2 Unix SMB/CIFS implementation.
4 trivial database library - private includes
6 Copyright (C) Andrew Tridgell 2005
8 ** NOTE! The following LGPL license applies to the tdb
9 ** library. This does NOT imply that all of Samba is released
12 This library is free software; you can redistribute it and/or
13 modify it under the terms of the GNU Lesser General Public
14 License as published by the Free Software Foundation; either
15 version 2 of the License, or (at your option) any later version.
17 This library is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 Lesser General Public License for more details.
22 You should have received a copy of the GNU Lesser General Public
23 License along with this library; if not, write to the Free Software
24 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
32 #define _XOPEN_SOURCE 500
50 #include "lib/tdb/include/tdb.h"
51 #include "system/time.h"
52 #include "system/shmem.h"
53 #include "system/filesys.h"
60 typedef u32 tdb_len_t;
61 typedef u32 tdb_off_t;
64 #define offsetof(t,f) ((unsigned int)&((t *)0)->f)
67 #define TDB_MAGIC_FOOD "TDB file\n"
68 #define TDB_VERSION (0x26011967 + 6)
69 #define TDB_MAGIC (0x26011999U)
70 #define TDB_FREE_MAGIC (~TDB_MAGIC)
71 #define TDB_DEAD_MAGIC (0xFEE1DEAD)
72 #define TDB_RECOVERY_MAGIC (0xf53bc0e7U)
73 #define TDB_ALIGNMENT 4
74 #define MIN_REC_SIZE (2*sizeof(struct list_struct) + TDB_ALIGNMENT)
75 #define DEFAULT_HASH_SIZE 131
76 #define FREELIST_TOP (sizeof(struct tdb_header))
77 #define TDB_ALIGN(x,a) (((x) + (a)-1) & ~((a)-1))
78 #define TDB_BYTEREV(x) (((((x)&0xff)<<24)|((x)&0xFF00)<<8)|(((x)>>8)&0xFF00)|((x)>>24))
79 #define TDB_DEAD(r) ((r)->magic == TDB_DEAD_MAGIC)
80 #define TDB_BAD_MAGIC(r) ((r)->magic != TDB_MAGIC && !TDB_DEAD(r))
81 #define TDB_HASH_TOP(hash) (FREELIST_TOP + (BUCKET(hash)+1)*sizeof(tdb_off_t))
82 #define TDB_HASHTABLE_SIZE(tdb) ((tdb->header.hash_size+1)*sizeof(tdb_off_t))
83 #define TDB_DATA_START(hash_size) TDB_HASH_TOP(hash_size-1)
84 #define TDB_RECOVERY_HEAD offsetof(struct tdb_header, recovery_start)
85 #define TDB_PAD_BYTE 0x42
86 #define TDB_PAD_U32 0x42424242
88 /* NB assumes there is a local variable called "tdb" that is the
89 * current context, also takes doubly-parenthesized print-style
91 #define TDB_LOG(x) tdb->log_fn x
96 #define TRANSACTION_LOCK 8
103 #define MAP_FAILED ((void *)-1)
106 #ifndef discard_const_p
107 # if defined(__intptr_t_defined) || defined(HAVE_INTPTR_T)
108 # define discard_const(ptr) ((void *)((intptr_t)(ptr)))
110 # define discard_const(ptr) ((void *)(ptr))
112 # define discard_const_p(type, ptr) ((type *)discard_const(ptr))
115 /* free memory if the pointer is valid and zero the pointer */
117 #define SAFE_FREE(x) do { if ((x) != NULL) {free(discard_const_p(void *, (x))); (x)=NULL;} } while(0)
120 #define BUCKET(hash) ((hash) % tdb->header.hash_size)
122 #define DOCONV() (tdb->flags & TDB_CONVERT)
123 #define CONVERT(x) (DOCONV() ? tdb_convert(&x, sizeof(x)) : &x)
126 /* the body of the database is made of one list_struct for the free space
127 plus a separate data list for each hash value */
129 tdb_off_t next; /* offset of the next record in the list */
130 tdb_len_t rec_len; /* total byte length of record */
131 tdb_len_t key_len; /* byte length of key */
132 tdb_len_t data_len; /* byte length of data */
133 u32 full_hash; /* the full 32 bit hash of the key */
134 u32 magic; /* try to catch errors */
135 /* the following union is implied:
137 char record[rec_len];
142 u32 totalsize; (tailer)
148 /* this is stored at the front of every database */
150 char magic_food[32]; /* for /etc/magic */
151 u32 version; /* version of the code */
152 u32 hash_size; /* number of hash entries */
153 tdb_off_t rwlocks; /* obsolete - kept to detect old formats */
154 tdb_off_t recovery_start; /* offset of transaction recovery region */
155 tdb_off_t reserved[30];
158 struct tdb_lock_type {
163 struct tdb_traverse_lock {
164 struct tdb_traverse_lock *next;
172 int (*tdb_read)(struct tdb_context *, tdb_off_t , void *, tdb_len_t , int );
173 int (*tdb_write)(struct tdb_context *, tdb_off_t, const void *, tdb_len_t);
174 void (*next_hash_chain)(struct tdb_context *, u32 *);
175 int (*tdb_oob)(struct tdb_context *, tdb_off_t , int );
176 int (*tdb_expand_file)(struct tdb_context *, tdb_off_t , tdb_off_t );
177 int (*tdb_brlock)(struct tdb_context *, tdb_off_t , int, int, int);
181 char *name; /* the name of the database */
182 void *map_ptr; /* where it is currently mapped */
183 int fd; /* open file descriptor for the database */
184 tdb_len_t map_size; /* how much space has been mapped */
185 int read_only; /* opened read-only */
186 struct tdb_lock_type *locked; /* array of chain locks */
187 enum TDB_ERROR ecode; /* error code for last tdb error */
188 struct tdb_header header; /* a cached copy of the header */
189 u32 flags; /* the flags passed to tdb_open */
190 struct tdb_traverse_lock travlocks; /* current traversal locks */
191 struct tdb_context *next; /* all tdbs to avoid multiple opens */
192 dev_t device; /* uniquely identifies this tdb */
193 ino_t inode; /* uniquely identifies this tdb */
194 void (*log_fn)(struct tdb_context *tdb, int level, const char *, ...) PRINTF_ATTRIBUTE(3,4); /* logging function */
195 unsigned int (*hash_fn)(TDB_DATA *key);
196 int open_flags; /* flags used in the open - needed by reopen */
197 unsigned int num_locks; /* number of chain locks held */
198 const struct tdb_methods *methods;
199 struct tdb_transaction *transaction;
207 int tdb_munmap(struct tdb_context *tdb);
208 void tdb_mmap(struct tdb_context *tdb);
209 int tdb_lock(struct tdb_context *tdb, int list, int ltype);
210 int tdb_unlock(struct tdb_context *tdb, int list, int ltype);
211 int tdb_brlock(struct tdb_context *tdb, tdb_off_t offset, int rw_type, int lck_type, int probe);
212 int tdb_brlock_len(struct tdb_context *tdb, tdb_off_t offset,
213 int rw_type, int lck_type, int probe, size_t len);
214 int tdb_write_lock_record(struct tdb_context *tdb, tdb_off_t off);
215 int tdb_write_unlock_record(struct tdb_context *tdb, tdb_off_t off);
216 int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
217 int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
218 void *tdb_convert(void *buf, u32 size);
219 int tdb_free(struct tdb_context *tdb, tdb_off_t offset, struct list_struct *rec);
220 tdb_off_t tdb_allocate(struct tdb_context *tdb, tdb_len_t length, struct list_struct *rec);
221 int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
222 int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
223 int tdb_lock_record(struct tdb_context *tdb, tdb_off_t off);
224 int tdb_unlock_record(struct tdb_context *tdb, tdb_off_t off);
225 int tdb_rec_read(struct tdb_context *tdb, tdb_off_t offset, struct list_struct *rec);
226 int tdb_rec_write(struct tdb_context *tdb, tdb_off_t offset, struct list_struct *rec);
227 int tdb_do_delete(struct tdb_context *tdb, tdb_off_t rec_ptr, struct list_struct *rec);
228 unsigned char *tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t len);
229 tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, u32 hash, int locktype,
230 struct list_struct *rec);
231 void tdb_io_init(struct tdb_context *tdb);
232 int tdb_expand(struct tdb_context *tdb, tdb_off_t size);