/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1999
 *	Sleepycat Software.  All rights reserved.
 */

#include "db_config.h"

#ifndef lint
static const char sccsid[] = "@(#)db_method.c	11.8 (Sleepycat) 9/22/99";
#endif /* not lint */

#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>

#include <errno.h>
#include <string.h>
#endif

#include "db_int.h"
#include "db_page.h"
#include "db_am.h"
#include "btree.h"
#include "hash.h"
#include "qam.h"
#include "xa.h"
#include "xa_ext.h"

static int  CDB___db_get_byteswapped __P((DB *));
static DBTYPE
	    CDB___db_get_type __P((DB *));
static int  CDB___db_init __P((DB *, u_int32_t));
static int  CDB___db_set_cachesize __P((DB *, u_int32_t, u_int32_t, int));
static int  CDB___db_set_dup_compare __P((DB *, int (*)(const DBT *, const DBT *)));
static void CDB___db_set_errcall __P((DB *, void (*)(const char *, char *)));
static void CDB___db_set_errfile __P((DB *, FILE *));
static void CDB___db_set_feedback __P((DB *, void (*)(DB *, int, int)));
static int  CDB___db_set_flags __P((DB *, u_int32_t));
static int  CDB___db_set_lorder __P((DB *, int));
static int  CDB___db_set_malloc __P((DB *, void *(*)(size_t)));
static int  CDB___db_set_pagesize __P((DB *, u_int32_t));
static int  CDB___db_set_realloc __P((DB *, void *(*)(void *, size_t)));
static void CDB___db_set_errpfx __P((DB *, const char *));
static void CDB___db_set_paniccall __P((DB *, void (*)(DB_ENV *, int)));
static void CDB___dbh_err __P((DB *, int, const char *, ...));
static void CDB___dbh_errx __P((DB *, const char *, ...));

/*
 * CDB_db_create --
 *	DB constructor.
 */
int
CDB_db_create(dbpp, dbenv, flags)
	DB **dbpp;
	DB_ENV *dbenv;
	u_int32_t flags;
{
	DB *dbp;
	int ret;

	/* Check for invalid function flags. */
	switch (flags) {
	case 0:
		break;
	case DB_XA_CREATE:
		if (dbenv != NULL) {
			CDB___db_err(dbenv,
		"XA applications may not specify an environment to CDB_db_create");
			return (EINVAL);
		}

		/*
		 * If it's an XA database, open it within the XA environment,
		 * taken from the global list of environments.  (When the XA
		 * transaction manager called our xa_start() routine the
		 * "current" environment was moved to the start of the list.
		 */
		dbenv = TAILQ_FIRST(&DB_GLOBAL(db_envq));
		break;
	default:
		return (CDB___db_ferr(dbenv, "CDB_db_create", 0));
	}

	/* Allocate the DB. */
	if ((ret = CDB___os_calloc(1, sizeof(*dbp), &dbp)) != 0)
		return (ret);
	if ((ret = CDB___db_init(dbp, flags)) != 0) {
		CDB___os_free(dbp, sizeof(*dbp));
		return (ret);
	}

	/* If we don't have an environment yet, allocate a local one. */
	if (dbenv == NULL) {
		if ((ret = CDB_db_env_create(&dbenv, 0)) != 0) {
			CDB___os_free(dbp, sizeof(*dbp));
			return (ret);
		}
		F_SET(dbenv, DB_ENV_DBLOCAL);
	}

	dbp->dbenv = dbenv;

	*dbpp = dbp;
	return (0);
}

/*
 * CDB___db_init --
 *	Initialize a DB structure.
 */
static int
CDB___db_init(dbp, flags)
	DB *dbp;
	u_int32_t flags;
{
	int ret;

	dbp->pgsize = DB_DEF_IOSIZE;

	dbp->log_fileid = DB_LOGFILEID_INVALID;

	TAILQ_INIT(&dbp->free_queue);
	TAILQ_INIT(&dbp->active_queue);

	FLD_SET(dbp->am_ok,
	    DB_OK_BTREE | DB_OK_HASH | DB_OK_QUEUE | DB_OK_RECNO);

	dbp->close = CDB___db_close;
	dbp->cursor = CDB___db_cursor;
	dbp->del = NULL;		/* !!! Must be set by access method. */
	dbp->err = CDB___dbh_err;
	dbp->errx = CDB___dbh_errx;
	dbp->fd = CDB___db_fd;
	dbp->get = CDB___db_get;
	dbp->get_byteswapped = CDB___db_get_byteswapped;
	dbp->get_type = CDB___db_get_type;
	dbp->join = CDB___db_join;
	dbp->open = CDB___db_open;
	dbp->put = CDB___db_put;
	dbp->remove = CDB___db_remove;
	dbp->set_cachesize = CDB___db_set_cachesize;
	dbp->set_dup_compare = CDB___db_set_dup_compare;
	dbp->set_errcall = CDB___db_set_errcall;
	dbp->set_errfile = CDB___db_set_errfile;
	dbp->set_errpfx = CDB___db_set_errpfx;
	dbp->set_feedback = CDB___db_set_feedback;
	dbp->set_flags = CDB___db_set_flags;
	dbp->set_lorder = CDB___db_set_lorder;
	dbp->set_malloc = CDB___db_set_malloc;
	dbp->set_pagesize = CDB___db_set_pagesize;
	dbp->set_paniccall = CDB___db_set_paniccall;
	dbp->set_realloc = CDB___db_set_realloc;
	dbp->stat = NULL;		/* !!! Must be set by access method. */
	dbp->sync = CDB___db_sync;
	dbp->upgrade = CDB___db_upgrade;
					/* Access method specific. */
	if ((ret = CDB___bam_db_create(dbp)) != 0)
		return (ret);
	if ((ret = CDB___ham_db_create(dbp)) != 0)
		return (ret);
	if ((ret = CDB___qam_db_create(dbp)) != 0)
		return (ret);

	/*
	 * XA specific: must be last, as we replace methods set by the
	 * access methods.
	 */
	if (LF_ISSET(DB_XA_CREATE) && (ret = CDB___db_xa_create(dbp)) != 0)
		return (ret);

	F_SET(dbp, DB_AM_PGDEF);

	return (0);
}

/*
 * CDB___dbh_am_chk --
 *	Error if an unreasonable method is called.
 *
 * PUBLIC: int CDB___dbh_am_chk __P((DB *, u_int32_t));
 */
int
CDB___dbh_am_chk(dbp, flags)
	DB *dbp;
	u_int32_t flags;
{
	/*
	 * We start out allowing any access methods to be called, and as the
	 * application calls the methods the options become restricted.  The
	 * idea is to quit as soon as an illegal method combination is called.
	 */
	if ((LF_ISSET(DB_OK_BTREE) && FLD_ISSET(dbp->am_ok, DB_OK_BTREE)) ||
	    (LF_ISSET(DB_OK_HASH) && FLD_ISSET(dbp->am_ok, DB_OK_HASH)) ||
	    (LF_ISSET(DB_OK_QUEUE) && FLD_ISSET(dbp->am_ok, DB_OK_QUEUE)) ||
	    (LF_ISSET(DB_OK_RECNO) && FLD_ISSET(dbp->am_ok, DB_OK_RECNO))) {
		FLD_CLR(dbp->am_ok, ~flags);
		return (0);
	}

	CDB___db_err(dbp->dbenv,
    "call implies an access method which is inconsistent with previous calls");
	return (EINVAL);
}

/*
 * CDB___dbh_err --
 *	Error message, including the standard error string.
 */
static void
#ifdef __STDC__
CDB___dbh_err(DB *dbp, int error, const char *fmt, ...)
#else
CDB___dbh_err(dbp, error, fmt, va_alist)
	DB *dbp;
	int error;
	const char *fmt;
	va_dcl
#endif
{
	va_list ap;

#ifdef __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif
	CDB___db_real_err(dbp->dbenv, error, 1, 1, fmt, ap);

	va_end(ap);
}

/*
 * CDB___dbh_errx --
 *	Error message.
 */
static void
#ifdef __STDC__
CDB___dbh_errx(DB *dbp, const char *fmt, ...)
#else
CDB___dbh_errx(dbp, fmt, va_alist)
	DB *dbp;
	const char *fmt;
	va_dcl
#endif
{
	va_list ap;

#ifdef __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif
	CDB___db_real_err(dbp->dbenv, 0, 0, 1, fmt, ap);

	va_end(ap);
}

/*
 * CDB___db_get_byteswapped --
 *	Return if database requires byte swapping.
 */
static int
CDB___db_get_byteswapped(dbp)
	DB *dbp;
{
	DB_ILLEGAL_BEFORE_OPEN(dbp, "get_byteswapped");

	return (F_ISSET(dbp, DB_AM_SWAP) ? 1 : 0);
}

/*
 * CDB___db_get_type --
 *	Return type of underlying database.
 */
static DBTYPE
CDB___db_get_type(dbp)
	DB *dbp;
{
	DB_ILLEGAL_BEFORE_OPEN(dbp, "get_type");

	return (dbp->type);
}

/*
 * CDB___db_set_cachesize --
 *	Set underlying cache size.
 */
static int
CDB___db_set_cachesize(dbp, cache_gbytes, cache_bytes, ncache)
	DB *dbp;
	u_int32_t cache_gbytes, cache_bytes;
	int ncache;
{
	DB_ILLEGAL_IN_ENV(dbp, "set_cachesize");
	DB_ILLEGAL_AFTER_OPEN(dbp, "set_cachesize");

	return (dbp->dbenv->set_cachesize(
	    dbp->dbenv, cache_gbytes, cache_bytes, ncache));
}

/*
 * CDB___db_set_dup_compare --
 *	Set duplicate comparison routine.
 */
static int
CDB___db_set_dup_compare(dbp, func)
	DB *dbp;
	int (*func) __P((const DBT *, const DBT *));
{
	DB_ILLEGAL_AFTER_OPEN(dbp, "dup_compare");
	DB_ILLEGAL_METHOD(dbp, DB_OK_BTREE | DB_OK_HASH);

	dbp->dup_compare = func;

	return (0);
}

static void
CDB___db_set_errcall(dbp, errcall)
	DB *dbp;
	void (*errcall) __P((const char *, char *));
{
	dbp->dbenv->set_errcall(dbp->dbenv, errcall);
}

static void
CDB___db_set_errfile(dbp, errfile)
	DB *dbp;
	FILE *errfile;
{
	dbp->dbenv->set_errfile(dbp->dbenv, errfile);
}

static void
CDB___db_set_errpfx(dbp, errpfx)
	DB *dbp;
	const char *errpfx;
{
	dbp->dbenv->set_errpfx(dbp->dbenv, errpfx);
}

static void
CDB___db_set_feedback(dbp, feedback)
	DB *dbp;
	void (*feedback) __P((DB *, int, int));
{
	dbp->db_feedback = feedback;
}

static int
CDB___db_set_flags(dbp, flags)
	DB *dbp;
	u_int32_t flags;
{
	int ret;

	/*
	 * !!!
	 * The hash access method only takes two flags: DB_DUP and DB_DUPSORT.
	 * The Btree access method uses them for the same purposes, and so we
	 * resolve them there.
	 *
	 * The queue access method takes no flags.
	 */
	if ((ret = CDB___bam_set_flags(dbp, &flags)) != 0)
		return (ret);
	if ((ret = CDB___ram_set_flags(dbp, &flags)) != 0)
		return (ret);

	return (flags == 0 ? 0 : CDB___db_ferr(dbp->dbenv, "DB->set_flags", 0));
}

static int
CDB___db_set_lorder(dbp, db_lorder)
	DB *dbp;
	int db_lorder;
{
	int ret;

	DB_ILLEGAL_AFTER_OPEN(dbp, "set_lorder");

	/* Flag if the specified byte order requires swapping. */
	switch (ret = CDB___db_byteorder(dbp->dbenv, db_lorder)) {
	case 0:
		F_CLR(dbp, DB_AM_SWAP);
		break;
	case DB_SWAPBYTES:
		F_SET(dbp, DB_AM_SWAP);
		break;
	default:
		return (ret);
		/* NOTREACHED */
	}
	return (0);
}

static int
CDB___db_set_malloc(dbp, func)
	DB *dbp;
	void *(*func) __P((size_t));
{
	DB_ILLEGAL_AFTER_OPEN(dbp, "set_malloc");

	dbp->db_malloc = func;
	return (0);
}

static int
CDB___db_set_pagesize(dbp, db_pagesize)
	DB *dbp;
	u_int32_t db_pagesize;
{
	DB_ILLEGAL_AFTER_OPEN(dbp, "set_pagesize");

	if (db_pagesize < DB_MIN_PGSIZE) {
		CDB___db_err(dbp->dbenv, "page sizes may not be smaller than %lu",
		    (u_long)DB_MIN_PGSIZE);
		return (EINVAL);
	}
	if (db_pagesize > DB_MAX_PGSIZE) {
		CDB___db_err(dbp->dbenv, "page sizes may not be larger than %lu",
		    (u_long)DB_MAX_PGSIZE);
		return (EINVAL);
	}

	/*
	 * We don't want anything that's not a power-of-2, as we rely on that
	 * for alignment of various types on the pages.
	 */
	if ((u_int32_t)1 << CDB___db_log2(db_pagesize) != db_pagesize) {
		CDB___db_err(dbp->dbenv, "page sizes must be a power-of-2");
		return (EINVAL);
	}

	/*
	 * XXX
	 * Should we be checking for a page size that's not a multiple of 512,
	 * so that we never try and write less than a disk sector?
	 */

	F_CLR(dbp, DB_AM_PGDEF);
	dbp->pgsize = db_pagesize;

	return (0);
}

static int
CDB___db_set_realloc(dbp, func)
	DB *dbp;
	void *(*func) __P((void *, size_t));
{
	DB_ILLEGAL_AFTER_OPEN(dbp, "set_realloc");

	dbp->db_realloc = func;
	return (0);
}

static void
CDB___db_set_paniccall(dbp, paniccall)
	DB *dbp;
	void (*paniccall) __P((DB_ENV *, int));
{
	dbp->dbenv->set_paniccall(dbp->dbenv, paniccall);
}