source/tdb/tdb.h

   1 #ifndef __TDB_H__
   2 #define __TDB_H__
   3
   4 /*
   5    Unix SMB/Netbios implementation.
   6    Version 3.0
   7    Samba database functions
   8    Copyright (C) Andrew Tridgell 1999
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23 */
  24
  25 #ifdef  __cplusplus
  26 extern "C" {
  27 #endif
  28
  29
  30 /* flags to tdb_store() */
  31 #define TDB_REPLACE 1
  32 #define TDB_INSERT 2
  33 #define TDB_MODIFY 3
  34
  35 /* flags for tdb_open() */
  36 #define TDB_DEFAULT 0 /* just a readability place holder */
  37 #define TDB_CLEAR_IF_FIRST 1
  38 #define TDB_INTERNAL 2 /* don't store on disk */
  39 #define TDB_NOLOCK   4 /* don't do any locking */
  40 #define TDB_NOMMAP   8 /* don't use mmap */
  41 #define TDB_CONVERT 16 /* convert endian (internal use) */
  42
  43 #define TDB_ERRCODE(code, ret) ((tdb->ecode = (code)), ret)
  44
  45 /* error codes */
  46 enum TDB_ERROR {TDB_SUCCESS=0, TDB_ERR_CORRUPT, TDB_ERR_IO, TDB_ERR_LOCK,
  47                 TDB_ERR_OOM, TDB_ERR_EXISTS, TDB_ERR_NOEXIST, TDB_ERR_NOLOCK };
  48
  49 #ifndef u32
  50 #define u32 unsigned
  51 #endif
  52
  53 typedef struct {
  54         char *dptr;
  55         size_t dsize;
  56 } TDB_DATA;
  57
  58 typedef u32 tdb_len;
  59 typedef u32 tdb_off;
  60
  61 /* this is stored at the front of every database */
  62 struct tdb_header {
  63         char magic_food[32]; /* for /etc/magic */
  64         u32 version; /* version of the code */
  65         u32 hash_size; /* number of hash entries */
  66         tdb_off rwlocks;
  67         tdb_off reserved[31];
  68 };
  69
  70 struct tdb_lock_type {
  71         u32 count;
  72         u32 ltype;
  73 };
  74
  75 struct tdb_traverse_lock {
  76         struct tdb_traverse_lock *next;
  77         u32 off;
  78         u32 hash;
  79 };
  80
  81 /* this is the context structure that is returned from a db open */
  82 typedef struct tdb_context {
  83         char *name; /* the name of the database */
  84         void *map_ptr; /* where it is currently mapped */
  85         int fd; /* open file descriptor for the database */
  86         tdb_len map_size; /* how much space has been mapped */
  87         int read_only; /* opened read-only */
  88         struct tdb_lock_type *locked; /* array of chain locks */
  89         enum TDB_ERROR ecode; /* error code for last tdb error */
  90         struct tdb_header header; /* a cached copy of the header */
  91         u32 flags; /* the flags passed to tdb_open */
  92         u32 *lockedkeys; /* array of locked keys: first is #keys */
  93         struct tdb_traverse_lock travlocks; /* current traversal locks */
  94         struct tdb_context *next; /* all tdbs to avoid multiple opens */
  95         dev_t device;   /* uniquely identifies this tdb */
  96         ino_t inode;    /* uniquely identifies this tdb */
  97 } TDB_CONTEXT;
  98
  99 typedef int (*tdb_traverse_func)(TDB_CONTEXT *, TDB_DATA, TDB_DATA, void *);
 100
 101 TDB_CONTEXT *tdb_open(char *name, int hash_size, int tdb_flags,
 102                       int open_flags, mode_t mode);
 103 enum TDB_ERROR tdb_error(TDB_CONTEXT *tdb);
 104 const char *tdb_errorstr(TDB_CONTEXT *tdb);
 105 TDB_DATA tdb_fetch(TDB_CONTEXT *tdb, TDB_DATA key);
 106 int tdb_delete(TDB_CONTEXT *tdb, TDB_DATA key);
 107 int tdb_store(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, int flag);
 108 int tdb_close(TDB_CONTEXT *tdb);
 109 TDB_DATA tdb_firstkey(TDB_CONTEXT *tdb);
 110 TDB_DATA tdb_nextkey(TDB_CONTEXT *tdb, TDB_DATA key);
 111 int tdb_traverse(TDB_CONTEXT *tdb, tdb_traverse_func fn, void *state);
 112 int tdb_exists(TDB_CONTEXT *tdb, TDB_DATA key);
 113 int tdb_lockkeys(TDB_CONTEXT *tdb, u32 number, TDB_DATA keys[]);
 114 void tdb_unlockkeys(TDB_CONTEXT *tdb);
 115 int tdb_lockall(TDB_CONTEXT *tdb);
 116 void tdb_unlockall(TDB_CONTEXT *tdb);
 117
 118 /* Low level locking functions: use with care */
 119 int tdb_chainlock(TDB_CONTEXT *tdb, TDB_DATA key);
 120 void tdb_chainunlock(TDB_CONTEXT *tdb, TDB_DATA key);
 121 extern TDB_DATA tdb_null;
 122 #ifdef  __cplusplus
 123 }
 124 #endif
 125
 126 #endif /* tdb.h */