-
Notifications
You must be signed in to change notification settings - Fork 6
/
query.c
1393 lines (1188 loc) · 42.3 KB
/
query.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
mysqlfs - MySQL Filesystem
Copyright (C) 2006 Tsukasa Hamano <[email protected]>
Copyright (C) 2006,2007 Michal Ludvig <[email protected]>
$Id: query.c 55 2009-07-12 22:23:33Z chickenandporn $
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <time.h>
#include <libgen.h>
#include <fuse.h>
#ifdef HAVE_MYSQL_MYSQL_H
#include <mysql/mysql.h>
#endif
#ifdef HAVE_MYSQL_H
#include <mysql.h>
#endif
#include "mysqlfs.h"
#include "query.h"
#include "log.h"
#define SQL_MAX 10240
#define INODE_CACHE_MAX 4096
static inline int lock_inode(MYSQL *mysql, long inode)
{
// TODO
return 0;
}
static inline int unlock_inode(MYSQL *mysql, long inode)
{
// TODO
return 0;
}
static struct data_blocks_info *
fill_data_blocks_info(struct data_blocks_info *info, size_t size, off_t offset)
{
info->seq_first = offset / DATA_BLOCK_SIZE;
info->offset_first = offset % DATA_BLOCK_SIZE;
unsigned long nr_following_blocks = ((info->offset_first + size) / DATA_BLOCK_SIZE);
info->length_first = nr_following_blocks > 0 ? DATA_BLOCK_SIZE - info->offset_first : size;
info->seq_last = info->seq_first + nr_following_blocks;
info->length_last = (info->offset_first + size) % DATA_BLOCK_SIZE;
/* offset in last block (if it's a different one from the first block)
* is always 0 */
return info;
}
/**
* Get the attributes of an inode, filling in a struct stat. This function
* uses query_inode_full() to get the inode and nlinks of the given path, then
* reads the inode data from the database, storing this data into the provided
* structure.
*
* @return 0 if successful
* @return -EIO if the result of mysql_query() is non-zero
* @return -ENOENT if the inode at the give path is not found (actually, if the number of results is not exactly 1)
* @param mysql handle to connection to the database
* @param path pathname to check
* @param stbuf struct stat to fill with the inode contents
*/
int query_getattr(MYSQL *mysql, const char *path, struct stat *stbuf)
{
int ret;
long inode, nlinks;
char sql[SQL_MAX];
MYSQL_RES* result;
MYSQL_ROW row;
ret = query_inode_full(mysql, path, NULL, 0, &inode, NULL, &nlinks);
if (ret < 0)
return ret;
snprintf(sql, SQL_MAX,
"SELECT inode, mode, uid, gid, ctime, atime, mtime, size "
"FROM inodes WHERE inode=%ld",
inode);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret){
log_printf(LOG_ERROR, "ERROR: mysql_query()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
result = mysql_store_result(mysql);
if(!result){
log_printf(LOG_ERROR, "ERROR: mysql_store_result()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
if(mysql_num_rows(result) != 1){
mysql_free_result(result);
return -ENOENT;
}
row = mysql_fetch_row(result);
if(!row){
log_printf(LOG_ERROR, "ERROR: mysql_fetch_row()\n");
return -EIO;
}
stbuf->st_ino = inode;
stbuf->st_mode = atoi(row[1]);
stbuf->st_uid = atol(row[2]);
stbuf->st_gid = atol(row[3]);
stbuf->st_ctime = atol(row[4]);
stbuf->st_atime = atol(row[5]);
stbuf->st_mtime = atol(row[6]);
stbuf->st_size = atol(row[7]);
stbuf->st_nlink = nlinks;
mysql_free_result(result);
return 0;
}
/**
* Walk the directory tree to find the inode at the given absolute path,
* storing name, inode, parent inode, and number of links. Last developer of
* this function indicates that the pathname may overflow -- sounds like a
* good testcase :)
*
* If any of the name, inode, parent, or nlinks are given, those values will be
* recorded from the inode data to the given buffers. The name is written to
* the given name_len.
*
* @return 0 if successful
* @return -EIO if the result of mysql_query() is non-zero
* @return -ENOENT if the file at this path is not found
* @param mysql handle to connection to the database
* @param path (absolute) pathname of inode to find
* @param name destination to record (relative) name of the inode (may be NULL)
* @param name_len length of destination buffer "name"
* @param inode where to write the inode value, if found (may be NULL)
* @param parent where to write the parent's inode value, if found (may be NULL)
* @param nlinks where to write the number of links to the inode, if found (may be NULL)
*/
int query_inode_full(MYSQL *mysql, const char *path, char *name, size_t name_len,
long *inode, long *parent, long *nlinks)
{
long ret;
char sql[SQL_MAX*4];
MYSQL_RES* result;
MYSQL_ROW row;
int depth = 0;
char *pathptr = strdup(path), *pathptr_saved = pathptr;
char *nameptr, *saveptr = NULL;
char sql_from[SQL_MAX/3], sql_where[SQL_MAX/3];
char *sql_from_end = sql_from, *sql_where_end = sql_where;
char esc_name[PATH_MAX];
// TODO: Handle too long or too nested paths that don't fit in SQL_MAX!!!
sql_from_end += snprintf(sql_from_end, SQL_MAX, "tree AS t0");
sql_where_end += snprintf(sql_where_end, SQL_MAX, "t0.parent IS NULL");
while ((nameptr = strtok_r(pathptr, "/", &saveptr)) != NULL) {
if (depth++ == 0) {
pathptr = NULL;
}
if (strlen(nameptr) > 255) {
free(pathptr_saved);
return -ENAMETOOLONG;
}
mysql_real_escape_string(mysql, esc_name, nameptr, strlen(nameptr));
sql_from_end += snprintf(sql_from_end, SQL_MAX, " LEFT JOIN tree AS t%d ON t%d.inode = t%d.parent",
depth, depth-1, depth);
sql_where_end += snprintf(sql_where_end, SQL_MAX, " AND t%d.name = '%s'",
depth, esc_name);
}
free(pathptr_saved);
// TODO: Only run subquery when pointer to nlinks != NULL, otherwise we don't need it.
snprintf(sql, SQL_MAX, "SELECT t%d.inode, t%d.name, t%d.parent, "
" (SELECT COUNT(inode) FROM tree AS t%d WHERE t%d.inode=t%d.inode) "
" AS nlinks "
"FROM %s WHERE %s",
depth, depth, depth,
depth+1, depth+1, depth,
sql_from, sql_where);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret){
log_printf(LOG_ERROR, "ERROR: mysql_query()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
result = mysql_store_result(mysql);
if(!result){
log_printf(LOG_ERROR, "ERROR: mysql_store_result()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
if(mysql_num_rows(result) != 1){
mysql_free_result(result);
return -ENOENT;
}
row = mysql_fetch_row(result);
if(!row){
log_printf(LOG_ERROR, "ERROR: mysql_fetch_row()\n");
return -EIO;
}
log_printf(LOG_D_OTHER, "query_inode(path='%s') => %s, %s, %s, %s\n",
path, row[0], row[1], row[2], row[3]);
if (inode)
*inode = atol(row[0]);
if (name)
snprintf(name, name_len, "%s", row[1]);
if (parent)
*parent = row[2] ? atol(row[2]) : -1; /* parent may be NULL */
if (nlinks)
*nlinks = atol(row[3]);
mysql_free_result(result);
return 0;
}
/**
* Get the inode of a pathname. This is really a convenience function wrapping
* the query_inode_full() function, but can instead be used as a function with
* a nestable return value.
*
* @return ID of inode
* @return < 0 result of query_inode_full() if that function reports a failure
* @param mysql handle to connection to the database
* @param path (full) pathname of inode to find
*/
long query_inode(MYSQL *mysql, const char *path)
{
long inode, ret;
if (strlen(path) > PATH_MAX)
return -ENAMETOOLONG;
ret = query_inode_full(mysql, path, NULL, 0, &inode, NULL, NULL);
if (ret < 0)
return ret;
return inode;
}
/**
* Change the length of a file, truncating any additional data blocks and
* immediately deleting the data blocks past the truncation length. Function
* works by deleting whole blocks past the truncation point, limiting the
* partially-cleared block, and zeroing the extra part of the buffer.
* Called by mysqlfs_truncate().
*
* @see http://linux.die.net/man/2/truncate
*
* @return 0 on success; non-zero return of mysql_query() on error
* @param mysql handle to connection to the database
* @param inode node to operate on
* @param length new length of file
*/
int query_truncate(MYSQL *mysql, long inode, off_t length)
{
int ret;
char sql[SQL_MAX];
struct data_blocks_info info;
fill_data_blocks_info(&info, length, 0);
lock_inode(mysql, inode);
snprintf(sql, SQL_MAX,
"DELETE FROM data_blocks WHERE inode=%ld AND seq > %ld",
inode, info.seq_last);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
if ((ret = mysql_query(mysql, sql))) goto err_out;
snprintf(sql, SQL_MAX,
"UPDATE data_blocks SET data=RPAD(data, %zu, '\\0') "
"WHERE inode=%ld AND seq=%ld",
info.length_last, inode, info.seq_last);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
if ((ret = mysql_query(mysql, sql))) goto err_out;
snprintf(sql, SQL_MAX,
"UPDATE inodes SET size=%lld, mtime=UNIX_TIMESTAMP(NOW()), ctime=UNIX_TIMESTAMP(NOW()) WHERE inode=%ld",
(long long)length, inode);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
if ((ret = mysql_query(mysql, sql))) goto err_out;
unlock_inode(mysql, inode);
return 0;
err_out:
unlock_inode(mysql, inode);
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return ret;
}
/**
* The opposite of query_rmdirentry(), this function creates a directory in
* the tree with given inode and parent inode.
*
* @return 0 if successful
* @return -EIO if the result of mysql_query() is non-zero
* @param mysql handle to connection to the database
* @param inode inode of new directory
* @param name name (relative) of directory to create
* @param parent inode of directory holding the directory
*/
int query_mkdirentry(MYSQL *mysql, long inode, const char *name, long parent)
{
int ret;
char sql[SQL_MAX];
char esc_name[PATH_MAX * 2];
/*
* Should really update ctime in inode --- but if we did that we could
* add an nlinks count in the inode relation and get rid of the funcky join
*/
mysql_real_escape_string(mysql, esc_name, name, strlen(name));
snprintf(sql, SQL_MAX,
"INSERT INTO tree (name, parent, inode) VALUES ('%s', %ld, %ld)",
esc_name, parent, inode);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret) {
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
return 0;
}
/**
* The opposite of query_mkdirentry(), this function deletes a link
* from the tree with a parent that matches the inode given.
* It will refuse to delete an entry if it has children (i.e. is a
* non-empty directory)
*
* @return 0 if successful
* @return -EIO if the result of mysql_query() is non-zero
* @param mysql handle to connection to the database
* @param name name (relative) of directory to delete
* @param parent inode of directory holding the directory
*/
int query_rmdirentry(MYSQL *mysql, const char *name, long inode, long parent)
{
int ret;
MYSQL_RES *result;
char sql[SQL_MAX];
char esc_name[PATH_MAX * 2];
snprintf(sql, SQL_MAX, "select inode from tree where parent = %ld\n", inode);
ret = mysql_query(mysql, sql);
if(ret) {
log_printf(LOG_ERROR, "ERROR: mysql_query()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
result = mysql_store_result(mysql);
if(!result){
log_printf(LOG_ERROR, "ERROR: mysql_store_result()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
if (mysql_num_rows(result) != 0)
return -ENOTEMPTY;
mysql_real_escape_string(mysql, esc_name, name, strlen(name));
snprintf(sql, SQL_MAX,
"DELETE FROM tree WHERE name='%s' AND parent=%ld",
esc_name, parent);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret) {
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
return 0;
}
/**
* Create an inode. This function creates a child entry of the specified dev_t
* type and mode in the "parent" directory given as the "parent". Any parent
* directory information (ie "dirname(path)") is stripped out, leaving only
* the base pathname, but it has to be there (perhaps a bug?) since this
* function wants to strip out the path information that might conflict with
* the parent node's pathname.
*
* @see http://linux.die.net/man/2/mknod
*
* @return ID of new inode, or -ENOENT if the path contains no parent directory "/"
* @param mysql handle to connection to the database
* @param path name of directory to create
* @param mode access mode of new directory
* @param rdev type of inode to create
* @param parent inode of directory holding files (parent inode)
* @param alloc_data (unused)
*/
long query_mknod(MYSQL *mysql, const char *path, mode_t mode, dev_t rdev,
long parent, int alloc_data)
{
int ret;
char sql[SQL_MAX];
long new_inode_number = 0;
char *name, esc_name[PATH_MAX * 2];
if (path[0] == '/' && path[1] == '\0') {
snprintf(sql, SQL_MAX,
"INSERT INTO tree (name, parent) VALUES ('/', NULL)");
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret)
goto err_out;
} else {
name = strrchr(path, '/');
if (!name || *++name == '\0')
return -ENOENT;
if (strlen(name) > 255)
return -ENAMETOOLONG;
mysql_real_escape_string(mysql, esc_name, name, strlen(name));
snprintf(sql, SQL_MAX,
"INSERT INTO tree (name, parent) VALUES ('%s', %ld)",
esc_name, parent);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret)
goto err_out;
}
new_inode_number = mysql_insert_id(mysql);
snprintf(sql, SQL_MAX,
"INSERT INTO inodes(inode, mode, uid, gid, atime, ctime, mtime)"
"VALUES(%ld, %d, %d, %d, UNIX_TIMESTAMP(NOW()), "
"UNIX_TIMESTAMP(NOW()), UNIX_TIMESTAMP(NOW()))",
new_inode_number, mode,
fuse_get_context()->uid, fuse_get_context()->gid);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret)
goto err_out;
return new_inode_number;
err_out:
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return ret;
}
/**
* Create a directory. This is really a wrapper to a specific invocation of query_mknod().
*
* @see http://linux.die.net/man/2/mkdir
*
* @return ID of new inode, or -ENOENT if the path contains no parent directory "/"
* @param mysql handle to connection to the database
* @param path name of directory to create
* @param mode access mode of new directory
* @param parent inode of directory holding files (parent inode)
*/
long query_mkdir(MYSQL *mysql, const char *path, mode_t mode, long parent)
{
return query_mknod(mysql, path, S_IFDIR | mode, 0, parent, 0);
}
/**
* Read a directory. This is done by listing the nodes with a given node as
* parent, calling the filler parameter (pointer-to-function) for each item.
* The set of results is not ordered, so results would be in the "natural order"
* of the database.
*
* @see http://linux.die.net/man/2/readdir
*
* @return 0 on success; -EIO on failure (non-zero return from mysql_query() function)
* @param mysql handle to connection to the database
* @param inode inode of directory holding files (parent inode)
* @param buf buffer to pass to filler function
* @param filler fuse_fill_dir_t function-pointer used to process each directory entry
*/
int query_readdir(MYSQL *mysql, long inode, void *buf, fuse_fill_dir_t filler, int flag)
{
int ret;
char sql[SQL_MAX];
MYSQL_RES* result;
MYSQL_ROW row;
struct stat st;
snprintf(sql, sizeof(sql), "SELECT tree.name, tree.inode, inodes.mode FROM tree inner join inodes on tree.inode = inodes.inode WHERE tree.parent = '%ld'",
inode);
ret = mysql_query(mysql, sql);
if(ret){
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
result = mysql_store_result(mysql);
if(!result){
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
memset(&st, 0, sizeof st);
while((row = mysql_fetch_row(result)) != NULL){
st.st_ino = atol(row[1]);
st.st_mode = atol(row[2]);
filler(buf, (char*)basename(row[0]), &st, 0, 0);
}
mysql_free_result(result);
return 0;
}
/**
* Change the mode attribute in the inode entry. Should be the entry-point
* for the kernel's implementation of a chmod() call in an inode on the FUSE
* filesystem.
*
* @see http://linux.die.net/man/2/chmod
*
* @return 0 on success; -EIO on failure (non-zero return from mysql_query() function)
* @param mysql handle to connection to the database
* @param inode inode to update
* @param mode new mode to set into the inode
*/
int query_chmod(MYSQL *mysql, long inode, mode_t mode)
{
int ret;
char sql[SQL_MAX];
snprintf(sql, SQL_MAX,
"UPDATE inodes SET ctime=UNIX_TIMESTAMP(NOW()), mode=%d WHERE inode=%ld",
mode, inode);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret){
log_printf(LOG_ERROR, "Error: mysql_query()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
return 0;
}
/**
* Change the uid, gid attributes in the inode entry. Should be
* the entry-point for the kernel's implementation of a chown() call in an inode
* on the FUSE filesystem.
*
* @see http://linux.die.net/man/2/chown
*
* @return 0 on success; -EIO on failure (non-zero return from mysql_query() function)
* @param mysql handle to connection to the database
* @param inode inode to update
* @param uid uid to set (-1 to make no change to uid)
* @param gid gid to set (-1 to make no change to gid)
*/
int query_chown(MYSQL *mysql, long inode, uid_t uid, gid_t gid)
{
int ret;
char sql[SQL_MAX];
size_t index;
index = snprintf(sql, SQL_MAX, "UPDATE inodes SET ctime=UNIX_TIMESTAMP(NOW()),");
if (uid != (uid_t)-1)
index += snprintf(sql + index, SQL_MAX - index,
"uid=%d ", uid);
if (gid != (gid_t)-1)
index += snprintf(sql + index, SQL_MAX - index,
"%s gid=%d ",
/* Insert comma if this is a second argument */
(uid != (uid_t)-1) ? "," : "",
gid);
snprintf(sql + index, SQL_MAX - index, "WHERE inode=%ld", inode);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret){
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
return 0;
}
/**
* Change the utime attributes atime and mtime in the inode entry. Should be
* the entry-point for the kernel's implementation of a utime() call in an inode
* on the FUSE filesystem.
*
* @see http://linux.die.net/man/2/utime
* @see http://linux.die.net/man/2/stat
*
* @return 0 on success; -EIO on failure (non-zero return from mysql_query() function)
* @param mysql handle to connection to the database
* @param inode inode to update the atime, mtime
* @param time utimbuf with new actime, modtime, to set into access and modification times
*/
int query_utime(MYSQL *mysql, long inode, const struct timespec tv[2])
{
int ret;
char sql[SQL_MAX];
snprintf(sql, SQL_MAX,
"UPDATE inodes "
"SET atime=%ld, mtime=%ld "
"WHERE inode=%lu",
tv[0].tv_sec, tv[1].tv_sec, inode);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret){
log_printf(LOG_ERROR, "Error: mysql_query()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
return 0;
}
/**
* Read a number of bytes (perhaps larger than BLOCK_SIZE) at an offset from
* a file. The function does this by reading each block in succession, copying
* the block contents into the target buffer. The (offset % DATA_BLOCK_SIZE)
* issue is handled by shifting the copy slightly.
*
* @return < 0 in case of errors (propagating result of write_one_block() )
* @return > 0 number of bytes read (should equal size parameter)
* @param mysql handle to connection to the database
* @param inode inode of the file in question
* @param buf the buffer to copy read bytes
* @param size number of bytes to read
* @param offset offset within the file to read from
*/
int query_read(MYSQL *mysql, long inode, const char *buf, size_t size,
off_t offset)
{
int ret;
char sql[SQL_MAX];
MYSQL_RES* result;
MYSQL_ROW row;
unsigned long length = 0L, copy_len, seq;
struct data_blocks_info info;
char *dst = (char *)buf;
char *src, *zeroes = alloca(DATA_BLOCK_SIZE);
fill_data_blocks_info(&info, size, offset);
/* Read all required blocks */
snprintf(sql, SQL_MAX,
"SELECT seq, data, LENGTH(data) FROM data_blocks WHERE inode=%ld AND seq>=%lu AND seq <=%lu ORDER BY seq ASC",
inode, info.seq_first, info.seq_last);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
ret = mysql_query(mysql, sql);
if(ret){
log_printf(LOG_ERROR, "ERROR: mysql_query()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
result = mysql_store_result(mysql);
if(!result){
log_printf(LOG_ERROR, "ERROR: mysql_store_result()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
/* This is a bit tricky as we support 'sparse' files now.
* It means not all requested blocks must exist in the
* database. For those that don't exist we'll return
* a block of \0 instead. */
row = mysql_fetch_row(result);
memset(zeroes, 0L, DATA_BLOCK_SIZE);
for (seq = info.seq_first; seq<=info.seq_last; seq++) {
off_t row_seq = -1;
size_t row_len = DATA_BLOCK_SIZE;
char *data = zeroes;
if (row && (row_seq = atoll(row[0])) == seq) {
data = row[1];
row_len = atoll(row[2]);
}
if (seq == info.seq_first) {
if (row_len < info.offset_first)
goto go_away;
copy_len = MIN(row_len - info.offset_first, info.length_first);
src = data + info.offset_first;
} else if (seq == info.seq_last) {
copy_len = MIN(info.length_last, row_len);
src = data;
} else {
copy_len = MIN(DATA_BLOCK_SIZE, row_len);
src = data;
}
memcpy(dst, src, copy_len);
dst += copy_len;
length += copy_len;
if (row && row_seq == seq)
row = mysql_fetch_row(result);
}
go_away:
/* Read all remaining rows */
while (mysql_fetch_row(result));
mysql_free_result(result);
return length;
}
/**
* Writes a specific block into the database
*
* This function takes an early bail-out if the size to write is zero, or if the total size to write exceeds the block size.
*
* This function checks to see if the previous block didn't exist -- in such
* case, it then writes out a zero-length block. The function then creates a
* statement that has a '?' token representing the new data. If the previous
* data didn't exist, the function uses a "SET x == y" format; otherwise, a
* "CONCAT (data, ?)". The statement is snprintf'd, prepared, and executed; the
* result produces either a 0 on success, or a -EIO on failure (with an error
* message logged).
*
* @return 0 on success; -EIO on failure
* @param mysql handle to connection to the database
* @param inode inode to write out the data block on
* @param seq sequence number of datablock to write
* @param data buffer of content to write
* @param size size_t length of data
* @param offset what offset within the datablock to write the data
*/
static int write_one_block(MYSQL *mysql, long inode,
unsigned long seq,
const char *data, size_t size,
off_t offset)
{
MYSQL_STMT *stmt;
MYSQL_BIND bind[1];
char sql[SQL_MAX];
size_t current_block_size = query_size_block(mysql, inode, seq);
/* Shortcut */
if (size == 0) return 0;
if (offset + size > DATA_BLOCK_SIZE) {
log_printf(LOG_ERROR, "%s(): offset(%zu)+size(%zu)>max_block(%d)\n",
__func__, offset, size, DATA_BLOCK_SIZE);
return -EIO;
}
/* We expect the inode is already locked for this thread by caller! */
if (current_block_size == -ENXIO) {
/* This data block has not yet been allocated */
snprintf(sql, SQL_MAX,
"INSERT INTO data_blocks SET inode=%ld, seq=%lu, data=''", inode, seq);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
if(mysql_query(mysql, sql)){
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
current_block_size = query_size_block(mysql, inode, seq);
}
stmt = mysql_stmt_init(mysql);
if (!stmt)
{
log_printf(LOG_ERROR, "mysql_stmt_init(), out of memory\n");
return -EIO;
}
memset(bind, 0, sizeof(bind));
if (offset == 0 && current_block_size == 0) {
snprintf(sql, SQL_MAX,
"UPDATE data_blocks "
"SET data=? "
"WHERE inode=%ld AND seq=%lu",
inode, seq);
} else if (offset == current_block_size) {
snprintf(sql, sizeof(sql),
"UPDATE data_blocks "
"SET data=CONCAT(data, ?) "
"WHERE inode=%ld AND seq=%lu",
inode, seq);
} else {
size_t pos;
pos = snprintf(sql, sizeof(sql),
"UPDATE data_blocks SET data=CONCAT(");
if (offset > 0)
pos += snprintf(sql + pos, sizeof(sql) - pos, "RPAD(IF(ISNULL(data),'', data), %llu, '\\0'),", (long long)offset);
pos += snprintf(sql + pos, sizeof(sql) - pos, "?,");
if (offset + size < current_block_size) {
pos += snprintf(sql + pos, sizeof(sql) - pos, "SUBSTRING(data FROM %llu),", (long long)offset + size + 1);
}
sql[--pos] = '\0'; /* Remove the trailing comma. */
pos += snprintf(sql + pos, sizeof(sql) - pos, ") WHERE inode=%ld AND seq=%lu",
inode, seq);
}
log_printf(LOG_D_SQL, "sql=%s\n", sql);
if (mysql_stmt_prepare(stmt, sql, strlen(sql))) {
log_printf(LOG_ERROR, "mysql_stmt_prepare() failed: %s\n", mysql_stmt_error(stmt));
goto err_out;
}
if (mysql_stmt_param_count(stmt) != 1) {
log_printf(LOG_ERROR, "%s(): stmt_param_count=%d, expected 1\n", __func__, mysql_stmt_param_count(stmt));
return -EIO;
}
bind[0].buffer_type= MYSQL_TYPE_LONG_BLOB;
bind[0].buffer= (char *)data;
bind[0].is_null= 0;
bind[0].length= (unsigned long *)(void *)&size;
if (mysql_stmt_bind_param(stmt, bind)) {
log_printf(LOG_ERROR, "mysql_stmt_bind_param() failed: %s\n", mysql_stmt_error(stmt));
goto err_out;
}
/*
if (!mysql_stmt_send_long_data(stmt, 0, data, size))
{
log_printf(" send_long_data failed");
goto err_out;
}
*/
if (mysql_stmt_execute(stmt)) {
log_printf(LOG_ERROR, "mysql_stmt_execute() failed: %s\n", mysql_stmt_error(stmt));
goto err_out;
}
if (mysql_stmt_close(stmt))
log_printf(LOG_ERROR, "failed closing the statement: %s\n", mysql_stmt_error(stmt));
/* Update file size */
snprintf(sql, SQL_MAX,
"UPDATE inodes SET size=("
"SELECT seq*%d + LENGTH(data) FROM data_blocks WHERE inode=%ld AND seq=("
"SELECT MAX(seq) FROM data_blocks WHERE inode=%ld"
")"
") "
"WHERE inode=%ld",
DATA_BLOCK_SIZE, inode, inode, inode);
log_printf(LOG_D_SQL, "sql=%s\n", sql);
if(mysql_query(mysql, sql)) {
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
return size;
err_out:
log_printf(LOG_ERROR, " %s\n", mysql_stmt_error(stmt));
if (mysql_stmt_close(stmt))
log_printf(LOG_ERROR, "failed closing the statement: %s\n", mysql_stmt_error(stmt));
return -EIO;
}
/**
* Write a number of bytes (perhaps larger than BLOCK_SIZE) at an offset into
* a file. The function does this by writing the first partial block, then
* writing successive blocks until the full @c size is written.
*
* @return < 0 in case of errors (propagating result of write_one_block() )
* @return > 0 number of bytes written (should equal size parameter)
* @param mysql handle to connection to the database
* @param inode inode of the file in question
* @param data the buffer of data to write
* @param size number of bytes to write
* @param offset offset within the file to write to
*/
int query_write(MYSQL *mysql, long inode, const char *data, size_t size,
off_t offset)
{
struct data_blocks_info info;
unsigned long seq;
const char *ptr;
int ret, ret_size = 0;
fill_data_blocks_info(&info, size, offset);
/* Handle first block */
lock_inode(mysql, inode);
ret = write_one_block(mysql, inode, info.seq_first, data,
info.length_first, info.offset_first);
unlock_inode(mysql, inode);
if (ret < 0)
return ret;
ret_size = ret;
/* Shortcut - if last block seq is the same as first block
* seq simply go away as it's the same block */
if (info.seq_first == info.seq_last)
return ret_size;
ptr = data + info.length_first;
/* Handle all full-sized intermediate blocks */
for (seq = info.seq_first + 1; seq < info.seq_last; seq++) {
lock_inode(mysql, inode);
ret = write_one_block(mysql, inode, seq, ptr, DATA_BLOCK_SIZE, 0);
unlock_inode(mysql, inode);
if (ret < 0)
return ret;
ptr += DATA_BLOCK_SIZE;
ret_size += ret;
}
/* Handle last block */
lock_inode(mysql, inode);
ret = write_one_block(mysql, inode, info.seq_last, ptr,
info.length_last, 0);
unlock_inode(mysql, inode);
if (ret < 0)
return ret;
ret_size += ret;
return ret_size;
}
/**
* Check the size of a file. Check the value by reading the attribute stored
* in the inode table itself. The function does not summarize the size "live"
* by summing the size of each data block; rather this value is updated in
* query_fsck(), query_truncate(), write_one_block(). This trust in the
* various write functions optimizes this function's response time and
* reduces DB load.
*
* @return total size of the file at the inode as represented in the inode block
* @param mysql handle to connection to the database
* @param inode inode of the file in question
*/
ssize_t query_size(MYSQL *mysql, long inode)
{
size_t ret;
char sql[SQL_MAX];
MYSQL_RES *result;
MYSQL_ROW row;
snprintf(sql, SQL_MAX, "SELECT size FROM inodes WHERE inode=%ld",
inode);
ret = mysql_query(mysql, sql);
if(ret){
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
log_printf(LOG_D_SQL, "sql=%s\n", sql);
result = mysql_store_result(mysql);
if(!result){
log_printf(LOG_ERROR, "ERROR: mysql_store_result()\n");
log_printf(LOG_ERROR, "mysql_error: %s\n", mysql_error(mysql));
return -EIO;
}
if(mysql_num_rows(result) != 1 || mysql_num_fields(result) != 1){
mysql_free_result(result);
log_printf(LOG_ERROR, "ERROR: non-unique number of rows for %d\n", inode);