1 files changed, 430 insertions, 0 deletions
diff --git a/db2/db/db_am.c b/db2/db/db_am.c
new file mode 100644
index 0000000000..e02ad57f53
--- /dev/null
+++ b/db2/db/db_am.c
@@ -0,0 +1,430 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1998
+ *	Sleepycat Software.  All rights reserved.
+ */
+
+#include "config.h"
+
+#ifndef lint
+static const char sccsid[] = "@(#)db_am.c	10.15 (Sleepycat) 12/30/98";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#endif
+
+#include "db_int.h"
+#include "shqueue.h"
+#include "db_page.h"
+#include "db_shash.h"
+#include "mp.h"
+#include "btree.h"
+#include "hash.h"
+#include "db_am.h"
+#include "db_ext.h"
+
+static int __db_c_close __P((DBC *));
+static int __db_cursor __P((DB *, DB_TXN *, DBC **, u_int32_t));
+static int __db_fd __P((DB *, int *));
+static int __db_get __P((DB *, DB_TXN *, DBT *, DBT *, u_int32_t));
+static int __db_put __P((DB *, DB_TXN *, DBT *, DBT *, u_int32_t));
+
+/*
+ * __db_init_wrapper --
+ *	Wrapper layer to implement generic DB functions.
+ *
+ * PUBLIC: int __db_init_wrapper __P((DB *));
+ */
+int
+__db_init_wrapper(dbp)
+	DB *dbp;
+{
+	dbp->close = __db_close;
+	dbp->cursor = __db_cursor;
+	dbp->del = NULL;		/* !!! Must be set by access method. */
+	dbp->fd = __db_fd;
+	dbp->get = __db_get;
+	dbp->join = __db_join;
+	dbp->put = __db_put;
+	dbp->stat = NULL;		/* !!! Must be set by access method. */
+	dbp->sync = __db_sync;
+
+	return (0);
+}
+
+/*
+ * __db_cursor --
+ *	Allocate and return a cursor.
+ */
+static int
+__db_cursor(dbp, txn, dbcp, flags)
+	DB *dbp;
+	DB_TXN *txn;
+	DBC **dbcp;
+	u_int32_t flags;
+{
+	DBC *dbc, *adbc;
+	int ret;
+	db_lockmode_t mode;
+	u_int32_t op;
+
+	DB_PANIC_CHECK(dbp);
+
+	/* Take one from the free list if it's available. */
+	DB_THREAD_LOCK(dbp);
+	if ((dbc = TAILQ_FIRST(&dbp->free_queue)) != NULL)
+		TAILQ_REMOVE(&dbp->free_queue, dbc, links);
+	else {
+		DB_THREAD_UNLOCK(dbp);
+
+		if ((ret = __os_calloc(1, sizeof(DBC), &dbc)) != 0)
+			return (ret);
+
+		dbc->dbp = dbp;
+		dbc->c_close = __db_c_close;
+
+		/* Set up locking information. */
+		if (F_ISSET(dbp, DB_AM_LOCKING | DB_AM_CDB)) {
+ 			/*
+ 			 * If we are not threaded, then there is no need to
+ 			 * create new locker ids.  We know that no one else
+ 			 * is running concurrently using this DB, so we can
+ 			 * take a peek at any cursors on the active queue.
+ 			 */
+ 			if (!F_ISSET(dbp, DB_AM_THREAD) &&
+ 			    (adbc = TAILQ_FIRST(&dbp->active_queue)) != NULL)
+ 				dbc->lid = adbc->lid;
+ 			else
+ 				if ((ret = lock_id(dbp->dbenv->lk_info,
+ 				    &dbc->lid)) != 0)
+ 					goto err;
+ 
+			memcpy(dbc->lock.fileid, dbp->fileid, DB_FILE_ID_LEN);
+			if (F_ISSET(dbp, DB_AM_CDB)) {
+				dbc->lock_dbt.size = DB_FILE_ID_LEN;
+				dbc->lock_dbt.data = dbc->lock.fileid;
+			} else {
+				dbc->lock_dbt.size = sizeof(dbc->lock);
+				dbc->lock_dbt.data = &dbc->lock;
+			}
+		}
+
+		switch (dbp->type) {
+		case DB_BTREE:
+		case DB_RECNO:
+			if ((ret = __bam_c_init(dbc)) != 0)
+				goto err;
+			break;
+		case DB_HASH:
+			if ((ret = __ham_c_init(dbc)) != 0)
+				goto err;
+			break;
+		default:
+			ret = EINVAL;
+			goto err;
+		}
+
+		DB_THREAD_LOCK(dbp);
+	}
+
+	if ((dbc->txn = txn) == NULL)
+		dbc->locker = dbc->lid;
+	else
+		dbc->locker = txn->txnid;
+
+	TAILQ_INSERT_TAIL(&dbp->active_queue, dbc, links);
+	DB_THREAD_UNLOCK(dbp);
+
+	/*
+	 * If this is the concurrent DB product, then we do all locking
+	 * in the interface, which is right here.
+	 */
+	if (F_ISSET(dbp, DB_AM_CDB)) {
+		op = LF_ISSET(DB_OPFLAGS_MASK);
+		mode = (op == DB_WRITELOCK) ? DB_LOCK_WRITE :
+		    (LF_ISSET(DB_RMW) ? DB_LOCK_IWRITE : DB_LOCK_READ);
+		if ((ret = lock_get(dbp->dbenv->lk_info, dbc->locker, 0,
+		    &dbc->lock_dbt, mode, &dbc->mylock)) != 0) {
+			(void)__db_c_close(dbc);
+			return (EAGAIN);
+		}
+		if (LF_ISSET(DB_RMW))
+			F_SET(dbc, DBC_RMW);
+		if (op == DB_WRITELOCK)
+			F_SET(dbc, DBC_WRITER);
+	}
+
+	*dbcp = dbc;
+	return (0);
+
+err:	__os_free(dbc, sizeof(*dbc));
+	return (ret);
+}
+
+/*
+ * __db_c_close --
+ *	Close the cursor (recycle for later use).
+ */
+static int
+__db_c_close(dbc)
+	DBC *dbc;
+{
+	DB *dbp;
+	int ret, t_ret;
+
+	dbp = dbc->dbp;
+
+	DB_PANIC_CHECK(dbp);
+
+	ret = 0;
+
+	/*
+	 * We cannot release the lock until after we've called the
+	 * access method specific routine, since btrees may have pending
+	 * deletes.
+	 */
+
+	/* Remove the cursor from the active queue. */
+	DB_THREAD_LOCK(dbp);
+	TAILQ_REMOVE(&dbp->active_queue, dbc, links);
+	DB_THREAD_UNLOCK(dbp);
+
+	/* Call the access specific cursor close routine. */
+	if ((t_ret = dbc->c_am_close(dbc)) != 0 && ret == 0)
+		t_ret = ret;
+
+	/* Release the lock. */
+	if (F_ISSET(dbc->dbp, DB_AM_CDB) && dbc->mylock != LOCK_INVALID) {
+		ret = lock_put(dbc->dbp->dbenv->lk_info, dbc->mylock);
+		dbc->mylock = LOCK_INVALID;
+	}
+
+	/* Clean up the cursor. */
+	dbc->flags = 0;
+
+#ifdef DEBUG
+	/*
+	 * Check for leftover locks, unless we're running with transactions.
+	 *
+	 * If we're running tests, display any locks currently held.  It's
+	 * possible that some applications may hold locks for long periods,
+	 * e.g., conference room locks, but the DB tests should never close
+	 * holding locks.
+	 */
+	if (F_ISSET(dbp, DB_AM_LOCKING) && dbc->lid == dbc->locker) {
+		DB_LOCKREQ request;
+
+		request.op = DB_LOCK_DUMP;
+		if ((t_ret = lock_vec(dbp->dbenv->lk_info,
+		    dbc->locker, 0, &request, 1, NULL)) != 0 && ret == 0)
+			ret = EAGAIN;
+	}
+#endif
+	/* Move the cursor to the free queue. */
+	DB_THREAD_LOCK(dbp);
+	TAILQ_INSERT_TAIL(&dbp->free_queue, dbc, links);
+	DB_THREAD_UNLOCK(dbp);
+
+	return (ret);
+}
+
+#ifdef DEBUG
+/*
+ * __db_cprint --
+ *	Display the current cursor list.
+ *
+ * PUBLIC: int __db_cprint __P((DB *));
+ */
+int
+__db_cprint(dbp)
+	DB *dbp;
+{
+	static const FN fn[] = {
+		{ DBC_RECOVER, 	"recover" },
+		{ DBC_RMW, 	"read-modify-write" },
+		{ 0 },
+	};
+	DBC *dbc;
+
+	DB_THREAD_LOCK(dbp);
+	for (dbc = TAILQ_FIRST(&dbp->active_queue);
+	    dbc != NULL; dbc = TAILQ_NEXT(dbc, links)) {
+		fprintf(stderr,
+		    "%#0x: dbp: %#0x txn: %#0x lid: %lu locker: %lu",
+		    (u_int)dbc, (u_int)dbc->dbp, (u_int)dbc->txn,
+		    (u_long)dbc->lid, (u_long)dbc->locker);
+		__db_prflags(dbc->flags, fn, stderr);
+		fprintf(stderr, "\n");
+	}
+	DB_THREAD_UNLOCK(dbp);
+
+	return (0);
+}
+#endif /* DEBUG */
+
+/*
+ * __db_c_destroy --
+ *	Destroy the cursor.
+ *
+ * PUBLIC: int __db_c_destroy __P((DBC *));
+ */
+int
+__db_c_destroy(dbc)
+	DBC *dbc;
+{
+	DB *dbp;
+	int ret;
+
+	dbp = dbc->dbp;
+
+	/* Remove the cursor from the free queue. */
+	DB_THREAD_LOCK(dbp);
+	TAILQ_REMOVE(&dbp->free_queue, dbc, links);
+	DB_THREAD_UNLOCK(dbp);
+
+	/* Call the access specific cursor destroy routine. */
+	ret = dbc->c_am_destroy == NULL ? 0 : dbc->c_am_destroy(dbc);
+
+	/* Free up allocated memory. */
+	if (dbc->rkey.data != NULL)
+		__os_free(dbc->rkey.data, dbc->rkey.ulen);
+	if (dbc->rdata.data != NULL)
+		__os_free(dbc->rdata.data, dbc->rdata.ulen);
+	__os_free(dbc, sizeof(*dbc));
+
+	return (0);
+}
+
+/*
+ * db_fd --
+ *	Return a file descriptor for flock'ing.
+ */
+static int
+__db_fd(dbp, fdp)
+        DB *dbp;
+	int *fdp;
+{
+	DB_PANIC_CHECK(dbp);
+
+	/*
+	 * XXX
+	 * Truly spectacular layering violation.
+	 */
+	return (__mp_xxx_fd(dbp->mpf, fdp));
+}
+
+/*
+ * __db_get --
+ *	Return a key/data pair.
+ */
+static int
+__db_get(dbp, txn, key, data, flags)
+	DB *dbp;
+	DB_TXN *txn;
+	DBT *key, *data;
+	u_int32_t flags;
+{
+	DBC *dbc;
+	int ret, t_ret;
+
+	DB_PANIC_CHECK(dbp);
+
+	if ((ret = __db_getchk(dbp, key, data, flags)) != 0)
+		return (ret);
+
+	if ((ret = dbp->cursor(dbp, txn, &dbc, 0)) != 0)
+		return (ret);
+
+	DEBUG_LREAD(dbc, txn, "__db_get", key, NULL, flags);
+
+	ret = dbc->c_get(dbc, key, data,
+	    flags == 0 || flags == DB_RMW ? flags | DB_SET : flags);
+
+	if ((t_ret = __db_c_close(dbc)) != 0 && ret == 0)
+		ret = t_ret;
+
+	return (ret);
+}
+
+/*
+ * __db_put --
+ *	Store a key/data pair.
+ */
+static int
+__db_put(dbp, txn, key, data, flags)
+	DB *dbp;
+	DB_TXN *txn;
+	DBT *key, *data;
+	u_int32_t flags;
+{
+	DBC *dbc;
+	DBT tdata;
+	int ret, t_ret;
+
+	DB_PANIC_CHECK(dbp);
+
+	if ((ret = __db_putchk(dbp, key, data,
+	    flags, F_ISSET(dbp, DB_AM_RDONLY), F_ISSET(dbp, DB_AM_DUP))) != 0)
+		return (ret);
+
+	if ((ret = dbp->cursor(dbp, txn, &dbc, DB_WRITELOCK)) != 0)
+		return (ret);
+
+	DEBUG_LWRITE(dbc, txn, "__db_put", key, data, flags);
+
+	if (flags == DB_NOOVERWRITE) {
+		/*
+		 * Set DB_DBT_USERMEM, this might be a threaded application and
+		 * the flags checking will catch us.  We don't want the actual
+		 * data, so request a partial of length 0.
+		 */
+		memset(&tdata, 0, sizeof(tdata));
+		F_SET(&tdata, DB_DBT_USERMEM | DB_DBT_PARTIAL);
+		if ((ret = dbc->c_get(dbc, key, &tdata, DB_SET | DB_RMW)) == 0)
+			ret = DB_KEYEXIST;
+		else
+			ret = 0;
+	}
+	if (ret == 0)
+		ret = dbc->c_put(dbc, key, data, DB_KEYLAST);
+
+	if ((t_ret = __db_c_close(dbc)) != 0 && ret == 0)
+		ret = t_ret;
+
+	return (ret);
+}
+
+/*
+ * __db_sync --
+ *	Flush the database cache.
+ *
+ * PUBLIC: int __db_sync __P((DB *, u_int32_t));
+ */
+int
+__db_sync(dbp, flags)
+	DB *dbp;
+	u_int32_t flags;
+{
+	int ret;
+
+	DB_PANIC_CHECK(dbp);
+
+	if ((ret = __db_syncchk(dbp, flags)) != 0)
+		return (ret);
+
+	/* If it wasn't possible to modify the file, we're done. */
+	if (F_ISSET(dbp, DB_AM_INMEM | DB_AM_RDONLY))
+		return (0);
+
+	/* Flush any dirty pages from the cache to the backing file. */
+	if ((ret = memp_fsync(dbp->mpf)) == DB_INCOMPLETE)
+		ret = 0;
+
+	return (ret);
+}