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 access
&= ~RESERVED_ALL
;
225 if (inherit
) access
|= RESERVED_INHERIT
;
226 if (!process
->handles
)
228 set_error( STATUS_NO_MEMORY
);
231 return alloc_entry( process
->handles
, obj
, access
);
234 /* allocate a global handle for an object, incrementing its refcount */
235 /* return the handle, or 0 on error */
236 static obj_handle_t
alloc_global_handle( void *obj
, unsigned int access
)
240 if (!(global_table
= (struct handle_table
*)alloc_handle_table( NULL
, 0 )))
243 return handle_local_to_global( alloc_entry( global_table
, obj
, access
));
246 /* return a handle entry, or NULL if the handle is invalid */
247 static struct handle_entry
*get_handle( struct process
*process
, obj_handle_t handle
)
249 struct handle_table
*table
= process
->handles
;
250 struct handle_entry
*entry
;
253 if (handle_is_global(handle
))
255 handle
= handle_global_to_local(handle
);
256 table
= global_table
;
258 if (!table
) goto error
;
259 index
= handle_to_index( handle
);
260 if (index
< 0) goto error
;
261 if (index
> table
->last
) goto error
;
262 entry
= table
->entries
+ index
;
263 if (!entry
->ptr
) goto error
;
267 set_error( STATUS_INVALID_HANDLE
);
271 /* attempt to shrink a table */
272 static void shrink_handle_table( struct handle_table
*table
)
274 struct handle_entry
*entry
= table
->entries
+ table
->last
;
275 struct handle_entry
*new_entries
;
276 int count
= table
->count
;
278 while (table
->last
>= 0)
280 if (entry
->ptr
) break;
284 if (table
->last
>= count
/ 4) return; /* no need to shrink */
285 if (count
< MIN_HANDLE_ENTRIES
* 2) return; /* too small to shrink */
287 if (!(new_entries
= realloc( table
->entries
, count
* sizeof(*new_entries
) ))) return;
288 table
->count
= count
;
289 table
->entries
= new_entries
;
292 /* copy the handle table of the parent process */
293 /* return 1 if OK, 0 on error */
294 struct handle_table
*copy_handle_table( struct process
*process
, struct process
*parent
)
296 struct handle_table
*parent_table
= parent
->handles
;
297 struct handle_table
*table
;
300 assert( parent_table
);
301 assert( parent_table
->obj
.ops
== &handle_table_ops
);
303 if (!(table
= (struct handle_table
*)alloc_handle_table( process
, parent_table
->count
)))
306 if ((table
->last
= parent_table
->last
) >= 0)
308 struct handle_entry
*ptr
= table
->entries
;
309 memcpy( ptr
, parent_table
->entries
, (table
->last
+ 1) * sizeof(struct handle_entry
) );
310 for (i
= 0; i
<= table
->last
; i
++, ptr
++)
312 if (!ptr
->ptr
) continue;
314 if (ptr
->access
& RESERVED_INHERIT
) grab_object( ptr
->ptr
);
315 else ptr
->ptr
= NULL
; /* don't inherit this entry */
318 /* attempt to shrink the table */
319 shrink_handle_table( table
);
323 /* close a handle and decrement the refcount of the associated object */
324 /* return 1 if OK, 0 on error */
325 int close_handle( struct process
*process
, obj_handle_t handle
, int *fd
)
327 struct handle_table
*table
;
328 struct handle_entry
*entry
;
331 if (!(entry
= get_handle( process
, handle
))) return 0;
332 if (entry
->access
& RESERVED_CLOSE_PROTECT
)
334 set_error( STATUS_HANDLE_NOT_CLOSABLE
);
338 if (!obj
->ops
->close_handle( obj
, process
, handle
))
340 set_error( STATUS_HANDLE_NOT_CLOSABLE
);
344 if (fd
) *fd
= entry
->fd
;
345 else if (entry
->fd
!= -1) return 1; /* silently ignore close attempt if we cannot close the fd */
347 table
= handle_is_global(handle
) ? global_table
: process
->handles
;
348 if (entry
< table
->entries
+ table
->free
) table
->free
= entry
- table
->entries
;
349 if (entry
== table
->entries
+ table
->last
) shrink_handle_table( table
);
350 release_object( obj
);
354 /* close all the global handles */
355 void close_global_handles(void)
359 release_object( global_table
);
364 /* retrieve the object corresponding to one of the magic pseudo-handles */
365 static inline struct object
*get_magic_handle( obj_handle_t handle
)
367 switch((unsigned long)handle
)
369 case 0xfffffffe: /* current thread pseudo-handle */
370 return ¤t
->obj
;
371 case 0x7fffffff: /* current process pseudo-handle */
372 case 0xffffffff: /* current process pseudo-handle */
373 return (struct object
*)current
->process
;
379 /* retrieve the object corresponding to a handle, incrementing its refcount */
380 struct object
*get_handle_obj( struct process
*process
, obj_handle_t handle
,
381 unsigned int access
, const struct object_ops
*ops
)
383 struct handle_entry
*entry
;
386 if (!(obj
= get_magic_handle( handle
)))
388 if (!(entry
= get_handle( process
, handle
))) return NULL
;
389 if ((entry
->access
& access
) != access
)
391 set_error( STATUS_ACCESS_DENIED
);
396 if (ops
&& (obj
->ops
!= ops
))
398 set_error( STATUS_OBJECT_TYPE_MISMATCH
); /* not the right type */
401 return grab_object( obj
);
404 /* retrieve the access rights of a given handle */
405 unsigned int get_handle_access( struct process
*process
, obj_handle_t handle
)
407 struct handle_entry
*entry
;
409 if (get_magic_handle( handle
)) return ~0U; /* magic handles have all access rights */
410 if (!(entry
= get_handle( process
, handle
))) return 0;
411 return entry
->access
;
414 /* retrieve the cached fd for a given handle */
415 int get_handle_unix_fd( struct process
*process
, obj_handle_t handle
, unsigned int access
)
417 struct handle_entry
*entry
;
419 if (!(entry
= get_handle( process
, handle
))) return -1;
420 if ((entry
->access
& access
) != access
)
422 set_error( STATUS_ACCESS_DENIED
);
428 /* set the cached fd for a handle if not set already, and return the current value */
429 int set_handle_unix_fd( struct process
*process
, obj_handle_t handle
, int fd
)
431 struct handle_entry
*entry
;
433 if (handle_is_global( handle
)) return -1; /* no fd cache for global handles */
434 if (!(entry
= get_handle( process
, handle
))) return -1;
435 /* if no current fd set it, otherwise return current fd */
436 if (entry
->fd
== -1) entry
->fd
= fd
;
440 /* remove the cached fd and return it */
441 int flush_cached_fd( struct process
*process
, obj_handle_t handle
)
443 struct handle_entry
*entry
= get_handle( process
, handle
);
454 /* find the first inherited handle of the given type */
455 /* this is needed for window stations and desktops (don't ask...) */
456 obj_handle_t
find_inherited_handle( struct process
*process
, const struct object_ops
*ops
)
458 struct handle_table
*table
= process
->handles
;
459 struct handle_entry
*ptr
;
462 if (!table
) return 0;
464 for (i
= 0, ptr
= table
->entries
; i
<= table
->last
; i
++, ptr
++)
466 if (!ptr
->ptr
) continue;
467 if (ptr
->ptr
->ops
!= ops
) continue;
468 if (ptr
->access
& RESERVED_INHERIT
) return index_to_handle(i
);
473 /* get/set the handle reserved flags */
474 /* return the old flags (or -1 on error) */
475 static int set_handle_flags( struct process
*process
, obj_handle_t handle
, int mask
, int flags
)
477 struct handle_entry
*entry
;
478 unsigned int old_access
;
480 if (get_magic_handle( handle
))
482 /* we can retrieve but not set info for magic handles */
483 if (mask
) set_error( STATUS_ACCESS_DENIED
);
486 if (!(entry
= get_handle( process
, handle
))) return -1;
487 old_access
= entry
->access
;
488 mask
= (mask
<< RESERVED_SHIFT
) & RESERVED_ALL
;
489 flags
= (flags
<< RESERVED_SHIFT
) & mask
;
490 entry
->access
= (entry
->access
& ~mask
) | flags
;
491 return (old_access
& RESERVED_ALL
) >> RESERVED_SHIFT
;
494 /* duplicate a handle */
495 obj_handle_t
duplicate_handle( struct process
*src
, obj_handle_t src_handle
, struct process
*dst
,
496 unsigned int access
, int inherit
, int options
)
499 struct object
*obj
= get_handle_obj( src
, src_handle
, 0, NULL
);
502 if (options
& DUP_HANDLE_SAME_ACCESS
)
504 struct handle_entry
*entry
= get_handle( src
, src_handle
);
506 access
= entry
->access
;
507 else /* pseudo-handle, give it full access */
509 access
= STANDARD_RIGHTS_ALL
| SPECIFIC_RIGHTS_ALL
;
513 access
&= ~RESERVED_ALL
;
514 if (options
& DUP_HANDLE_MAKE_GLOBAL
)
515 res
= alloc_global_handle( obj
, access
);
517 res
= alloc_handle( dst
, obj
, access
, inherit
);
518 release_object( obj
);
522 /* open a new handle to an existing object */
523 obj_handle_t
open_object( const struct namespace *namespace, const WCHAR
*name
, size_t len
,
524 const struct object_ops
*ops
, unsigned int access
, int inherit
)
526 obj_handle_t handle
= 0;
527 struct object
*obj
= find_object( namespace, name
, len
);
530 if (ops
&& obj
->ops
!= ops
)
531 set_error( STATUS_OBJECT_TYPE_MISMATCH
);
533 handle
= alloc_handle( current
->process
, obj
, access
, inherit
);
534 release_object( obj
);
537 set_error( STATUS_OBJECT_NAME_NOT_FOUND
);
541 /* return the size of the handle table of a given process */
542 unsigned int get_handle_table_count( struct process
*process
)
544 if (!process
->handles
) return 0;
545 return process
->handles
->count
;
549 DECL_HANDLER(close_handle
)
551 close_handle( current
->process
, req
->handle
, &reply
->fd
);
554 /* set a handle information */
555 DECL_HANDLER(set_handle_info
)
557 reply
->old_flags
= set_handle_flags( current
->process
, req
->handle
, req
->mask
, req
->flags
);
560 /* duplicate a handle */
561 DECL_HANDLER(dup_handle
)
563 struct process
*src
, *dst
;
567 if ((src
= get_process_from_handle( req
->src_process
, PROCESS_DUP_HANDLE
)))
569 if (req
->options
& DUP_HANDLE_MAKE_GLOBAL
)
571 reply
->handle
= duplicate_handle( src
, req
->src_handle
, NULL
,
572 req
->access
, req
->inherit
, req
->options
);
574 else if ((dst
= get_process_from_handle( req
->dst_process
, PROCESS_DUP_HANDLE
)))
576 reply
->handle
= duplicate_handle( src
, req
->src_handle
, dst
,
577 req
->access
, req
->inherit
, req
->options
);
578 release_object( dst
);
580 /* close the handle no matter what happened */
581 if (req
->options
& DUP_HANDLE_CLOSE_SOURCE
)
583 if (src
== current
->process
) close_handle( src
, req
->src_handle
, &reply
->fd
);
584 else close_handle( src
, req
->src_handle
, NULL
);
586 release_object( src
);