/*
 *	PROGRAM:	JRD Journal Server
 *	MODULE:		oldr.c
 *	DESCRIPTION:
 *
 * The contents of this file are subject to the Interbase Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy
 * of the License at http://www.Inprise.com/IPL.html
 *
 * Software distributed under the License is distributed on an
 * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
 * or implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code was created by Inprise Corporation
 * and its predecessors. Portions created by Inprise Corporation are
 * Copyright (C) Inprise Corporation.
 *
 * All Rights Reserved.
 * Contributor(s): ______________________________________.
 */

#include "firebird.h"
#include "../jrd/ib_stdio.h"
#include <stdlib.h>
#include <string.h>
#ifdef VMS
#include <file.h>
#else
#include <fcntl.h>
#endif
#include "../jrd/old.h"
#include "../jrd/llio.h"
#include "../journal/miscj_proto.h"
#include "../journal/oldr_proto.h"
#include "../jrd/llio_proto.h"


static int close_cur_file(OLD);
static int open_next_file(OLD);
static SLONG oldr_open_file(OLD);


int OLDR_close( OLD * OLD_handle)
{
/**************************************
 *
 *	O L D R _ c l o s e
 *
 **************************************
 *
 * Functional description
 *	Close the OLD file after at end of scan.
 *
 **************************************/
	OLD old;

	old = *OLD_handle;

	if (old->old_fd) {
		if (LLIO_close(0, old->old_fd))
			return FB_FAILURE;
	}

	if (old) {
		MISC_free_jrnl((int *) old->old_block->ob_hdr);
		MISC_free_jrnl((int *) old->old_block);
		MISC_free_jrnl((int *) old);
	}

	*OLD_handle = NULL;

	return FB_SUCCESS;
}


int OLDR_get( OLD OLD_handle, SCHAR * logrec, SSHORT * len)
{
/**************************************
 *
 *	O L D R _ g e t
 *
 **************************************
 *
 * Functional description
 *	Get a record from the OLD file.
 *	return
 *		0	OK
 *		OLD_EOD	Done
 *		OLD_EOF	EOF
 *	        OLD_ERR	error
 *
 **************************************/
	OLD_HDR hdr;
	OLDBLK ob;
	SLONG read_len;

	ob = OLD_handle->old_block;
	hdr = ob->ob_hdr;

	if (LLIO_read(0, OLD_handle->old_fd, 0, 0L, LLIO_SEEK_NONE,
				  (UCHAR *) hdr, OLD_handle->old_rec_size, &read_len))
		return (OLD_ERR);

	if (hdr->oh_type == OLD_EOD)
		return OLD_EOD;			// all done

	if ((hdr->oh_type != OLD_DATA) ||
		(hdr->oh_seqno != OLD_handle->old_cur_seqno)) return OLD_EOF;

	read_len = hdr->oh_hdr_len;
	memcpy(logrec, hdr->oh_buf, read_len);

	OLD_handle->old_cur_seqno++;
	*len = read_len;

	return 0;
}


void OLDR_get_info(OLD OLD_handle,
				   SSHORT * db_page_size,
				   SSHORT * dump_id,
				   SLONG * log_seqno,
				   SLONG * log_offset,
				   SLONG * log_p_offset)
{
/**************************************
 *
 *	O L D R _ g e t _ i n f o
 *
 **************************************
 *
 * Functional description
 *	Get old information
 *
 **************************************/
	if (!OLD_handle)
		return;

	*db_page_size = OLD_handle->old_db_page_size;
	*dump_id = OLD_handle->old_dump_id;
	*log_seqno = OLD_handle->old_log_seqno;
	*log_offset = OLD_handle->old_log_offset;
	*log_p_offset = OLD_handle->old_log_p_offset;
}


int OLDR_open(
			  OLD * OLD_handle,
			  SCHAR * dbname, SSHORT num_files, SCHAR ** files)
{
/**************************************
 *
 *	O L D R _ o p e n
 *
 **************************************
 *
 * Functional description
 *	Open a OLD file for reading. Used during recovery
 *	If a non NULL OLD is passed in, start from where we
 *	left off.
 *
 **************************************/
	OLD old;

	if (*OLD_handle == NULL) {
		*OLD_handle = old = (OLD) MISC_alloc_jrnl(sizeof(struct old));
		old->old_block = (OLDBLK) MISC_alloc_jrnl(sizeof(struct oldblk));
		old->old_block->ob_hdr = (OLD_HDR) MISC_alloc_jrnl(MAX_OLDBUFLEN);

		old->old_num_files = num_files;
		old->old_files = files;
		old->old_file_size = 0;
		old->old_db = dbname;
	}
	else {
		old = *OLD_handle;
	}

// Open the first file

	if (open_next_file(old) == FB_FAILURE)
		return FB_FAILURE;

	return FB_SUCCESS;
}


static int close_cur_file( OLD old)
{
/**************************************
 *
 *	c l o s e _ c u r _ f i l e
 *
 **************************************
 *
 * Functional description
 *	returns FB_SUCCESS - if things work
 *		FB_FAILURE - close fails
 *
 **************************************/

	if (LLIO_close(0, old->old_fd))
		return FB_FAILURE;

	old->old_fd = 0;
	old->old_cur_size = 0;

	return FB_SUCCESS;
}


static int open_next_file( OLD old)
{
/**************************************
 *
 *	o p e n _ n e x t _ f i l e
 *
 **************************************
 *
 * Functional description
 *	Opens the next OnLine Dump file and writes out the header.
 *
 *	returns FB_SUCCESS - if things work
 *		FB_FAILURE - open fails, no more file etc.
 *
 **************************************/
	int fd;

	if (old->old_fd) {
		if (close_cur_file(old) == FB_FAILURE)
			return FB_FAILURE;
	}

	if (old->old_cur_file >= old->old_num_files)
		return FB_FAILURE;

	if ((fd = oldr_open_file(old)) == FB_FAILURE)
		return FB_FAILURE;

	old->old_cur_file++;
	old->old_file_seqno++;

	old->old_fd = fd;

	return FB_SUCCESS;
}


static SLONG oldr_open_file( OLD old)
{
/**************************************
 *
 *	o l d r _ o p e n _ f i l e
 *
 **************************************
 *
 * Functional description
 *	Open next file and read header 
 *
 *	returns FB_SUCCESS - if things work
 *		FB_FAILURE - open fails/out of sequence etc.
 *
 **************************************/
	OLD_HDR hdr;
	OLD_HDR_PAGE hp;
	OLDBLK ob;
	SLONG fd;
	SLONG len;
	SCHAR buf[MAXPATHLEN];
	struct hdr_page header;

	ob = old->old_block;
	hdr = ob->ob_hdr;

	if (LLIO_open(0, old->old_files[old->old_cur_file], LLIO_OPEN_R,
				  TRUE, &fd)) return FB_FAILURE;

	if (LLIO_read(0, fd, 0, 0L, LLIO_SEEK_NONE,
				  (UCHAR *) hdr, OLD_HEADER_SIZE, &len) ||
		len != OLD_HEADER_SIZE) return FB_FAILURE;

	hp = (OLD_HDR_PAGE) hdr->oh_buf;
	memcpy((SCHAR *) & header, (SCHAR *) hp, sizeof(struct hdr_page));

	old->old_file_size = header.hp_file_size;

	if (header.hp_file_seqno != old->old_cur_file)
		return FB_FAILURE;

	if (header.hp_version != OLD_VERSION)
		return FB_FAILURE;

	if (header.hp_start_block != old->old_cur_seqno)
		return FB_FAILURE;

	if (old->old_block->ob_hdr->oh_type != OLD_HEADER)
		return FB_FAILURE;

	old->old_rec_size = header.hp_rec_size;
	old->old_dump_id = header.hp_dump_id;
	old->old_log_seqno = header.hp_log_seqno;
	old->old_log_offset = header.hp_log_offset;
	old->old_log_p_offset = header.hp_log_p_offset;
	old->old_db_page_size = header.hp_db_page_size;

	len = strlen(old->old_db);
	if (len != header.hp_length)
		return FB_FAILURE;

// compare database name

	memcpy(buf, hp->hp_db, len);
	buf[len] = 0;
	if (strcmp(buf, old->old_db))
		return FB_FAILURE;

	old->old_cur_size = OLD_HEADER_SIZE;

	return fd;
}