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
|
/*
Unix SMB/CIFS implementation.
trivial database library - private includes
Copyright (C) Andrew Tridgell 2005
** NOTE! The following LGPL license applies to the tdb
** library. This does NOT imply that all of Samba is released
** under the LGPL
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 3 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "replace.h"
#include "system/filesys.h"
#include "system/time.h"
#include "system/shmem.h"
#include "system/select.h"
#include "system/wait.h"
#include "tdb.h"
#ifndef HAVE_GETPAGESIZE
#define getpagesize() 0x2000
#endif
typedef uint32_t tdb_len_t;
typedef uint32_t tdb_off_t;
#ifndef offsetof
#define offsetof(t,f) ((unsigned int)&((t *)0)->f)
#endif
#define TDB_MAGIC_FOOD "TDB file\n"
#define TDB_VERSION (0x26011967 + 6)
#define TDB_MAGIC (0x26011999U)
#define TDB_FREE_MAGIC (~TDB_MAGIC)
#define TDB_DEAD_MAGIC (0xFEE1DEAD)
#define TDB_RECOVERY_MAGIC (0xf53bc0e7U)
#define TDB_ALIGNMENT 4
#define DEFAULT_HASH_SIZE 131
#define FREELIST_TOP (sizeof(struct tdb_header))
#define TDB_ALIGN(x,a) (((x) + (a)-1) & ~((a)-1))
#define TDB_BYTEREV(x) (((((x)&0xff)<<24)|((x)&0xFF00)<<8)|(((x)>>8)&0xFF00)|((x)>>24))
#define TDB_DEAD(r) ((r)->magic == TDB_DEAD_MAGIC)
#define TDB_BAD_MAGIC(r) ((r)->magic != TDB_MAGIC && !TDB_DEAD(r))
#define TDB_HASH_TOP(hash) (FREELIST_TOP + (BUCKET(hash)+1)*sizeof(tdb_off_t))
#define TDB_HASHTABLE_SIZE(tdb) ((tdb->header.hash_size+1)*sizeof(tdb_off_t))
#define TDB_DATA_START(hash_size) (TDB_HASH_TOP(hash_size-1) + sizeof(tdb_off_t))
#define TDB_RECOVERY_HEAD offsetof(struct tdb_header, recovery_start)
#define TDB_SEQNUM_OFS offsetof(struct tdb_header, sequence_number)
#define TDB_PAD_BYTE 0x42
#define TDB_PAD_U32 0x42424242
/* NB assumes there is a local variable called "tdb" that is the
* current context, also takes doubly-parenthesized print-style
* argument. */
#define TDB_LOG(x) tdb->log.log_fn x
/* lock offsets */
#define GLOBAL_LOCK 0
#define ACTIVE_LOCK 4
#define TRANSACTION_LOCK 8
/* free memory if the pointer is valid and zero the pointer */
#ifndef SAFE_FREE
#define SAFE_FREE(x) do { if ((x) != NULL) {free(x); (x)=NULL;} } while(0)
#endif
#define BUCKET(hash) ((hash) % tdb->header.hash_size)
#define DOCONV() (tdb->flags & TDB_CONVERT)
#define CONVERT(x) (DOCONV() ? tdb_convert(&x, sizeof(x)) : &x)
/* the body of the database is made of one list_struct for the free space
plus a separate data list for each hash value */
struct list_struct {
tdb_off_t next; /* offset of the next record in the list */
tdb_len_t rec_len; /* total byte length of record */
tdb_len_t key_len; /* byte length of key */
tdb_len_t data_len; /* byte length of data */
uint32_t full_hash; /* the full 32 bit hash of the key */
uint32_t magic; /* try to catch errors */
/* the following union is implied:
union {
char record[rec_len];
struct {
char key[key_len];
char data[data_len];
}
uint32_t totalsize; (tailer)
}
*/
};
/* this is stored at the front of every database */
struct tdb_header {
char magic_food[32]; /* for /etc/magic */
uint32_t version; /* version of the code */
uint32_t hash_size; /* number of hash entries */
tdb_off_t rwlocks; /* obsolete - kept to detect old formats */
tdb_off_t recovery_start; /* offset of transaction recovery region */
tdb_off_t sequence_number; /* used when TDB_SEQNUM is set */
tdb_off_t reserved[29];
};
struct tdb_lock_type {
int list;
uint32_t count;
uint32_t ltype;
};
struct tdb_traverse_lock {
struct tdb_traverse_lock *next;
uint32_t off;
uint32_t hash;
int lock_rw;
};
struct tdb_methods {
int (*tdb_read)(struct tdb_context *, tdb_off_t , void *, tdb_len_t , int );
int (*tdb_write)(struct tdb_context *, tdb_off_t, const void *, tdb_len_t);
void (*next_hash_chain)(struct tdb_context *, uint32_t *);
int (*tdb_oob)(struct tdb_context *, tdb_off_t , int );
int (*tdb_expand_file)(struct tdb_context *, tdb_off_t , tdb_off_t );
int (*tdb_brlock)(struct tdb_context *, tdb_off_t , int, int, int, size_t);
};
struct tdb_context {
char *name; /* the name of the database */
void *map_ptr; /* where it is currently mapped */
int fd; /* open file descriptor for the database */
tdb_len_t map_size; /* how much space has been mapped */
int read_only; /* opened read-only */
int traverse_read; /* read-only traversal */
int traverse_write; /* read-write traversal */
struct tdb_lock_type global_lock;
int num_lockrecs;
struct tdb_lock_type *lockrecs; /* only real locks, all with count>0 */
enum TDB_ERROR ecode; /* error code for last tdb error */
struct tdb_header header; /* a cached copy of the header */
uint32_t flags; /* the flags passed to tdb_open */
struct tdb_traverse_lock travlocks; /* current traversal locks */
struct tdb_context *next; /* all tdbs to avoid multiple opens */
dev_t device; /* uniquely identifies this tdb */
ino_t inode; /* uniquely identifies this tdb */
struct tdb_logging_context log;
unsigned int (*hash_fn)(TDB_DATA *key);
int open_flags; /* flags used in the open - needed by reopen */
unsigned int num_locks; /* number of chain locks held */
const struct tdb_methods *methods;
struct tdb_transaction *transaction;
int page_size;
int max_dead_records;
bool have_transaction_lock;
volatile sig_atomic_t *interrupt_sig_ptr;
};
/*
internal prototypes
*/
int tdb_munmap(struct tdb_context *tdb);
void tdb_mmap(struct tdb_context *tdb);
int tdb_lock(struct tdb_context *tdb, int list, int ltype);
int tdb_lock_nonblock(struct tdb_context *tdb, int list, int ltype);
int tdb_unlock(struct tdb_context *tdb, int list, int ltype);
int tdb_brlock(struct tdb_context *tdb, tdb_off_t offset, int rw_type, int lck_type, int probe, size_t len);
int tdb_transaction_lock(struct tdb_context *tdb, int ltype);
int tdb_transaction_unlock(struct tdb_context *tdb);
int tdb_brlock_upgrade(struct tdb_context *tdb, tdb_off_t offset, size_t len);
int tdb_write_lock_record(struct tdb_context *tdb, tdb_off_t off);
int tdb_write_unlock_record(struct tdb_context *tdb, tdb_off_t off);
int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
void *tdb_convert(void *buf, uint32_t size);
int tdb_free(struct tdb_context *tdb, tdb_off_t offset, struct list_struct *rec);
tdb_off_t tdb_allocate(struct tdb_context *tdb, tdb_len_t length, struct list_struct *rec);
int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
int tdb_lock_record(struct tdb_context *tdb, tdb_off_t off);
int tdb_unlock_record(struct tdb_context *tdb, tdb_off_t off);
int tdb_rec_read(struct tdb_context *tdb, tdb_off_t offset, struct list_struct *rec);
int tdb_rec_write(struct tdb_context *tdb, tdb_off_t offset, struct list_struct *rec);
int tdb_do_delete(struct tdb_context *tdb, tdb_off_t rec_ptr, struct list_struct *rec);
unsigned char *tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t len);
int tdb_parse_data(struct tdb_context *tdb, TDB_DATA key,
tdb_off_t offset, tdb_len_t len,
int (*parser)(TDB_DATA key, TDB_DATA data,
void *private_data),
void *private_data);
tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash, int locktype,
struct list_struct *rec);
void tdb_io_init(struct tdb_context *tdb);
int tdb_expand(struct tdb_context *tdb, tdb_off_t size);
int tdb_rec_free_read(struct tdb_context *tdb, tdb_off_t off,
struct list_struct *rec);
|
