// assumes that env != null and txp != null!
internal void Initialize(DB_TXN* txp) {
this.txp = txp;
txp->api_internal = (IntPtr)instanceHandle;
}
Int64 Get(DB_TXN* txp, Int32 delta, ReadFlags flags) {
Int64 value;
DbRetVal ret;
lock (rscLock) {
DB_SEQUENCE* seqp = CheckDisposed();
if (SeqGet == null)
throw new BdbException("Sequence must be open.");
ret = SeqGet(seqp, txp, delta, out value, unchecked((UInt32)flags));
}
Util.CheckRetVal(ret);
return value;
}
DbRetVal Remove(DB_TXN* txp, RemoveFlags flags) {
DbRetVal ret;
// always lock Db first, to avoid deadlock
lock (db.rscLock) {
lock (rscLock) {
RuntimeHelpers.PrepareConstrainedRegions();
try { }
finally {
DB_SEQUENCE* seqp = CheckDisposed();
// DB_SEQUENCE->Remove() could be a lengthy call, so we call Disposed() first, and the
// CER ensures that we reach DB_SEQUENCE->Remove() without external interruption.
// This is OK because one must not use the handle after DB_SEQUENCE->Remove() was called,
// regardless of the return value.
Disposed();
ret = seqp->Remove(seqp, txp, unchecked((UInt32)flags));
}
}
}
return ret;
}
DbRetVal Open(DB_TXN* txp, ref DbEntry key, OpenFlags flags) {
DbRetVal ret;
lock (rscLock) {
DB_SEQUENCE* seqp = CheckDisposed();
fixed (byte* keyBufP = key.Buffer) {
key.dbt.data = keyBufP + key.Start;
ret = seqp->Open(seqp, txp, ref key.dbt, unchecked((UInt32)flags));
}
// initialize function pointer delegates
SeqGet = seqp->Get;
}
return ret;
}
void* GetPage(ref uint pageNo, DB_TXN* txp, CachePageGetFlags flags) {
DbRetVal ret;
void* page;
lock (rscLock) {
DB_MPOOLFILE* mpf = CheckDisposed();
ret = mpf->Get(mpf, ref pageNo, txp, flags, out page);
}
Util.CheckRetVal(ret);
return page;
}
void LogPrintFile(DB_TXN* txp, byte[] msg) {
DbRetVal ret;
lock (rscLock) {
DB_ENV* evp = CheckDisposed();
fixed (byte* msgPtr = msg) {
ret = evp->LogPrintFile(evp, txp, msgPtr);
}
}
Util.CheckRetVal(ret);
}
// must be called under an environment and parent lock
DbRetVal TxnBegin(DB_TXN* parxp, Txn txn, Txn.BeginFlags flags) {
DbRetVal ret;
RuntimeHelpers.PrepareConstrainedRegions();
try { }
finally {
DB_TXN* txp;
DB_ENV* evp = CheckDisposed();
ret = evp->TxnBegin(evp, parxp, out txp, unchecked((UInt32)flags));
if (ret == DbRetVal.SUCCESS) {
txn.Initialize(txp);
transactions.Insert(txn);
}
}
return ret;
}
DbRetVal DbRename(DB_TXN* txp, byte[] fBytes, byte[] dBytes, byte[] nBytes, WriteFlags flags) {
DB_ENV* evp = CheckDisposed();
fixed (byte* fp = fBytes, dp = dBytes, np = nBytes) {
return evp->DbRename(evp, txp, fp, dp, np, unchecked((UInt32)flags));
}
}