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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996, 1997
* Sleepycat Software. All rights reserved.
*/
#include "config.h"
#ifndef lint
static const char sccsid[] = "@(#)mp_open.c 10.13 (Sleepycat) 9/23/97";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#endif
#include "db_int.h"
#include "shqueue.h"
#include "db_shash.h"
#include "mp.h"
#include "common_ext.h"
/*
* memp_open --
* Initialize and/or join a memory pool.
*/
int
memp_open(path, flags, mode, dbenv, retp)
const char *path;
int flags, mode;
DB_ENV *dbenv;
DB_MPOOL **retp;
{
DB_MPOOL *dbmp;
size_t cachesize;
int ret;
/* Validate arguments. */
#ifdef HAVE_SPINLOCKS
#define OKFLAGS (DB_CREATE | DB_MPOOL_PRIVATE | DB_NOMMAP | DB_THREAD)
#else
#define OKFLAGS (DB_CREATE | DB_MPOOL_PRIVATE | DB_NOMMAP)
#endif
if ((ret = __db_fchk(dbenv, "memp_open", flags, OKFLAGS)) != 0)
return (ret);
/* Extract fields from DB_ENV structure. */
cachesize = dbenv == NULL ? 0 : dbenv->mp_size;
/* Create and initialize the DB_MPOOL structure. */
if ((dbmp = (DB_MPOOL *)calloc(1, sizeof(DB_MPOOL))) == NULL)
return (ENOMEM);
LIST_INIT(&dbmp->dbregq);
TAILQ_INIT(&dbmp->dbmfq);
dbmp->dbenv = dbenv;
/* Decide if it's possible for anyone else to access the pool. */
if ((dbenv == NULL && path == NULL) ||
(dbenv != NULL && F_ISSET(dbenv, DB_MPOOL_PRIVATE)))
F_SET(dbmp, MP_ISPRIVATE);
/*
* XXX
* HP-UX won't permit mutexes to live in anything but shared memory.
* So, we have to instantiate the shared mpool region file on that
* architecture, regardless. If this turns out to be a performance
* problem, we could probably use anonymous memory instead.
*/
#if defined(__hppa)
F_CLR(dbmp, MP_ISPRIVATE);
#endif
/*
* Map in the region. We do locking regardless, as portions of it are
* implemented in common code (if we put the region in a file, that is).
*/
F_SET(dbmp, MP_LOCKREGION);
if ((ret = __memp_ropen(dbmp, path, cachesize, mode, flags)) != 0)
goto err;
F_CLR(dbmp, MP_LOCKREGION);
/*
* If there's concurrent access, then we have to lock the region.
* If it's threaded, then we have to lock both the handles and the
* region, and we need to allocate a mutex for that purpose.
*/
if (!F_ISSET(dbmp, MP_ISPRIVATE))
F_SET(dbmp, MP_LOCKREGION);
if (LF_ISSET(DB_THREAD)) {
F_SET(dbmp, MP_LOCKHANDLE | MP_LOCKREGION);
LOCKREGION(dbmp);
ret = __memp_ralloc(dbmp,
sizeof(db_mutex_t), NULL, &dbmp->mutexp);
UNLOCKREGION(dbmp);
if (ret != 0) {
(void)memp_close(dbmp);
goto err;
}
LOCKINIT(dbmp, dbmp->mutexp);
}
*retp = dbmp;
return (0);
err: if (dbmp != NULL)
FREE(dbmp, sizeof(DB_MPOOL));
return (ret);
}
/*
* memp_close --
* Close a memory pool.
*/
int
memp_close(dbmp)
DB_MPOOL *dbmp;
{
DB_MPOOLFILE *dbmfp;
DB_MPREG *mpreg;
int ret, t_ret;
ret = 0;
/* Discard DB_MPREGs. */
while ((mpreg = LIST_FIRST(&dbmp->dbregq)) != NULL) {
LIST_REMOVE(mpreg, q);
FREE(mpreg, sizeof(DB_MPREG));
}
/* Discard DB_MPOOLFILEs. */
while ((dbmfp = TAILQ_FIRST(&dbmp->dbmfq)) != NULL)
if ((t_ret = memp_fclose(dbmfp)) != 0 && ret == 0)
ret = t_ret;
/* Discard thread mutex. */
if (F_ISSET(dbmp, MP_LOCKHANDLE)) {
LOCKREGION(dbmp);
__db_shalloc_free(dbmp->addr, dbmp->mutexp);
UNLOCKREGION(dbmp);
}
/* Close the region. */
if ((t_ret = __memp_rclose(dbmp)) && ret == 0)
ret = t_ret;
/* Discard the structure. */
FREE(dbmp, sizeof(DB_MPOOL));
return (ret);
}
/*
* memp_unlink --
* Exit a memory pool.
*/
int
memp_unlink(path, force, dbenv)
const char *path;
int force;
DB_ENV *dbenv;
{
return (__db_runlink(dbenv,
DB_APP_NONE, path, DB_DEFAULT_MPOOL_FILE, force));
}
/*
* memp_register --
* Register a file type's pgin, pgout routines.
*/
int
memp_register(dbmp, ftype, pgin, pgout)
DB_MPOOL *dbmp;
int ftype;
int (*pgin) __P((db_pgno_t, void *, DBT *));
int (*pgout) __P((db_pgno_t, void *, DBT *));
{
DB_MPREG *mpr;
if ((mpr = (DB_MPREG *)malloc(sizeof(DB_MPREG))) == NULL)
return (ENOMEM);
mpr->ftype = ftype;
mpr->pgin = pgin;
mpr->pgout = pgout;
/*
* Insert at the head. Because we do a linear walk, we'll find
* the most recent registry in the case of multiple entries, so
* we don't have to check for multiple registries.
*/
LOCKHANDLE(dbmp, dbmp->mutexp);
LIST_INSERT_HEAD(&dbmp->dbregq, mpr, q);
UNLOCKHANDLE(dbmp, dbmp->mutexp);
return (0);
}
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