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 /* the only restriction is that this must be less than PIPE_HANDLE_OFFSET */
27 #define MAX_FNUMS 4096
29 #define VALID_FNUM(fnum) (((fnum) >= 0) && ((fnum) < MAX_FNUMS))
31 #define FILE_HANDLE_OFFSET 0x1000
33 static struct bitmap *file_bmap;
34 static struct bitmap *fd_bmap;
36 static files_struct *Files;
38 /* a fsp to use when chaining */
39 static files_struct *chain_fsp = NULL;
40 /* a fsp to use to save when breaking an oplock. */
41 static files_struct *oplock_save_chain_fsp = NULL;
44 * Indirection for file fd's. Needed as POSIX locking
45 * is based on file/process, not fd/process.
47 static file_fd_struct *FileFd;
49 static int files_used, fd_ptr_used;
51 /****************************************************************************
52 find first available file slot
53 ****************************************************************************/
54 files_struct *file_new(void )
57 static int first_file;
58 files_struct *fsp, *next;
60 /* we want to give out file handles differently on each new
61 connection because of a common bug in MS clients where they try to
62 reuse a file descriptor from an earlier smb connection. This code
63 increases the chance that the errant client will get an error rather
64 than causing corruption */
65 if (first_file == 0) {
66 first_file = (getpid() ^ (int)time(NULL)) % MAX_FNUMS;
69 i = bitmap_find(file_bmap, first_file);
72 * Before we give up, go through the open files
73 * and see if there are any files opened with a
74 * batch oplock. If so break the oplock and then
75 * re-use that entry (if it becomes closed).
76 * This may help as NT/95 clients tend to keep
77 * files batch oplocked for quite a long time
78 * after they have finished with them.
80 for (fsp=Files;fsp;fsp=next) {
82 if (attempt_close_oplocked_file(fsp)) {
87 DEBUG(0,("ERROR! Out of file structures\n"));
91 fsp = (files_struct *)malloc(sizeof(*fsp));
92 if (!fsp) return NULL;
94 memset(fsp, 0, sizeof(*fsp));
96 first_file = (i+1) % MAX_FNUMS;
98 bitmap_set(file_bmap, i);
101 fsp->fnum = i + FILE_HANDLE_OFFSET;
102 string_init(&fsp->fsp_name,"");
104 DLIST_ADD(Files, fsp);
106 DEBUG(5,("allocated file structure %d (%d used)\n",
116 /****************************************************************************
117 fd support routines - attempt to find an already open file by dev
118 and inode - increments the ref_count of the returned file_fd_struct *.
119 ****************************************************************************/
120 file_fd_struct *fd_get_already_open(struct stat *sbuf)
122 file_fd_struct *fd_ptr;
124 if(!sbuf) return NULL;
126 for (fd_ptr=FileFd;fd_ptr;fd_ptr=fd_ptr->next) {
127 if ((fd_ptr->ref_count > 0) &&
128 (((uint32)sbuf->st_dev) == fd_ptr->dev) &&
129 (((uint32)sbuf->st_ino) == fd_ptr->inode)) {
131 DEBUG(3,("Re-used file_fd_struct dev = %x, inode = %x, ref_count = %d\n",
132 fd_ptr->dev, 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;
151 file_fd_struct *fd_ptr;
153 i = bitmap_find(fd_bmap, 1);
155 DEBUG(0,("ERROR! Out of file_fd structures\n"));
159 fd_ptr = (file_fd_struct *)malloc(sizeof(*fd_ptr));
160 if (!fd_ptr) return NULL;
162 memset(fd_ptr, 0, sizeof(*fd_ptr));
165 fd_ptr->dev = (uint32)-1;
166 fd_ptr->inode = (uint32)-1;
168 fd_ptr->fd_readonly = -1;
169 fd_ptr->fd_writeonly = -1;
170 fd_ptr->real_open_flags = -1;
171 fd_add_to_uid_cache(fd_ptr, (uid_t)current_user.uid);
174 bitmap_set(fd_bmap, i);
177 DLIST_ADD(FileFd, fd_ptr);
179 DEBUG(5,("allocated fd_ptr structure %d (%d used)\n",
186 /****************************************************************************
187 close all open files for a connection
188 ****************************************************************************/
189 void file_close_conn(connection_struct *conn)
191 files_struct *fsp, *next;
193 for (fsp=Files;fsp;fsp=next) {
195 if (fsp->conn == conn && fsp->open) {
196 if (fsp->is_directory)
197 close_directory(fsp);
199 close_file(fsp,False);
204 /****************************************************************************
205 initialise file structures
206 ****************************************************************************/
209 file_bmap = bitmap_allocate(MAX_FNUMS);
210 fd_bmap = bitmap_allocate(MAX_FNUMS);
212 if (!file_bmap || !fd_bmap) {
213 exit_server("out of memory in file_init");
216 #if (defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE))
219 getrlimit(RLIMIT_NOFILE, &rlp);
220 /* Set the fd limit to be MAX_FNUMS + 10 to
221 * account for the extra fd we need
222 * as well as the log files and standard
224 rlp.rlim_cur = (MAX_FNUMS+10>rlp.rlim_max)?
225 rlp.rlim_max:MAX_FNUMS+10;
226 setrlimit(RLIMIT_NOFILE, &rlp);
227 getrlimit(RLIMIT_NOFILE, &rlp);
228 DEBUG(3,("Maximum number of open files per session is %d\n",
235 /****************************************************************************
236 close files open by a specified vuid
237 ****************************************************************************/
238 void file_close_user(int vuid)
240 files_struct *fsp, *next;
242 for (fsp=Files;fsp;fsp=next) {
244 if ((fsp->vuid == vuid) && fsp->open) {
245 if(!fsp->is_directory)
246 close_file(fsp,False);
248 close_directory(fsp);
254 /****************************************************************************
255 find a fsp given a device, inode and timevalue
256 ****************************************************************************/
257 files_struct *file_find_dit(int dev, int inode, struct timeval *tval)
262 for (fsp=Files;fsp;fsp=fsp->next,count++) {
264 fsp->fd_ptr->dev == dev &&
265 fsp->fd_ptr->inode == inode &&
266 fsp->open_time.tv_sec == tval->tv_sec &&
267 fsp->open_time.tv_usec == tval->tv_usec) {
269 DLIST_PROMOTE(Files, fsp);
279 /****************************************************************************
280 find a fsp that is open for printing
281 ****************************************************************************/
282 files_struct *file_find_print(void)
286 for (fsp=Files;fsp;fsp=fsp->next) {
287 if (fsp->open && fsp->print_file) return fsp;
293 /****************************************************************************
294 sync open files on a connection
295 ****************************************************************************/
296 void file_sync_all(connection_struct *conn)
298 files_struct *fsp, *next;
300 for (fsp=Files;fsp;fsp=next) {
302 if (fsp->open && conn == fsp->conn) {
309 /****************************************************************************
311 ****************************************************************************/
312 static void fd_ptr_free(file_fd_struct *fd_ptr)
314 DLIST_REMOVE(FileFd, fd_ptr);
316 bitmap_clear(fd_bmap, fd_ptr->fdnum);
319 DEBUG(5,("freed fd_ptr structure %d (%d used)\n",
320 fd_ptr->fdnum, fd_ptr_used));
323 memset(fd_ptr, 0, sizeof(*fd_ptr));
329 /****************************************************************************
331 ****************************************************************************/
332 void file_free(files_struct *fsp)
334 DLIST_REMOVE(Files, fsp);
336 string_free(&fsp->fsp_name);
338 if (fsp->fd_ptr && fsp->fd_ptr->ref_count == 0) {
339 fd_ptr_free(fsp->fd_ptr);
342 bitmap_clear(file_bmap, fsp->fnum - FILE_HANDLE_OFFSET);
345 DEBUG(5,("freed files structure %d (%d used)\n",
346 fsp->fnum, files_used));
348 /* this is paranoia, just in case someone tries to reuse the
350 memset(fsp, 0, sizeof(*fsp));
352 if (fsp == chain_fsp) chain_fsp = NULL;
358 /****************************************************************************
359 get a fsp from a packet given the offset of a 16 bit fnum
360 ****************************************************************************/
361 files_struct *file_fsp(char *buf, int where)
366 if (chain_fsp) return chain_fsp;
368 fnum = SVAL(buf, where);
370 for (fsp=Files;fsp;fsp=fsp->next, count++) {
371 if (fsp->fnum == fnum) {
374 DLIST_PROMOTE(Files, fsp);
384 /****************************************************************************
385 reset the chained fsp - done at the start of a packet reply
386 ****************************************************************************/
387 void file_chain_reset(void)
392 /****************************************************************************
393 Save the chained fsp - done when about to do an oplock break.
394 ****************************************************************************/
396 void file_chain_save(void)
398 oplock_save_chain_fsp = chain_fsp;
401 /****************************************************************************
402 Restore the chained fsp - done after an oplock break.
403 ****************************************************************************/
404 void file_chain_restore(void)
406 chain_fsp = oplock_save_chain_fsp;