/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1998, 1999
 *	Sleepycat Software.  All rights reserved.
 */

#include "db_config.h"

#ifndef lint
static const char sccsid[] = "@(#)os_handle.c	11.2 (Sleepycat) 11/12/99";
#endif /* not lint */

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

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

#include "db_int.h"
#include "os_jump.h"

/*
 * CDB___os_openhandle --
 *	Open a file, using POSIX 1003.1 open flags.
 *
 * PUBLIC: int CDB___os_openhandle __P((const char *, int, int, DB_FH *));
 */
int
CDB___os_openhandle(name, flags, mode, fhp)
	const char *name;
	int flags, mode;
	DB_FH *fhp;
{
	int ret, try;

	memset(fhp, 0, sizeof(*fhp));

	for (ret = 0, try = 1; try < 4; ++try) {
		/*
		 * !!!
		 * Open with full sharing on VMS.
		 *
		 * We use these flags because they are the ones set by the VMS
		 * CRTL mmap() call when it opens a file, and we have to be
		 * able to open files that mmap() has previously opened, e.g.,
		 * when we're joining already existing DB regions.
		 */
		fhp->fd = CDB___db_jump.j_open != NULL ?
		    CDB___db_jump.j_open(name, flags, mode) :
#ifdef __VMS
		    open(name, flags, mode, "shr=get,put,upd,del,upi");
#else
		    open(name, flags, mode);
#endif

		if (fhp->fd == -1) {
			/*
			 * If it's a "temporary" error, we retry up to 3 times,
			 * waiting up to 12 seconds.  While it's not a problem
			 * if we can't open a database, an inability to open a
			 * log file is cause for serious dismay.
			 */
			ret = CDB___os_get_errno();
			if (ret == ENFILE || ret == EMFILE || ret == ENOSPC) {
				(void)CDB___os_sleep(try * 2, 0);
				continue;
			}
		} else
			F_SET(fhp, DB_FH_VALID);
		break;
	}
	return (ret);
}

/*
 * CDB___os_closehandle --
 *	Close a file.
 *
 * PUBLIC: int CDB___os_closehandle __P((DB_FH *));
 */
int
CDB___os_closehandle(fhp)
	DB_FH *fhp;
{
	int ret;

	/* Don't close file descriptors that were never opened. */
	DB_ASSERT(F_ISSET(fhp, DB_FH_VALID) && fhp->fd != -1);

	ret = CDB___db_jump.j_close != NULL ?
	    CDB___db_jump.j_close(fhp->fd) : close(fhp->fd);

	/*
	 * Smash the POSIX file descriptor -- it's never tested, but we want
	 * to catch any mistakes.
	 */
	fhp->fd = -1;
	F_CLR(fhp, DB_FH_VALID);

	return (ret == 0 ? 0 : CDB___os_get_errno());
}