigned int old_access
;
479 if (get_magic_handle( handle
))
481 /* we can retrieve but not set info for magic handles */
482 if (mask
) set_error( STATUS_ACCESS_DENIED
);
485 if (!(entry
= get_handle( process
, handle
))) return -1;
486 old_access
= entry
->access
;
487 mask
= (mask
<< RESERVED_SHIFT
) & RESERVED_ALL
;
488 flags
= (flags
<< RESERVED_SHIFT
) & mask
;
489 entry
->access
= (entry
->access
& ~mask
) | flags
;
490 return (old_access
& RESERVED_ALL
) >> RESERVED_SHIFT
;
493 /* duplicate a handle */
494 obj_handle_t
duplicate_handle( struct process
*src
, obj_handle_t src_handle
, struct process
*dst
,
495 unsigned int access
, unsigned int attr
, unsigned int options
)
498 struct object
*obj
= get_handle_obj( src
, src_handle
, 0, NULL
);
501 if (options
& DUP_HANDLE_SAME_ACCESS
)
503 struct handle_entry
*entry
= get_handle( src
, src_handle
);
505 access
= entry
->access
;
506 else /* pseudo-handle, give it full access */
508 access
= STANDARD_RIGHTS_ALL
| SPECIFIC_RIGHTS_ALL
;
512 access
&= ~RESERVED_ALL
;
513 if (options
& DUP_HANDLE_MAKE_GLOBAL
)
514 res
= alloc_global_handle( obj
, access
);
516 res
= alloc_handle( dst
, obj
, access
, attr
);
517 release_object( obj
);
521 /* open a new handle to an existing object */
522 obj_handle_t
open_object( const struct namespace *namespace, const struct unicode_str
*name
,
523 const struct object_ops
*ops
, unsigned int access
, unsigned int attr
)
525 obj_handle_t handle
= 0;
526 struct object
*obj
= find_object( namespace, name
, attr
);
529 if (ops
&& obj
->ops
!= ops
)
530 set_error( STATUS_OBJECT_TYPE_MISMATCH
);
532 handle
= alloc_handle( current
->process
, obj
, access
, attr
);
533 release_object( obj
);
536 set_error( STATUS_OBJECT_NAME_NOT_FOUND
);
540 /* return the size of the handle table of a given process */
541 unsigned int get_handle_table_count( struct process
*process
)
543 if (!process
->handles
) return 0;
544 return process
->handles
->count
;
548 DECL_HANDLER(close_handle
)
550 close_handle( current
->process
, req
->handle
, &reply
->fd
);
553 /* set a handle information */
554 DECL_HANDLER(set_handle_info
)
556 reply
->old_flags
= set_handle_flags( current
->process
, req
->handle
, req
->mask
, req
->flags
);
559 /* duplicate a handle */
560 DECL_HANDLER(dup_handle
)
562 struct process
*src
, *dst
;
566 if ((src
= get_process_from_handle( req
->src_process
, PROCESS_DUP_HANDLE
)))
568 if (req
->options
& DUP_HANDLE_MAKE_GLOBAL
)
570 reply
->handle
= duplicate_handle( src
, req
->src_handle
, NULL
,
571 req
->access
, req
->attributes
, req
->options
);
573 else if ((dst
= get_process_from_handle( req
->dst_process
, PROCESS_DUP_HANDLE
)))
575 reply
->handle
= duplicate_handle( src
, req
->src_handle
, dst
,
576 req
->access
, req
->attributes
, req
->options
);
577 release_object( dst
);
579 /* close the handle no matter what happened */
580 if (req
->options
& DUP_HANDLE_CLOSE_SOURCE
)
582 if (src
== current
->process
) close_handle( src
, req
->src_handle
, &reply
->fd
);
583 else close_handle( src
, req
->src_handle
, NULL
);
585 release_object( src
);