Lightning Memory-Mapped Database (LMDB) backend for the key/value Store. More...

#include "config.h"
#include <stddef.h>
#include <lmdb.h>
#include <stdint.h>
#include "mutt/lib.h"
#include "lib.h"

Include dependency graph for lmdb.c:

Go to the source code of this file.

Data Structures
struct	StoreLmdbCtx
	LMDB context. More...

Enumerations
enum	MdbTxnMode { TXN_UNINITIALIZED , TXN_READ , TXN_WRITE }
	The maximum size of the database file (2GiB). More...

Functions
static int	mdb_get_r_txn (struct StoreLmdbCtx *ctx)
	Get an LMDB read transaction. More...

static int	mdb_get_w_txn (struct StoreLmdbCtx *ctx)
	Get an LMDB write transaction. More...

static void *	store_lmdb_open (const char *path)
	Implements StoreOps::open() -. More...

static void *	store_lmdb_fetch (void store, const char key, size_t klen, size_t *vlen)
	Implements StoreOps::fetch() -. More...

static void	store_lmdb_free (void store, void *ptr)
	Implements StoreOps::free() -. More...

static int	store_lmdb_store (void store, const char key, size_t klen, void *value, size_t vlen)
	Implements StoreOps::store() -. More...

static int	store_lmdb_delete_record (void store, const char key, size_t klen)
	Implements StoreOps::delete_record() -. More...

static void	store_lmdb_close (void **ptr)
	Implements StoreOps::close() -. More...

static const char *	store_lmdb_version (void)
	Implements StoreOps::version() -. More...

Detailed Description

Lightning Memory-Mapped Database (LMDB) backend for the key/value Store.

Authors

Thomas Glanzmann
Tobias Werth
Brian Fundakowski Feldman
Pietro Cerutti

Copyright: This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version.

This program 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 General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Definition in file lmdb.c.

Enumeration Type Documentation

◆ MdbTxnMode

enum MdbTxnMode

The maximum size of the database file (2GiB).

The file is mmap(2)'d into memory. LMDB transaction state

Enumerator
TXN_UNINITIALIZED	Transaction is uninitialised.
TXN_READ	Read transaction in progress.
TXN_WRITE	Write transaction in progress.

Definition at line 55 of file lmdb.c.

 {
   TXN_UNINITIALIZED, 
   TXN_READ,          
   TXN_WRITE,         
 };

Function Documentation

◆ mdb_get_r_txn()

static int mdb_get_r_txn ( struct StoreLmdbCtx * ctx )

static

Get an LMDB read transaction.

Parameters

ctx	LMDB context

Return values

num	LMDB return code, e.g. MDB_SUCCESS

Definition at line 78 of file lmdb.c.

 {
   int rc;
  
   if (ctx->txn && ((ctx->txn_mode == TXN_READ) || (ctx->txn_mode == TXN_WRITE)))
     return MDB_SUCCESS;
  
   if (ctx->txn)
     rc = mdb_txn_renew(ctx->txn);
   else
     rc = mdb_txn_begin(ctx->env, NULL, MDB_RDONLY, &ctx->txn);
  
   if (rc == MDB_SUCCESS)
     ctx->txn_mode = TXN_READ;
   else
   {
     mutt_debug(LL_DEBUG2, "%s: %s\n",
                ctx->txn ? "mdb_txn_renew" : "mdb_txn_begin", mdb_strerror(rc));
   }
  
   return rc;
 }

Here is the caller graph for this function:

◆ mdb_get_w_txn()

static int mdb_get_w_txn ( struct StoreLmdbCtx * ctx )

static

Get an LMDB write transaction.

Parameters

ctx	LMDB context

Return values

num	LMDB return code, e.g. MDB_SUCCESS

Definition at line 106 of file lmdb.c.

 {
   int rc;
  
   if (ctx->txn)
   {
     if (ctx->txn_mode == TXN_WRITE)
       return MDB_SUCCESS;
  
     /* Free up the memory for readonly or reset transactions */
     mdb_txn_abort(ctx->txn);
   }
  
   rc = mdb_txn_begin(ctx->env, NULL, 0, &ctx->txn);
   if (rc == MDB_SUCCESS)
     ctx->txn_mode = TXN_WRITE;
   else
     mutt_debug(LL_DEBUG2, "mdb_txn_begin: %s\n", mdb_strerror(rc));
  
   return rc;
 }