2 Unix SMB/Netbios implementation.
4 Files[] structure handling
5 Copyright (C) Andrew Tridgell 1998
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 extern int DEBUGLEVEL;
26 static int real_max_open_files;
28 #define VALID_FNUM(fnum) (((fnum) >= 0) && ((fnum) < real_max_open_files))
30 #define FILE_HANDLE_OFFSET 0x1000
32 static struct bitmap *file_bmap;
34 static files_struct *Files;
36 /* a fsp to use when chaining */
37 static files_struct *chain_fsp = NULL;
38 /* a fsp to use to save when breaking an oplock. */
39 static files_struct *oplock_save_chain_fsp = NULL;
42 * Indirection for file fd's. Needed as POSIX locking
43 * is based on file/process, not fd/process.
45 static file_fd_struct *FileFd;
47 static int files_used, fd_ptr_used;
49 /****************************************************************************
50 find first available file slot
51 ****************************************************************************/
52 files_struct *file_new(void )
55 static int first_file;
56 files_struct *fsp, *next;
58 /* we want to give out file handles differently on each new
59 connection because of a common bug in MS clients where they try to
60 reuse a file descriptor from an earlier smb connection. This code
61 increases the chance that the errant client will get an error rather
62 than causing corruption */
63 if (first_file == 0) {
64 first_file = (getpid() ^ (int)time(NULL)) % real_max_open_files;
67 i = bitmap_find(file_bmap, first_file);
70 * Before we give up, go through the open files
71 * and see if there are any files opened with a
72 * batch oplock. If so break the oplock and then
73 * re-use that entry (if it becomes closed).
74 * This may help as NT/95 clients tend to keep
75 * files batch oplocked for quite a long time
76 * after they have finished with them.
78 for (fsp=Files;fsp;fsp=next) {
80 if (attempt_close_oplocked_file(fsp)) {
85 DEBUG(0,("ERROR! Out of file structures\n"));
89 fsp = (files_struct *)malloc(sizeof(*fsp));
90 if (!fsp) return NULL;
94 first_file = (i+1) % real_max_open_files;
96 bitmap_set(file_bmap, i);
99 fsp->fnum = i + FILE_HANDLE_OFFSET;
100 string_init(&fsp->fsp_name,"");
102 DLIST_ADD(Files, fsp);
104 DEBUG(5,("allocated file structure %d, fnum = %d (%d used)\n",
105 i, fsp->fnum, files_used));
114 /****************************************************************************
115 fd support routines - attempt to find an already open file by dev
116 and inode - increments the ref_count of the returned file_fd_struct *.
117 ****************************************************************************/
118 file_fd_struct *fd_get_already_open(SMB_STRUCT_STAT *sbuf)
120 file_fd_struct *fd_ptr;
122 if(!sbuf) return NULL;
124 for (fd_ptr=FileFd;fd_ptr;fd_ptr=fd_ptr->next) {
125 if ((fd_ptr->ref_count > 0) &&
126 (sbuf->st_dev == fd_ptr->dev) &&
127 (sbuf->st_ino == fd_ptr->inode)) {
130 DEBUG(3,("Re-used file_fd_struct dev = %x, inode = %.0f, ref_count = %d\n",
131 (unsigned int)fd_ptr->dev, (double)fd_ptr->inode,
143 /****************************************************************************
144 fd support routines - attempt to find a empty slot in the FileFd array.
145 Increments the ref_count of the returned entry.
146 ****************************************************************************/
147 file_fd_struct *fd_get_new(void)
149 extern struct current_user current_user;
150 file_fd_struct *fd_ptr;
152 fd_ptr = (file_fd_struct *)malloc(sizeof(*fd_ptr));
154 DEBUG(0,("ERROR! malloc fail for file_fd struct.\n"));
158 ZERO_STRUCTP(fd_ptr);
160 fd_ptr->dev = (SMB_DEV_T)-1;
161 fd_ptr->inode = (SMB_INO_T)-1;
163 fd_ptr->fd_readonly = -1;
164 fd_ptr->fd_writeonly = -1;
165 fd_ptr->real_open_flags = -1;
166 fd_add_to_uid_cache(fd_ptr, (uid_t)current_user.uid);
171 DLIST_ADD(FileFd, fd_ptr);
173 DEBUG(5,("allocated fd_ptr structure (%d used)\n", fd_ptr_used));
179 /****************************************************************************
180 close all open files for a connection
181 ****************************************************************************/
182 void file_close_conn(connection_struct *conn)
184 files_struct *fsp, *next;
186 for (fsp=Files;fsp;fsp=next) {
188 if (fsp->conn == conn && fsp->open) {
189 close_file(fsp,False);
194 /****************************************************************************
195 initialise file structures
196 ****************************************************************************/
198 #define MAX_OPEN_FUDGEFACTOR 10
202 int request_max_open_files = lp_max_open_files();
206 * Set the max_open files to be the requested
207 * max plus a fudgefactor to allow for the extra
208 * fd's we need such as log files etc...
210 real_lim = set_maxfiles(request_max_open_files + MAX_OPEN_FUDGEFACTOR);
212 real_max_open_files = real_lim - MAX_OPEN_FUDGEFACTOR;
214 if(real_max_open_files != request_max_open_files) {
215 DEBUG(1,("file_init: Information only: requested %d \
216 open files, %d are available.\n", request_max_open_files, real_max_open_files));
219 file_bmap = bitmap_allocate(real_max_open_files);
222 exit_server("out of memory in file_init");
226 * Ensure that pipe_handle_oppset is set correctly.
228 set_pipe_handle_offset(real_max_open_files);
232 /****************************************************************************
233 close files open by a specified vuid
234 ****************************************************************************/
235 void file_close_user(int vuid)
237 files_struct *fsp, *next;
239 for (fsp=Files;fsp;fsp=next) {
241 if ((fsp->vuid == vuid) && fsp->open) {
242 close_file(fsp,False);
248 /****************************************************************************
249 Find a fsp given a device, inode and timevalue
250 If this is from a kernel oplock break request then tval may be NULL.
251 ****************************************************************************/
253 files_struct *file_find_dit(SMB_DEV_T dev, SMB_INO_T inode, struct timeval *tval)
258 for (fsp=Files;fsp;fsp=fsp->next,count++) {
260 fsp->fd_ptr != NULL &&
261 fsp->fd_ptr->dev == dev &&
262 fsp->fd_ptr->inode == inode &&
263 (tval ? (fsp->open_time.tv_sec == tval->tv_sec) : True ) &&
264 (tval ? (fsp->open_time.tv_usec == tval->tv_usec) : True )) {
266 DLIST_PROMOTE(Files, fsp);
275 /****************************************************************************
276 Find the first fsp given a device and inode.
277 ****************************************************************************/
279 files_struct *file_find_di_first(SMB_DEV_T dev, SMB_INO_T inode)
283 for (fsp=Files;fsp;fsp=fsp->next) {
285 fsp->fd_ptr != NULL &&
286 fsp->fd_ptr->dev == dev &&
287 fsp->fd_ptr->inode == inode )
294 /****************************************************************************
295 Find the next fsp having the same device and inode.
296 ****************************************************************************/
298 files_struct *file_find_di_next(files_struct *start_fsp)
302 for (fsp = start_fsp->next;fsp;fsp=fsp->next) {
304 fsp->fd_ptr != NULL &&
305 fsp->fd_ptr->dev == start_fsp->fd_ptr->dev &&
306 fsp->fd_ptr->inode == start_fsp->fd_ptr->inode )
313 /****************************************************************************
314 find a fsp that is open for printing
315 ****************************************************************************/
316 files_struct *file_find_print(void)
320 for (fsp=Files;fsp;fsp=fsp->next) {
321 if (fsp->open && fsp->print_file) return fsp;
328 /****************************************************************************
329 sync open files on a connection
330 ****************************************************************************/
331 void file_sync_all(connection_struct *conn)
333 files_struct *fsp, *next;
335 for (fsp=Files;fsp;fsp=next) {
337 if (fsp->open && (conn == fsp->conn) && (fsp->fd_ptr != NULL)) {
344 /****************************************************************************
346 ****************************************************************************/
347 void fd_ptr_free(file_fd_struct *fd_ptr)
349 DLIST_REMOVE(FileFd, fd_ptr);
353 DEBUG(5,("freed fd_ptr structure (%d used)\n", fd_ptr_used));
356 ZERO_STRUCTP(fd_ptr);
362 /****************************************************************************
364 ****************************************************************************/
365 void file_free(files_struct *fsp)
367 DLIST_REMOVE(Files, fsp);
369 string_free(&fsp->fsp_name);
371 if ((fsp->fd_ptr != NULL) && fsp->fd_ptr->ref_count == 0) {
372 fd_ptr_free(fsp->fd_ptr);
375 bitmap_clear(file_bmap, fsp->fnum - FILE_HANDLE_OFFSET);
378 DEBUG(5,("freed files structure %d (%d used)\n",
379 fsp->fnum, files_used));
381 /* this is paranoia, just in case someone tries to reuse the
385 if (fsp == chain_fsp) chain_fsp = NULL;
391 /****************************************************************************
392 get a fsp from a packet given the offset of a 16 bit fnum
393 ****************************************************************************/
394 files_struct *file_fsp(char *buf, int where)
399 if (chain_fsp) return chain_fsp;
401 fnum = SVAL(buf, where);
403 for (fsp=Files;fsp;fsp=fsp->next, count++) {
404 if (fsp->fnum == fnum) {
407 DLIST_PROMOTE(Files, fsp);
415 /****************************************************************************
416 Reset the chained fsp - done at the start of a packet reply
417 ****************************************************************************/
419 void file_chain_reset(void)
424 /****************************************************************************
425 Save the chained fsp - done when about to do an oplock break.
426 ****************************************************************************/
428 void file_chain_save(void)
430 oplock_save_chain_fsp = chain_fsp;
433 /****************************************************************************
434 Restore the chained fsp - done after an oplock break.
435 ****************************************************************************/
436 void file_chain_restore(void)
438 chain_fsp = oplock_save_chain_fsp;