+++ /dev/null
-#ifndef CCAN_NTDB_H
-#define CCAN_NTDB_H
-
-/*
- NTDB: trivial database library version 2
-
- Copyright (C) Andrew Tridgell 1999-2004
- Copyright (C) Rusty Russell 2010-2012
-
- ** NOTE! The following LGPL license applies to the ntdb
- ** 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/>.
-*/
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#ifdef HAVE_LIBREPLACE
-#include <replace.h>
-#include <system/filesys.h>
-#else
-#include "config.h"
-#if HAVE_FILE_OFFSET_BITS
-#define _FILE_OFFSET_BITS 64
-#endif
-
-#ifndef _PUBLIC_
-#ifdef HAVE_VISIBILITY_ATTR
-#define _PUBLIC_ __attribute__((visibility("default")))
-#else
-#define _PUBLIC_
-#endif
-#endif
-
-/* For mode_t */
-#include <sys/types.h>
-/* For O_* flags. */
-#include <sys/stat.h>
-/* For sig_atomic_t. */
-#include <signal.h>
-/* For uint64_t */
-#include <stdint.h>
-/* For bool */
-#include <stdbool.h>
-/* For memcmp */
-#include <string.h>
-#endif
-
-#include <ccan/compiler/compiler.h>
-#include <ccan/typesafe_cb/typesafe_cb.h>
-#include <ccan/cast/cast.h>
-
-union ntdb_attribute;
-struct ntdb_context;
-
-/**
- * struct TDB_DATA - (n)tdb data blob
- *
- * To ease compatibility, we use 'struct TDB_DATA' from tdb.h, so if
- * you want to include both tdb.h and ntdb.h, you need to #include
- * tdb.h first.
- */
-#ifndef __TDB_H__
-struct TDB_DATA {
- unsigned char *dptr;
- size_t dsize;
-};
-#endif
-
-typedef struct TDB_DATA NTDB_DATA;
-
-/**
- * ntdb_open - open a database file
- * @name: the file name (or database name if flags contains NTDB_INTERNAL)
- * @ntdb_flags: options for this database
- * @open_flags: flags argument for ntdb's open() call.
- * @mode: mode argument for ntdb's open() call.
- * @attributes: linked list of extra attributes for this ntdb.
- *
- * This call opens (and potentially creates) a database file.
- * Multiple processes can have the NTDB file open at once.
- *
- * On failure it will return NULL, and set errno: it may also call
- * any log attribute found in @attributes.
- *
- * See also:
- * union ntdb_attribute
- */
-struct ntdb_context *ntdb_open(const char *name, int ntdb_flags,
- int open_flags, mode_t mode,
- union ntdb_attribute *attributes);
-
-
-/* flags for ntdb_open() */
-#define NTDB_DEFAULT 0 /* just a readability place holder */
-#define NTDB_INTERNAL 2 /* don't store on disk */
-#define NTDB_NOLOCK 4 /* don't do any locking */
-#define NTDB_NOMMAP 8 /* don't use mmap */
-#define NTDB_CONVERT 16 /* convert endian */
-#define NTDB_NOSYNC 64 /* don't use synchronous transactions */
-#define NTDB_SEQNUM 128 /* maintain a sequence number */
-#define NTDB_ALLOW_NESTING 256 /* fake nested transactions */
-#define NTDB_RDONLY 512 /* implied by O_RDONLY */
-#define NTDB_CANT_CHECK 2048 /* has a feature which we don't understand */
-
-/**
- * ntdb_close - close and free a ntdb.
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This always succeeds, in that @ntdb is unusable after this call. But if
- * some unexpected error occurred while closing, it will return non-zero
- * (the only clue as to cause will be via the log attribute).
- */
-int ntdb_close(struct ntdb_context *ntdb);
-
-/**
- * enum NTDB_ERROR - error returns for NTDB
- *
- * See Also:
- * ntdb_errorstr()
- */
-enum NTDB_ERROR {
- NTDB_SUCCESS = 0, /* No error. */
- NTDB_ERR_CORRUPT = -1, /* We read the db, and it was bogus. */
- NTDB_ERR_IO = -2, /* We couldn't read/write the db. */
- NTDB_ERR_LOCK = -3, /* Locking failed. */
- NTDB_ERR_OOM = -4, /* Out of Memory. */
- NTDB_ERR_EXISTS = -5, /* The key already exists. */
- NTDB_ERR_NOEXIST = -6, /* The key does not exist. */
- NTDB_ERR_EINVAL = -7, /* You're using it wrong. */
- NTDB_ERR_RDONLY = -8, /* The database is read-only. */
- NTDB_ERR_LAST = NTDB_ERR_RDONLY
-};
-
-/**
- * ntdb_store - store a key/value pair in a ntdb.
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key
- * @dbuf: the data to associate with the key.
- * @flag: NTDB_REPLACE, NTDB_INSERT or NTDB_MODIFY.
- *
- * This inserts (or overwrites) a key/value pair in the NTDB. If flag
- * is NTDB_REPLACE, it doesn't matter whether the key exists or not;
- * NTDB_INSERT means it must not exist (returns NTDB_ERR_EXISTS otherwise),
- * and NTDB_MODIFY means it must exist (returns NTDB_ERR_NOEXIST otherwise).
- *
- * On success, this returns NTDB_SUCCESS.
- *
- * See also:
- * ntdb_fetch, ntdb_transaction_start, ntdb_append, ntdb_delete.
- */
-enum NTDB_ERROR ntdb_store(struct ntdb_context *ntdb,
- NTDB_DATA key,
- NTDB_DATA dbuf,
- int flag);
-
-/* flags to ntdb_store() */
-#define NTDB_REPLACE 1 /* A readability place holder */
-#define NTDB_INSERT 2 /* Don't overwrite an existing entry */
-#define NTDB_MODIFY 3 /* Don't create an existing entry */
-
-/**
- * ntdb_fetch - fetch a value from a ntdb.
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key
- * @data: pointer to data.
- *
- * This looks up a key in the database and sets it in @data.
- *
- * If it returns NTDB_SUCCESS, the key was found: it is your
- * responsibility to call free() on @data->dptr.
- *
- * Otherwise, it returns an error (usually, NTDB_ERR_NOEXIST) and @data is
- * undefined.
- */
-enum NTDB_ERROR ntdb_fetch(struct ntdb_context *ntdb, NTDB_DATA key,
- NTDB_DATA *data);
-
-/**
- * ntdb_errorstr - map the ntdb error onto a constant readable string
- * @ecode: the enum NTDB_ERROR to map.
- *
- * This is useful for displaying errors to users.
- */
-const char *ntdb_errorstr(enum NTDB_ERROR ecode);
-
-/**
- * ntdb_append - append a value to a key/value pair in a ntdb.
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key
- * @dbuf: the data to append.
- *
- * This is equivalent to fetching a record, reallocating .dptr to add the
- * data, and writing it back, only it's much more efficient. If the key
- * doesn't exist, it's equivalent to ntdb_store (with an additional hint that
- * you expect to expand the record in future).
- *
- * See Also:
- * ntdb_fetch(), ntdb_store()
- */
-enum NTDB_ERROR ntdb_append(struct ntdb_context *ntdb,
- NTDB_DATA key, NTDB_DATA dbuf);
-
-/**
- * ntdb_delete - delete a key from a ntdb.
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key to delete.
- *
- * Returns NTDB_SUCCESS on success, or an error (usually NTDB_ERR_NOEXIST).
- *
- * See Also:
- * ntdb_fetch(), ntdb_store()
- */
-enum NTDB_ERROR ntdb_delete(struct ntdb_context *ntdb, NTDB_DATA key);
-
-/**
- * ntdb_exists - does a key exist in the database?
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key to search for.
- *
- * Returns true if it exists, or false if it doesn't or any other error.
- */
-bool ntdb_exists(struct ntdb_context *ntdb, NTDB_DATA key);
-
-/**
- * ntdb_deq - are NTDB_DATA equal?
- * @a: one NTDB_DATA
- * @b: another NTDB_DATA
- */
-static inline bool ntdb_deq(NTDB_DATA a, NTDB_DATA b)
-{
- return a.dsize == b.dsize && memcmp(a.dptr, b.dptr, a.dsize) == 0;
-}
-
-/**
- * ntdb_mkdata - make a NTDB_DATA from const data
- * @p: the constant pointer
- * @len: the length
- *
- * As the dptr member of NTDB_DATA is not constant, you need to
- * cast it. This function keeps thost casts in one place, as well as
- * suppressing the warning some compilers give when casting away a
- * qualifier (eg. gcc with -Wcast-qual)
- */
-static inline NTDB_DATA ntdb_mkdata(const void *p, size_t len)
-{
- NTDB_DATA d;
- d.dptr = cast_const(void *, p);
- d.dsize = len;
- return d;
-}
-
-/**
- * ntdb_transaction_start - start a transaction
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This begins a series of atomic operations. Other processes will be able
- * to read the ntdb, but not alter it (they will block), nor will they see
- * any changes until ntdb_transaction_commit() is called.
- *
- * Note that if the NTDB_ALLOW_NESTING flag is set, a ntdb_transaction_start()
- * within a transaction will succeed, but it's not a real transaction:
- * (1) An inner transaction which is committed is not actually committed until
- * the outer transaction is; if the outer transaction is cancelled, the
- * inner ones are discarded.
- * (2) ntdb_transaction_cancel() marks the outer transaction as having an error,
- * so the final ntdb_transaction_commit() will fail.
- * (3) the outer transaction will see the results of the inner transaction.
- *
- * See Also:
- * ntdb_transaction_cancel, ntdb_transaction_commit.
- */
-enum NTDB_ERROR ntdb_transaction_start(struct ntdb_context *ntdb);
-
-/**
- * ntdb_transaction_cancel - abandon a transaction
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This aborts a transaction, discarding any changes which were made.
- * ntdb_close() does this implicitly.
- */
-void ntdb_transaction_cancel(struct ntdb_context *ntdb);
-
-/**
- * ntdb_transaction_commit - commit a transaction
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This completes a transaction, writing any changes which were made.
- *
- * fsync() is used to commit the transaction (unless NTDB_NOSYNC is set),
- * making it robust against machine crashes, but very slow compared to
- * other NTDB operations.
- *
- * A failure can only be caused by unexpected errors (eg. I/O or
- * memory); this is no point looping on transaction failure.
- *
- * See Also:
- * ntdb_transaction_prepare_commit()
- */
-enum NTDB_ERROR ntdb_transaction_commit(struct ntdb_context *ntdb);
-
-/**
- * ntdb_transaction_prepare_commit - prepare to commit a transaction
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This ensures we have the resources to commit a transaction (using
- * ntdb_transaction_commit): if this succeeds then a transaction will only
- * fail if the write() or fsync() calls fail.
- *
- * If this fails you must still call ntdb_transaction_cancel() to cancel
- * the transaction.
- *
- * See Also:
- * ntdb_transaction_commit()
- */
-enum NTDB_ERROR ntdb_transaction_prepare_commit(struct ntdb_context *ntdb);
-
-/**
- * ntdb_traverse - traverse a NTDB
- * @ntdb: the ntdb context returned from ntdb_open()
- * @fn: the function to call for every key/value pair (or NULL)
- * @p: the pointer to hand to @f
- *
- * This walks the NTDB until all they keys have been traversed, or @fn
- * returns non-zero. If the traverse function or other processes are
- * changing data or adding or deleting keys, the traverse may be
- * unreliable: keys may be skipped or (rarely) visited twice.
- *
- * There is one specific exception: the special case of deleting the
- * current key does not undermine the reliability of the traversal.
- *
- * On success, returns the number of keys iterated. On error returns
- * a negative enum NTDB_ERROR value.
- */
-#define ntdb_traverse(ntdb, fn, p) \
- ntdb_traverse_(ntdb, typesafe_cb_preargs(int, void *, (fn), (p), \
- struct ntdb_context *, \
- NTDB_DATA, NTDB_DATA), (p))
-
-int64_t ntdb_traverse_(struct ntdb_context *ntdb,
- int (*fn)(struct ntdb_context *,
- NTDB_DATA, NTDB_DATA, void *), void *p);
-
-/**
- * ntdb_parse_record - operate directly on data in the database.
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key whose record we should hand to @parse
- * @parse: the function to call for the data
- * @data: the private pointer to hand to @parse (types must match).
- *
- * This avoids a copy for many cases, by handing you a pointer into
- * the memory-mapped database. It also locks the record to prevent
- * other accesses at the same time, so it won't change.
- *
- * Within the @parse callback you can perform read operations on the
- * database, but no write operations: no ntdb_store() or
- * ntdb_delete(), for example. The exception is if you call
- * ntdb_lockall() before ntdb_parse_record().
- *
- * Never alter the data handed to parse()!
- */
-#define ntdb_parse_record(ntdb, key, parse, data) \
- ntdb_parse_record_((ntdb), (key), \
- typesafe_cb_preargs(enum NTDB_ERROR, void *, \
- (parse), (data), \
- NTDB_DATA, NTDB_DATA), (data))
-
-enum NTDB_ERROR ntdb_parse_record_(struct ntdb_context *ntdb,
- NTDB_DATA key,
- enum NTDB_ERROR (*parse)(NTDB_DATA k,
- NTDB_DATA d,
- void *data),
- void *data);
-
-/**
- * ntdb_get_seqnum - get a database sequence number
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This returns a sequence number: any change to the database from a
- * ntdb context opened with the NTDB_SEQNUM flag will cause that number
- * to increment. Note that the incrementing is unreliable (it is done
- * without locking), so this is only useful as an optimization.
- *
- * For example, you may have a regular database backup routine which
- * does not operate if the sequence number is unchanged. In the
- * unlikely event of a failed increment, it will be backed up next
- * time any way.
- *
- * Returns an enum NTDB_ERROR (ie. negative) on error.
- */
-int64_t ntdb_get_seqnum(struct ntdb_context *ntdb);
-
-/**
- * ntdb_firstkey - get the "first" key in a NTDB
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: pointer to key.
- *
- * This returns an arbitrary key in the database; with ntdb_nextkey() it allows
- * open-coded traversal of the database, though it is slightly less efficient
- * than ntdb_traverse.
- *
- * It is your responsibility to free @key->dptr on success.
- *
- * Returns NTDB_ERR_NOEXIST if the database is empty.
- */
-enum NTDB_ERROR ntdb_firstkey(struct ntdb_context *ntdb, NTDB_DATA *key);
-
-/**
- * ntdb_nextkey - get the "next" key in a NTDB
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: a key returned by ntdb_firstkey() or ntdb_nextkey().
- *
- * This returns another key in the database; it will free @key.dptr for
- * your convenience.
- *
- * Returns NTDB_ERR_NOEXIST if there are no more keys.
- */
-enum NTDB_ERROR ntdb_nextkey(struct ntdb_context *ntdb, NTDB_DATA *key);
-
-/**
- * ntdb_chainlock - lock a record in the NTDB
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key to lock.
- *
- * This prevents any access occurring to a group of keys including @key,
- * even if @key does not exist. This allows primitive atomic updates of
- * records without using transactions.
- *
- * You cannot begin a transaction while holding a ntdb_chainlock(), nor can
- * you do any operations on any other keys in the database. This also means
- * that you cannot hold more than one ntdb_chainlock() at a time.
- *
- * See Also:
- * ntdb_chainunlock()
- */
-enum NTDB_ERROR ntdb_chainlock(struct ntdb_context *ntdb, NTDB_DATA key);
-
-/**
- * ntdb_chainunlock - unlock a record in the NTDB
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key to unlock.
- *
- * The key must have previously been locked by ntdb_chainlock().
- */
-void ntdb_chainunlock(struct ntdb_context *ntdb, NTDB_DATA key);
-
-/**
- * ntdb_chainlock_read - lock a record in the NTDB, for reading
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key to lock.
- *
- * This prevents any changes from occurring to a group of keys including @key,
- * even if @key does not exist. This allows primitive atomic updates of
- * records without using transactions.
- *
- * You cannot begin a transaction while holding a ntdb_chainlock_read(), nor can
- * you do any operations on any other keys in the database. This also means
- * that you cannot hold more than one ntdb_chainlock()/read() at a time.
- *
- * See Also:
- * ntdb_chainlock()
- */
-enum NTDB_ERROR ntdb_chainlock_read(struct ntdb_context *ntdb, NTDB_DATA key);
-
-/**
- * ntdb_chainunlock_read - unlock a record in the NTDB for reading
- * @ntdb: the ntdb context returned from ntdb_open()
- * @key: the key to unlock.
- *
- * The key must have previously been locked by ntdb_chainlock_read().
- */
-void ntdb_chainunlock_read(struct ntdb_context *ntdb, NTDB_DATA key);
-
-/**
- * ntdb_lockall - lock the entire NTDB
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * You cannot hold a ntdb_chainlock while calling this. It nests, so you
- * must call ntdb_unlockall as many times as you call ntdb_lockall.
- */
-enum NTDB_ERROR ntdb_lockall(struct ntdb_context *ntdb);
-
-/**
- * ntdb_unlockall - unlock the entire NTDB
- * @ntdb: the ntdb context returned from ntdb_open()
- */
-void ntdb_unlockall(struct ntdb_context *ntdb);
-
-/**
- * ntdb_lockall_read - lock the entire NTDB for reading
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This prevents others writing to the database, eg. ntdb_delete, ntdb_store,
- * ntdb_append, but not ntdb_fetch.
- *
- * You cannot hold a ntdb_chainlock while calling this. It nests, so you
- * must call ntdb_unlockall_read as many times as you call ntdb_lockall_read.
- */
-enum NTDB_ERROR ntdb_lockall_read(struct ntdb_context *ntdb);
-
-/**
- * ntdb_unlockall_read - unlock the entire NTDB for reading
- * @ntdb: the ntdb context returned from ntdb_open()
- */
-void ntdb_unlockall_read(struct ntdb_context *ntdb);
-
-/**
- * ntdb_wipe_all - wipe the database clean
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * Completely erase the database. This is faster than iterating through
- * each key and doing ntdb_delete.
- */
-enum NTDB_ERROR ntdb_wipe_all(struct ntdb_context *ntdb);
-
-/**
- * ntdb_repack - repack the database
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This repacks the database; if it is suffering from a great deal of
- * fragmentation this might help. However, it can take twice the
- * memory of the existing NTDB.
- */
-enum NTDB_ERROR ntdb_repack(struct ntdb_context *ntdb);
-
-/**
- * ntdb_check - check a NTDB for consistency
- * @ntdb: the ntdb context returned from ntdb_open()
- * @check: function to check each key/data pair (or NULL)
- * @data: argument for @check, must match type.
- *
- * This performs a consistency check of the open database, optionally calling
- * a check() function on each record so you can do your own data consistency
- * checks as well. If check() returns an error, that is returned from
- * ntdb_check().
- *
- * Note that the NTDB uses a feature which we don't understand which
- * indicates we can't run ntdb_check(), this will log a warning to that
- * effect and return NTDB_SUCCESS. You can detect this condition by
- * looking for NTDB_CANT_CHECK in ntdb_get_flags().
- *
- * Returns NTDB_SUCCESS or an error.
- */
-#define ntdb_check(ntdb, check, data) \
- ntdb_check_((ntdb), typesafe_cb_preargs(enum NTDB_ERROR, void *, \
- (check), (data), \
- NTDB_DATA, \
- NTDB_DATA), \
- (data))
-
-enum NTDB_ERROR ntdb_check_(struct ntdb_context *ntdb,
- enum NTDB_ERROR (*check)(NTDB_DATA k,
- NTDB_DATA d,
- void *data),
- void *data);
-
-/**
- * enum ntdb_summary_flags - flags for ntdb_summary.
- */
-enum ntdb_summary_flags {
- NTDB_SUMMARY_HISTOGRAMS = 1 /* Draw graphs in the summary. */
-};
-
-/**
- * ntdb_summary - return a string describing the NTDB state
- * @ntdb: the ntdb context returned from ntdb_open()
- * @flags: flags to control the summary output.
- * @summary: pointer to string to allocate.
- *
- * This returns a developer-readable string describing the overall
- * state of the ntdb, such as the percentage used and sizes of records.
- * It is designed to provide information about the ntdb at a glance
- * without displaying any keys or data in the database.
- *
- * On success, sets @summary to point to a malloc()'ed nul-terminated
- * multi-line string. It is your responsibility to free() it.
- */
-enum NTDB_ERROR ntdb_summary(struct ntdb_context *ntdb,
- enum ntdb_summary_flags flags,
- char **summary);
-
-
-/**
- * ntdb_get_flags - return the flags for a ntdb
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This returns the flags on the current ntdb. Some of these are caused by
- * the flags argument to ntdb_open(), others (such as NTDB_CONVERT) are
- * intuited.
- */
-unsigned int ntdb_get_flags(struct ntdb_context *ntdb);
-
-/**
- * ntdb_add_flag - set a flag for a ntdb
- * @ntdb: the ntdb context returned from ntdb_open()
- * @flag: one of NTDB_NOLOCK, NTDB_NOMMAP, NTDB_NOSYNC or NTDB_ALLOW_NESTING.
- *
- * You can use this to set a flag on the NTDB. You cannot set these flags
- * on a NTDB_INTERNAL ntdb.
- */
-void ntdb_add_flag(struct ntdb_context *ntdb, unsigned flag);
-
-/**
- * ntdb_remove_flag - unset a flag for a ntdb
- * @ntdb: the ntdb context returned from ntdb_open()
- * @flag: one of NTDB_NOLOCK, NTDB_NOMMAP, NTDB_NOSYNC or NTDB_ALLOW_NESTING.
- *
- * You can use this to clear a flag on the NTDB. You cannot clear flags
- * on a NTDB_INTERNAL ntdb.
- */
-void ntdb_remove_flag(struct ntdb_context *ntdb, unsigned flag);
-
-/**
- * enum ntdb_attribute_type - descriminator for union ntdb_attribute.
- */
-enum ntdb_attribute_type {
- NTDB_ATTRIBUTE_LOG = 0,
- NTDB_ATTRIBUTE_HASH = 1,
- NTDB_ATTRIBUTE_SEED = 2,
- NTDB_ATTRIBUTE_STATS = 3,
- NTDB_ATTRIBUTE_OPENHOOK = 4,
- NTDB_ATTRIBUTE_FLOCK = 5,
- NTDB_ATTRIBUTE_ALLOCATOR = 6,
- NTDB_ATTRIBUTE_HASHSIZE = 7
-};
-
-/**
- * ntdb_get_attribute - get an attribute for an existing ntdb
- * @ntdb: the ntdb context returned from ntdb_open()
- * @attr: the union ntdb_attribute to set.
- *
- * This gets an attribute from a NTDB which has previously been set (or
- * may return the default values). Set @attr.base.attr to the
- * attribute type you want get.
- */
-enum NTDB_ERROR ntdb_get_attribute(struct ntdb_context *ntdb,
- union ntdb_attribute *attr);
-
-/**
- * ntdb_set_attribute - set an attribute for an existing ntdb
- * @ntdb: the ntdb context returned from ntdb_open()
- * @attr: the union ntdb_attribute to set.
- *
- * This sets an attribute on a NTDB, overriding any previous attribute
- * of the same type. It returns NTDB_ERR_EINVAL if the attribute is
- * unknown or invalid.
- *
- * Note that NTDB_ATTRIBUTE_HASH, NTDB_ATTRIBUTE_SEED, and
- * NTDB_ATTRIBUTE_OPENHOOK cannot currently be set after ntdb_open.
- */
-enum NTDB_ERROR ntdb_set_attribute(struct ntdb_context *ntdb,
- const union ntdb_attribute *attr);
-
-/**
- * ntdb_unset_attribute - reset an attribute for an existing ntdb
- * @ntdb: the ntdb context returned from ntdb_open()
- * @type: the attribute type to unset.
- *
- * This unsets an attribute on a NTDB, returning it to the defaults
- * (where applicable).
- *
- * Note that it only makes sense for NTDB_ATTRIBUTE_LOG and NTDB_ATTRIBUTE_FLOCK
- * to be unset.
- */
-void ntdb_unset_attribute(struct ntdb_context *ntdb,
- enum ntdb_attribute_type type);
-
-/**
- * ntdb_name - get the name of a ntdb
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This returns a copy of the name string, made at ntdb_open() time.
- *
- * This is mostly useful for logging.
- */
-const char *ntdb_name(const struct ntdb_context *ntdb);
-
-/**
- * ntdb_fd - get the file descriptor of a ntdb
- * @ntdb: the ntdb context returned from ntdb_open()
- *
- * This returns the file descriptor for the underlying database file, or -1
- * for NTDB_INTERNAL.
- */
-int ntdb_fd(const struct ntdb_context *ntdb);
-
-/**
- * ntdb_foreach - iterate through every open NTDB.
- * @fn: the function to call for every NTDB
- * @p: the pointer to hand to @fn
- *
- * NTDB internally keeps track of all open TDBs; this function allows you to
- * iterate through them. If @fn returns non-zero, traversal stops.
- */
-#define ntdb_foreach(fn, p) \
- ntdb_foreach_(typesafe_cb_preargs(int, void *, (fn), (p), \
- struct ntdb_context *), (p))
-
-void ntdb_foreach_(int (*fn)(struct ntdb_context *, void *), void *p);
-
-/**
- * struct ntdb_attribute_base - common fields for all ntdb attributes.
- */
-struct ntdb_attribute_base {
- enum ntdb_attribute_type attr;
- union ntdb_attribute *next;
-};
-
-/**
- * enum ntdb_log_level - log levels for ntdb_attribute_log
- * @NTDB_LOG_ERROR: used to log unrecoverable errors such as I/O errors
- * or internal consistency failures.
- * @NTDB_LOG_USE_ERROR: used to log usage errors such as invalid parameters
- * or writing to a read-only database.
- * @NTDB_LOG_WARNING: used for informational messages on issues which
- * are unusual but handled by NTDB internally, such
- * as a failure to mmap or failure to open /dev/urandom.
- * It's also used when ntdb_open() fails without O_CREAT
- * because a file does not exist.
- */
-enum ntdb_log_level {
- NTDB_LOG_ERROR,
- NTDB_LOG_USE_ERROR,
- NTDB_LOG_WARNING
-};
-
-/**
- * struct ntdb_attribute_log - log function attribute
- *
- * This attribute provides a hook for you to log errors.
- */
-struct ntdb_attribute_log {
- struct ntdb_attribute_base base; /* .attr = NTDB_ATTRIBUTE_LOG */
- void (*fn)(struct ntdb_context *ntdb,
- enum ntdb_log_level level,
- enum NTDB_ERROR ecode,
- const char *message,
- void *data);
- void *data;
-};
-
-/**
- * struct ntdb_attribute_hash - hash function attribute
- *
- * This attribute allows you to provide an alternative hash function.
- * This hash function will be handed keys from the database; it will also
- * be handed the 8-byte NTDB_HASH_MAGIC value for checking the header (the
- * ntdb_open() will fail if the hash value doesn't match the header).
- *
- * Note that if your hash function gives different results on
- * different machine endians, your ntdb will no longer work across
- * different architectures!
- */
-struct ntdb_attribute_hash {
- struct ntdb_attribute_base base; /* .attr = NTDB_ATTRIBUTE_HASH */
- uint32_t (*fn)(const void *key, size_t len, uint32_t seed,
- void *data);
- void *data;
-};
-
-/**
- * struct ntdb_attribute_seed - hash function seed attribute
- *
- * The hash function seed is normally taken from /dev/urandom (or equivalent)
- * but can be set manually here. This is mainly for testing purposes.
- */
-struct ntdb_attribute_seed {
- struct ntdb_attribute_base base; /* .attr = NTDB_ATTRIBUTE_SEED */
- uint64_t seed;
-};
-
-/**
- * struct ntdb_attribute_stats - ntdb operational statistics
- *
- * This attribute records statistics of various low-level NTDB operations.
- * This can be used to assist performance evaluation. This is only
- * useful for ntdb_get_attribute().
- *
- * New fields will be added at the end, hence the "size" argument which
- * indicates how large your structure is: it must be filled in before
- * calling ntdb_get_attribute(), which will overwrite it with the size
- * ntdb knows about.
- */
-struct ntdb_attribute_stats {
- struct ntdb_attribute_base base; /* .attr = NTDB_ATTRIBUTE_STATS */
- size_t size; /* = sizeof(struct ntdb_attribute_stats) */
- uint64_t allocs;
- uint64_t alloc_subhash;
- uint64_t alloc_chain;
- uint64_t alloc_bucket_exact;
- uint64_t alloc_bucket_max;
- uint64_t alloc_leftover;
- uint64_t alloc_coalesce_tried;
- uint64_t alloc_coalesce_iterate_clash;
- uint64_t alloc_coalesce_lockfail;
- uint64_t alloc_coalesce_race;
- uint64_t alloc_coalesce_succeeded;
- uint64_t alloc_coalesce_num_merged;
- uint64_t compares;
- uint64_t compare_wrong_offsetbits;
- uint64_t compare_wrong_keylen;
- uint64_t compare_wrong_rechash;
- uint64_t compare_wrong_keycmp;
- uint64_t transactions;
- uint64_t transaction_cancel;
- uint64_t transaction_nest;
- uint64_t transaction_expand_file;
- uint64_t transaction_read_direct;
- uint64_t transaction_read_direct_fail;
- uint64_t transaction_write_direct;
- uint64_t transaction_write_direct_fail;
- uint64_t traverses;
- uint64_t traverse_val_vanished;
- uint64_t expands;
- uint64_t frees;
- uint64_t locks;
- uint64_t lock_lowlevel;
- uint64_t lock_nonblock;
- uint64_t lock_nonblock_fail;
-};
-
-/**
- * struct ntdb_attribute_openhook - ntdb special effects hook for open
- *
- * This attribute contains a function to call once we have the OPEN_LOCK
- * for the ntdb, but before we've examined its contents. If this succeeds,
- * the ntdb will be populated if it's then zero-length.
- *
- * This is a hack to allow support for TDB-style TDB_CLEAR_IF_FIRST
- * behaviour.
- */
-struct ntdb_attribute_openhook {
- struct ntdb_attribute_base base; /* .attr = NTDB_ATTRIBUTE_OPENHOOK */
- enum NTDB_ERROR (*fn)(int fd, void *data);
- void *data;
-};
-
-/**
- * struct ntdb_attribute_flock - ntdb special effects hook for file locking
- *
- * This attribute contains function to call to place locks on a file; it can
- * be used to support non-blocking operations or lock proxying.
- *
- * They should return 0 on success, -1 on failure and set errno.
- *
- * An error will be logged on error if errno is neither EAGAIN nor EINTR
- * (normally it would only return EAGAIN if waitflag is false, and
- * loop internally on EINTR).
- */
-struct ntdb_attribute_flock {
- struct ntdb_attribute_base base; /* .attr = NTDB_ATTRIBUTE_FLOCK */
- int (*lock)(int fd,int rw, off_t off, off_t len, bool waitflag, void *);
- int (*unlock)(int fd, int rw, off_t off, off_t len, void *);
- void *data;
-};
-
-/**
- * struct ntdb_attribute_hashsize - ntdb hashsize setting.
- *
- * This attribute is only settable on ntdb_open; it indicates that we create
- * a hashtable of the given size, rather than the default.
- */
-struct ntdb_attribute_hashsize {
- struct ntdb_attribute_base base; /* .attr = NTDB_ATTRIBUTE_HASHSIZE */
- uint32_t size;
-};
-
-/**
- * struct ntdb_attribute_allocator - allocator for ntdb to use.
- *
- * You can replace malloc/free with your own allocation functions.
- * The allocator takes an "owner" pointer, which is either NULL (for
- * the initial struct ntdb_context and struct ntdb_file), or a
- * previously allocated pointer. This is useful for relationship
- * tracking, such as the talloc library.
- *
- * The expand function is realloc, but only ever used to expand an
- * existing allocation.
- *
- * Be careful mixing allocators: two ntdb_contexts which have the same file
- * open will share the same struct ntdb_file. This may be allocated by one
- * ntdb's allocator, and freed by the other.
- */
-struct ntdb_attribute_allocator {
- struct ntdb_attribute_base base; /* .attr = NTDB_ATTRIBUTE_ALLOCATOR */
- void *(*alloc)(const void *owner, size_t len, void *priv_data);
- void *(*expand)(void *old, size_t newlen, void *priv_data);
- void (*free)(void *old, void *priv_data);
- void *priv_data;
-};
-
-/**
- * union ntdb_attribute - ntdb attributes.
- *
- * This represents all the known attributes.
- *
- * See also:
- * struct ntdb_attribute_log, struct ntdb_attribute_hash,
- * struct ntdb_attribute_seed, struct ntdb_attribute_stats,
- * struct ntdb_attribute_openhook, struct ntdb_attribute_flock,
- * struct ntdb_attribute_allocator alloc.
- */
-union ntdb_attribute {
- struct ntdb_attribute_base base;
- struct ntdb_attribute_log log;
- struct ntdb_attribute_hash hash;
- struct ntdb_attribute_seed seed;
- struct ntdb_attribute_stats stats;
- struct ntdb_attribute_openhook openhook;
- struct ntdb_attribute_flock flock;
- struct ntdb_attribute_allocator alloc;
- struct ntdb_attribute_hashsize hashsize;
-};
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* ntdb.h */
projects / ccan / blobdiff