pppd/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 #ifndef PRINTF_ATTRIBUTE
  35 /** Use gcc attribute to check printf fns.  a1 is the 1-based index of
  36  * the parameter containing the format, and a2 the index of the first
  37  * argument. Note that some gcc 2.x versions don't handle this
  38  * properly **/
  39 #if (__GNUC__ >= 3)
  40 #define PRINTF_ATTRIBUTE(a1, a2) __attribute__ ((format (__printf__, a1, a2)))
  41 #else
  42 #define PRINTF_ATTRIBUTE(a1, a2)
  43 #endif
  44 #endif
  45
  46 /* flags to tdb_store() */
  47 #define TDB_REPLACE 1
  48 #define TDB_INSERT 2
  49 #define TDB_MODIFY 3
  50
  51 /* flags for tdb_open() */
  52 #define TDB_DEFAULT 0 /* just a readability place holder */
  53 #define TDB_CLEAR_IF_FIRST 1
  54 #define TDB_INTERNAL 2 /* don't store on disk */
  55 #define TDB_NOLOCK   4 /* don't do any locking */
  56 #define TDB_NOMMAP   8 /* don't use mmap */
  57 #define TDB_CONVERT 16 /* convert endian (internal use) */
  58 #define TDB_BIGENDIAN 32 /* header is big-endian (internal use) */
  59
  60 #define TDB_ERRCODE(code, ret) ((tdb->ecode = (code)), ret)
  61
  62 /* error codes */
  63 enum TDB_ERROR {TDB_SUCCESS=0, TDB_ERR_CORRUPT, TDB_ERR_IO, TDB_ERR_LOCK,
  64                 TDB_ERR_OOM, TDB_ERR_EXISTS, TDB_ERR_NOLOCK, TDB_ERR_LOCK_TIMEOUT,
  65                 TDB_ERR_NOEXIST};
  66
  67 #ifndef u32
  68 #define u32 unsigned
  69 #endif
  70
  71 typedef struct {
  72         char *dptr;
  73         size_t dsize;
  74 } TDB_DATA;
  75
  76 typedef u32 tdb_len;
  77 typedef u32 tdb_off;
  78
  79 /* this is stored at the front of every database */
  80 struct tdb_header {
  81         char magic_food[32]; /* for /etc/magic */
  82         u32 version; /* version of the code */
  83         u32 hash_size; /* number of hash entries */
  84         tdb_off rwlocks;
  85         tdb_off reserved[31];
  86 };
  87
  88 struct tdb_lock_type {
  89         u32 count;
  90         u32 ltype;
  91 };
  92
  93 struct tdb_traverse_lock {
  94         struct tdb_traverse_lock *next;
  95         u32 off;
  96         u32 hash;
  97 };
  98
  99 /* this is the context structure that is returned from a db open */
 100 typedef struct tdb_context {
 101         char *name; /* the name of the database */
 102         void *map_ptr; /* where it is currently mapped */
 103         int fd; /* open file descriptor for the database */
 104         tdb_len map_size; /* how much space has been mapped */
 105         int read_only; /* opened read-only */
 106         struct tdb_lock_type *locked; /* array of chain locks */
 107         enum TDB_ERROR ecode; /* error code for last tdb error */
 108         struct tdb_header header; /* a cached copy of the header */
 109         u32 flags; /* the flags passed to tdb_open */
 110         struct tdb_traverse_lock travlocks; /* current traversal locks */
 111         struct tdb_context *next; /* all tdbs to avoid multiple opens */
 112         dev_t device;   /* uniquely identifies this tdb */
 113         ino_t inode;    /* uniquely identifies this tdb */
 114         void (*log_fn)(struct tdb_context *tdb, int level, const char *, ...) PRINTF_ATTRIBUTE(3,4); /* logging function */
 115         u32 (*hash_fn)(TDB_DATA *key);
 116         int open_flags; /* flags used in the open - needed by reopen */
 117 } TDB_CONTEXT;
 118
 119 typedef int (*tdb_traverse_func)(TDB_CONTEXT *, TDB_DATA, TDB_DATA, void *);
 120 typedef void (*tdb_log_func)(TDB_CONTEXT *, int , const char *, ...);
 121 typedef u32 (*tdb_hash_func)(TDB_DATA *key);
 122
 123 TDB_CONTEXT *tdb_open(const char *name, int hash_size, int tdb_flags,
 124                       int open_flags, mode_t mode);
 125 TDB_CONTEXT *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
 126                          int open_flags, mode_t mode,
 127                          tdb_log_func log_fn,
 128                          tdb_hash_func hash_fn);
 129
 130 int tdb_reopen(TDB_CONTEXT *tdb);
 131 int tdb_reopen_all(void);
 132 void tdb_logging_function(TDB_CONTEXT *tdb, tdb_log_func);
 133 enum TDB_ERROR tdb_error(TDB_CONTEXT *tdb);
 134 const char *tdb_errorstr(TDB_CONTEXT *tdb);
 135 TDB_DATA tdb_fetch(TDB_CONTEXT *tdb, TDB_DATA key);
 136 int tdb_delete(TDB_CONTEXT *tdb, TDB_DATA key);
 137 int tdb_store(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, int flag);
 138 int tdb_append(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA new_dbuf);
 139 int tdb_close(TDB_CONTEXT *tdb);
 140 TDB_DATA tdb_firstkey(TDB_CONTEXT *tdb);
 141 TDB_DATA tdb_nextkey(TDB_CONTEXT *tdb, TDB_DATA key);
 142 int tdb_traverse(TDB_CONTEXT *tdb, tdb_traverse_func fn, void *);
 143 int tdb_exists(TDB_CONTEXT *tdb, TDB_DATA key);
 144 int tdb_lockkeys(TDB_CONTEXT *tdb, u32 number, TDB_DATA keys[]);
 145 void tdb_unlockkeys(TDB_CONTEXT *tdb);
 146 int tdb_lockall(TDB_CONTEXT *tdb);
 147 void tdb_unlockall(TDB_CONTEXT *tdb);
 148
 149 /* Low level locking functions: use with care */
 150 void tdb_set_lock_alarm(sig_atomic_t *palarm);
 151 int tdb_chainlock(TDB_CONTEXT *tdb, TDB_DATA key);
 152 int tdb_chainunlock(TDB_CONTEXT *tdb, TDB_DATA key);
 153
 154 /* Debug functions. Not used in production. */
 155 void tdb_dump_all(TDB_CONTEXT *tdb);
 156 int tdb_printfreelist(TDB_CONTEXT *tdb);
 157
 158 extern TDB_DATA tdb_null;
 159
 160 #ifdef  __cplusplus
 161 }
 162 #endif
 163
 164 #endif /* tdb.h */