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"
41 struct object
*ptr
; /* object */
42 unsigned int access
; /* access rights */
43 int fd
; /* file descriptor (in client process) */
48 struct object obj
; /* object header */
49 struct process
*process
; /* process owning this table */
50 int count
; /* number of allocated entries */
51 int last
; /* last used entry */
52 int free
; /* first entry that may be free */
53 struct handle_entry
*entries
; /* handle entries */
56 static struct handle_table
*global_table
;
58 /* reserved handle access rights */
59 #define RESERVED_SHIFT 26
60 #define RESERVED_INHERIT (HANDLE_FLAG_INHERIT << RESERVED_SHIFT)
61 #define RESERVED_CLOSE_PROTECT (HANDLE_FLAG_PROTECT_FROM_CLOSE << RESERVED_SHIFT)
62 #define RESERVED_ALL (RESERVED_INHERIT | RESERVED_CLOSE_PROTECT)
64 #define MIN_HANDLE_ENTRIES 32
67 /* handle to table index conversion */
69 /* handles are a multiple of 4 under NT; handle 0 is not used */
70 inline static obj_handle_t
index_to_handle( int index
)
72 return (obj_handle_t
)((index
+ 1) << 2);
74 inline static int handle_to_index( obj_handle_t handle
)
76 return ((unsigned int)handle
>> 2) - 1;
79 /* global handle conversion */
81 #define HANDLE_OBFUSCATOR 0x544a4def
83 inline static int handle_is_global( obj_handle_t handle
)
85 return ((unsigned long)handle
^ HANDLE_OBFUSCATOR
) < 0x10000;
87 inline static obj_handle_t
handle_local_to_global( obj_handle_t handle
)
89 if (!handle
) return 0;
90 return (obj_handle_t
)((unsigned long)handle
^ HANDLE_OBFUSCATOR
);
92 inline static obj_handle_t
handle_global_to_local( obj_handle_t handle
)
94 return (obj_handle_t
)((unsigned long)handle
^ HANDLE_OBFUSCATOR
);
98 static void handle_table_dump( struct object
*obj
, int verbose
);
99 static void handle_table_destroy( struct object
*obj
);
101 static const struct object_ops handle_table_ops
=
103 sizeof(struct handle_table
), /* size */
104 handle_table_dump
, /* dump */
105 no_add_queue
, /* add_queue */
106 NULL
, /* remove_queue */
108 NULL
, /* satisfied */
109 no_signal
, /* signal */
110 no_get_fd
, /* get_fd */
111 no_lookup_name
, /* lookup_name */
112 no_close_handle
, /* close_handle */
113 handle_table_destroy
/* destroy */
116 /* dump a handle table */
117 static void handle_table_dump( struct object
*obj
, int verbose
)
120 struct handle_table
*table
= (struct handle_table
*)obj
;
121 struct handle_entry
*entry
= table
->entries
;
123 assert( obj
->ops
== &handle_table_ops
);
125 fprintf( stderr
, "Handle table last=%d count=%d process=%p\n",
126 table
->last
, table
->count
, table
->process
);
127 if (!verbose
) return;
128 entry
= table
->entries
;
129 for (i
= 0; i
<= table
->last
; i
++, entry
++)
131 if (!entry
->ptr
) continue;
132 fprintf( stderr
, " %p: %p %08x ",
133 index_to_handle(i
), entry
->ptr
, entry
->access
);
134 entry
->ptr
->ops
->dump( entry
->ptr
, 0 );
138 /* destroy a handle table */
139 static void handle_table_destroy( struct object
*obj
)
142 struct handle_table
*table
= (struct handle_table
*)obj
;
143 struct handle_entry
*entry
;
145 assert( obj
->ops
== &handle_table_ops
);
147 /* first notify all objects that handles are being closed */
150 for (i
= 0, entry
= table
->entries
; i
<= table
->last
; i
++, entry
++)
152 struct object
*obj
= entry
->ptr
;
153 if (obj
) obj
->ops
->close_handle( obj
, table
->process
, index_to_handle(i
) );
157 for (i
= 0, entry
= table
->entries
; i
<= table
->last
; i
++, entry
++)
159 struct object
*obj
= entry
->ptr
;
161 if (obj
) release_object( obj
);
163 free( table
->entries
);
166 /* allocate a new handle table */
167 struct handle_table
*alloc_handle_table( struct process
*process
, int count
)
169 struct handle_table
*table
;
171 if (count
< MIN_HANDLE_ENTRIES
) count
= MIN_HANDLE_ENTRIES
;
172 if (!(table
= alloc_object( &handle_table_ops
)))
174 table
->process
= process
;
175 table
->count
= count
;
178 if ((table
->entries
= mem_alloc( count
* sizeof(*table
->entries
) ))) return table
;
179 release_object( table
);
183 /* grow a handle table */
184 static int grow_handle_table( struct handle_table
*table
)
186 struct handle_entry
*new_entries
;
187 int count
= table
->count
;
189 if (count
>= INT_MAX
/ 2) return 0;
191 if (!(new_entries
= realloc( table
->entries
, count
* sizeof(struct handle_entry
) )))
193 set_error( STATUS_NO_MEMORY
);
196 table
->entries
= new_entries
;
197 table
->count
= count
;
201 /* allocate the first free entry in the handle table */
202 static obj_handle_t
alloc_entry( struct handle_table
*table
, void *obj
, unsigned int access
)
204 struct handle_entry
*entry
= table
->entries
+ table
->free
;
207 for (i
= table
->free
; i
<= table
->last
; i
++, entry
++) if (!entry
->ptr
) goto found
;
208 if (i
>= table
->count
)
210 if (!grow_handle_table( table
)) return 0;
211 entry
= table
->entries
+ i
; /* the entries may have moved */
216 entry
->ptr
= grab_object( obj
);
217 entry
->access
= access
;
219 return index_to_handle(i
);
222 /* allocate a handle for an object, incrementing its refcount */
223 /* return the handle, or 0 on error */
224 obj_handle_t
alloc_handle( struct process
*process
, void *obj
, unsigned int access
, int inherit
)
226 access
&= ~RESERVED_ALL
;
227 if (inherit
) access
|= RESERVED_INHERIT
;
228 if (!process
->handles
)
230 set_error( STATUS_NO_MEMORY
);
233 return alloc_entry( process
->handles
, obj
, access
);
236 /* allocate a global handle for an object, incrementing its refcount */
237 /* return the handle, or 0 on error */
238 static obj_handle_t
alloc_global_handle( void *obj
, unsigned int access
)
242 if (!(global_table
= (struct handle_table
*)alloc_handle_table( NULL
, 0 )))
245 return handle_local_to_global( alloc_entry( global_table
, obj
, access
));
248 /* return a handle entry, or NULL if the handle is invalid */
249 static struct handle_entry
*get_handle( struct process
*process
, obj_handle_t handle
)
251 struct handle_table
*table
= process
->handles
;
252 struct handle_entry
*entry
;
255 if (handle_is_global(handle
))
257 handle
= handle_global_to_local(handle
);
258 table
= global_table
;
260 if (!table
) goto error
;
261 index
= handle_to_index( handle
);
262 if (index
< 0) goto error
;
263 if (index
> table
->last
) goto error
;
264 entry
= table
->entries
+ index
;
265 if (!entry
->ptr
) goto error
;
269 set_error( STATUS_INVALID_HANDLE
);
273 /* attempt to shrink a table */
274 static void shrink_handle_table( struct handle_table
*table
)
276 struct handle_entry
*entry
= table
->entries
+ table
->last
;
277 struct handle_entry
*new_entries
;
278 int count
= table
->count
;
280 while (table
->last
>= 0)
282 if (entry
->ptr
) break;
286 if (table
->last
>= count
/ 4) return; /* no need to shrink */
287 if (count
< MIN_HANDLE_ENTRIES
* 2) return; /* too small to shrink */
289 if (!(new_entries
= realloc( table
->entries
, count
* sizeof(*new_entries
) ))) return;
290 table
->count
= count
;
291 table
->entries
= new_entries
;
294 /* copy the handle table of the parent process */
295 /* return 1 if OK, 0 on error */
296 struct handle_table
*copy_handle_table( struct process
*process
, struct process
*parent
)
298 struct handle_table
*parent_table
= parent
->handles
;
299 struct handle_table
*table
;
302 assert( parent_table
);
303 assert( parent_table
->obj
.ops
== &handle_table_ops
);
305 if (!(table
= (struct handle_table
*)alloc_handle_table( process
, parent_table
->count
)))
308 if ((table
->last
= parent_table
->last
) >= 0)
310 struct handle_entry
*ptr
= table
->entries
;
311 memcpy( ptr
, parent_table
->entries
, (table
->last
+ 1) * sizeof(struct handle_entry
) );
312 for (i
= 0; i
<= table
->last
; i
++, ptr
++)
314 if (!ptr
->ptr
) continue;
316 if (ptr
->access
& RESERVED_INHERIT
) grab_object( ptr
->ptr
);
317 else ptr
->ptr
= NULL
; /* don't inherit this entry */
320 /* attempt to shrink the table */
321 shrink_handle_table( table
);
325 /* close a handle and decrement the refcount of the associated object */
326 /* return 1 if OK, 0 on error */
327 int close_handle( struct process
*process
, obj_handle_t handle
, int *fd
)
329 struct handle_table
*table
;
330 struct handle_entry
*entry
;
333 if (!(entry
= get_handle( process
, handle
))) return 0;
334 if (entry
->access
& RESERVED_CLOSE_PROTECT
)
336 set_error( STATUS_HANDLE_NOT_CLOSABLE
);
340 if (!obj
->ops
->close_handle( obj
, process
, handle
))
342 set_error( STATUS_HANDLE_NOT_CLOSABLE
);
346 if (fd
) *fd
= entry
->fd
;
347 else if (entry
->fd
!= -1) return 1; /* silently ignore close attempt if we cannot close the fd */
349 table
= handle_is_global(handle
) ? global_table
: process
->handles
;
350 if (entry
< table
->entries
+ table
->free
) table
->free
= entry
- table
->entries
;
351 if (entry
== table
->entries
+ table
->last
) shrink_handle_table( table
);
352 release_object( obj
);
356 /* close all the global handles */
357 void close_global_handles(void)
361 release_object( global_table
);
366 /* retrieve the object corresponding to one of the magic pseudo-handles */
367 static inline struct object
*get_magic_handle( obj_handle_t handle
)
369 switch((unsigned long)handle
)
371 case 0xfffffffe: /* current thread pseudo-handle */
372 return ¤t
->obj
;
373 case 0x7fffffff: /* current process pseudo-handle */
374 case 0xffffffff: /* current process pseudo-handle */
375 return (struct object
*)current
->process
;
381 /* retrieve the object corresponding to a handle, incrementing its refcount */
382 struct object
*get_handle_obj( struct process
*process
, obj_handle_t handle
,
383 unsigned int access
, const struct object_ops
*ops
)
385 struct handle_entry
*entry
;
388 if (!(obj
= get_magic_handle( handle
)))
390 if (!(entry
= get_handle( process
, handle
))) return NULL
;
391 if ((entry
->access
& access
) != access
)
393 set_error( STATUS_ACCESS_DENIED
);
398 if (ops
&& (obj
->ops
!= ops
))
400 set_error( STATUS_OBJECT_TYPE_MISMATCH
); /* not the right type */
403 return grab_object( obj
);
406 /* retrieve the access rights of a given handle */
407 unsigned int get_handle_access( struct process
*process
, obj_handle_t handle
)
409 struct handle_entry
*entry
;
411 if (get_magic_handle( handle
)) return ~0U; /* magic handles have all access rights */
412 if (!(entry
= get_handle( process
, handle
))) return 0;
413 return entry
->access
;
416 /* retrieve the cached fd for a given handle */
417 int get_handle_unix_fd( struct process
*process
, obj_handle_t handle
, unsigned int access
)
419 struct handle_entry
*entry
;
421 if (!(entry
= get_handle( process
, handle
))) return -1;
422 if ((entry
->access
& access
) != access
)
424 set_error( STATUS_ACCESS_DENIED
);
430 /* set the cached fd for a handle if not set already, and return the current value */
431 int set_handle_unix_fd( struct process
*process
, obj_handle_t handle
, int fd
)
433 struct handle_entry
*entry
;
435 if (handle_is_global( handle
)) return -1; /* no fd cache for global handles */
436 if (!(entry
= get_handle( process
, handle
))) return -1;
437 /* if no current fd set it, otherwise return current fd */
438 if (entry
->fd
== -1) entry
->fd
= fd
;
442 /* remove the cached fd and return it */
443 int flush_cached_fd( struct process
*process
, obj_handle_t handle
)
445 struct handle_entry
*entry
= get_handle( process
, handle
);
456 /* find the first inherited handle of the given type */
457 /* this is needed for window stations and desktops (don't ask...) */
458 obj_handle_t
find_inherited_handle( struct process
*process
, const struct object_ops
*ops
)
460 struct handle_table
*table
= process
->handles
;
461 struct handle_entry
*ptr
;
464 if (!table
) return 0;
466 for (i
= 0, ptr
= table
->entries
; i
<= table
->last
; i
++, ptr
++)
468 if (!ptr
->ptr
) continue;
469 if (ptr
->ptr
->ops
!= ops
) continue;
470 if (ptr
->access
& RESERVED_INHERIT
) return index_to_handle(i
);
475 /* get/set the handle reserved flags */
476 /* return the old flags (or -1 on error) */
477 static int set_handle_flags( struct process
*process
, obj_handle_t handle
, int mask
, int flags
)
479 struct handle_entry
*entry
;
480 unsigned int old_access
;
482 if (get_magic_handle( handle
))
484 /* we can retrieve but not set info for magic handles */
485 if (mask
) set_error( STATUS_ACCESS_DENIED
);
488 if (!(entry
= get_handle( process
, handle
))) return -1;
489 old_access
= entry
->access
;
490 mask
= (mask
<< RESERVED_SHIFT
) & RESERVED_ALL
;
491 flags
= (flags
<< RESERVED_SHIFT
) & mask
;
492 entry
->access
= (entry
->access
& ~mask
) | flags
;
493 return (old_access
& RESERVED_ALL
) >> RESERVED_SHIFT
;
496 /* duplicate a handle */
497 obj_handle_t
duplicate_handle( struct process
*src
, obj_handle_t src_handle
, struct process
*dst
,
498 unsigned int access
, int inherit
, int options
)
501 struct object
*obj
= get_handle_obj( src
, src_handle
, 0, NULL
);
504 if (options
& DUP_HANDLE_SAME_ACCESS
)
506 struct handle_entry
*entry
= get_handle( src
, src_handle
);
508 access
= entry
->access
;
509 else /* pseudo-handle, give it full access */
511 access
= STANDARD_RIGHTS_ALL
| SPECIFIC_RIGHTS_ALL
;
515 access
&= ~RESERVED_ALL
;
516 if (options
& DUP_HANDLE_MAKE_GLOBAL
)
517 res
= alloc_global_handle( obj
, access
);
519 res
= alloc_handle( dst
, obj
, access
, inherit
);
520 release_object( obj
);
524 /* open a new handle to an existing object */
525 obj_handle_t
open_object( const struct namespace *namespace, const struct unicode_str
*name
,
526 const struct object_ops
*ops
, unsigned int access
, unsigned int attr
)
528 obj_handle_t handle
= 0;
529 struct object
*obj
= find_object( namespace, name
, attr
);
532 if (ops
&& obj
->ops
!= ops
)
533 set_error( STATUS_OBJECT_TYPE_MISMATCH
);
535 handle
= alloc_handle( current
->process
, obj
, access
, attr
& OBJ_INHERIT
);
536 release_object( obj
);
539 set_error( STATUS_OBJECT_NAME_NOT_FOUND
);
543 /* return the size of the handle table of a given process */
544 unsigned int get_handle_table_count( struct process
*process
)
546 if (!process
->handles
) return 0;
547 return process
->handles
->count
;
551 DECL_HANDLER(close_handle
)
553 close_handle( current
->process
, req
->handle
, &reply
->fd
);
556 /* set a handle information */
557 DECL_HANDLER(set_handle_info
)
559 reply
->old_flags
= set_handle_flags( current
->process
, req
->handle
, req
->mask
, req
->flags
);
562 /* duplicate a handle */
563 DECL_HANDLER(dup_handle
)
565 struct process
*src
, *dst
;
569 if ((src
= get_process_from_handle( req
->src_process
, PROCESS_DUP_HANDLE
)))
571 if (req
->options
& DUP_HANDLE_MAKE_GLOBAL
)
573 reply
->handle
= duplicate_handle( src
, req
->src_handle
, NULL
,
574 req
->access
, req
->inherit
, req
->options
);
576 else if ((dst
= get_process_from_handle( req
->dst_process
, PROCESS_DUP_HANDLE
)))
578 reply
->handle
= duplicate_handle( src
, req
->src_handle
, dst
,
579 req
->access
, req
->inherit
, req
->options
);
580 release_object( dst
);
582 /* close the handle no matter what happened */
583 if (req
->options
& DUP_HANDLE_CLOSE_SOURCE
)
585 if (src
== current
->process
) close_handle( src
, req
->src_handle
, &reply
->fd
);
586 else close_handle( src
, req
->src_handle
, NULL
);
588 release_object( src
);