// assumes that env != null
internal LogCursor(Env env) {
this.env = env;
}
internal Txn(Env env) {
this.env = env;
// so that we can refer back to the Txn instance
instanceHandle = GCHandle.Alloc(this, GCHandleType.WeakTrackResurrection);
}
/// <summary>
/// ��ʼ��
/// </summary>
private void Init()
{
env = new Env(EnvCreateFlags.None);
Env.OpenFlags envFlags =
Env.OpenFlags.Create |
Env.OpenFlags.InitLock |
Env.OpenFlags.InitLog |
Env.OpenFlags.InitMPool |
Env.OpenFlags.InitTxn |
Env.OpenFlags.Recover;
env.Open(directory, envFlags, 0);
txn = env.TxnBegin(null, Txn.BeginFlags.None);
db = env.CreateDatabase(DbCreateFlags.None);
btree = (DbHash)db.Open(txn, dbName, null, DbType.Hash, Db.OpenFlags.Create, 0);
}
internal EnvCacheFile(Env env): base(new object()) {
this.env = env;
}
static CallbackStatus PageInOutWrapCLS(Env env, UInt32 pgno, void* pgaddr, ref DBT pgcookie, PageInOutFcn pgInOut) {
// construct DbEntry for pgcookie
int size = unchecked((int)pgcookie.size);
// we are not using a shared buffer - the call-back might take
// a long time and we do not want to lock the buffer that long
byte[] buffer = new byte[size];
Marshal.Copy((IntPtr)pgcookie.data, buffer, 0, size);
DbEntry cookieEntry = DbEntry.InOut(buffer, 0, size);
cookieEntry.dbt.flags = pgcookie.flags;
cookieEntry.dbt.dlen = pgcookie.dlen;
cookieEntry.dbt.doff = pgcookie.doff;
// call CLS compliant delegate - we assume it is not null
return pgInOut(env, new CachePage(pgno, (IntPtr)pgaddr), ref cookieEntry);
}
static CallbackStatus PageInOutWrapCLS(Env env, UInt32 pgno, void* pgaddr, ref DBT pgcookie, PageInOutFcn pgInOut) {
IntPtr cookie = IntPtr.Zero;
// extract IntPtr from DBT
int size = unchecked((int)pgcookie.size);
if (size != 0) {
if (size != sizeof(IntPtr))
throw new BdbException("Invalid page cookie.");
cookie = *(IntPtr*)pgcookie.data;
}
// call CLS compliant delegate - we assume it is not null
return pgInOut(env, new CachePage(pgno, (IntPtr)pgaddr), cookie);
}