#ifndef TDB_PRIVATE_H
#define TDB_PRIVATE_H
/*
Trivial Database 2: private types and prototypes
Copyright (C) Rusty Russell 2010
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 .
*/
#define _XOPEN_SOURCE 500
#define _FILE_OFFSET_BITS 64
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include "config.h"
#include
#include
#include
#if HAVE_BYTESWAP_H
#include
#endif
#ifndef TEST_IT
#define TEST_IT(cond)
#endif
/* #define TDB_TRACE 1 */
#ifndef __STRING
#define __STRING(x) #x
#endif
#ifndef __STRINGSTRING
#define __STRINGSTRING(x) __STRING(x)
#endif
#ifndef __location__
#define __location__ __FILE__ ":" __STRINGSTRING(__LINE__)
#endif
typedef uint64_t tdb_len_t;
typedef uint64_t tdb_off_t;
#define TDB_MAGIC_FOOD "TDB file\n"
#define TDB_VERSION ((uint64_t)(0x26011967 + 7))
#define TDB_USED_MAGIC ((uint64_t)0x1999)
#define TDB_HTABLE_MAGIC ((uint64_t)0x1888)
#define TDB_CHAIN_MAGIC ((uint64_t)0x1777)
#define TDB_FTABLE_MAGIC ((uint64_t)0x1666)
#define TDB_FREE_MAGIC ((uint64_t)0xFE)
#define TDB_HASH_MAGIC (0xA1ABE11A01092008ULL)
#define TDB_RECOVERY_MAGIC (0xf53bc0e7ad124589ULL)
#define TDB_RECOVERY_INVALID_MAGIC (0x0ULL)
#define TDB_OFF_ERR ((tdb_off_t)-1)
/* Prevent others from opening the file. */
#define TDB_OPEN_LOCK 0
/* Doing a transaction. */
#define TDB_TRANSACTION_LOCK 1
/* Expanding file. */
#define TDB_EXPANSION_LOCK 2
/* Hash chain locks. */
#define TDB_HASH_LOCK_START 3
/* Range for hash locks. */
#define TDB_HASH_LOCK_RANGE_BITS 30
#define TDB_HASH_LOCK_RANGE (1 << TDB_HASH_LOCK_RANGE_BITS)
/* We have 1024 entries in the top level. */
#define TDB_TOPLEVEL_HASH_BITS 10
/* And 64 entries in each sub-level: thus 64 bits exactly after 9 levels. */
#define TDB_SUBLEVEL_HASH_BITS 6
/* And 8 entries in each group, ie 8 groups per sublevel. */
#define TDB_HASH_GROUP_BITS 3
/* This is currently 10: beyond this we chain. */
#define TDB_MAX_LEVELS (1+(64-TDB_TOPLEVEL_HASH_BITS) / TDB_SUBLEVEL_HASH_BITS)
/* Extend file by least 100 times larger than needed. */
#define TDB_EXTENSION_FACTOR 100
/* We steal bits from the offsets to store hash info. */
#define TDB_OFF_HASH_GROUP_MASK ((1ULL << TDB_HASH_GROUP_BITS) - 1)
/* We steal this many upper bits, giving a maximum offset of 64 exabytes. */
#define TDB_OFF_UPPER_STEAL 8
#define TDB_OFF_UPPER_STEAL_EXTRA 7
/* The bit number where we store extra hash bits. */
#define TDB_OFF_HASH_EXTRA_BIT 57
#define TDB_OFF_UPPER_STEAL_SUBHASH_BIT 56
/* The bit number where we store the extra hash bits. */
/* Convenience mask to get actual offset. */
#define TDB_OFF_MASK \
(((1ULL << (64 - TDB_OFF_UPPER_STEAL)) - 1) - TDB_OFF_HASH_GROUP_MASK)
/* How many buckets in a free list: see size_to_bucket(). */
#define TDB_FREE_BUCKETS (64 - TDB_OFF_UPPER_STEAL)
/* We have to be able to fit a free record here. */
#define TDB_MIN_DATA_LEN \
(sizeof(struct tdb_free_record) - sizeof(struct tdb_used_record))
/* Indicates this entry is not on an flist (can happen during coalescing) */
#define TDB_FTABLE_NONE ((1ULL << TDB_OFF_UPPER_STEAL) - 1)
#if !HAVE_BSWAP_64
static inline uint64_t bswap_64(uint64_t x)
{
return (((x&0x000000FFULL)<<56)
| ((x&0x0000FF00ULL)<<48)
| ((x&0x00FF0000ULL)<<40)
| ((x&0xFF000000ULL)<<32)
| ((x>>8)&0xFF000000ULL)
| ((x>>16)&0x00FF0000ULL)
| ((x>>24)&0x0000FF00ULL)
| ((x>>32)&0x000000FFULL));
}
#endif
struct tdb_used_record {
/* For on-disk compatibility, we avoid bitfields:
magic: 16, (highest)
key_len_bits: 5,
extra_padding: 32
hash_bits: 11
*/
uint64_t magic_and_meta;
/* The bottom key_len_bits*2 are key length, rest is data length. */
uint64_t key_and_data_len;
};
static inline unsigned rec_key_bits(const struct tdb_used_record *r)
{
return ((r->magic_and_meta >> 43) & ((1 << 5)-1)) * 2;
}
static inline uint64_t rec_key_length(const struct tdb_used_record *r)
{
return r->key_and_data_len & ((1ULL << rec_key_bits(r)) - 1);
}
static inline uint64_t rec_data_length(const struct tdb_used_record *r)
{
return r->key_and_data_len >> rec_key_bits(r);
}
static inline uint64_t rec_extra_padding(const struct tdb_used_record *r)
{
return (r->magic_and_meta >> 11) & 0xFFFFFFFF;
}
static inline uint32_t rec_hash(const struct tdb_used_record *r)
{
return r->magic_and_meta & ((1 << 11) - 1);
}
static inline uint16_t rec_magic(const struct tdb_used_record *r)
{
return (r->magic_and_meta >> 48);
}
struct tdb_free_record {
uint64_t magic_and_prev; /* TDB_OFF_UPPER_STEAL bits magic, then prev */
uint64_t ftable_and_len; /* Len not counting these two fields. */
/* This is why the minimum record size is 8 bytes. */
uint64_t next;
};
static inline uint64_t frec_prev(const struct tdb_free_record *f)
{
return f->magic_and_prev & ((1ULL << (64 - TDB_OFF_UPPER_STEAL)) - 1);
}
static inline uint64_t frec_magic(const struct tdb_free_record *f)
{
return f->magic_and_prev >> (64 - TDB_OFF_UPPER_STEAL);
}
static inline uint64_t frec_len(const struct tdb_free_record *f)
{
return f->ftable_and_len & ((1ULL << (64 - TDB_OFF_UPPER_STEAL))-1);
}
static inline unsigned frec_ftable(const struct tdb_free_record *f)
{
return f->ftable_and_len >> (64 - TDB_OFF_UPPER_STEAL);
}
struct tdb_recovery_record {
uint64_t magic;
/* Length of record. */
uint64_t max_len;
/* Length used. */
uint64_t len;
/* Old length of file before transaction. */
uint64_t eof;
};
/* If we bottom out of the subhashes, we chain. */
struct tdb_chain {
tdb_off_t rec[1 << TDB_HASH_GROUP_BITS];
tdb_off_t next;
};
/* this is stored at the front of every database */
struct tdb_header {
char magic_food[64]; /* for /etc/magic */
/* FIXME: Make me 32 bit? */
uint64_t version; /* version of the code */
uint64_t hash_test; /* result of hashing HASH_MAGIC. */
uint64_t hash_seed; /* "random" seed written at creation time. */
tdb_off_t free_table; /* (First) free table. */
tdb_off_t recovery; /* Transaction recovery area. */
tdb_off_t reserved[26];
/* Top level hash table. */
tdb_off_t hashtable[1ULL << TDB_TOPLEVEL_HASH_BITS];
};
struct tdb_freetable {
struct tdb_used_record hdr;
tdb_off_t next;
tdb_off_t buckets[TDB_FREE_BUCKETS];
};
/* Information about a particular (locked) hash entry. */
struct hash_info {
/* Full hash value of entry. */
uint64_t h;
/* Start and length of lock acquired. */
tdb_off_t hlock_start;
tdb_len_t hlock_range;
/* Start of hash group. */
tdb_off_t group_start;
/* Bucket we belong in. */
unsigned int home_bucket;
/* Bucket we (or an empty space) were found in. */
unsigned int found_bucket;
/* How many bits of the hash are already used. */
unsigned int hash_used;
/* Current working group. */
tdb_off_t group[1 << TDB_HASH_GROUP_BITS];
};
struct traverse_info {
struct traverse_level {
tdb_off_t hashtable;
/* We ignore groups here, and treat it as a big array. */
unsigned entry;
unsigned int total_buckets;
} levels[TDB_MAX_LEVELS + 1];
unsigned int num_levels;
unsigned int toplevel_group;
/* This makes delete-everything-inside-traverse work as expected. */
tdb_off_t prev;
};
enum tdb_lock_flags {
/* WAIT == F_SETLKW, NOWAIT == F_SETLK */
TDB_LOCK_NOWAIT = 0,
TDB_LOCK_WAIT = 1,
/* If set, don't log an error on failure. */
TDB_LOCK_PROBE = 2,
/* If set, don't check for recovery (used by recovery code). */
TDB_LOCK_NOCHECK = 4,
};
struct tdb_lock_type {
uint32_t off;
uint32_t count;
uint32_t ltype;
};
/* This is only needed for tdb_access_commit, but used everywhere to
* simplify. */
struct tdb_access_hdr {
struct tdb_access_hdr *next;
tdb_off_t off;
tdb_len_t len;
bool convert;
};
struct tdb_context {
/* Filename of the database. */
const char *name;
/* Mmap (if any), or malloc (for TDB_INTERNAL). */
void *map_ptr;
/* Are we accessing directly? (debugging check). */
int direct_access;
/* Open file descriptor (undefined for TDB_INTERNAL). */
int fd;
/* How much space has been mapped (<= current file size) */
tdb_len_t map_size;
/* Operating read-only? (Opened O_RDONLY, or in traverse_read) */
bool read_only;
/* mmap read only? */
int mmap_flags;
/* Error code for last tdb error. */
enum TDB_ERROR ecode;
/* the flags passed to tdb_open, for tdb_reopen. */
uint32_t flags;
/* Logging function */
void (*logfn)(struct tdb_context *tdb,
enum tdb_log_level level,
void *log_private,
const char *message);
void *log_private;
/* Hash function. */
uint64_t (*khash)(const void *key, size_t len, uint64_t seed, void *);
void *hash_priv;
uint64_t hash_seed;
/* Set if we are in a transaction. */
struct tdb_transaction *transaction;
/* What free table are we using? */
tdb_off_t ftable_off;
unsigned int ftable;
/* IO methods: changes for transactions. */
const struct tdb_methods *methods;
/* Lock information */
struct tdb_lock_type allrecord_lock;
size_t num_lockrecs;
struct tdb_lock_type *lockrecs;
struct tdb_attribute_stats *stats;
/* Direct access information */
struct tdb_access_hdr *access;
/* Single list of all TDBs, to avoid multiple opens. */
struct tdb_context *next;
dev_t device;
ino_t inode;
};
struct tdb_methods {
int (*tread)(struct tdb_context *, tdb_off_t, void *, tdb_len_t);
int (*twrite)(struct tdb_context *, tdb_off_t, const void *, tdb_len_t);
int (*oob)(struct tdb_context *, tdb_off_t, bool);
int (*expand_file)(struct tdb_context *, tdb_len_t);
void *(*direct)(struct tdb_context *, tdb_off_t, size_t, bool);
};
/*
internal prototypes
*/
/* hash.c: */
void tdb_hash_init(struct tdb_context *tdb);
/* Hash random memory. */
uint64_t tdb_hash(struct tdb_context *tdb, const void *ptr, size_t len);
/* Hash on disk. */
uint64_t hash_record(struct tdb_context *tdb, tdb_off_t off);
/* Find and lock a hash entry (or where it would be). */
tdb_off_t find_and_lock(struct tdb_context *tdb,
struct tdb_data key,
int ltype,
struct hash_info *h,
struct tdb_used_record *rec,
struct traverse_info *tinfo);
int replace_in_hash(struct tdb_context *tdb,
struct hash_info *h,
tdb_off_t new_off);
int add_to_hash(struct tdb_context *tdb, struct hash_info *h,
tdb_off_t new_off);
int delete_from_hash(struct tdb_context *tdb, struct hash_info *h);
/* For tdb_check */
bool is_subhash(tdb_off_t val);
/* free.c: */
int tdb_ftable_init(struct tdb_context *tdb);
/* check.c needs these to iterate through free lists. */
tdb_off_t first_ftable(struct tdb_context *tdb);
tdb_off_t next_ftable(struct tdb_context *tdb, tdb_off_t ftable);
/* This returns space or TDB_OFF_ERR. */
tdb_off_t alloc(struct tdb_context *tdb, size_t keylen, size_t datalen,
uint64_t hash, unsigned magic, bool growing);
/* Put this record in a free list. */
int add_free_record(struct tdb_context *tdb,
tdb_off_t off, tdb_len_t len_with_header);
/* Set up header for a used/ftable/htable/chain record. */
int set_header(struct tdb_context *tdb,
struct tdb_used_record *rec,
unsigned magic, uint64_t keylen, uint64_t datalen,
uint64_t actuallen, unsigned hashlow);
/* Used by tdb_check to verify. */
unsigned int size_to_bucket(tdb_len_t data_len);
tdb_off_t bucket_off(tdb_off_t ftable_off, unsigned bucket);
/* Used by tdb_summary */
size_t dead_space(struct tdb_context *tdb, tdb_off_t off);
/* io.c: */
/* Initialize tdb->methods. */
void tdb_io_init(struct tdb_context *tdb);
/* Convert endian of the buffer if required. */
void *tdb_convert(const struct tdb_context *tdb, void *buf, tdb_len_t size);
/* Unmap and try to map the tdb. */
void tdb_munmap(struct tdb_context *tdb);
void tdb_mmap(struct tdb_context *tdb);
/* Either alloc a copy, or give direct access. Release frees or noop. */
const void *tdb_access_read(struct tdb_context *tdb,
tdb_off_t off, tdb_len_t len, bool convert);
void *tdb_access_write(struct tdb_context *tdb,
tdb_off_t off, tdb_len_t len, bool convert);
/* Release result of tdb_access_read/write. */
void tdb_access_release(struct tdb_context *tdb, const void *p);
/* Commit result of tdb_acces_write. */
int tdb_access_commit(struct tdb_context *tdb, void *p);
/* Convenience routine to get an offset. */
tdb_off_t tdb_read_off(struct tdb_context *tdb, tdb_off_t off);
/* Write an offset at an offset. */
int tdb_write_off(struct tdb_context *tdb, tdb_off_t off, tdb_off_t val);
/* Clear an ondisk area. */
int zero_out(struct tdb_context *tdb, tdb_off_t off, tdb_len_t len);
/* Return a non-zero offset between >= start < end in this array (or end). */
tdb_off_t tdb_find_nonzero_off(struct tdb_context *tdb,
tdb_off_t base,
uint64_t start,
uint64_t end);
/* Return a zero offset in this array, or num. */
tdb_off_t tdb_find_zero_off(struct tdb_context *tdb, tdb_off_t off,
uint64_t num);
/* Allocate and make a copy of some offset. */
void *tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t len);
/* Writes a converted copy of a record. */
int tdb_write_convert(struct tdb_context *tdb, tdb_off_t off,
const void *rec, size_t len);
/* Reads record and converts it */
int tdb_read_convert(struct tdb_context *tdb, tdb_off_t off,
void *rec, size_t len);
/* Adds a stat, if it's in range. */
void add_stat_(struct tdb_context *tdb, uint64_t *stat, size_t val);
#define add_stat(tdb, statname, val) \
do { \
if (unlikely((tdb)->stats)) \
add_stat_((tdb), &(tdb)->stats->statname, (val)); \
} while (0)
/* lock.c: */
void tdb_lock_init(struct tdb_context *tdb);
/* Lock/unlock a range of hashes. */
int tdb_lock_hashes(struct tdb_context *tdb,
tdb_off_t hash_lock, tdb_len_t hash_range,
int ltype, enum tdb_lock_flags waitflag);
int tdb_unlock_hashes(struct tdb_context *tdb,
tdb_off_t hash_lock,
tdb_len_t hash_range, int ltype);
/* Lock/unlock a particular free bucket. */
int tdb_lock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off,
enum tdb_lock_flags waitflag);
void tdb_unlock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off);
/* Serialize transaction start. */
int tdb_transaction_lock(struct tdb_context *tdb, int ltype);
int tdb_transaction_unlock(struct tdb_context *tdb, int ltype);
/* Do we have any hash locks (ie. via tdb_chainlock) ? */
bool tdb_has_hash_locks(struct tdb_context *tdb);
/* Lock entire database. */
int tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
enum tdb_lock_flags flags, bool upgradable);
int tdb_allrecord_unlock(struct tdb_context *tdb, int ltype);
int tdb_allrecord_upgrade(struct tdb_context *tdb);
/* Serialize db open. */
int tdb_lock_open(struct tdb_context *tdb, enum tdb_lock_flags flags);
void tdb_unlock_open(struct tdb_context *tdb);
bool tdb_has_open_lock(struct tdb_context *tdb);
/* Serialize db expand. */
int tdb_lock_expand(struct tdb_context *tdb, int ltype);
void tdb_unlock_expand(struct tdb_context *tdb, int ltype);
bool tdb_has_expansion_lock(struct tdb_context *tdb);
/* If it needs recovery, grab all the locks and do it. */
int tdb_lock_and_recover(struct tdb_context *tdb);
/* traverse.c: */
int first_in_hash(struct tdb_context *tdb, int ltype,
struct traverse_info *tinfo,
TDB_DATA *kbuf, size_t *dlen);
int next_in_hash(struct tdb_context *tdb, int ltype,
struct traverse_info *tinfo,
TDB_DATA *kbuf, size_t *dlen);
/* transaction.c: */
int tdb_transaction_recover(struct tdb_context *tdb);
bool tdb_needs_recovery(struct tdb_context *tdb);
/* tdb.c: */
void COLD tdb_logerr(struct tdb_context *tdb,
enum TDB_ERROR ecode,
enum tdb_log_level level,
const char *fmt, ...);
#ifdef TDB_TRACE
void tdb_trace(struct tdb_context *tdb, const char *op);
void tdb_trace_seqnum(struct tdb_context *tdb, uint32_t seqnum, const char *op);
void tdb_trace_open(struct tdb_context *tdb, const char *op,
unsigned hash_size, unsigned tdb_flags, unsigned open_flags);
void tdb_trace_ret(struct tdb_context *tdb, const char *op, int ret);
void tdb_trace_retrec(struct tdb_context *tdb, const char *op, TDB_DATA ret);
void tdb_trace_1rec(struct tdb_context *tdb, const char *op,
TDB_DATA rec);
void tdb_trace_1rec_ret(struct tdb_context *tdb, const char *op,
TDB_DATA rec, int ret);
void tdb_trace_1rec_retrec(struct tdb_context *tdb, const char *op,
TDB_DATA rec, TDB_DATA ret);
void tdb_trace_2rec_flag_ret(struct tdb_context *tdb, const char *op,
TDB_DATA rec1, TDB_DATA rec2, unsigned flag,
int ret);
void tdb_trace_2rec_retrec(struct tdb_context *tdb, const char *op,
TDB_DATA rec1, TDB_DATA rec2, TDB_DATA ret);
#else
#define tdb_trace(tdb, op)
#define tdb_trace_seqnum(tdb, seqnum, op)
#define tdb_trace_open(tdb, op, hash_size, tdb_flags, open_flags)
#define tdb_trace_ret(tdb, op, ret)
#define tdb_trace_retrec(tdb, op, ret)
#define tdb_trace_1rec(tdb, op, rec)
#define tdb_trace_1rec_ret(tdb, op, rec, ret)
#define tdb_trace_1rec_retrec(tdb, op, rec, ret)
#define tdb_trace_2rec_flag_ret(tdb, op, rec1, rec2, flag, ret)
#define tdb_trace_2rec_retrec(tdb, op, rec1, rec2, ret)
#endif /* !TDB_TRACE */
#endif