1 /*
2 * VFS module to provide a sorted directory list.
3 *
4 * Copyright (C) Andy Kelk (andy@mopoke.co.uk), 2009
5 *
6 *
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 3 of the License, or
10 * (at your option) any later version.
11 *
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.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include "includes.h"
22 #include "smbd/smbd.h"
23 #include "system/filesys.h"
24
compare_dirent(const struct dirent * da,const struct dirent * db)25 static int compare_dirent (const struct dirent *da, const struct dirent *db)
26 {
27 return strcasecmp_m(da->d_name, db->d_name);
28 }
29
30 struct dirsort_privates {
31 struct dirsort_privates *prev, *next;
32 long pos;
33 struct dirent *directory_list;
34 unsigned int number_of_entries;
35 struct timespec mtime;
36 DIR *source_directory;
37 files_struct *fsp; /* If open via FDOPENDIR. */
38 struct smb_filename *smb_fname; /* If open via OPENDIR */
39 };
40
get_sorted_dir_mtime(vfs_handle_struct * handle,struct dirsort_privates * data,struct timespec * ret_mtime)41 static bool get_sorted_dir_mtime(vfs_handle_struct *handle,
42 struct dirsort_privates *data,
43 struct timespec *ret_mtime)
44 {
45 int ret;
46 struct timespec mtime;
47 NTSTATUS status;
48
49 if (data->fsp) {
50 status = vfs_stat_fsp(data->fsp);
51 if (!NT_STATUS_IS_OK(status)) {
52 return false;
53 }
54 mtime = data->fsp->fsp_name->st.st_ex_mtime;
55 } else {
56 ret = SMB_VFS_STAT(handle->conn, data->smb_fname);
57 if (ret == -1) {
58 return false;
59 }
60 mtime = data->smb_fname->st.st_ex_mtime;
61 }
62
63 *ret_mtime = mtime;
64
65 return true;
66 }
67
open_and_sort_dir(vfs_handle_struct * handle,struct dirsort_privates * data)68 static bool open_and_sort_dir(vfs_handle_struct *handle,
69 struct dirsort_privates *data)
70 {
71 uint32_t total_count = 0;
72 /* This should be enough for most use cases */
73 uint32_t dirent_allocated = 64;
74 struct dirent *dp;
75
76 data->number_of_entries = 0;
77
78 if (get_sorted_dir_mtime(handle, data, &data->mtime) == false) {
79 return false;
80 }
81
82 dp = SMB_VFS_NEXT_READDIR(handle, data->source_directory, NULL);
83 if (dp == NULL) {
84 return false;
85 }
86
87 /* Set up an array and read the directory entries into it */
88 TALLOC_FREE(data->directory_list); /* destroy previous cache if needed */
89 data->directory_list = talloc_zero_array(data,
90 struct dirent,
91 dirent_allocated);
92 if (data->directory_list == NULL) {
93 return false;
94 }
95
96 do {
97 if (total_count >= dirent_allocated) {
98 struct dirent *dlist;
99
100 /*
101 * Be memory friendly.
102 *
103 * We should not double the amount of memory. With a lot
104 * of files we reach easily 50MB, and doubling will
105 * get much bigger just for a few files more.
106 *
107 * For 200k files this means 50 memory reallocations.
108 */
109 dirent_allocated += 4096;
110
111 dlist = talloc_realloc(data,
112 data->directory_list,
113 struct dirent,
114 dirent_allocated);
115 if (dlist == NULL) {
116 break;
117 }
118 data->directory_list = dlist;
119 }
120 data->directory_list[total_count] = *dp;
121
122 total_count++;
123 dp = SMB_VFS_NEXT_READDIR(handle, data->source_directory, NULL);
124 } while (dp != NULL);
125
126 data->number_of_entries = total_count;
127
128 /* Sort the directory entries by name */
129 TYPESAFE_QSORT(data->directory_list, data->number_of_entries, compare_dirent);
130 return true;
131 }
132
dirsort_opendir(vfs_handle_struct * handle,const struct smb_filename * smb_fname,const char * mask,uint32_t attr)133 static DIR *dirsort_opendir(vfs_handle_struct *handle,
134 const struct smb_filename *smb_fname,
135 const char *mask,
136 uint32_t attr)
137 {
138 struct dirsort_privates *list_head = NULL;
139 struct dirsort_privates *data = NULL;
140
141 if (SMB_VFS_HANDLE_TEST_DATA(handle)) {
142 /* Find the list head of all open directories. */
143 SMB_VFS_HANDLE_GET_DATA(handle, list_head, struct dirsort_privates,
144 return NULL);
145 }
146
147 /* set up our private data about this directory */
148 data = talloc_zero(handle->conn, struct dirsort_privates);
149 if (!data) {
150 return NULL;
151 }
152
153 data->smb_fname = cp_smb_filename(data, smb_fname);
154 if (data->smb_fname == NULL) {
155 TALLOC_FREE(data);
156 return NULL;
157 }
158
159 if (ISDOT(data->smb_fname->base_name)) {
160 struct smb_filename *cwd_fname = vfs_GetWd(data, handle->conn);
161 if (cwd_fname == NULL) {
162 TALLOC_FREE(data);
163 return NULL;
164 }
165 TALLOC_FREE(data->smb_fname->base_name);
166 data->smb_fname->base_name = talloc_move(data->smb_fname,
167 &cwd_fname->base_name);
168 TALLOC_FREE(cwd_fname);
169 }
170
171 /* Open the underlying directory and count the number of entries */
172 data->source_directory = SMB_VFS_NEXT_OPENDIR(handle, smb_fname, mask,
173 attr);
174
175 if (data->source_directory == NULL) {
176 TALLOC_FREE(data);
177 return NULL;
178 }
179
180 if (!open_and_sort_dir(handle, data)) {
181 SMB_VFS_NEXT_CLOSEDIR(handle,data->source_directory);
182 TALLOC_FREE(data);
183 return NULL;
184 }
185
186 /* Add to the private list of all open directories. */
187 DLIST_ADD(list_head, data);
188 SMB_VFS_HANDLE_SET_DATA(handle, list_head, NULL,
189 struct dirsort_privates, return NULL);
190
191 return data->source_directory;
192 }
193
dirsort_fdopendir(vfs_handle_struct * handle,files_struct * fsp,const char * mask,uint32_t attr)194 static DIR *dirsort_fdopendir(vfs_handle_struct *handle,
195 files_struct *fsp,
196 const char *mask,
197 uint32_t attr)
198 {
199 struct dirsort_privates *list_head = NULL;
200 struct dirsort_privates *data = NULL;
201
202 if (SMB_VFS_HANDLE_TEST_DATA(handle)) {
203 /* Find the list head of all open directories. */
204 SMB_VFS_HANDLE_GET_DATA(handle, list_head, struct dirsort_privates,
205 return NULL);
206 }
207
208 /* set up our private data about this directory */
209 data = talloc_zero(handle->conn, struct dirsort_privates);
210 if (!data) {
211 return NULL;
212 }
213
214 data->fsp = fsp;
215
216 /* Open the underlying directory and count the number of entries */
217 data->source_directory = SMB_VFS_NEXT_FDOPENDIR(handle, fsp, mask,
218 attr);
219
220 if (data->source_directory == NULL) {
221 TALLOC_FREE(data);
222 return NULL;
223 }
224
225 if (!open_and_sort_dir(handle, data)) {
226 SMB_VFS_NEXT_CLOSEDIR(handle,data->source_directory);
227 TALLOC_FREE(data);
228 /* fd is now closed. */
229 fsp->fh->fd = -1;
230 return NULL;
231 }
232
233 /* Add to the private list of all open directories. */
234 DLIST_ADD(list_head, data);
235 SMB_VFS_HANDLE_SET_DATA(handle, list_head, NULL,
236 struct dirsort_privates, return NULL);
237
238 return data->source_directory;
239 }
240
dirsort_readdir(vfs_handle_struct * handle,DIR * dirp,SMB_STRUCT_STAT * sbuf)241 static struct dirent *dirsort_readdir(vfs_handle_struct *handle,
242 DIR *dirp,
243 SMB_STRUCT_STAT *sbuf)
244 {
245 struct dirsort_privates *data = NULL;
246 struct timespec current_mtime;
247
248 SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates,
249 return NULL);
250
251 while(data && (data->source_directory != dirp)) {
252 data = data->next;
253 }
254 if (data == NULL) {
255 return NULL;
256 }
257
258 if (get_sorted_dir_mtime(handle, data, ¤t_mtime) == false) {
259 return NULL;
260 }
261
262 /* throw away cache and re-read the directory if we've changed */
263 if (timespec_compare(¤t_mtime, &data->mtime)) {
264 SMB_VFS_NEXT_REWINDDIR(handle, data->source_directory);
265 open_and_sort_dir(handle, data);
266 }
267
268 if (data->pos >= data->number_of_entries) {
269 return NULL;
270 }
271
272 return &data->directory_list[data->pos++];
273 }
274
dirsort_seekdir(vfs_handle_struct * handle,DIR * dirp,long offset)275 static void dirsort_seekdir(vfs_handle_struct *handle, DIR *dirp,
276 long offset)
277 {
278 struct timespec current_mtime;
279 struct dirsort_privates *data = NULL;
280
281 SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates, return);
282
283 /* Find the entry holding dirp. */
284 while(data && (data->source_directory != dirp)) {
285 data = data->next;
286 }
287 if (data == NULL) {
288 return;
289 }
290 if (offset >= data->number_of_entries) {
291 return;
292 }
293 data->pos = offset;
294
295 if (get_sorted_dir_mtime(handle, data, ¤t_mtime) == false) {
296 return;
297 }
298
299 if (timespec_compare(¤t_mtime, &data->mtime)) {
300 /* Directory changed. We must re-read the
301 cache and search for the name that was
302 previously stored at the offset being
303 requested, otherwise after the re-sort
304 we will point to the wrong entry. The
305 OS/2 incremental delete code relies on
306 this. */
307 unsigned int i;
308 char *wanted_name = talloc_strdup(handle->conn,
309 data->directory_list[offset].d_name);
310 if (wanted_name == NULL) {
311 return;
312 }
313 SMB_VFS_NEXT_REWINDDIR(handle, data->source_directory);
314 open_and_sort_dir(handle, data);
315 /* Now search for where we were. */
316 data->pos = 0;
317 for (i = 0; i < data->number_of_entries; i++) {
318 if(strcmp(wanted_name, data->directory_list[i].d_name) == 0) {
319 data->pos = i;
320 break;
321 }
322 }
323 TALLOC_FREE(wanted_name);
324 }
325 }
326
dirsort_telldir(vfs_handle_struct * handle,DIR * dirp)327 static long dirsort_telldir(vfs_handle_struct *handle, DIR *dirp)
328 {
329 struct dirsort_privates *data = NULL;
330 SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates,
331 return -1);
332
333 /* Find the entry holding dirp. */
334 while(data && (data->source_directory != dirp)) {
335 data = data->next;
336 }
337 if (data == NULL) {
338 return -1;
339 }
340 return data->pos;
341 }
342
dirsort_rewinddir(vfs_handle_struct * handle,DIR * dirp)343 static void dirsort_rewinddir(vfs_handle_struct *handle, DIR *dirp)
344 {
345 struct dirsort_privates *data = NULL;
346 SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates, return);
347
348 /* Find the entry holding dirp. */
349 while(data && (data->source_directory != dirp)) {
350 data = data->next;
351 }
352 if (data == NULL) {
353 return;
354 }
355 data->pos = 0;
356 }
357
dirsort_closedir(vfs_handle_struct * handle,DIR * dirp)358 static int dirsort_closedir(vfs_handle_struct *handle, DIR *dirp)
359 {
360 struct dirsort_privates *list_head = NULL;
361 struct dirsort_privates *data = NULL;
362 int ret;
363
364 SMB_VFS_HANDLE_GET_DATA(handle, list_head, struct dirsort_privates, return -1);
365 /* Find the entry holding dirp. */
366 for(data = list_head; data && (data->source_directory != dirp); data = data->next) {
367 ;
368 }
369 if (data == NULL) {
370 return -1;
371 }
372 /* Remove from the list and re-store the list head. */
373 DLIST_REMOVE(list_head, data);
374 SMB_VFS_HANDLE_SET_DATA(handle, list_head, NULL,
375 struct dirsort_privates, return -1);
376
377 ret = SMB_VFS_NEXT_CLOSEDIR(handle, dirp);
378 TALLOC_FREE(data);
379 return ret;
380 }
381
382 static struct vfs_fn_pointers vfs_dirsort_fns = {
383 .opendir_fn = dirsort_opendir,
384 .fdopendir_fn = dirsort_fdopendir,
385 .readdir_fn = dirsort_readdir,
386 .seekdir_fn = dirsort_seekdir,
387 .telldir_fn = dirsort_telldir,
388 .rewind_dir_fn = dirsort_rewinddir,
389 .closedir_fn = dirsort_closedir,
390 };
391
392 static_decl_vfs;
vfs_dirsort_init(TALLOC_CTX * ctx)393 NTSTATUS vfs_dirsort_init(TALLOC_CTX *ctx)
394 {
395 return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "dirsort",
396 &vfs_dirsort_fns);
397 }
398