1 /*
2 * dblist.c -- directory block list functions
3 *
4 * Copyright 1997 by Theodore Ts'o
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
9 * %End-Header%
10 */
11
12 #include <stdio.h>
13 #if HAVE_UNISTD_H
14 #include <unistd.h>
15 #endif
16 #include <string.h>
17 #include <time.h>
18
19 #include "ext2_fs.h"
20 #include "ext2fsP.h"
21
22 static EXT2_QSORT_TYPE dir_block_cmp(const void *a, const void *b);
23 static EXT2_QSORT_TYPE dir_block_cmp2(const void *a, const void *b);
24 static EXT2_QSORT_TYPE (*sortfunc32)(const void *a, const void *b);
25
26 /*
27 * Returns the number of directories in the filesystem as reported by
28 * the group descriptors. Of course, the group descriptors could be
29 * wrong!
30 */
ext2fs_get_num_dirs(ext2_filsys fs,ext2_ino_t * ret_num_dirs)31 errcode_t ext2fs_get_num_dirs(ext2_filsys fs, ext2_ino_t *ret_num_dirs)
32 {
33 dgrp_t i;
34 ext2_ino_t num_dirs, max_dirs;
35
36 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
37
38 num_dirs = 0;
39 max_dirs = fs->super->s_inodes_per_group;
40 for (i = 0; i < fs->group_desc_count; i++) {
41 if (ext2fs_bg_used_dirs_count(fs, i) > max_dirs)
42 num_dirs += max_dirs / 8;
43 else
44 num_dirs += ext2fs_bg_used_dirs_count(fs, i);
45 }
46 if (num_dirs > fs->super->s_inodes_count)
47 num_dirs = fs->super->s_inodes_count;
48
49 *ret_num_dirs = num_dirs;
50
51 return 0;
52 }
53
54 /*
55 * helper function for making a new directory block list (for
56 * initialize and copy).
57 */
make_dblist(ext2_filsys fs,ext2_ino_t size,ext2_ino_t count,struct ext2_db_entry2 * list,ext2_dblist * ret_dblist)58 static errcode_t make_dblist(ext2_filsys fs, ext2_ino_t size,
59 ext2_ino_t count,
60 struct ext2_db_entry2 *list,
61 ext2_dblist *ret_dblist)
62 {
63 ext2_dblist dblist = NULL;
64 errcode_t retval;
65 ext2_ino_t num_dirs;
66 size_t len;
67
68 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
69
70 if ((ret_dblist == 0) && fs->dblist &&
71 (fs->dblist->magic == EXT2_ET_MAGIC_DBLIST))
72 return 0;
73
74 retval = ext2fs_get_mem(sizeof(struct ext2_struct_dblist), &dblist);
75 if (retval)
76 goto cleanup;
77 memset(dblist, 0, sizeof(struct ext2_struct_dblist));
78
79 dblist->magic = EXT2_ET_MAGIC_DBLIST;
80 dblist->fs = fs;
81 if (size)
82 dblist->size = size;
83 else {
84 retval = ext2fs_get_num_dirs(fs, &num_dirs);
85 if (retval)
86 goto cleanup;
87 dblist->size = (num_dirs * 2) + 12;
88 }
89 len = (size_t) sizeof(struct ext2_db_entry2) * dblist->size;
90 dblist->count = count;
91 retval = ext2fs_get_array(dblist->size, sizeof(struct ext2_db_entry2),
92 &dblist->list);
93 if (retval)
94 goto cleanup;
95
96 if (list)
97 memcpy(dblist->list, list, len);
98 else
99 memset(dblist->list, 0, len);
100 if (ret_dblist)
101 *ret_dblist = dblist;
102 else
103 fs->dblist = dblist;
104 return 0;
105 cleanup:
106 if (dblist)
107 ext2fs_free_mem(&dblist);
108 return retval;
109 }
110
111 /*
112 * Initialize a directory block list
113 */
ext2fs_init_dblist(ext2_filsys fs,ext2_dblist * ret_dblist)114 errcode_t ext2fs_init_dblist(ext2_filsys fs, ext2_dblist *ret_dblist)
115 {
116 ext2_dblist dblist;
117 errcode_t retval;
118
119 retval = make_dblist(fs, 0, 0, 0, &dblist);
120 if (retval)
121 return retval;
122
123 dblist->sorted = 1;
124 if (ret_dblist)
125 *ret_dblist = dblist;
126 else
127 fs->dblist = dblist;
128
129 return 0;
130 }
131
132 /*
133 * Copy a directory block list
134 */
ext2fs_copy_dblist(ext2_dblist src,ext2_dblist * dest)135 errcode_t ext2fs_copy_dblist(ext2_dblist src, ext2_dblist *dest)
136 {
137 ext2_dblist dblist;
138 errcode_t retval;
139
140 retval = make_dblist(src->fs, src->size, src->count, src->list,
141 &dblist);
142 if (retval)
143 return retval;
144 dblist->sorted = src->sorted;
145 *dest = dblist;
146 return 0;
147 }
148
149 /*
150 * Close a directory block list
151 *
152 * (moved to closefs.c)
153 */
154
155
156 /*
157 * Add a directory block to the directory block list
158 */
ext2fs_add_dir_block2(ext2_dblist dblist,ext2_ino_t ino,blk64_t blk,e2_blkcnt_t blockcnt)159 errcode_t ext2fs_add_dir_block2(ext2_dblist dblist, ext2_ino_t ino,
160 blk64_t blk, e2_blkcnt_t blockcnt)
161 {
162 struct ext2_db_entry2 *new_entry;
163 errcode_t retval;
164 unsigned long old_size;
165
166 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);
167
168 if (dblist->count >= dblist->size) {
169 old_size = dblist->size * sizeof(struct ext2_db_entry2);
170 dblist->size += dblist->size > 200 ? dblist->size / 2 : 100;
171 retval = ext2fs_resize_mem(old_size, (size_t) dblist->size *
172 sizeof(struct ext2_db_entry2),
173 &dblist->list);
174 if (retval) {
175 dblist->size = old_size / sizeof(struct ext2_db_entry2);
176 return retval;
177 }
178 }
179 new_entry = dblist->list + ( dblist->count++);
180 new_entry->blk = blk;
181 new_entry->ino = ino;
182 new_entry->blockcnt = blockcnt;
183
184 dblist->sorted = 0;
185
186 return 0;
187 }
188
189 /*
190 * Change the directory block to the directory block list
191 */
ext2fs_set_dir_block2(ext2_dblist dblist,ext2_ino_t ino,blk64_t blk,e2_blkcnt_t blockcnt)192 errcode_t ext2fs_set_dir_block2(ext2_dblist dblist, ext2_ino_t ino,
193 blk64_t blk, e2_blkcnt_t blockcnt)
194 {
195 dgrp_t i;
196
197 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);
198
199 for (i=0; i < dblist->count; i++) {
200 if ((dblist->list[i].ino != ino) ||
201 (dblist->list[i].blockcnt != blockcnt))
202 continue;
203 dblist->list[i].blk = blk;
204 dblist->sorted = 0;
205 return 0;
206 }
207 return EXT2_ET_DB_NOT_FOUND;
208 }
209
ext2fs_dblist_sort2(ext2_dblist dblist,EXT2_QSORT_TYPE (* sortfunc)(const void *,const void *))210 void ext2fs_dblist_sort2(ext2_dblist dblist,
211 EXT2_QSORT_TYPE (*sortfunc)(const void *,
212 const void *))
213 {
214 if (!sortfunc)
215 sortfunc = dir_block_cmp2;
216 qsort(dblist->list, (size_t) dblist->count,
217 sizeof(struct ext2_db_entry2), sortfunc);
218 dblist->sorted = 1;
219 }
220
221 /*
222 * This function iterates over the directory block list
223 */
ext2fs_dblist_iterate2(ext2_dblist dblist,int (* func)(ext2_filsys fs,struct ext2_db_entry2 * db_info,void * priv_data),void * priv_data)224 errcode_t ext2fs_dblist_iterate2(ext2_dblist dblist,
225 int (*func)(ext2_filsys fs,
226 struct ext2_db_entry2 *db_info,
227 void *priv_data),
228 void *priv_data)
229 {
230 unsigned long long i;
231 int ret;
232
233 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);
234
235 if (!dblist->sorted)
236 ext2fs_dblist_sort2(dblist, 0);
237 for (i=0; i < dblist->count; i++) {
238 ret = (*func)(dblist->fs, &dblist->list[i], priv_data);
239 if (ret & DBLIST_ABORT)
240 return 0;
241 }
242 return 0;
243 }
244
dir_block_cmp2(const void * a,const void * b)245 static EXT2_QSORT_TYPE dir_block_cmp2(const void *a, const void *b)
246 {
247 const struct ext2_db_entry2 *db_a =
248 (const struct ext2_db_entry2 *) a;
249 const struct ext2_db_entry2 *db_b =
250 (const struct ext2_db_entry2 *) b;
251
252 if (db_a->blk != db_b->blk)
253 return (int) (db_a->blk - db_b->blk);
254
255 if (db_a->ino != db_b->ino)
256 return (int) (db_a->ino - db_b->ino);
257
258 return (db_a->blockcnt - db_b->blockcnt);
259 }
260
ext2fs_dblist_count2(ext2_dblist dblist)261 blk64_t ext2fs_dblist_count2(ext2_dblist dblist)
262 {
263 return dblist->count;
264 }
265
ext2fs_dblist_get_last2(ext2_dblist dblist,struct ext2_db_entry2 ** entry)266 errcode_t ext2fs_dblist_get_last2(ext2_dblist dblist,
267 struct ext2_db_entry2 **entry)
268 {
269 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);
270
271 if (dblist->count == 0)
272 return EXT2_ET_DBLIST_EMPTY;
273
274 if (entry)
275 *entry = dblist->list + ( dblist->count-1);
276 return 0;
277 }
278
ext2fs_dblist_drop_last(ext2_dblist dblist)279 errcode_t ext2fs_dblist_drop_last(ext2_dblist dblist)
280 {
281 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);
282
283 if (dblist->count == 0)
284 return EXT2_ET_DBLIST_EMPTY;
285
286 dblist->count--;
287 return 0;
288 }
289
290 /*
291 * Legacy 32-bit versions
292 */
293
294 /*
295 * Add a directory block to the directory block list
296 */
ext2fs_add_dir_block(ext2_dblist dblist,ext2_ino_t ino,blk_t blk,int blockcnt)297 errcode_t ext2fs_add_dir_block(ext2_dblist dblist, ext2_ino_t ino, blk_t blk,
298 int blockcnt)
299 {
300 return ext2fs_add_dir_block2(dblist, ino, blk, blockcnt);
301 }
302
303 /*
304 * Change the directory block to the directory block list
305 */
ext2fs_set_dir_block(ext2_dblist dblist,ext2_ino_t ino,blk_t blk,int blockcnt)306 errcode_t ext2fs_set_dir_block(ext2_dblist dblist, ext2_ino_t ino, blk_t blk,
307 int blockcnt)
308 {
309 return ext2fs_set_dir_block2(dblist, ino, blk, blockcnt);
310 }
311
ext2fs_dblist_sort(ext2_dblist dblist,EXT2_QSORT_TYPE (* sortfunc)(const void *,const void *))312 void ext2fs_dblist_sort(ext2_dblist dblist,
313 EXT2_QSORT_TYPE (*sortfunc)(const void *,
314 const void *))
315 {
316 if (sortfunc) {
317 sortfunc32 = sortfunc;
318 sortfunc = dir_block_cmp;
319 } else
320 sortfunc = dir_block_cmp2;
321 qsort(dblist->list, (size_t) dblist->count,
322 sizeof(struct ext2_db_entry2), sortfunc);
323 dblist->sorted = 1;
324 }
325
326 /*
327 * This function iterates over the directory block list
328 */
329 struct iterate_passthrough {
330 int (*func)(ext2_filsys fs,
331 struct ext2_db_entry *db_info,
332 void *priv_data);
333 void *priv_data;
334 };
335
passthrough_func(ext2_filsys fs,struct ext2_db_entry2 * db_info,void * priv_data)336 static int passthrough_func(ext2_filsys fs,
337 struct ext2_db_entry2 *db_info,
338 void *priv_data)
339 {
340 struct iterate_passthrough *p = priv_data;
341 struct ext2_db_entry db;
342 int ret;
343
344 db.ino = db_info->ino;
345 db.blk = (blk_t) db_info->blk;
346 db.blockcnt = (int) db_info->blockcnt;
347 ret = (p->func)(fs, &db, p->priv_data);
348 db_info->ino = db.ino;
349 db_info->blk = db.blk;
350 db_info->blockcnt = db.blockcnt;
351 return ret;
352 }
353
ext2fs_dblist_iterate(ext2_dblist dblist,int (* func)(ext2_filsys fs,struct ext2_db_entry * db_info,void * priv_data),void * priv_data)354 errcode_t ext2fs_dblist_iterate(ext2_dblist dblist,
355 int (*func)(ext2_filsys fs,
356 struct ext2_db_entry *db_info,
357 void *priv_data),
358 void *priv_data)
359 {
360 struct iterate_passthrough pass;
361
362 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);
363 pass.func = func;
364 pass.priv_data = priv_data;
365
366 return ext2fs_dblist_iterate2(dblist, passthrough_func, &pass);
367 }
368
dir_block_cmp(const void * a,const void * b)369 static EXT2_QSORT_TYPE dir_block_cmp(const void *a, const void *b)
370 {
371 const struct ext2_db_entry2 *db_a =
372 (const struct ext2_db_entry2 *) a;
373 const struct ext2_db_entry2 *db_b =
374 (const struct ext2_db_entry2 *) b;
375
376 struct ext2_db_entry a32, b32;
377
378 a32.ino = db_a->ino; a32.blk = db_a->blk;
379 a32.blockcnt = db_a->blockcnt;
380
381 b32.ino = db_b->ino; b32.blk = db_b->blk;
382 b32.blockcnt = db_b->blockcnt;
383
384 return sortfunc32(&a32, &b32);
385 }
386
ext2fs_dblist_count(ext2_dblist dblist)387 int ext2fs_dblist_count(ext2_dblist dblist)
388 {
389 return dblist->count;
390 }
391
ext2fs_dblist_get_last(ext2_dblist dblist,struct ext2_db_entry ** entry)392 errcode_t ext2fs_dblist_get_last(ext2_dblist dblist,
393 struct ext2_db_entry **entry)
394 {
395 static struct ext2_db_entry ret_entry;
396 struct ext2_db_entry2 *last;
397
398 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);
399
400 if (dblist->count == 0)
401 return EXT2_ET_DBLIST_EMPTY;
402
403 if (!entry)
404 return 0;
405
406 last = dblist->list + dblist->count -1;
407
408 ret_entry.ino = last->ino;
409 ret_entry.blk = last->blk;
410 ret_entry.blockcnt = last->blockcnt;
411 *entry = &ret_entry;
412
413 return 0;
414 }
415
416