diff options
Diffstat (limited to 'db2/mp/mp_open.c')
| -rw-r--r-- | db2/mp/mp_open.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/db2/mp/mp_open.c b/db2/mp/mp_open.c new file mode 100644 index 0000000..257ce1b --- /dev/null +++ b/db2/mp/mp_open.c @@ -0,0 +1,176 @@ +/*- + * 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 10.12 (Sleepycat) 7/6/97"; +#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); + LOCKINIT(dbmp, &dbmp->mutex); + 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); + + /* + * 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. + */ + if (!F_ISSET(dbmp, MP_ISPRIVATE)) + F_SET(dbmp, MP_LOCKREGION); + if (LF_ISSET(DB_THREAD)) + F_SET(dbmp, MP_LOCKHANDLE | MP_LOCKREGION); + + *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; + + /* Close the region. */ + if ((t_ret = __memp_rclose(dbmp)) && ret == 0) + ret = t_ret; + + /* Free 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->mutex); + LIST_INSERT_HEAD(&dbmp->dbregq, mpr, q); + UNLOCKHANDLE(dbmp, &dbmp->mutex); + + return (0); +} |