source3/tdb/tdb.h

   1 #ifndef __TDB_H__
   2 #define __TDB_H__
   3
   4 /*
   5    Unix SMB/CIFS implementation.
   6
   7    trivial database library
   8
   9    Copyright (C) Andrew Tridgell 1999-2004
  10
  11      ** NOTE! The following LGPL license applies to the tdb
  12      ** library. This does NOT imply that all of Samba is released
  13      ** under the LGPL
  14
  15    This library is free software; you can redistribute it and/or
  16    modify it under the terms of the GNU Lesser General Public
  17    License as published by the Free Software Foundation; either
  18    version 2 of the License, or (at your option) any later version.
  19
  20    This library is distributed in the hope that it will be useful,
  21    but WITHOUT ANY WARRANTY; without even the implied warranty of
  22    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  23    Lesser General Public License for more details.
  24
  25    You should have received a copy of the GNU Lesser General Public
  26    License along with this library; if not, write to the Free Software
  27    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  28 */
  29
  30 #ifdef  __cplusplus
  31 extern "C" {
  32 #endif
  33
  34
  35 /* flags to tdb_store() */
  36 #define TDB_REPLACE 1
  37 #define TDB_INSERT 2
  38 #define TDB_MODIFY 3
  39
  40 /* flags for tdb_open() */
  41 #define TDB_DEFAULT 0 /* just a readability place holder */
  42 #define TDB_CLEAR_IF_FIRST 1
  43 #define TDB_INTERNAL 2 /* don't store on disk */
  44 #define TDB_NOLOCK   4 /* don't do any locking */
  45 #define TDB_NOMMAP   8 /* don't use mmap */
  46 #define TDB_CONVERT 16 /* convert endian (internal use) */
  47 #define TDB_BIGENDIAN 32 /* header is big-endian (internal use) */
  48
  49 #define TDB_ERRCODE(code, ret) ((tdb->ecode = (code)), ret)
  50
  51 /* error codes */
  52 enum TDB_ERROR {TDB_SUCCESS=0, TDB_ERR_CORRUPT, TDB_ERR_IO, TDB_ERR_LOCK,
  53                 TDB_ERR_OOM, TDB_ERR_EXISTS, TDB_ERR_NOLOCK, TDB_ERR_LOCK_TIMEOUT,
  54                 TDB_ERR_NOEXIST};
  55
  56 #ifndef u32
  57 #define u32 unsigned
  58 #endif
  59
  60 typedef struct {
  61         char *dptr;
  62         size_t dsize;
  63 } TDB_DATA;
  64
  65 typedef u32 tdb_len;
  66 typedef u32 tdb_off;
  67
  68 /* this is stored at the front of every database */
  69 struct tdb_header {
  70         char magic_food[32]; /* for /etc/magic */
  71         u32 version; /* version of the code */
  72         u32 hash_size; /* number of hash entries */
  73         tdb_off rwlocks;
  74         tdb_off reserved[31];
  75 };
  76
  77 struct tdb_lock_type {
  78         u32 count;
  79         u32 ltype;
  80 };
  81
  82 struct tdb_traverse_lock {
  83         struct tdb_traverse_lock *next;
  84         u32 off;
  85         u32 hash;
  86 };
  87
  88 /* this is the context structure that is returned from a db open */
  89 typedef struct tdb_context {
  90         char *name; /* the name of the database */
  91         void *map_ptr; /* where it is currently mapped */
  92         int fd; /* open file descriptor for the database */
  93         tdb_len map_size; /* how much space has been mapped */
  94         int read_only; /* opened read-only */
  95         struct tdb_lock_type *locked; /* array of chain locks */
  96         enum TDB_ERROR ecode; /* error code for last tdb error */
  97         struct tdb_header header; /* a cached copy of the header */
  98         u32 flags; /* the flags passed to tdb_open */
  99         u32 *lockedkeys; /* array of locked keys: first is #keys */
 100         struct tdb_traverse_lock travlocks; /* current traversal locks */
 101         struct tdb_context *next; /* all tdbs to avoid multiple opens */
 102         dev_t device;   /* uniquely identifies this tdb */
 103         ino_t inode;    /* uniquely identifies this tdb */
 104         void (*log_fn)(struct tdb_context *tdb, int level, const char *, ...); /* logging function */
 105         int open_flags; /* flags used in the open - needed by reopen */
 106 } TDB_CONTEXT;
 107
 108 typedef int (*tdb_traverse_func)(TDB_CONTEXT *, TDB_DATA, TDB_DATA, void *);
 109 typedef void (*tdb_log_func)(TDB_CONTEXT *, int , const char *, ...);
 110
 111 TDB_CONTEXT *tdb_open(const char *name, int hash_size, int tdb_flags,
 112                       int open_flags, mode_t mode);
 113 TDB_CONTEXT *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
 114                          int open_flags, mode_t mode,
 115                          tdb_log_func log_fn);
 116
 117 int tdb_reopen(TDB_CONTEXT *tdb);
 118 int tdb_reopen_all(void);
 119 void tdb_logging_function(TDB_CONTEXT *tdb, tdb_log_func);
 120 enum TDB_ERROR tdb_error(TDB_CONTEXT *tdb);
 121 const char *tdb_errorstr(TDB_CONTEXT *tdb);
 122 TDB_DATA tdb_fetch(TDB_CONTEXT *tdb, TDB_DATA key);
 123 int tdb_delete(TDB_CONTEXT *tdb, TDB_DATA key);
 124 int tdb_store(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, int flag);
 125 int tdb_append(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA new_dbuf);
 126 int tdb_close(TDB_CONTEXT *tdb);
 127 TDB_DATA tdb_firstkey(TDB_CONTEXT *tdb);
 128 TDB_DATA tdb_nextkey(TDB_CONTEXT *tdb, TDB_DATA key);
 129 int tdb_traverse(TDB_CONTEXT *tdb, tdb_traverse_func fn, void *);
 130 int tdb_exists(TDB_CONTEXT *tdb, TDB_DATA key);
 131 int tdb_lockkeys(TDB_CONTEXT *tdb, u32 number, TDB_DATA keys[]);
 132 void tdb_unlockkeys(TDB_CONTEXT *tdb);
 133 int tdb_lockall(TDB_CONTEXT *tdb);
 134 void tdb_unlockall(TDB_CONTEXT *tdb);
 135
 136 /* Low level locking functions: use with care */
 137 void tdb_set_lock_alarm(sig_atomic_t *palarm);
 138 int tdb_chainlock(TDB_CONTEXT *tdb, TDB_DATA key);
 139 int tdb_chainunlock(TDB_CONTEXT *tdb, TDB_DATA key);
 140
 141 /* Debug functions. Not used in production. */
 142 void tdb_dump_all(TDB_CONTEXT *tdb);
 143 int tdb_printfreelist(TDB_CONTEXT *tdb);
 144
 145 extern TDB_DATA tdb_null;
 146
 147 #ifdef  __cplusplus
 148 }
 149 #endif
 150
 151 #endif /* tdb.h */