--- /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