db/btree/bt_stat.c

	bt_stat.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996, 1997, 1998
 *  Sleepycat Software.  All rights reserved.
 */

#include "config.h"

#ifndef lint
static const char sccsid[] = "@(#)bt_stat.c 10.27 (Sleepycat) 11/25/98";
#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 "btree.h"

/*
 * __bam_stat --
 *  Gather/print the btree statistics
 *
 * PUBLIC: int __bam_stat __P((DB *, void *, void *(*)(size_t), u_int32_t));
 */
int
__bam_stat(dbp, spp, db_malloc, flags)
    DB *dbp;
    void *spp;
    void *(*db_malloc) __P((size_t));
    u_int32_t flags;
{
    BTMETA *meta;
    BTREE *t;
    DBC *dbc;
    DB_BTREE_STAT *sp;
    DB_LOCK lock;
    PAGE *h;
    db_pgno_t lastpgno, pgno;
    int ret, t_ret;

    DB_PANIC_CHECK(dbp);

    /* Check for invalid flags. */
    if ((ret = __db_statchk(dbp, flags)) != 0)
        return (ret);

    if ((ret = dbp->cursor(dbp, NULL, &dbc, 0)) != 0)
        return (ret);

    DEBUG_LWRITE(dbc, NULL, "bam_stat", NULL, NULL, flags);

    t = dbp->internal;

    if (spp == NULL)
        return (0);

    /* Allocate and clear the structure. */
    if ((ret = __os_malloc(sizeof(*sp), db_malloc, &sp)) != 0)
        goto err;
    memset(sp, 0, sizeof(*sp));

    /* If the app just wants the record count, make it fast. */
    if (flags == DB_RECORDCOUNT) {
        pgno = PGNO_ROOT;
        if ((ret = __bam_lget(dbc, 0, pgno, DB_LOCK_READ, &lock)) != 0)
            goto err;
        if ((ret = memp_fget(dbp->mpf, &pgno, 0, (PAGE **)&h)) != 0)
            goto err;

        sp->bt_nrecs = RE_NREC(h);

        (void)memp_fput(dbp->mpf, h, 0);
        (void)__BT_LPUT(dbc, lock);
        goto done;
    }

    /* Get the meta-data page. */
    pgno = PGNO_METADATA;
    if ((ret = __bam_lget(dbc, 0, pgno, DB_LOCK_READ, &lock)) != 0)
        goto err;
    if ((ret = memp_fget(dbp->mpf, &pgno, 0, (PAGE **)&meta)) != 0)
        goto err;

    /* Translate the metadata flags. */
    if (F_ISSET(meta, BTM_DUP))
        sp->bt_flags |= DB_DUP;
    if (F_ISSET(meta, BTM_FIXEDLEN))
        sp->bt_flags |= DB_FIXEDLEN;
    if (F_ISSET(meta, BTM_RECNUM))
        sp->bt_flags |= DB_RECNUM;
    if (F_ISSET(meta, BTM_RENUMBER))
        sp->bt_flags |= DB_RENUMBER;

    /* Get the remaining metadata fields. */
    sp->bt_minkey = meta->minkey;
    sp->bt_maxkey = meta->maxkey;
    sp->bt_re_len = meta->re_len;
    sp->bt_re_pad = meta->re_pad;
    sp->bt_magic = meta->magic;
    sp->bt_version = meta->version;

    /* Get the page size from the DB. */
    sp->bt_pagesize = dbp->pgsize;

    /* Walk the free list, counting pages. */
    for (sp->bt_free = 0, pgno = meta->free; pgno != PGNO_INVALID;) {
        ++sp->bt_free;

        if ((ret = memp_fget(dbp->mpf, &pgno, 0, &h)) != 0) {
            (void)memp_fput(dbp->mpf, meta, 0);
            (void)__BT_TLPUT(dbc, lock);
            goto err;
        }
        pgno = h->next_pgno;
        (void)memp_fput(dbp->mpf, h, 0);
    }

    /* Discard the meta-data page. */
    (void)memp_fput(dbp->mpf, meta, 0);
    (void)__BT_TLPUT(dbc, lock);

    /* Determine the last page of the database. */
    if ((ret = memp_fget(dbp->mpf, &lastpgno, DB_MPOOL_LAST, &h)) != 0)
        goto err;
    (void)memp_fput(dbp->mpf, h, 0);

    /* Get the root page. */
    pgno = PGNO_ROOT;
    if ((ret = __bam_lget(dbc, 0, PGNO_ROOT, DB_LOCK_READ, &lock)) != 0)
        goto err;
    if ((ret = memp_fget(dbp->mpf, &pgno, 0, &h)) != 0) {
        (void)__BT_LPUT(dbc, lock);
        goto err;
    }

    /* Get the levels from the root page. */
    sp->bt_levels = h->level;

    /* Walk the page list, counting things. */
    for (;;) {
        switch (TYPE(h)) {
        case P_INVALID:
            break;
        case P_IBTREE:
        case P_IRECNO:
            ++sp->bt_int_pg;
            sp->bt_int_pgfree += HOFFSET(h) - LOFFSET(h);
            break;
        case P_LBTREE:
            ++sp->bt_leaf_pg;
            sp->bt_leaf_pgfree += HOFFSET(h) - LOFFSET(h);
            sp->bt_nrecs += NUM_ENT(h) / P_INDX;
            break;
        case P_LRECNO:
            ++sp->bt_leaf_pg;
            sp->bt_leaf_pgfree += HOFFSET(h) - LOFFSET(h);
            sp->bt_nrecs += NUM_ENT(h);
            break;
        case P_DUPLICATE:
            ++sp->bt_dup_pg;
            /* XXX MARGO: sp->bt_dup_pgfree; */
            break;
        case P_OVERFLOW:
            ++sp->bt_over_pg;
            /* XXX MARGO: sp->bt_over_pgfree; */
            break;
        default:
            (void)memp_fput(dbp->mpf, h, 0);
            (void)__BT_LPUT(dbc, lock);
            return (__db_pgfmt(dbp, pgno));
        }

        (void)memp_fput(dbp->mpf, h, 0);
        (void)__BT_LPUT(dbc, lock);

        if (++pgno > lastpgno)
            break;
        if (__bam_lget(dbc, 0, pgno, DB_LOCK_READ, &lock))
            break;
        if (memp_fget(dbp->mpf, &pgno, 0, &h) != 0) {
            (void)__BT_LPUT(dbc, lock);
            break;
        }
    }

done:   *(DB_BTREE_STAT **)spp = sp;
    ret = 0;

err:    if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0)
        ret = t_ret;
    return (ret);
}