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diff --git a/lib/tdb/common/tdb_private.h b/lib/tdb/common/tdb_private.h
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+#ifndef TDB_PRIVATE_H
+#define TDB_PRIVATE_H
+ /*
+ 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"
+
+/* #define TDB_TRACE 1 */
+#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_RECOVERY_INVALID_MAGIC (0x0)
+#define TDB_HASH_RWLOCK_MAGIC (0xbad1a51U)
+#define TDB_FEATURE_FLAG_MAGIC (0xbad1a52U)
+#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->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
+
+#define TDB_FEATURE_FLAG_MUTEX 0x00000001
+
+#define TDB_SUPPORTED_FEATURE_FLAGS ( \
+ TDB_FEATURE_FLAG_MUTEX | \
+ 0)
+
+/* 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
+
+#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_1plusn_rec_flag_ret(struct tdb_context *tdb, const char *op,
+ TDB_DATA rec,
+ const TDB_DATA *recs, int num_recs,
+ 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_1plusn_rec_flag_ret(tdb, op, rec, recs, num_recs, flag, ret);
+#define tdb_trace_2rec_retrec(tdb, op, rec1, rec2, ret)
+#endif /* !TDB_TRACE */
+
+/* lock offsets */
+#define OPEN_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
+
+/*
+ * Note: the BUCKET macro is broken as it returns an unexpected result when
+ * called as BUCKET(-1) for the freelist:
+ *
+ * -1 is sign converted to an unsigned int 4294967295 and then the modulo
+ * tdb->hashtable_size is computed. So with a hashtable_size of 10 the result
+ * is
+ *
+ * 4294967295 % hashtable_size = 5.
+ *
+ * where it should be -1 (C uses symmetric modulo).
+ *
+ * As all callers will lock the same wrong list consistently locking is still
+ * consistent. We can not change this without an incompatible on-disk format
+ * change, otherwise different tdb versions would use incompatible locking.
+ */
+#define BUCKET(hash) ((hash) % tdb->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 tdb_record for the free space
+ plus a separate data list for each hash value */
+struct tdb_record {
+ 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 */
+ uint32_t magic1_hash; /* hash of TDB_MAGIC_FOOD. */
+ uint32_t magic2_hash; /* hash of TDB_MAGIC. */
+ uint32_t feature_flags;
+ tdb_len_t mutex_size; /* set if TDB_FEATURE_FLAG_MUTEX is set */
+ tdb_off_t reserved[25];
+};
+
+struct tdb_lock_type {
+ uint32_t off;
+ uint32_t count;
+ uint32_t ltype;
+};
+
+struct tdb_chainwalk_ctx {
+ tdb_off_t slow_ptr;
+ bool slow_chase;
+};
+
+struct tdb_traverse_lock {
+ struct tdb_traverse_lock *next;
+ uint32_t off;
+ uint32_t list;
+ int lock_rw;
+};
+
+void tdb_chainwalk_init(struct tdb_chainwalk_ctx *ctx, tdb_off_t ptr);
+bool tdb_chainwalk_check(struct tdb_context *tdb,
+ struct tdb_chainwalk_ctx *ctx,
+ tdb_off_t next_ptr);
+
+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 actually lock at all. */
+ TDB_LOCK_MARK_ONLY = 4,
+};
+
+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 , tdb_len_t, int );
+ int (*tdb_expand_file)(struct tdb_context *, tdb_off_t , tdb_off_t );
+};
+
+struct tdb_mutexes;
+
+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 allrecord_lock; /* .offset == upgradable */
+ int num_lockrecs;
+ struct tdb_lock_type *lockrecs; /* only real locks, all with count>0 */
+ int lockrecs_array_length;
+
+ tdb_off_t hdr_ofs; /* this is 0 or header.mutex_size */
+ struct tdb_mutexes *mutexes; /* mmap of the mutex area */
+
+ enum TDB_ERROR ecode; /* error code for last tdb error */
+ uint32_t hash_size;
+ uint32_t feature_flags;
+ 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 */
+ const struct tdb_methods *methods;
+ struct tdb_transaction *transaction;
+ int page_size;
+ int max_dead_records;
+#ifdef TDB_TRACE
+ int tracefd;
+#endif
+ volatile sig_atomic_t *interrupt_sig_ptr;
+};
+
+
+/*
+ internal prototypes
+*/
+int tdb_munmap(struct tdb_context *tdb);
+int 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_nest_lock(struct tdb_context *tdb, uint32_t offset, int ltype,
+ enum tdb_lock_flags flags);
+int tdb_nest_unlock(struct tdb_context *tdb, uint32_t offset, int ltype,
+ bool mark_lock);
+int tdb_unlock(struct tdb_context *tdb, int list, int ltype);
+int tdb_brlock(struct tdb_context *tdb,
+ int rw_type, tdb_off_t offset, size_t len,
+ enum tdb_lock_flags flags);
+int tdb_brunlock(struct tdb_context *tdb,
+ int rw_type, tdb_off_t offset, size_t len);
+bool tdb_have_extra_locks(struct tdb_context *tdb);
+void tdb_release_transaction_locks(struct tdb_context *tdb);
+int tdb_transaction_lock(struct tdb_context *tdb, int ltype,
+ enum tdb_lock_flags lockflags);
+int tdb_transaction_unlock(struct tdb_context *tdb, int ltype);
+int tdb_recovery_area(struct tdb_context *tdb,
+ const struct tdb_methods *methods,
+ tdb_off_t *recovery_offset,
+ struct tdb_record *rec);
+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, bool mark_lock);
+int tdb_allrecord_upgrade(struct tdb_context *tdb);
+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 tdb_record *rec);
+tdb_off_t tdb_allocate(struct tdb_context *tdb, int hash, tdb_len_t length,
+ struct tdb_record *rec);
+
+int _tdb_oob(struct tdb_context *tdb, tdb_off_t off, tdb_len_t len, int probe);
+
+static inline int tdb_oob(
+ struct tdb_context *tdb, tdb_off_t off, tdb_len_t len, int probe)
+{
+ if (likely((off + len >= off) && (off + len <= tdb->map_size))) {
+ return 0;
+ }
+ return _tdb_oob(tdb, off, len, probe);
+}
+
+
+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);
+bool tdb_needs_recovery(struct tdb_context *tdb);
+int tdb_rec_read(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec);
+int tdb_rec_write(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *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 tdb_record *rec);
+tdb_off_t tdb_find_dead(struct tdb_context *tdb, uint32_t hash,
+ struct tdb_record *r, tdb_len_t length,
+ tdb_off_t *p_last_ptr);
+int tdb_trim_dead(struct tdb_context *tdb, uint32_t hash);
+void tdb_io_init(struct tdb_context *tdb);
+int tdb_expand(struct tdb_context *tdb, tdb_off_t size);
+tdb_off_t tdb_expand_adjust(tdb_off_t map_size, tdb_off_t size, int page_size);
+int tdb_rec_free_read(struct tdb_context *tdb, tdb_off_t off,
+ struct tdb_record *rec);
+bool tdb_write_all(int fd, const void *buf, size_t count);
+int tdb_transaction_recover(struct tdb_context *tdb);
+void tdb_header_hash(struct tdb_context *tdb,
+ uint32_t *magic1_hash, uint32_t *magic2_hash);
+unsigned int tdb_old_hash(TDB_DATA *key);
+size_t tdb_dead_space(struct tdb_context *tdb, tdb_off_t off);
+bool tdb_add_off_t(tdb_off_t a, tdb_off_t b, tdb_off_t *pret);
+
+/* tdb_off_t and tdb_len_t right now are both uint32_t */
+#define tdb_add_len_t tdb_add_off_t
+
+size_t tdb_mutex_size(struct tdb_context *tdb);
+bool tdb_have_mutexes(struct tdb_context *tdb);
+int tdb_mutex_init(struct tdb_context *tdb);
+int tdb_mutex_mmap(struct tdb_context *tdb);
+int tdb_mutex_munmap(struct tdb_context *tdb);
+bool tdb_mutex_lock(struct tdb_context *tdb, int rw, off_t off, off_t len,
+ bool waitflag, int *pret);
+bool tdb_mutex_unlock(struct tdb_context *tdb, int rw, off_t off, off_t len,
+ int *pret);
+int tdb_mutex_allrecord_lock(struct tdb_context *tdb, int ltype,
+ enum tdb_lock_flags flags);
+int tdb_mutex_allrecord_unlock(struct tdb_context *tdb);
+int tdb_mutex_allrecord_upgrade(struct tdb_context *tdb);
+void tdb_mutex_allrecord_downgrade(struct tdb_context *tdb);
+
+#endif /* TDB_PRIVATE_H */