1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/security/nss/lib/dbm/include/page.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,94 @@
1.4 +/*-
1.5 + * Copyright (c) 1990, 1993, 1994
1.6 + * The Regents of the University of California. All rights reserved.
1.7 + *
1.8 + * This code is derived from software contributed to Berkeley by
1.9 + * Margo Seltzer.
1.10 + *
1.11 + * Redistribution and use in source and binary forms, with or without
1.12 + * modification, are permitted provided that the following conditions
1.13 + * are met:
1.14 + * 1. Redistributions of source code must retain the above copyright
1.15 + * notice, this list of conditions and the following disclaimer.
1.16 + * 2. Redistributions in binary form must reproduce the above copyright
1.17 + * notice, this list of conditions and the following disclaimer in the
1.18 + * documentation and/or other materials provided with the distribution.
1.19 + * 3. ***REMOVED*** - see
1.20 + * ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
1.21 + * 4. Neither the name of the University nor the names of its contributors
1.22 + * may be used to endorse or promote products derived from this software
1.23 + * without specific prior written permission.
1.24 + *
1.25 + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
1.26 + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.27 + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.28 + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
1.29 + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
1.30 + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
1.31 + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1.32 + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
1.33 + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
1.34 + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
1.35 + * SUCH DAMAGE.
1.36 + *
1.37 + * @(#)page.h 8.2 (Berkeley) 5/31/94
1.38 + */
1.39 +
1.40 +/*
1.41 + * Definitions for hashing page file format.
1.42 + */
1.43 +
1.44 +/*
1.45 + * routines dealing with a data page
1.46 + *
1.47 + * page format:
1.48 + * +------------------------------+
1.49 + * p | n | keyoff | datoff | keyoff |
1.50 + * +------------+--------+--------+
1.51 + * | datoff | free | ptr | --> |
1.52 + * +--------+---------------------+
1.53 + * | F R E E A R E A |
1.54 + * +--------------+---------------+
1.55 + * | <---- - - - | data |
1.56 + * +--------+-----+----+----------+
1.57 + * | key | data | key |
1.58 + * +--------+----------+----------+
1.59 + *
1.60 + * Pointer to the free space is always: p[p[0] + 2]
1.61 + * Amount of free space on the page is: p[p[0] + 1]
1.62 + */
1.63 +
1.64 +/*
1.65 + * How many bytes required for this pair?
1.66 + * 2 shorts in the table at the top of the page + room for the
1.67 + * key and room for the data
1.68 + *
1.69 + * We prohibit entering a pair on a page unless there is also room to append
1.70 + * an overflow page. The reason for this it that you can get in a situation
1.71 + * where a single key/data pair fits on a page, but you can't append an
1.72 + * overflow page and later you'd have to split the key/data and handle like
1.73 + * a big pair.
1.74 + * You might as well do this up front.
1.75 + */
1.76 +#ifndef PAGE_H
1.77 +#define PAGE_H
1.78 +
1.79 +#define PAIRSIZE(K,D) (2*sizeof(uint16) + (K)->size + (D)->size)
1.80 +#define BIGOVERHEAD (4*sizeof(uint16))
1.81 +#define KEYSIZE(K) (4*sizeof(uint16) + (K)->size);
1.82 +#define OVFLSIZE (2*sizeof(uint16))
1.83 +#define FREESPACE(P) ((P)[(P)[0]+1])
1.84 +#define OFFSET(P) ((P)[(P)[0]+2])
1.85 +#define PAIRFITS(P,K,D) \
1.86 + (((P)[2] >= REAL_KEY) && \
1.87 + (PAIRSIZE((K),(D)) + OVFLSIZE) <= FREESPACE((P)))
1.88 +#define PAGE_META(N) (((N)+3) * sizeof(uint16))
1.89 +
1.90 +typedef struct {
1.91 + BUFHEAD *newp;
1.92 + BUFHEAD *oldp;
1.93 + BUFHEAD *nextp;
1.94 + uint16 next_addr;
1.95 +} SPLIT_RETURN;
1.96 +#endif
1.97 +
