diff options
Diffstat (limited to 'db2/btree/bt_recno.c')
| -rw-r--r-- | db2/btree/bt_recno.c | 1356 |
1 files changed, 0 insertions, 1356 deletions
diff --git a/db2/btree/bt_recno.c b/db2/btree/bt_recno.c deleted file mode 100644 index c69877ff7f..0000000000 --- a/db2/btree/bt_recno.c +++ /dev/null @@ -1,1356 +0,0 @@ -/*- - * See the file LICENSE for redistribution information. - * - * Copyright (c) 1997, 1998 - * Sleepycat Software. All rights reserved. - */ - -#include "config.h" - -#ifndef lint -static const char sccsid[] = "@(#)bt_recno.c 10.53 (Sleepycat) 12/11/98"; -#endif /* not lint */ - -#ifndef NO_SYSTEM_INCLUDES -#include <sys/types.h> - -#include <errno.h> -#include <limits.h> -#include <string.h> -#endif - -#include "db_int.h" -#include "db_page.h" -#include "btree.h" -#include "db_ext.h" -#include "shqueue.h" -#include "db_shash.h" -#include "lock.h" -#include "lock_ext.h" - -static int __ram_add __P((DBC *, db_recno_t *, DBT *, u_int32_t, u_int32_t)); -static int __ram_delete __P((DB *, DB_TXN *, DBT *, u_int32_t)); -static int __ram_fmap __P((DBC *, db_recno_t)); -static int __ram_i_delete __P((DBC *)); -static int __ram_put __P((DB *, DB_TXN *, DBT *, DBT *, u_int32_t)); -static int __ram_source __P((DB *, RECNO *, const char *)); -static int __ram_sync __P((DB *, u_int32_t)); -static int __ram_update __P((DBC *, db_recno_t, int)); -static int __ram_vmap __P((DBC *, db_recno_t)); -static int __ram_writeback __P((DBC *)); - -/* - * In recno, there are two meanings to the on-page "deleted" flag. If we're - * re-numbering records, it means the record was implicitly created. We skip - * over implicitly created records if doing a cursor "next" or "prev", and - * return DB_KEYEMPTY if they're explicitly requested.. If not re-numbering - * records, it means that the record was implicitly created, or was deleted. - * We skip over implicitly created or deleted records if doing a cursor "next" - * or "prev", and return DB_KEYEMPTY if they're explicitly requested. - * - * If we're re-numbering records, then we have to detect in the cursor that - * a record was deleted, and adjust the cursor as necessary on the next get. - * If we're not re-numbering records, then we can detect that a record has - * been deleted by looking at the actual on-page record, so we completely - * ignore the cursor's delete flag. This is different from the B+tree code. - * It also maintains whether the cursor references a deleted record in the - * cursor, and it doesn't always check the on-page value. - */ -#define CD_SET(dbp, cp) { \ - if (F_ISSET(dbp, DB_RE_RENUMBER)) \ - F_SET(cp, C_DELETED); \ -} -#define CD_CLR(dbp, cp) { \ - if (F_ISSET(dbp, DB_RE_RENUMBER)) \ - F_CLR(cp, C_DELETED); \ -} -#define CD_ISSET(dbp, cp) \ - (F_ISSET(dbp, DB_RE_RENUMBER) && F_ISSET(cp, C_DELETED)) - -/* - * __ram_open -- - * Recno open function. - * - * PUBLIC: int __ram_open __P((DB *, DB_INFO *)); - */ -int -__ram_open(dbp, dbinfo) - DB *dbp; - DB_INFO *dbinfo; -{ - BTREE *t; - DBC *dbc; - RECNO *rp; - int ret, t_ret; - - /* Allocate and initialize the private btree structure. */ - if ((ret = __os_calloc(1, sizeof(BTREE), &t)) != 0) - return (ret); - dbp->internal = t; - __bam_setovflsize(dbp); - - /* Allocate and initialize the private recno structure. */ - if ((ret = __os_calloc(1, sizeof(*rp), &rp)) != 0) - return (ret); - /* Link in the private recno structure. */ - t->recno = rp; - - /* - * Intention is to make sure all of the user's selections are okay - * here and then use them without checking. - */ - if (dbinfo == NULL) { - rp->re_delim = '\n'; - rp->re_pad = ' '; - rp->re_fd = -1; - F_SET(rp, RECNO_EOF); - } else { - /* - * If the user specified a source tree, open it and map it in. - * - * !!! - * We don't complain if the user specified transactions or - * threads. It's possible to make it work, but you'd better - * know what you're doing! - */ - if (dbinfo->re_source == NULL) { - rp->re_fd = -1; - F_SET(rp, RECNO_EOF); - } else { - if ((ret = - __ram_source(dbp, rp, dbinfo->re_source)) != 0) - goto err; - } - - /* Copy delimiter, length and padding values. */ - rp->re_delim = - F_ISSET(dbp, DB_RE_DELIMITER) ? dbinfo->re_delim : '\n'; - rp->re_pad = F_ISSET(dbp, DB_RE_PAD) ? dbinfo->re_pad : ' '; - - if (F_ISSET(dbp, DB_RE_FIXEDLEN)) { - if ((rp->re_len = dbinfo->re_len) == 0) { - __db_err(dbp->dbenv, - "record length must be greater than 0"); - ret = EINVAL; - goto err; - } - } else - rp->re_len = 0; - } - - /* Initialize the remaining fields/methods of the DB. */ - dbp->am_close = __ram_close; - dbp->del = __ram_delete; - dbp->put = __ram_put; - dbp->stat = __bam_stat; - dbp->sync = __ram_sync; - - /* Start up the tree. */ - if ((ret = __bam_read_root(dbp)) != 0) - goto err; - - /* Set the overflow page size. */ - __bam_setovflsize(dbp); - - /* If we're snapshotting an underlying source file, do it now. */ - if (dbinfo != NULL && F_ISSET(dbinfo, DB_SNAPSHOT)) { - /* Allocate a cursor. */ - if ((ret = dbp->cursor(dbp, NULL, &dbc, 0)) != 0) - goto err; - - /* Do the snapshot. */ - if ((ret = __ram_update(dbc, - DB_MAX_RECORDS, 0)) != 0 && ret == DB_NOTFOUND) - ret = 0; - - /* Discard the cursor. */ - if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0) - ret = t_ret; - - if (ret != 0) - goto err; - } - - return (0); - -err: /* If we mmap'd a source file, discard it. */ - if (rp->re_smap != NULL) - (void)__db_unmapfile(rp->re_smap, rp->re_msize); - - /* If we opened a source file, discard it. */ - if (rp->re_fd != -1) - (void)__os_close(rp->re_fd); - if (rp->re_source != NULL) - __os_freestr(rp->re_source); - - __os_free(rp, sizeof(*rp)); - - return (ret); -} - -/* - * __ram_delete -- - * Recno db->del function. - */ -static int -__ram_delete(dbp, txn, key, flags) - DB *dbp; - DB_TXN *txn; - DBT *key; - u_int32_t flags; -{ - CURSOR *cp; - DBC *dbc; - db_recno_t recno; - int ret, t_ret; - - DB_PANIC_CHECK(dbp); - - /* Check for invalid flags. */ - if ((ret = __db_delchk(dbp, - key, flags, F_ISSET(dbp, DB_AM_RDONLY))) != 0) - return (ret); - - /* Acquire a cursor. */ - if ((ret = dbp->cursor(dbp, txn, &dbc, DB_WRITELOCK)) != 0) - return (ret); - - DEBUG_LWRITE(dbc, txn, "ram_delete", key, NULL, flags); - - /* Check the user's record number and fill in as necessary. */ - if ((ret = __ram_getno(dbc, key, &recno, 0)) != 0) - goto err; - - /* Do the delete. */ - cp = dbc->internal; - cp->recno = recno; - ret = __ram_i_delete(dbc); - - /* Release the cursor. */ -err: if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0) - ret = t_ret; - - return (ret); -} - -/* - * __ram_i_delete -- - * Internal version of recno delete, called by __ram_delete and - * __ram_c_del. - */ -static int -__ram_i_delete(dbc) - DBC *dbc; -{ - BKEYDATA bk; - BTREE *t; - CURSOR *cp; - DB *dbp; - DBT hdr, data; - PAGE *h; - db_indx_t indx; - int exact, ret, stack; - - dbp = dbc->dbp; - cp = dbc->internal; - t = dbp->internal; - stack = 0; - - /* - * If this is CDB and this isn't a write cursor, then it's an error. - * If it is a write cursor, but we don't yet hold the write lock, then - * we need to upgrade to the write lock. - */ - if (F_ISSET(dbp, DB_AM_CDB)) { - /* Make sure it's a valid update cursor. */ - if (!F_ISSET(dbc, DBC_RMW | DBC_WRITER)) - return (EINVAL); - - if (F_ISSET(dbc, DBC_RMW) && - (ret = lock_get(dbp->dbenv->lk_info, dbc->locker, - DB_LOCK_UPGRADE, &dbc->lock_dbt, DB_LOCK_WRITE, - &dbc->mylock)) != 0) - return (EAGAIN); - } - - /* Search the tree for the key; delete only deletes exact matches. */ - if ((ret = __bam_rsearch(dbc, &cp->recno, S_DELETE, 1, &exact)) != 0) - goto err; - if (!exact) { - ret = DB_NOTFOUND; - goto err; - } - stack = 1; - - h = cp->csp->page; - indx = cp->csp->indx; - - /* - * If re-numbering records, the on-page deleted flag can only mean - * that this record was implicitly created. Applications aren't - * permitted to delete records they never created, return an error. - * - * If not re-numbering records, the on-page deleted flag means that - * this record was implicitly created, or, was deleted at some time. - * The former is an error because applications aren't permitted to - * delete records they never created, the latter is an error because - * if the record was "deleted", we could never have found it. - */ - if (B_DISSET(GET_BKEYDATA(h, indx)->type)) { - ret = DB_KEYEMPTY; - goto err; - } - - if (F_ISSET(dbp, DB_RE_RENUMBER)) { - /* Delete the item, adjust the counts, adjust the cursors. */ - if ((ret = __bam_ditem(dbc, h, indx)) != 0) - goto err; - __bam_adjust(dbc, -1); - __ram_ca(dbp, cp->recno, CA_DELETE); - - /* - * If the page is empty, delete it. The whole tree is locked - * so there are no preparations to make. - */ - if (NUM_ENT(h) == 0 && h->pgno != PGNO_ROOT) { - stack = 0; - ret = __bam_dpages(dbc); - } - } else { - /* Use a delete/put pair to replace the record with a marker. */ - if ((ret = __bam_ditem(dbc, h, indx)) != 0) - goto err; - - B_TSET(bk.type, B_KEYDATA, 1); - bk.len = 0; - memset(&hdr, 0, sizeof(hdr)); - hdr.data = &bk; - hdr.size = SSZA(BKEYDATA, data); - memset(&data, 0, sizeof(data)); - data.data = (char *)""; - data.size = 0; - if ((ret = __db_pitem(dbc, - h, indx, BKEYDATA_SIZE(0), &hdr, &data)) != 0) - goto err; - } - F_SET(t->recno, RECNO_MODIFIED); - -err: if (stack) - __bam_stkrel(dbc, 0); - - /* If we upgraded the CDB lock upon entry; downgrade it now. */ - if (F_ISSET(dbp, DB_AM_CDB) && F_ISSET(dbc, DBC_RMW)) - (void)__lock_downgrade(dbp->dbenv->lk_info, dbc->mylock, - DB_LOCK_IWRITE, 0); - return (ret); -} - -/* - * __ram_put -- - * Recno db->put function. - */ -static int -__ram_put(dbp, txn, key, data, flags) - DB *dbp; - DB_TXN *txn; - DBT *key, *data; - u_int32_t flags; -{ - DBC *dbc; - db_recno_t recno; - int ret, t_ret; - - DB_PANIC_CHECK(dbp); - - /* Check for invalid flags. */ - if ((ret = __db_putchk(dbp, - key, data, flags, F_ISSET(dbp, DB_AM_RDONLY), 0)) != 0) - return (ret); - - /* Allocate a cursor. */ - if ((ret = dbp->cursor(dbp, txn, &dbc, DB_WRITELOCK)) != 0) - return (ret); - - DEBUG_LWRITE(dbc, txn, "ram_put", key, data, flags); - - /* - * If we're appending to the tree, make sure we've read in all of - * the backing source file. Otherwise, check the user's record - * number and fill in as necessary. - */ - ret = flags == DB_APPEND ? - __ram_update(dbc, DB_MAX_RECORDS, 0) : - __ram_getno(dbc, key, &recno, 1); - - /* Add the record. */ - if (ret == 0) - ret = __ram_add(dbc, &recno, data, flags, 0); - - /* Discard the cursor. */ - if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0) - ret = t_ret; - - /* Return the record number if we're appending to the tree. */ - if (ret == 0 && flags == DB_APPEND) - *(db_recno_t *)key->data = recno; - - return (ret); -} - -/* - * __ram_sync -- - * Recno db->sync function. - */ -static int -__ram_sync(dbp, flags) - DB *dbp; - u_int32_t flags; -{ - DBC *dbc; - int ret, t_ret; - - /* - * Sync the underlying btree. - * - * !!! - * We don't need to do a panic check or flags check, the "real" - * sync function does all that for us. - */ - if ((ret = __db_sync(dbp, flags)) != 0) - return (ret); - - /* Allocate a cursor. */ - if ((ret = dbp->cursor(dbp, NULL, &dbc, 0)) != 0) - return (ret); - - DEBUG_LWRITE(dbc, NULL, "ram_sync", NULL, NULL, flags); - - /* Copy back the backing source file. */ - ret = __ram_writeback(dbc); - - /* Discard the cursor. */ - if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0) - ret = t_ret; - - return (ret); -} - -/* - * __ram_close -- - * Recno db->close function. - * - * PUBLIC: int __ram_close __P((DB *)); - */ -int -__ram_close(dbp) - DB *dbp; -{ - RECNO *rp; - - rp = ((BTREE *)dbp->internal)->recno; - - /* Close any underlying mmap region. */ - if (rp->re_smap != NULL) - (void)__db_unmapfile(rp->re_smap, rp->re_msize); - - /* Close any backing source file descriptor. */ - if (rp->re_fd != -1) - (void)__os_close(rp->re_fd); - - /* Free any backing source file name. */ - if (rp->re_source != NULL) - __os_freestr(rp->re_source); - - /* Free allocated memory. */ - __os_free(rp, sizeof(RECNO)); - ((BTREE *)dbp->internal)->recno = NULL; - - /* Close the underlying btree. */ - return (__bam_close(dbp)); -} - -/* - * __ram_c_del -- - * Recno cursor->c_del function. - * - * PUBLIC: int __ram_c_del __P((DBC *, u_int32_t)); - */ -int -__ram_c_del(dbc, flags) - DBC *dbc; - u_int32_t flags; -{ - CURSOR *cp; - DB *dbp; - int ret; - - dbp = dbc->dbp; - cp = dbc->internal; - - DB_PANIC_CHECK(dbp); - - /* Check for invalid flags. */ - if ((ret = __db_cdelchk(dbp, flags, - F_ISSET(dbp, DB_AM_RDONLY), cp->recno != RECNO_OOB)) != 0) - return (ret); - - DEBUG_LWRITE(dbc, dbc->txn, "ram_c_del", NULL, NULL, flags); - - /* - * If we are running CDB, this had better be either a write - * cursor or an immediate writer. - */ - if (F_ISSET(dbp, DB_AM_CDB)) - if (!F_ISSET(dbc, DBC_RMW | DBC_WRITER)) - return (EINVAL); - - /* - * The semantics of cursors during delete are as follows: if record - * numbers are mutable (DB_RE_RENUMBER is set), deleting a record - * causes the cursor to automatically point to the record immediately - * following. In this case it is possible to use a single cursor for - * repeated delete operations, without intervening operations. - * - * If record numbers are not mutable, then records are replaced with - * a marker containing a delete flag. If the record referenced by - * this cursor has already been deleted, we will detect that as part - * of the delete operation, and fail. - */ - return (__ram_i_delete(dbc)); -} - -/* - * __ram_c_get -- - * Recno cursor->c_get function. - * - * PUBLIC: int __ram_c_get __P((DBC *, DBT *, DBT *, u_int32_t)); - */ -int -__ram_c_get(dbc, key, data, flags) - DBC *dbc; - DBT *key, *data; - u_int32_t flags; -{ - CURSOR *cp, copy; - DB *dbp; - PAGE *h; - db_indx_t indx; - int exact, ret, stack, tmp_rmw; - - dbp = dbc->dbp; - cp = dbc->internal; - - DB_PANIC_CHECK(dbp); - - /* Check for invalid flags. */ - if ((ret = __db_cgetchk(dbc->dbp, - key, data, flags, cp->recno != RECNO_OOB)) != 0) - return (ret); - - /* Clear OR'd in additional bits so we can check for flag equality. */ - tmp_rmw = 0; - if (LF_ISSET(DB_RMW)) { - if (!F_ISSET(dbp, DB_AM_CDB)) { - tmp_rmw = 1; - F_SET(dbc, DBC_RMW); - } - LF_CLR(DB_RMW); - } - - DEBUG_LREAD(dbc, dbc->txn, "ram_c_get", - flags == DB_SET || flags == DB_SET_RANGE ? key : NULL, NULL, flags); - - /* Initialize the cursor for a new retrieval. */ - copy = *cp; - -retry: /* Update the record number. */ - stack = 0; - switch (flags) { - case DB_CURRENT: - /* - * If record numbers are mutable: if we just deleted a record, - * there is no action necessary, we return the record following - * the deleted item by virtue of renumbering the tree. - */ - break; - case DB_NEXT: - /* - * If record numbers are mutable: if we just deleted a record, - * we have to avoid incrementing the record number so that we - * return the right record by virtue of renumbering the tree. - */ - if (CD_ISSET(dbp, cp)) - break; - - if (cp->recno != RECNO_OOB) { - ++cp->recno; - break; - } - /* FALLTHROUGH */ - case DB_FIRST: - flags = DB_NEXT; - cp->recno = 1; - break; - case DB_PREV: - if (cp->recno != RECNO_OOB) { - if (cp->recno == 1) { - ret = DB_NOTFOUND; - goto err; - } - --cp->recno; - break; - } - /* FALLTHROUGH */ - case DB_LAST: - flags = DB_PREV; - if (((ret = __ram_update(dbc, - DB_MAX_RECORDS, 0)) != 0) && ret != DB_NOTFOUND) - goto err; - if ((ret = __bam_nrecs(dbc, &cp->recno)) != 0) - goto err; - if (cp->recno == 0) { - ret = DB_NOTFOUND; - goto err; - } - break; - case DB_SET: - case DB_SET_RANGE: - if ((ret = __ram_getno(dbc, key, &cp->recno, 0)) != 0) - goto err; - break; - } - - /* Return the key if the user didn't give us one. */ - if (flags != DB_SET && flags != DB_SET_RANGE && - (ret = __db_retcopy(key, &cp->recno, sizeof(cp->recno), - &dbc->rkey.data, &dbc->rkey.ulen, dbp->db_malloc)) != 0) - goto err; - - /* Search the tree for the record. */ - if ((ret = __bam_rsearch(dbc, &cp->recno, - F_ISSET(dbc, DBC_RMW) ? S_FIND_WR : S_FIND, 1, &exact)) != 0) - goto err; - stack = 1; - if (!exact) { - ret = DB_NOTFOUND; - goto err; - } - h = cp->csp->page; - indx = cp->csp->indx; - - /* - * If re-numbering records, the on-page deleted flag means this record - * was implicitly created. If not re-numbering records, the on-page - * deleted flag means this record was implicitly created, or, it was - * deleted at some time. Regardless, we skip such records if doing - * cursor next/prev operations, and fail if the application requested - * them explicitly. - */ - if (B_DISSET(GET_BKEYDATA(h, indx)->type)) { - if (flags == DB_NEXT || flags == DB_PREV) { - (void)__bam_stkrel(dbc, 0); - goto retry; - } - ret = DB_KEYEMPTY; - goto err; - } - - /* Return the data item. */ - if ((ret = __db_ret(dbp, - h, indx, data, &dbc->rdata.data, &dbc->rdata.ulen)) != 0) - goto err; - - /* The cursor was reset, no further delete adjustment is necessary. */ - CD_CLR(dbp, cp); - -err: if (stack) - (void)__bam_stkrel(dbc, 0); - - /* Release temporary lock upgrade. */ - if (tmp_rmw) - F_CLR(dbc, DBC_RMW); - - if (ret != 0) - *cp = copy; - - return (ret); -} - -/* - * __ram_c_put -- - * Recno cursor->c_put function. - * - * PUBLIC: int __ram_c_put __P((DBC *, DBT *, DBT *, u_int32_t)); - */ -int -__ram_c_put(dbc, key, data, flags) - DBC *dbc; - DBT *key, *data; - u_int32_t flags; -{ - CURSOR *cp, copy; - DB *dbp; - int exact, ret; - void *arg; - - dbp = dbc->dbp; - cp = dbc->internal; - - DB_PANIC_CHECK(dbp); - - if ((ret = __db_cputchk(dbc->dbp, key, data, flags, - F_ISSET(dbc->dbp, DB_AM_RDONLY), cp->recno != RECNO_OOB)) != 0) - return (ret); - - DEBUG_LWRITE(dbc, dbc->txn, "ram_c_put", NULL, data, flags); - - /* - * If we are running CDB, this had better be either a write - * cursor or an immediate writer. If it's a regular writer, - * that means we have an IWRITE lock and we need to upgrade - * it to a write lock. - */ - if (F_ISSET(dbp, DB_AM_CDB)) { - if (!F_ISSET(dbc, DBC_RMW | DBC_WRITER)) - return (EINVAL); - - if (F_ISSET(dbc, DBC_RMW) && - (ret = lock_get(dbp->dbenv->lk_info, dbc->locker, - DB_LOCK_UPGRADE, &dbc->lock_dbt, DB_LOCK_WRITE, - &dbc->mylock)) != 0) - return (EAGAIN); - } - - /* Initialize the cursor for a new retrieval. */ - copy = *cp; - - /* - * To split, we need a valid key for the page. Since it's a cursor, - * we have to build one. - * - * The split code discards all short-term locks and stack pages. - */ - if (0) { -split: arg = &cp->recno; - if ((ret = __bam_split(dbc, arg)) != 0) - goto err; - } - - if ((ret = __bam_rsearch(dbc, &cp->recno, S_INSERT, 1, &exact)) != 0) - goto err; - if (!exact) { - ret = DB_NOTFOUND; - goto err; - } - if ((ret = __bam_iitem(dbc, &cp->csp->page, - &cp->csp->indx, key, data, flags, 0)) == DB_NEEDSPLIT) { - if ((ret = __bam_stkrel(dbc, 0)) != 0) - goto err; - goto split; - } - if ((ret = __bam_stkrel(dbc, 0)) != 0) - goto err; - - switch (flags) { - case DB_AFTER: - /* Adjust the cursors. */ - __ram_ca(dbp, cp->recno, CA_IAFTER); - - /* Set this cursor to reference the new record. */ - cp->recno = copy.recno + 1; - break; - case DB_BEFORE: - /* Adjust the cursors. */ - __ram_ca(dbp, cp->recno, CA_IBEFORE); - - /* Set this cursor to reference the new record. */ - cp->recno = copy.recno; - break; - } - - /* The cursor was reset, no further delete adjustment is necessary. */ - CD_CLR(dbp, cp); - -err: if (F_ISSET(dbp, DB_AM_CDB) && F_ISSET(dbc, DBC_RMW)) - (void)__lock_downgrade(dbp->dbenv->lk_info, dbc->mylock, - DB_LOCK_IWRITE, 0); - - if (ret != 0) - *cp = copy; - - return (ret); -} - -/* - * __ram_ca -- - * Adjust cursors. - * - * PUBLIC: void __ram_ca __P((DB *, db_recno_t, ca_recno_arg)); - */ -void -__ram_ca(dbp, recno, op) - DB *dbp; - db_recno_t recno; - ca_recno_arg op; -{ - CURSOR *cp; - DBC *dbc; - - /* - * Adjust the cursors. See the comment in __bam_ca_delete(). - */ - DB_THREAD_LOCK(dbp); - for (dbc = TAILQ_FIRST(&dbp->active_queue); - dbc != NULL; dbc = TAILQ_NEXT(dbc, links)) { - cp = dbc->internal; - switch (op) { - case CA_DELETE: - if (recno > cp->recno) - --cp->recno; - if (recno == cp->recno) - CD_SET(dbp, cp); - break; - case CA_IAFTER: - if (recno > cp->recno) - ++cp->recno; - break; - case CA_IBEFORE: - if (recno >= cp->recno) - ++cp->recno; - break; - } - } - DB_THREAD_UNLOCK(dbp); -} - -/* - * __ram_getno -- - * Check the user's record number, and make sure we've seen it. - * - * PUBLIC: int __ram_getno __P((DBC *, const DBT *, db_recno_t *, int)); - */ -int -__ram_getno(dbc, key, rep, can_create) - DBC *dbc; - const DBT *key; - db_recno_t *rep; - int can_create; -{ - DB *dbp; - db_recno_t recno; - - dbp = dbc->dbp; - - /* Check the user's record number. */ - if ((recno = *(db_recno_t *)key->data) == 0) { - __db_err(dbp->dbenv, "illegal record number of 0"); - return (EINVAL); - } - if (rep != NULL) - *rep = recno; - - /* - * Btree can neither create records nor read them in. Recno can - * do both, see if we can find the record. - */ - return (dbp->type == DB_RECNO ? - __ram_update(dbc, recno, can_create) : 0); -} - -/* - * __ram_update -- - * Ensure the tree has records up to and including the specified one. - */ -static int -__ram_update(dbc, recno, can_create) - DBC *dbc; - db_recno_t recno; - int can_create; -{ - BTREE *t; - DB *dbp; - RECNO *rp; - db_recno_t nrecs; - int ret; - - dbp = dbc->dbp; - t = dbp->internal; - rp = t->recno; - - /* - * If we can't create records and we've read the entire backing input - * file, we're done. - */ - if (!can_create && F_ISSET(rp, RECNO_EOF)) - return (0); - - /* - * If we haven't seen this record yet, try to get it from the original - * file. - */ - if ((ret = __bam_nrecs(dbc, &nrecs)) != 0) - return (ret); - if (!F_ISSET(rp, RECNO_EOF) && recno > nrecs) { - if ((ret = rp->re_irec(dbc, recno)) != 0) - return (ret); - if ((ret = __bam_nrecs(dbc, &nrecs)) != 0) - return (ret); - } - - /* - * If we can create records, create empty ones up to the requested - * record. - */ - if (!can_create || recno <= nrecs + 1) - return (0); - - dbc->rdata.dlen = 0; - dbc->rdata.doff = 0; - dbc->rdata.flags = 0; - if (F_ISSET(dbp, DB_RE_FIXEDLEN)) { - if (dbc->rdata.ulen < rp->re_len) { - if ((ret = - __os_realloc(&dbc->rdata.data, rp->re_len)) != 0) { - dbc->rdata.ulen = 0; - dbc->rdata.data = NULL; - return (ret); - } - dbc->rdata.ulen = rp->re_len; - } - dbc->rdata.size = rp->re_len; - memset(dbc->rdata.data, rp->re_pad, rp->re_len); - } else - dbc->rdata.size = 0; - - while (recno > ++nrecs) - if ((ret = __ram_add(dbc, - &nrecs, &dbc->rdata, 0, BI_DELETED)) != 0) - return (ret); - return (0); -} - -/* - * __ram_source -- - * Load information about the backing file. - */ -static int -__ram_source(dbp, rp, fname) - DB *dbp; - RECNO *rp; - const char *fname; -{ - size_t size; - u_int32_t bytes, mbytes, oflags; - int ret; - - /* - * !!! - * The caller has full responsibility for cleaning up on error -- - * (it has to anyway, in case it fails after this routine succeeds). - */ - if ((ret = __db_appname(dbp->dbenv, - DB_APP_DATA, NULL, fname, 0, NULL, &rp->re_source)) != 0) - return (ret); - - oflags = F_ISSET(dbp, DB_AM_RDONLY) ? DB_RDONLY : 0; - if ((ret = - __db_open(rp->re_source, oflags, oflags, 0, &rp->re_fd)) != 0) { - __db_err(dbp->dbenv, "%s: %s", rp->re_source, strerror(ret)); - return (ret); - } - - /* - * XXX - * We'd like to test to see if the file is too big to mmap. Since we - * don't know what size or type off_t's or size_t's are, or the largest - * unsigned integral type is, or what random insanity the local C - * compiler will perpetrate, doing the comparison in a portable way is - * flatly impossible. Hope that mmap fails if the file is too large. - */ - if ((ret = __os_ioinfo(rp->re_source, - rp->re_fd, &mbytes, &bytes, NULL)) != 0) { - __db_err(dbp->dbenv, "%s: %s", rp->re_source, strerror(ret)); - return (ret); - } - if (mbytes == 0 && bytes == 0) { - F_SET(rp, RECNO_EOF); - return (0); - } - - size = mbytes * MEGABYTE + bytes; - if ((ret = __db_mapfile(rp->re_source, - rp->re_fd, (size_t)size, 1, &rp->re_smap)) != 0) - return (ret); - rp->re_cmap = rp->re_smap; - rp->re_emap = (u_int8_t *)rp->re_smap + (rp->re_msize = size); - rp->re_irec = F_ISSET(dbp, DB_RE_FIXEDLEN) ? __ram_fmap : __ram_vmap; - return (0); -} - -/* - * __ram_writeback -- - * Rewrite the backing file. - */ -static int -__ram_writeback(dbc) - DBC *dbc; -{ - DB *dbp; - DBT key, data; - RECNO *rp; - db_recno_t keyno; - ssize_t nw; - int fd, ret, t_ret; - u_int8_t delim, *pad; - - dbp = dbc->dbp; - rp = ((BTREE *)dbp->internal)->recno; - - /* If the file wasn't modified, we're done. */ - if (!F_ISSET(rp, RECNO_MODIFIED)) - return (0); - - /* If there's no backing source file, we're done. */ - if (rp->re_source == NULL) { - F_CLR(rp, RECNO_MODIFIED); - return (0); - } - - /* - * Read any remaining records into the tree. - * - * !!! - * This is why we can't support transactions when applications specify - * backing (re_source) files. At this point we have to read in the - * rest of the records from the file so that we can write all of the - * records back out again, which could modify a page for which we'd - * have to log changes and which we don't have locked. This could be - * partially fixed by taking a snapshot of the entire file during the - * db_open(), or, since db_open() isn't transaction protected, as part - * of the first DB operation. But, if a checkpoint occurs then, the - * part of the log holding the copy of the file could be discarded, and - * that would make it impossible to recover in the face of disaster. - * This could all probably be fixed, but it would require transaction - * protecting the backing source file, i.e. mpool would have to know - * about it, and we don't want to go there. - */ - if ((ret = - __ram_update(dbc, DB_MAX_RECORDS, 0)) != 0 && ret != DB_NOTFOUND) - return (ret); - - /* - * !!! - * Close any underlying mmap region. This is required for Windows NT - * (4.0, Service Pack 2) -- if the file is still mapped, the following - * open will fail. - */ - if (rp->re_smap != NULL) { - (void)__db_unmapfile(rp->re_smap, rp->re_msize); - rp->re_smap = NULL; - } - - /* Get rid of any backing file descriptor, just on GP's. */ - if (rp->re_fd != -1) { - (void)__os_close(rp->re_fd); - rp->re_fd = -1; - } - - /* Open the file, truncating it. */ - if ((ret = __db_open(rp->re_source, - DB_SEQUENTIAL | DB_TRUNCATE, - DB_SEQUENTIAL | DB_TRUNCATE, 0, &fd)) != 0) { - __db_err(dbp->dbenv, "%s: %s", rp->re_source, strerror(ret)); - return (ret); - } - - /* - * We step through the records, writing each one out. Use the record - * number and the dbp->get() function, instead of a cursor, so we find - * and write out "deleted" or non-existent records. - */ - memset(&key, 0, sizeof(key)); - memset(&data, 0, sizeof(data)); - key.size = sizeof(db_recno_t); - key.data = &keyno; - - /* - * We'll need the delimiter if we're doing variable-length records, - * and the pad character if we're doing fixed-length records. - */ - delim = rp->re_delim; - if (F_ISSET(dbp, DB_RE_FIXEDLEN)) { - if ((ret = __os_malloc(rp->re_len, NULL, &pad)) != 0) - goto err; - memset(pad, rp->re_pad, rp->re_len); - } else - COMPQUIET(pad, NULL); - for (keyno = 1;; ++keyno) { - switch (ret = dbp->get(dbp, NULL, &key, &data, 0)) { - case 0: - if ((ret = - __os_write(fd, data.data, data.size, &nw)) != 0) - goto err; - if (nw != (ssize_t)data.size) { - ret = EIO; - goto err; - } - break; - case DB_KEYEMPTY: - if (F_ISSET(dbp, DB_RE_FIXEDLEN)) { - if ((ret = - __os_write(fd, pad, rp->re_len, &nw)) != 0) - goto err; - if (nw != (ssize_t)rp->re_len) { - ret = EIO; - goto err; - } - } - break; - case DB_NOTFOUND: - ret = 0; - goto done; - } - if (!F_ISSET(dbp, DB_RE_FIXEDLEN)) { - if ((ret = __os_write(fd, &delim, 1, &nw)) != 0) - goto err; - if (nw != 1) { - ret = EIO; - goto err; - } - } - } - -err: -done: /* Close the file descriptor. */ - if ((t_ret = __os_close(fd)) != 0 || ret == 0) - ret = t_ret; - - if (ret == 0) - F_CLR(rp, RECNO_MODIFIED); - return (ret); -} - -/* - * __ram_fmap -- - * Get fixed length records from a file. - */ -static int -__ram_fmap(dbc, top) - DBC *dbc; - db_recno_t top; -{ - DB *dbp; - DBT data; - RECNO *rp; - db_recno_t recno; - u_int32_t len; - u_int8_t *sp, *ep, *p; - int ret; - - if ((ret = __bam_nrecs(dbc, &recno)) != 0) - return (ret); - - dbp = dbc->dbp; - rp = ((BTREE *)(dbp->internal))->recno; - - if (dbc->rdata.ulen < rp->re_len) { - if ((ret = __os_realloc(&dbc->rdata.data, rp->re_len)) != 0) { - dbc->rdata.ulen = 0; - dbc->rdata.data = NULL; - return (ret); - } - dbc->rdata.ulen = rp->re_len; - } - - memset(&data, 0, sizeof(data)); - data.data = dbc->rdata.data; - data.size = rp->re_len; - - sp = (u_int8_t *)rp->re_cmap; - ep = (u_int8_t *)rp->re_emap; - while (recno < top) { - if (sp >= ep) { - F_SET(rp, RECNO_EOF); - return (DB_NOTFOUND); - } - len = rp->re_len; - for (p = dbc->rdata.data; - sp < ep && len > 0; *p++ = *sp++, --len) - ; - - /* - * Another process may have read this record from the input - * file and stored it into the database already, in which - * case we don't need to repeat that operation. We detect - * this by checking if the last record we've read is greater - * or equal to the number of records in the database. - * - * XXX - * We should just do a seek, since the records are fixed - * length. - */ - if (rp->re_last >= recno) { - if (len != 0) - memset(p, rp->re_pad, len); - - ++recno; - if ((ret = __ram_add(dbc, &recno, &data, 0, 0)) != 0) - return (ret); - } - ++rp->re_last; - } - rp->re_cmap = sp; - return (0); -} - -/* - * __ram_vmap -- - * Get variable length records from a file. - */ -static int -__ram_vmap(dbc, top) - DBC *dbc; - db_recno_t top; -{ - DBT data; - RECNO *rp; - db_recno_t recno; - u_int8_t *sp, *ep; - int delim, ret; - - rp = ((BTREE *)(dbc->dbp->internal))->recno; - - if ((ret = __bam_nrecs(dbc, &recno)) != 0) - return (ret); - - memset(&data, 0, sizeof(data)); - - delim = rp->re_delim; - - sp = (u_int8_t *)rp->re_cmap; - ep = (u_int8_t *)rp->re_emap; - while (recno < top) { - if (sp >= ep) { - F_SET(rp, RECNO_EOF); - return (DB_NOTFOUND); - } - for (data.data = sp; sp < ep && *sp != delim; ++sp) - ; - - /* - * Another process may have read this record from the input - * file and stored it into the database already, in which - * case we don't need to repeat that operation. We detect - * this by checking if the last record we've read is greater - * or equal to the number of records in the database. - */ - if (rp->re_last >= recno) { - data.size = sp - (u_int8_t *)data.data; - ++recno; - if ((ret = __ram_add(dbc, &recno, &data, 0, 0)) != 0) - return (ret); - } - ++rp->re_last; - ++sp; - } - rp->re_cmap = sp; - return (0); -} - -/* - * __ram_add -- - * Add records into the tree. - */ -static int -__ram_add(dbc, recnop, data, flags, bi_flags) - DBC *dbc; - db_recno_t *recnop; - DBT *data; - u_int32_t flags, bi_flags; -{ - BKEYDATA *bk; - CURSOR *cp; - DB *dbp; - PAGE *h; - db_indx_t indx; - int exact, isdeleted, ret, stack; - - dbp = dbc->dbp; - cp = dbc->internal; - -retry: /* Find the slot for insertion. */ - if ((ret = __bam_rsearch(dbc, recnop, - S_INSERT | (flags == DB_APPEND ? S_APPEND : 0), 1, &exact)) != 0) - return (ret); - h = cp->csp->page; - indx = cp->csp->indx; - stack = 1; - - /* - * If re-numbering records, the on-page deleted flag means this record - * was implicitly created. If not re-numbering records, the on-page - * deleted flag means this record was implicitly created, or, it was - * deleted at some time. - * - * If DB_NOOVERWRITE is set and the item already exists in the tree, - * return an error unless the item was either marked for deletion or - * only implicitly created. - */ - isdeleted = 0; - if (exact) { - bk = GET_BKEYDATA(h, indx); - if (B_DISSET(bk->type)) - isdeleted = 1; - else - if (flags == DB_NOOVERWRITE) { - ret = DB_KEYEXIST; - goto err; - } - } - - /* - * Select the arguments for __bam_iitem() and do the insert. If the - * key is an exact match, or we're replacing the data item with a - * new data item, replace the current item. If the key isn't an exact - * match, we're inserting a new key/data pair, before the search - * location. - */ - switch (ret = __bam_iitem(dbc, - &h, &indx, NULL, data, exact ? DB_CURRENT : DB_BEFORE, bi_flags)) { - case 0: - /* - * Don't adjust anything. - * - * If we inserted a record, no cursors need adjusting because - * the only new record it's possible to insert is at the very - * end of the tree. The necessary adjustments to the internal - * page counts were made by __bam_iitem(). - * - * If we overwrote a record, no cursors need adjusting because - * future DBcursor->get calls will simply return the underlying - * record (there's no adjustment made for the DB_CURRENT flag - * when a cursor get operation immediately follows a cursor - * delete operation, and the normal adjustment for the DB_NEXT - * flag is still correct). - */ - break; - case DB_NEEDSPLIT: - /* Discard the stack of pages and split the page. */ - (void)__bam_stkrel(dbc, 0); - stack = 0; - - if ((ret = __bam_split(dbc, recnop)) != 0) - goto err; - - goto retry; - /* NOTREACHED */ - default: - goto err; - } - - -err: if (stack) - __bam_stkrel(dbc, 0); - - return (ret); -} |