mirror of
https://github.com/FirebirdSQL/firebird.git
synced 2025-01-27 06:03:02 +01:00
115 lines
4.1 KiB
C++
115 lines
4.1 KiB
C++
/*
|
|
* PROGRAM: JRD Access Method
|
|
* MODULE: blb.h
|
|
* DESCRIPTION: Blob handling definitions
|
|
*
|
|
* 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): ______________________________________.
|
|
*/
|
|
|
|
#ifndef JRD_BLB_H
|
|
#define JRD_BLB_H
|
|
|
|
/* Blob id. A blob has two states -- temporary and permanent. In each
|
|
case, the blob id is 8 bytes (2 longwords) long. In the case of a
|
|
temporary blob, the first word is NULL and the second word points to
|
|
an internal blob block. In the case of a permanent blob, the first
|
|
word contains the relation id of the blob and the second the record
|
|
number of the first segment-clump. The two types of blobs can be
|
|
reliably distinguished by a zero or non-zero relation id. */
|
|
|
|
typedef struct bid {
|
|
#ifndef DECOSF
|
|
ULONG bid_relation_id; /* Relation id (or null) */
|
|
union {
|
|
class blb *bid_blob; /* Pointer to blob block */
|
|
ULONG bid_number; /* Record number */
|
|
} bid_stuff;
|
|
#else
|
|
union {
|
|
ULONG bid_blob; /* Low end of pointer to blob block */
|
|
ULONG bid_number; /* Record number */
|
|
} bid_stuff;
|
|
USHORT bid_blob2; /* High end of pointer to blob block */
|
|
USHORT bid_relation_id; /* Relation id (or null) */
|
|
#endif
|
|
} *BID;
|
|
|
|
/* Your basic blob block. */
|
|
|
|
class blb : public pool_alloc_rpt<UCHAR, type_blb>
|
|
{
|
|
public:
|
|
att *blb_attachment; /* database attachment */
|
|
rel *blb_relation; /* Relation, if known */
|
|
struct tra *blb_transaction; /* Parent transaction block */
|
|
blb *blb_next; /* Next blob in transaction */
|
|
UCHAR *blb_segment; /* Next segment to be addressed */
|
|
struct ctl *blb_filter; /* Blob filter control block, if any */
|
|
struct bid blb_blob_id; /* Id of materialized blob */
|
|
struct req *blb_request; /* request that assigned temporary blob */
|
|
vcl *blb_pages; /* Vector of pages */
|
|
USHORT blb_pointers; /* Max pointer on a page */
|
|
USHORT blb_level; /* Storage type */
|
|
USHORT blb_max_segment; /* Longest segment */
|
|
USHORT blb_flags; /* Interesting stuff (see below) */
|
|
USHORT blb_clump_size; /* Size of data clump */
|
|
USHORT blb_space_remaining; /* Data space left */
|
|
USHORT blb_max_pages; /* Max pages in vector */
|
|
USHORT blb_fragment_size; /* Residual fragment size */
|
|
USHORT blb_source_interp; /* source interp (for writing) */
|
|
USHORT blb_target_interp; /* destination interp (for reading) */
|
|
SSHORT blb_sub_type; /* Blob's declared sub-type */
|
|
ULONG blb_sequence; /* Blob page sequence */
|
|
ULONG blb_max_sequence; /* Number of data pages */
|
|
ULONG blb_count; /* Number of segments */
|
|
ULONG blb_length; /* Total length of data sans segments */
|
|
ULONG blb_lead_page; /* First page number */
|
|
ULONG blb_seek; /* Seek location */
|
|
/* blb_data must be longword aligned */
|
|
UCHAR blb_data[1]; /* A page's worth of blob */
|
|
};
|
|
typedef blb *BLB;
|
|
|
|
#define BLB_temporary 1 /* Newly created blob */
|
|
#define BLB_eof 2 /* This blob is exhausted */
|
|
#define BLB_stream 4 /* Stream style blob */
|
|
#define BLB_closed 8 /* Temporary blob has been closed */
|
|
#define BLB_damaged 16 /* Blob is busted */
|
|
#define BLB_seek 32 /* Seek is pending */
|
|
#define BLB_user_def 64 /* Blob is user created */
|
|
#define BLB_large_scan 128 /* Blob is larger than page buffer cache */
|
|
|
|
/* Blob levels are:
|
|
|
|
0 small blob -- blob "record" is actual data
|
|
1 medium blob -- blob "record" is pointer to pages
|
|
2 large blob -- blob "record" is pointer to pages of pointers
|
|
*/
|
|
|
|
/* mapping blob ids for REPLAY */
|
|
class map : public pool_alloc<type_map>
|
|
{
|
|
public:
|
|
map *map_next;
|
|
blb *map_old_blob;
|
|
blb *map_new_blob;
|
|
};
|
|
typedef map *MAP;
|
|
|
|
#endif /* _JRD_BLB_H_ */
|