qam.h

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1999-2005
 *      Sleepycat Software.  All rights reserved.
 *
 * $Id: qam.h,v 12.3 2005/10/16 18:42:40 bostic Exp $
 */

#ifndef _DB_QAM_H_
#define _DB_QAM_H_

/*
 * QAM data elements: a status field and the data.
 */
typedef struct _qamdata {
        u_int8_t  flags;        /* 00: delete bit. */
#define QAM_VALID       0x01
#define QAM_SET         0x02
        u_int8_t  data[1];      /* Record. */
} QAMDATA;

struct __queue;         typedef struct __queue QUEUE;
struct __qcursor;       typedef struct __qcursor QUEUE_CURSOR;

struct __qcursor {
        /* struct __dbc_internal */
        __DBC_INTERNAL

        /* Queue private part */

        /* Per-thread information: queue private. */
        db_recno_t       recno;         /* Current record number. */

        u_int32_t        flags;
};

typedef struct __mpfarray {
        u_int32_t n_extent;             /* Number of extents in table. */
        u_int32_t low_extent;           /* First extent open. */
        u_int32_t hi_extent;            /* Last extent open. */
        struct __qmpf {
                int pinref;
                DB_MPOOLFILE *mpf;
        } *mpfarray;                     /* Array of open extents. */
} MPFARRAY;

/*
 * The in-memory, per-tree queue data structure.
 */
struct __queue {
        db_pgno_t q_meta;               /* Database meta-data page. */
        db_pgno_t q_root;               /* Database root page. */

        int       re_pad;               /* Fixed-length padding byte. */
        u_int32_t re_len;               /* Length for fixed-length records. */
        u_int32_t rec_page;             /* records per page */
        u_int32_t page_ext;             /* Pages per extent */
        MPFARRAY array1, array2;        /* File arrays. */

                                        /* Extent file configuration: */
        DBT pgcookie;                   /* Initialized pgcookie. */
        DB_PGINFO pginfo;               /* Initialized pginfo struct. */

        char *path;                     /* Space allocated to file pathname. */
        char *name;                     /* The name of the file. */
        char *dir;                      /* The dir of the file. */
        int mode;                       /* Mode to open extents. */
};

/* Format for queue extent names. */
#define QUEUE_EXTENT            "%s%c__dbq.%s.%d"
#define QUEUE_EXTENT_HEAD       "__dbq.%s."

typedef struct __qam_filelist {
        DB_MPOOLFILE *mpf;
        u_int32_t id;
} QUEUE_FILELIST;

/*
 * Calculate the page number of a recno.
 *
 * Number of records per page =
 *      Divide the available space on the page by the record len + header.
 *
 * Page number for record =
 *      divide the physical record number by the records per page
 *      add the root page number
 *      For now the root page will always be 1, but we might want to change
 *      in the future (e.g. multiple fixed len queues per file).
 *
 * Index of record on page =
 *      physical record number, less the logical pno times records/page
 */
#define CALC_QAM_RECNO_PER_PAGE(dbp)                                    \
    (((dbp)->pgsize - QPAGE_SZ(dbp)) /                                  \
    (u_int32_t)DB_ALIGN((uintmax_t)SSZA(QAMDATA, data) +                \
    ((QUEUE *)(dbp)->q_internal)->re_len, sizeof(u_int32_t)))

#define QAM_RECNO_PER_PAGE(dbp) (((QUEUE*)(dbp)->q_internal)->rec_page)

#define QAM_RECNO_PAGE(dbp, recno)                                      \
    (((QUEUE *)(dbp)->q_internal)->q_root                               \
    + (((recno) - 1) / QAM_RECNO_PER_PAGE(dbp)))

#define QAM_PAGE_EXTENT(dbp, pgno)                                      \
    (((pgno) - 1) / ((QUEUE *)(dbp)->q_internal)->page_ext)

#define QAM_RECNO_EXTENT(dbp, recno)                                    \
    QAM_PAGE_EXTENT(dbp, QAM_RECNO_PAGE(dbp, recno))

#define QAM_RECNO_INDEX(dbp, pgno, recno)                               \
    (((recno) - 1) - (QAM_RECNO_PER_PAGE(dbp)                           \
    * (pgno - ((QUEUE *)(dbp)->q_internal)->q_root)))

#define QAM_GET_RECORD(dbp, page, index)                                \
    ((QAMDATA *)((u_int8_t *)(page) + (QPAGE_SZ(dbp) +                  \
    (DB_ALIGN((uintmax_t)SSZA(QAMDATA, data) +                          \
    ((QUEUE *)(dbp)->q_internal)->re_len, sizeof(u_int32_t)) * index))))

#define QAM_AFTER_CURRENT(meta, recno)                                  \
    ((recno) > (meta)->cur_recno &&                                     \
    ((meta)->first_recno <= (meta)->cur_recno ||                        \
    ((recno) < (meta)->first_recno &&                                   \
    (recno) - (meta)->cur_recno < (meta)->first_recno - (recno))))

#define QAM_BEFORE_FIRST(meta, recno)                                   \
    ((recno) < (meta)->first_recno &&                                   \
    ((meta->first_recno <= (meta)->cur_recno ||                         \
    ((recno) > (meta)->cur_recno &&                                     \
    (recno) - (meta)->cur_recno > (meta)->first_recno - (recno)))))

#define QAM_NOT_VALID(meta, recno)                                      \
    (recno == RECNO_OOB ||                                              \
        QAM_BEFORE_FIRST(meta, recno) || QAM_AFTER_CURRENT(meta, recno))

/*
 * Log opcodes for the mvptr routine.
 */
#define QAM_SETFIRST            0x01
#define QAM_SETCUR              0x02
#define QAM_TRUNCATE            0x04

/*
 * Parameter to __qam_position.
 */
typedef enum {
        QAM_READ,
        QAM_WRITE,
        QAM_CONSUME
} qam_position_mode;

typedef enum {
        QAM_PROBE_GET,
        QAM_PROBE_PUT,
        QAM_PROBE_MPF
} qam_probe_mode;

/*
 * Ops for __qam_nameop.
 */
typedef enum {
        QAM_NAME_DISCARD,
        QAM_NAME_RENAME,
        QAM_NAME_REMOVE
} qam_name_op;

#define __qam_fget(dbp, pgnoaddr, flags, addrp) \
        __qam_fprobe(dbp, *pgnoaddr, addrp, QAM_PROBE_GET, flags)

#define __qam_fput(dbp, pageno, addrp, flags) \
        __qam_fprobe(dbp, pageno, addrp, QAM_PROBE_PUT, flags)

#include "dbinc_auto/qam_auto.h"
#include "dbinc_auto/qam_ext.h"
#endif /* !_DB_QAM_H_ */

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