2 Unix SMB/CIFS implementation.
3 Files[] structure handling
4 Copyright (C) Andrew Tridgell 1998
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program 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
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 static int real_max_open_files
;
25 #define VALID_FNUM(fnum) (((fnum) >= 0) && ((fnum) < real_max_open_files))
27 #define FILE_HANDLE_OFFSET 0x1000
29 static struct bitmap
*file_bmap
;
31 static files_struct
*Files
;
33 /* a fsp to use when chaining */
34 static files_struct
*chain_fsp
= NULL
;
35 /* a fsp to use to save when breaking an oplock. */
36 static files_struct
*oplock_save_chain_fsp
= NULL
;
38 static int files_used
;
40 /****************************************************************************
41 Return a unique number identifying this fsp over the life of this pid.
42 ****************************************************************************/
44 static unsigned long get_gen_count(void)
46 static unsigned long file_gen_counter
;
48 if ((++file_gen_counter
) == 0)
49 return ++file_gen_counter
;
50 return file_gen_counter
;
53 /****************************************************************************
54 Find first available file slot.
55 ****************************************************************************/
57 files_struct
*file_new(connection_struct
*conn
)
60 static int first_file
;
61 files_struct
*fsp
, *next
;
63 /* we want to give out file handles differently on each new
64 connection because of a common bug in MS clients where they try to
65 reuse a file descriptor from an earlier smb connection. This code
66 increases the chance that the errant client will get an error rather
67 than causing corruption */
68 if (first_file
== 0) {
69 first_file
= (sys_getpid() ^ (int)time(NULL
)) % real_max_open_files
;
72 i
= bitmap_find(file_bmap
, first_file
);
75 * Before we give up, go through the open files
76 * and see if there are any files opened with a
77 * batch oplock. If so break the oplock and then
78 * re-use that entry (if it becomes closed).
79 * This may help as NT/95 clients tend to keep
80 * files batch oplocked for quite a long time
81 * after they have finished with them.
83 for (fsp
=Files
;fsp
;fsp
=next
) {
85 if (attempt_close_oplocked_file(fsp
)) {
86 return file_new(conn
);
90 DEBUG(0,("ERROR! Out of file structures\n"));
91 unix_ERR_class
= ERRSRV
;
92 unix_ERR_code
= ERRnofids
;
96 fsp
= (files_struct
*)malloc(sizeof(*fsp
));
98 unix_ERR_class
= ERRSRV
;
99 unix_ERR_code
= ERRnofids
;
106 fsp
->file_id
= get_gen_count();
107 GetTimeOfDay(&fsp
->open_time
);
109 first_file
= (i
+1) % real_max_open_files
;
111 bitmap_set(file_bmap
, i
);
114 fsp
->fnum
= i
+ FILE_HANDLE_OFFSET
;
115 SMB_ASSERT(fsp
->fnum
< 65536);
117 string_set(&fsp
->fsp_name
,"");
119 DLIST_ADD(Files
, fsp
);
121 DEBUG(5,("allocated file structure %d, fnum = %d (%d used)\n",
122 i
, fsp
->fnum
, files_used
));
129 /****************************************************************************
130 Close all open files for a connection.
131 ****************************************************************************/
133 void file_close_conn(connection_struct
*conn
)
135 files_struct
*fsp
, *next
;
137 for (fsp
=Files
;fsp
;fsp
=next
) {
139 if (fsp
->conn
== conn
) {
140 close_file(fsp
,False
);
145 /****************************************************************************
146 Initialise file structures.
147 ****************************************************************************/
149 #define MAX_OPEN_FUDGEFACTOR 20
153 int request_max_open_files
= lp_max_open_files();
157 * Set the max_open files to be the requested
158 * max plus a fudgefactor to allow for the extra
159 * fd's we need such as log files etc...
161 real_lim
= set_maxfiles(request_max_open_files
+ MAX_OPEN_FUDGEFACTOR
);
163 real_max_open_files
= real_lim
- MAX_OPEN_FUDGEFACTOR
;
165 if (real_max_open_files
+ FILE_HANDLE_OFFSET
+ MAX_OPEN_PIPES
> 65536)
166 real_max_open_files
= 65536 - FILE_HANDLE_OFFSET
- MAX_OPEN_PIPES
;
168 if(real_max_open_files
!= request_max_open_files
) {
169 DEBUG(1,("file_init: Information only: requested %d \
170 open files, %d are available.\n", request_max_open_files
, real_max_open_files
));
173 SMB_ASSERT(real_max_open_files
> 100);
175 file_bmap
= bitmap_allocate(real_max_open_files
);
178 exit_server("out of memory in file_init");
182 * Ensure that pipe_handle_oppset is set correctly.
184 set_pipe_handle_offset(real_max_open_files
);
187 /****************************************************************************
188 Close files open by a specified vuid.
189 ****************************************************************************/
191 void file_close_user(int vuid
)
193 files_struct
*fsp
, *next
;
195 for (fsp
=Files
;fsp
;fsp
=next
) {
197 if (fsp
->vuid
== vuid
) {
198 close_file(fsp
,False
);
203 /****************************************************************************
204 Find a fsp given a file descriptor.
205 ****************************************************************************/
207 files_struct
*file_find_fd(int fd
)
212 for (fsp
=Files
;fsp
;fsp
=fsp
->next
,count
++) {
215 DLIST_PROMOTE(Files
, fsp
);
224 /****************************************************************************
225 Find a fsp given a device, inode and file_id.
226 ****************************************************************************/
228 files_struct
*file_find_dif(SMB_DEV_T dev
, SMB_INO_T inode
, unsigned long file_id
)
233 for (fsp
=Files
;fsp
;fsp
=fsp
->next
,count
++) {
236 fsp
->inode
== inode
&&
237 fsp
->file_id
== file_id
) {
239 DLIST_PROMOTE(Files
, fsp
);
248 /****************************************************************************
249 Check if an fsp still exists.
250 ****************************************************************************/
252 files_struct
*file_find_fsp(files_struct
*orig_fsp
)
256 for (fsp
=Files
;fsp
;fsp
=fsp
->next
) {
264 /****************************************************************************
265 Find the first fsp given a device and inode.
266 ****************************************************************************/
268 files_struct
*file_find_di_first(SMB_DEV_T dev
, SMB_INO_T inode
)
272 for (fsp
=Files
;fsp
;fsp
=fsp
->next
) {
273 if ( fsp
->fd
!= -1 &&
275 fsp
->inode
== inode
)
282 /****************************************************************************
283 Find the next fsp having the same device and inode.
284 ****************************************************************************/
286 files_struct
*file_find_di_next(files_struct
*start_fsp
)
290 for (fsp
= start_fsp
->next
;fsp
;fsp
=fsp
->next
) {
291 if ( fsp
->fd
!= -1 &&
292 fsp
->dev
== start_fsp
->dev
&&
293 fsp
->inode
== start_fsp
->inode
)
300 /****************************************************************************
301 Find a fsp that is open for printing.
302 ****************************************************************************/
304 files_struct
*file_find_print(void)
308 for (fsp
=Files
;fsp
;fsp
=fsp
->next
) {
309 if (fsp
->print_file
) return fsp
;
315 /****************************************************************************
316 Sync open files on a connection.
317 ****************************************************************************/
319 void file_sync_all(connection_struct
*conn
)
321 files_struct
*fsp
, *next
;
323 for (fsp
=Files
;fsp
;fsp
=next
) {
325 if ((conn
== fsp
->conn
) && (fsp
->fd
!= -1)) {
331 /****************************************************************************
333 ****************************************************************************/
335 void file_free(files_struct
*fsp
)
337 DLIST_REMOVE(Files
, fsp
);
339 string_free(&fsp
->fsp_name
);
341 bitmap_clear(file_bmap
, fsp
->fnum
- FILE_HANDLE_OFFSET
);
344 DEBUG(5,("freed files structure %d (%d used)\n",
345 fsp
->fnum
, files_used
));
347 /* this is paranoia, just in case someone tries to reuse the
351 if (fsp
== chain_fsp
) chain_fsp
= NULL
;
356 /****************************************************************************
357 Get a fsp from a packet given the offset of a 16 bit fnum.
358 ****************************************************************************/
360 files_struct
*file_fsp(char *buf
, int where
)
368 fnum
= SVAL(buf
, where
);
370 for (fsp
=Files
;fsp
;fsp
=fsp
->next
, count
++) {
371 if (fsp
->fnum
== fnum
) {
374 DLIST_PROMOTE(Files
, fsp
);
382 /****************************************************************************
383 Reset the chained fsp - done at the start of a packet reply.
384 ****************************************************************************/
386 void file_chain_reset(void)
391 /****************************************************************************
392 Save the chained fsp - done when about to do an oplock break.
393 ****************************************************************************/
395 void file_chain_save(void)
397 oplock_save_chain_fsp
= chain_fsp
;
400 /****************************************************************************
401 Restore the chained fsp - done after an oplock break.
402 ****************************************************************************/
404 void file_chain_restore(void)
406 chain_fsp
= oplock_save_chain_fsp
;