/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1998-2002 * Sleepycat Software. All rights reserved. */ #include "db_config.h" #ifndef lint static const char revid[] = "$Id: xa.c,v 1.1.1.1 2003/02/15 04:56:20 zarzycki Exp $"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES #include #include #include #endif #include "db_int.h" #include "dbinc/txn.h" static int __db_xa_close __P((char *, int, long)); static int __db_xa_commit __P((XID *, int, long)); static int __db_xa_complete __P((int *, int *, int, long)); static int __db_xa_end __P((XID *, int, long)); static int __db_xa_forget __P((XID *, int, long)); static int __db_xa_open __P((char *, int, long)); static int __db_xa_prepare __P((XID *, int, long)); static int __db_xa_recover __P((XID *, long, int, long)); static int __db_xa_rollback __P((XID *, int, long)); static int __db_xa_start __P((XID *, int, long)); static void __xa_txn_end __P((DB_TXN *)); /* * Possible flag values: * Dynamic registration 0 => no dynamic registration * TMREGISTER => dynamic registration * Asynchronous operation 0 => no support for asynchrony * TMUSEASYNC => async support * Migration support 0 => migration of transactions across * threads is possible * TMNOMIGRATE => no migration across threads */ const struct xa_switch_t db_xa_switch = { "Berkeley DB", /* name[RMNAMESZ] */ TMNOMIGRATE, /* flags */ 0, /* version */ __db_xa_open, /* xa_open_entry */ __db_xa_close, /* xa_close_entry */ __db_xa_start, /* xa_start_entry */ __db_xa_end, /* xa_end_entry */ __db_xa_rollback, /* xa_rollback_entry */ __db_xa_prepare, /* xa_prepare_entry */ __db_xa_commit, /* xa_commit_entry */ __db_xa_recover, /* xa_recover_entry */ __db_xa_forget, /* xa_forget_entry */ __db_xa_complete /* xa_complete_entry */ }; /* * __db_xa_open -- * The open call in the XA protocol. The rmid field is an id number * that the TM assigned us and will pass us on every xa call. We need to * map that rmid number into a dbenv structure that we create during * initialization. Since this id number is thread specific, we do not * need to store it in shared memory. The file xa_map.c implements all * such xa->db mappings. * The xa_info field is instance specific information. We require * that the value of DB_HOME be passed in xa_info. Since xa_info is the * only thing that we get to pass to db_env_create, any config information * will have to be done via a config file instead of via the db_env_create * call. */ static int __db_xa_open(xa_info, rmid, flags) char *xa_info; int rmid; long flags; { DB_ENV *env; if (LF_ISSET(TMASYNC)) return (XAER_ASYNC); if (flags != TMNOFLAGS) return (XAER_INVAL); /* Verify if we already have this environment open. */ if (__db_rmid_to_env(rmid, &env) == 0) return (XA_OK); if (__os_calloc(env, 1, sizeof(DB_ENV), &env) != 0) return (XAER_RMERR); /* Open a new environment. */ #define XA_FLAGS \ DB_CREATE | DB_INIT_LOCK | DB_INIT_LOG | DB_INIT_MPOOL | DB_INIT_TXN if (db_env_create(&env, 0) != 0) return (XAER_RMERR); if (env->open(env, xa_info, XA_FLAGS, 0) != 0) goto err; /* Create the mapping. */ if (__db_map_rmid(rmid, env) != 0) goto err; /* Allocate space for the current transaction. */ if (__os_calloc(env, 1, sizeof(DB_TXN), &env->xa_txn) != 0) goto err; env->xa_txn->txnid = TXN_INVALID; return (XA_OK); err: (void)env->close(env, 0); return (XAER_RMERR); } /* * __db_xa_close -- * The close call of the XA protocol. The only trickiness here * is that if there are any active transactions, we must fail. It is * *not* an error to call close on an environment that has already been * closed (I am interpreting that to mean it's OK to call close on an * environment that has never been opened). */ static int __db_xa_close(xa_info, rmid, flags) char *xa_info; int rmid; long flags; { DB_ENV *env; int ret, t_ret; COMPQUIET(xa_info, NULL); if (LF_ISSET(TMASYNC)) return (XAER_ASYNC); if (flags != TMNOFLAGS) return (XAER_INVAL); /* If the environment is closed, then we're done. */ if (__db_rmid_to_env(rmid, &env) != 0) return (XA_OK); /* Check if there are any pending transactions. */ if (env->xa_txn != NULL && env->xa_txn->txnid != TXN_INVALID) return (XAER_PROTO); /* Destroy the mapping. */ ret = __db_unmap_rmid(rmid); /* Discard space held for the current transaction. */ if (env->xa_txn != NULL) __os_free(env, env->xa_txn); /* Close the environment. */ if ((t_ret = env->close(env, 0)) != 0 && ret == 0) ret = t_ret; return (ret == 0 ? XA_OK : XAER_RMERR); } /* * __db_xa_start -- * Begin a transaction for the current resource manager. */ static int __db_xa_start(xid, rmid, flags) XID *xid; int rmid; long flags; { DB_ENV *env; TXN_DETAIL *td; size_t off; int is_known; #define OK_FLAGS (TMJOIN | TMRESUME | TMNOWAIT | TMASYNC | TMNOFLAGS) if (LF_ISSET(~OK_FLAGS)) return (XAER_INVAL); if (LF_ISSET(TMJOIN) && LF_ISSET(TMRESUME)) return (XAER_INVAL); if (LF_ISSET(TMASYNC)) return (XAER_ASYNC); if (__db_rmid_to_env(rmid, &env) != 0) return (XAER_PROTO); is_known = __db_xid_to_txn(env, xid, &off) == 0; if (is_known && !LF_ISSET(TMRESUME) && !LF_ISSET(TMJOIN)) return (XAER_DUPID); if (!is_known && LF_ISSET(TMRESUME | TMJOIN)) return (XAER_NOTA); /* * This can't block, so we can ignore TMNOWAIT. * * Other error conditions: RMERR, RMFAIL, OUTSIDE, PROTO, RB* */ if (is_known) { td = (TXN_DETAIL *) R_ADDR(&((DB_TXNMGR *)env->tx_handle)->reginfo, off); if (td->xa_status == TXN_XA_SUSPENDED && !LF_ISSET(TMRESUME | TMJOIN)) return (XAER_PROTO); if (td->xa_status == TXN_XA_DEADLOCKED) return (XA_RBDEADLOCK); if (td->xa_status == TXN_XA_ABORTED) return (XA_RBOTHER); /* Now, fill in the global transaction structure. */ __txn_continue(env, env->xa_txn, td, off); td->xa_status = TXN_XA_STARTED; } else { if (__txn_xa_begin(env, env->xa_txn) != 0) return (XAER_RMERR); (void)__db_map_xid(env, xid, env->xa_txn->off); td = (TXN_DETAIL *) R_ADDR(&((DB_TXNMGR *)env->tx_handle)->reginfo, env->xa_txn->off); td->xa_status = TXN_XA_STARTED; } return (XA_OK); } /* * __db_xa_end -- * Disassociate the current transaction from the current process. */ static int __db_xa_end(xid, rmid, flags) XID *xid; int rmid; long flags; { DB_ENV *env; DB_TXN *txn; TXN_DETAIL *td; size_t off; if (flags != TMNOFLAGS && !LF_ISSET(TMSUSPEND | TMSUCCESS | TMFAIL)) return (XAER_INVAL); if (__db_rmid_to_env(rmid, &env) != 0) return (XAER_PROTO); if (__db_xid_to_txn(env, xid, &off) != 0) return (XAER_NOTA); txn = env->xa_txn; if (off != txn->off) return (XAER_PROTO); td = (TXN_DETAIL *)R_ADDR(&((DB_TXNMGR *)env->tx_handle)->reginfo, off); if (td->xa_status == TXN_XA_DEADLOCKED) return (XA_RBDEADLOCK); if (td->status == TXN_ABORTED) return (XA_RBOTHER); if (td->xa_status != TXN_XA_STARTED) return (XAER_PROTO); /* Update the shared memory last_lsn field */ td->last_lsn = txn->last_lsn; /* * If we ever support XA migration, we cannot keep SUSPEND/END * status in the shared region; it would have to be process local. */ if (LF_ISSET(TMSUSPEND)) td->xa_status = TXN_XA_SUSPENDED; else td->xa_status = TXN_XA_ENDED; txn->txnid = TXN_INVALID; return (XA_OK); } /* * __db_xa_prepare -- * Sync the log to disk so we can guarantee recoverability. */ static int __db_xa_prepare(xid, rmid, flags) XID *xid; int rmid; long flags; { DB_ENV *env; TXN_DETAIL *td; size_t off; if (LF_ISSET(TMASYNC)) return (XAER_ASYNC); if (flags != TMNOFLAGS) return (XAER_INVAL); /* * We need to know if we've ever called prepare on this. * As part of the prepare, we set the xa_status field to * reflect that fact that prepare has been called, and if * it's ever called again, it's an error. */ if (__db_rmid_to_env(rmid, &env) != 0) return (XAER_PROTO); if (__db_xid_to_txn(env, xid, &off) != 0) return (XAER_NOTA); td = (TXN_DETAIL *)R_ADDR(&((DB_TXNMGR *)env->tx_handle)->reginfo, off); if (td->xa_status == TXN_XA_DEADLOCKED) return (XA_RBDEADLOCK); if (td->xa_status != TXN_XA_ENDED && td->xa_status != TXN_XA_SUSPENDED) return (XAER_PROTO); /* Now, fill in the global transaction structure. */ __txn_continue(env, env->xa_txn, td, off); if (env->xa_txn->prepare(env->xa_txn, (u_int8_t *)xid->data) != 0) return (XAER_RMERR); td->xa_status = TXN_XA_PREPARED; /* No fatal value that would require an XAER_RMFAIL. */ __xa_txn_end(env->xa_txn); return (XA_OK); } /* * __db_xa_commit -- * Commit the transaction */ static int __db_xa_commit(xid, rmid, flags) XID *xid; int rmid; long flags; { DB_ENV *env; TXN_DETAIL *td; size_t off; if (LF_ISSET(TMASYNC)) return (XAER_ASYNC); #undef OK_FLAGS #define OK_FLAGS (TMNOFLAGS | TMNOWAIT | TMONEPHASE) if (LF_ISSET(~OK_FLAGS)) return (XAER_INVAL); /* * We need to know if we've ever called prepare on this. * We can verify this by examining the xa_status field. */ if (__db_rmid_to_env(rmid, &env) != 0) return (XAER_PROTO); if (__db_xid_to_txn(env, xid, &off) != 0) return (XAER_NOTA); td = (TXN_DETAIL *)R_ADDR(&((DB_TXNMGR *)env->tx_handle)->reginfo, off); if (td->xa_status == TXN_XA_DEADLOCKED) return (XA_RBDEADLOCK); if (td->xa_status == TXN_XA_ABORTED) return (XA_RBOTHER); if (LF_ISSET(TMONEPHASE) && td->xa_status != TXN_XA_ENDED && td->xa_status != TXN_XA_SUSPENDED) return (XAER_PROTO); if (!LF_ISSET(TMONEPHASE) && td->xa_status != TXN_XA_PREPARED) return (XAER_PROTO); /* Now, fill in the global transaction structure. */ __txn_continue(env, env->xa_txn, td, off); if (env->xa_txn->commit(env->xa_txn, 0) != 0) return (XAER_RMERR); /* No fatal value that would require an XAER_RMFAIL. */ __xa_txn_end(env->xa_txn); return (XA_OK); } /* * __db_xa_recover -- * Returns a list of prepared and heuristically completed transactions. * * The return value is the number of xids placed into the xid array (less * than or equal to the count parameter). The flags are going to indicate * whether we are starting a scan or continuing one. */ static int __db_xa_recover(xids, count, rmid, flags) XID *xids; long count, flags; int rmid; { DB_ENV *env; u_int32_t newflags; long rval; /* If the environment is closed, then we're done. */ if (__db_rmid_to_env(rmid, &env) != 0) return (XAER_PROTO); if (LF_ISSET(TMSTARTRSCAN)) newflags = DB_FIRST; else if (LF_ISSET(TMENDRSCAN)) newflags = DB_LAST; else newflags = DB_NEXT; rval = 0; if (__txn_get_prepared(env, xids, NULL, count, &rval, newflags) != 0) return (XAER_RMERR); else return (rval); } /* * __db_xa_rollback * Abort an XA transaction. */ static int __db_xa_rollback(xid, rmid, flags) XID *xid; int rmid; long flags; { DB_ENV *env; TXN_DETAIL *td; size_t off; if (LF_ISSET(TMASYNC)) return (XAER_ASYNC); if (flags != TMNOFLAGS) return (XAER_INVAL); if (__db_rmid_to_env(rmid, &env) != 0) return (XAER_PROTO); if (__db_xid_to_txn(env, xid, &off) != 0) return (XAER_NOTA); td = (TXN_DETAIL *)R_ADDR(&((DB_TXNMGR *)env->tx_handle)->reginfo, off); if (td->xa_status == TXN_XA_DEADLOCKED) return (XA_RBDEADLOCK); if (td->xa_status == TXN_XA_ABORTED) return (XA_RBOTHER); if (td->xa_status != TXN_XA_ENDED && td->xa_status != TXN_XA_SUSPENDED && td->xa_status != TXN_XA_PREPARED) return (XAER_PROTO); /* Now, fill in the global transaction structure. */ __txn_continue(env, env->xa_txn, td, off); if (env->xa_txn->abort(env->xa_txn) != 0) return (XAER_RMERR); /* No fatal value that would require an XAER_RMFAIL. */ __xa_txn_end(env->xa_txn); return (XA_OK); } /* * __db_xa_forget -- * Forget about an XID for a transaction that was heuristically * completed. Since we do not heuristically complete anything, I * don't think we have to do anything here, but we should make sure * that we reclaim the slots in the txnid table. */ static int __db_xa_forget(xid, rmid, flags) XID *xid; int rmid; long flags; { DB_ENV *env; size_t off; if (LF_ISSET(TMASYNC)) return (XAER_ASYNC); if (flags != TMNOFLAGS) return (XAER_INVAL); if (__db_rmid_to_env(rmid, &env) != 0) return (XAER_PROTO); /* * If mapping is gone, then we're done. */ if (__db_xid_to_txn(env, xid, &off) != 0) return (XA_OK); __db_unmap_xid(env, xid, off); /* No fatal value that would require an XAER_RMFAIL. */ return (XA_OK); } /* * __db_xa_complete -- * Used to wait for asynchronous operations to complete. Since we're * not doing asynch, this is an invalid operation. */ static int __db_xa_complete(handle, retval, rmid, flags) int *handle, *retval, rmid; long flags; { COMPQUIET(handle, NULL); COMPQUIET(retval, NULL); COMPQUIET(rmid, 0); COMPQUIET(flags, 0); return (XAER_INVAL); } /* * __xa_txn_end -- * Invalidate a transaction structure that was generated by __txn_continue. */ static void __xa_txn_end(txn) DB_TXN *txn; { if (txn != NULL) txn->txnid = TXN_INVALID; }