/* $NetBSD: bt_put.c,v 1.14 2003/12/30 21:20:16 martin Exp $ */ /*- * Copyright (c) 1990, 1993, 1994 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Mike Olson. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #if defined(LIBC_SCCS) && !defined(lint) #if 0 static char sccsid[] = "@(#)bt_put.c 8.8 (Berkeley) 7/26/94"; #else __RCSID("$NetBSD: bt_put.c,v 1.14 2003/12/30 21:20:16 martin Exp $"); #endif #endif /* LIBC_SCCS and not lint */ #include "namespace.h" #include #include #include #include #include #include #include "btree.h" static EPG *bt_fast __P((BTREE *, const DBT *, const DBT *, int *)); /* * __BT_PUT -- Add a btree item to the tree. * * Parameters: * dbp: pointer to access method * key: key * data: data * flag: R_NOOVERWRITE * * Returns: * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key is already in the * tree and R_NOOVERWRITE specified. */ int __bt_put(dbp, key, data, flags) const DB *dbp; DBT *key; const DBT *data; u_int flags; { BTREE *t; DBT tkey, tdata; EPG *e = NULL; /* pacify gcc */ PAGE *h; indx_t idx, nxtindex; pgno_t pg; u_int32_t nbytes, temp; int dflags, exact, status; char *dest, db[NOVFLSIZE], kb[NOVFLSIZE]; t = dbp->internal; /* Toss any page pinned across calls. */ if (t->bt_pinned != NULL) { mpool_put(t->bt_mp, t->bt_pinned, 0); t->bt_pinned = NULL; } /* Check for change to a read-only tree. */ if (F_ISSET(t, B_RDONLY)) { errno = EPERM; return (RET_ERROR); } switch (flags) { case 0: case R_NOOVERWRITE: break; case R_CURSOR: /* * If flags is R_CURSOR, put the cursor. Must already * have started a scan and not have already deleted it. */ if (F_ISSET(&t->bt_cursor, CURS_INIT) && !F_ISSET(&t->bt_cursor, CURS_ACQUIRE | CURS_AFTER | CURS_BEFORE)) break; /* FALLTHROUGH */ default: errno = EINVAL; return (RET_ERROR); } /* * If the key/data pair won't fit on a page, store it on overflow * pages. Only put the key on the overflow page if the pair are * still too big after moving the data to an overflow page. * * XXX * If the insert fails later on, the overflow pages aren't recovered. */ dflags = 0; if (key->size + data->size > t->bt_ovflsize) { if (key->size > t->bt_ovflsize) { storekey: if (__ovfl_put(t, key, &pg) == RET_ERROR) return (RET_ERROR); tkey.data = kb; tkey.size = NOVFLSIZE; memmove(kb, &pg, sizeof(pgno_t)); memmove(kb + sizeof(pgno_t), &key->size, sizeof(u_int32_t)); dflags |= P_BIGKEY; key = &tkey; } if (key->size + data->size > t->bt_ovflsize) { if (__ovfl_put(t, data, &pg) == RET_ERROR) return (RET_ERROR); tdata.data = db; tdata.size = NOVFLSIZE; memmove(db, &pg, sizeof(pgno_t)); temp = data->size; memmove(db + sizeof(pgno_t), &temp, sizeof(u_int32_t)); dflags |= P_BIGDATA; data = &tdata; } if (key->size + data->size > t->bt_ovflsize) goto storekey; } /* Replace the cursor. */ if (flags == R_CURSOR) { if ((h = mpool_get(t->bt_mp, t->bt_cursor.pg.pgno, 0)) == NULL) return (RET_ERROR); idx = t->bt_cursor.pg.index; goto delete; } /* * Find the key to delete, or, the location at which to insert. * Bt_fast and __bt_search both pin the returned page. */ if (t->bt_order == NOT || (e = bt_fast(t, key, data, &exact)) == NULL) if ((e = __bt_search(t, key, &exact)) == NULL) return (RET_ERROR); h = e->page; idx = e->index; /* * Add the key/data pair to the tree. If an identical key is already * in the tree, and R_NOOVERWRITE is set, an error is returned. If * R_NOOVERWRITE is not set, the key is either added (if duplicates are * permitted) or an error is returned. */ switch (flags) { case R_NOOVERWRITE: if (!exact) break; mpool_put(t->bt_mp, h, 0); return (RET_SPECIAL); default: if (!exact || !F_ISSET(t, B_NODUPS)) break; /* * !!! * Note, the delete may empty the page, so we need to put a * new entry into the page immediately. */ delete: if (__bt_dleaf(t, key, h, (u_int)idx) == RET_ERROR) { mpool_put(t->bt_mp, h, 0); return (RET_ERROR); } break; } /* * If not enough room, or the user has put a ceiling on the number of * keys permitted in the page, split the page. The split code will * insert the key and data and unpin the current page. If inserting * into the offset array, shift the pointers up. */ nbytes = NBLEAFDBT(key->size, data->size); if (h->upper - h->lower < nbytes + sizeof(indx_t)) { if ((status = __bt_split(t, h, key, data, dflags, nbytes, (u_int)idx)) != RET_SUCCESS) return (status); goto success; } if (idx < (nxtindex = NEXTINDEX(h))) memmove(h->linp + idx + 1, h->linp + idx, (nxtindex - idx) * sizeof(indx_t)); h->lower += sizeof(indx_t); h->linp[idx] = h->upper -= nbytes; dest = (char *)(void *)h + h->upper; WR_BLEAF(dest, key, data, dflags); /* If the cursor is on this page, adjust it as necessary. */ if (F_ISSET(&t->bt_cursor, CURS_INIT) && !F_ISSET(&t->bt_cursor, CURS_ACQUIRE) && t->bt_cursor.pg.pgno == h->pgno && t->bt_cursor.pg.index >= idx) ++t->bt_cursor.pg.index; if (t->bt_order == NOT) { if (h->nextpg == P_INVALID) { if (idx == NEXTINDEX(h) - 1) { t->bt_order = FORWARD; t->bt_last.index = idx; t->bt_last.pgno = h->pgno; } } else if (h->prevpg == P_INVALID) { if (idx == 0) { t->bt_order = BACK; t->bt_last.index = 0; t->bt_last.pgno = h->pgno; } } } mpool_put(t->bt_mp, h, MPOOL_DIRTY); success: if (flags == R_SETCURSOR) __bt_setcur(t, e->page->pgno, (u_int)e->index); F_SET(t, B_MODIFIED); return (RET_SUCCESS); } #ifdef STATISTICS u_long bt_cache_hit, bt_cache_miss; #endif /* * BT_FAST -- Do a quick check for sorted data. * * Parameters: * t: tree * key: key to insert * * Returns: * EPG for new record or NULL if not found. */ static EPG * bt_fast(t, key, data, exactp) BTREE *t; const DBT *key, *data; int *exactp; { PAGE *h; u_int32_t nbytes; int cmp; if ((h = mpool_get(t->bt_mp, t->bt_last.pgno, 0)) == NULL) { t->bt_order = NOT; return (NULL); } t->bt_cur.page = h; t->bt_cur.index = t->bt_last.index; /* * If won't fit in this page or have too many keys in this page, * have to search to get split stack. */ nbytes = NBLEAFDBT(key->size, data->size); if (h->upper - h->lower < nbytes + sizeof(indx_t)) goto miss; if (t->bt_order == FORWARD) { if (t->bt_cur.page->nextpg != P_INVALID) goto miss; if (t->bt_cur.index != NEXTINDEX(h) - 1) goto miss; if ((cmp = __bt_cmp(t, key, &t->bt_cur)) < 0) goto miss; t->bt_last.index = cmp ? ++t->bt_cur.index : t->bt_cur.index; } else { if (t->bt_cur.page->prevpg != P_INVALID) goto miss; if (t->bt_cur.index != 0) goto miss; if ((cmp = __bt_cmp(t, key, &t->bt_cur)) > 0) goto miss; t->bt_last.index = 0; } *exactp = cmp == 0; #ifdef STATISTICS ++bt_cache_hit; #endif return (&t->bt_cur); miss: #ifdef STATISTICS ++bt_cache_miss; #endif t->bt_order = NOT; mpool_put(t->bt_mp, h, 0); return (NULL); }