171 lines
5.5 KiB
C++
171 lines
5.5 KiB
C++
/* $Id: msgcat.h,v 1.1 1995/03/30 12:47:27 jkh Exp $ */
|
|
|
|
/* -*-c++-*- */
|
|
|
|
#ifndef __msgcath
|
|
|
|
|
|
/***********************************************************
|
|
Copyright 1990, by Alfalfa Software Incorporated, Cambridge, Massachusetts.
|
|
|
|
All Rights Reserved
|
|
|
|
Permission to use, copy, modify, and distribute this software and its
|
|
documentation for any purpose and without fee is hereby granted,
|
|
provided that the above copyright notice appear in all copies and that
|
|
both that copyright notice and this permission notice appear in
|
|
supporting documentation, and that Alfalfa's name not be used in
|
|
advertising or publicity pertaining to distribution of the software
|
|
without specific, written prior permission.
|
|
|
|
ALPHALPHA DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
|
|
ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
|
|
ALPHALPHA BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
|
|
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
|
|
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
|
|
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
|
|
SOFTWARE.
|
|
|
|
If you make any modifications, bugfixes or other changes to this software
|
|
we'd appreciate it if you could send a copy to us so we can keep things
|
|
up-to-date. Many thanks.
|
|
Kee Hinckley
|
|
Alfalfa Software, Inc.
|
|
267 Allston St., #3
|
|
Cambridge, MA 02139 USA
|
|
nazgul@alfalfa.com
|
|
|
|
******************************************************************/
|
|
|
|
|
|
#include <sys/types.h>
|
|
|
|
/*
|
|
* On disk data structures
|
|
*/
|
|
|
|
/* Edit History
|
|
|
|
02/25/91 2 nazgul Byte order flags, upped the version number
|
|
11/03/90 1 hamilton Alphalpha->Alfalfa & OmegaMail->Poste
|
|
08/13/90 1 schulert move from ua to omu
|
|
*/
|
|
|
|
/* For or'd constants */
|
|
#define MCMakeId(s,m) (unsigned long) ( ((unsigned short)s << (sizeof(short)*8)) \
|
|
| (unsigned short)m )
|
|
#define MCSetId(id) (unsigned int) ( id >> (sizeof(short) * 8) )
|
|
#define MCMsgId(id) (unsigned int) ( (id << (sizeof(short) * 8)) \
|
|
>> (sizeof(short) * 8) )
|
|
#undef S
|
|
#undef UI
|
|
#undef UL
|
|
|
|
#define MCMagicLen 8
|
|
#define MCMagic "*nazgul*"
|
|
#define MCLastMsg 0
|
|
#define MCLastSet 0
|
|
|
|
#define MCMajorVer 1
|
|
#define MCMinorVer 0
|
|
|
|
/*
|
|
* Critical note here. Sets and Messages *MUST* be stored in ascending
|
|
* order. There are stored that way (by specification) in the original
|
|
* data file, however in the process of merging in new stuff you might
|
|
* mix that up. Don't! The catget stuff does a binary search and will
|
|
* totally lose it if these aren't in order (not contiguous mind you, just
|
|
* in order. If this turns out to be a major problem this could be enhanced
|
|
* by adding a 'sorted' flag to the db, and sorting msgs and sets at load
|
|
* time if things aren't sorted, but I'd like not to have to do that.
|
|
*/
|
|
|
|
/*
|
|
* I have tried here to define data structures which can be used
|
|
* while the catalog is on disk, and at runtime.
|
|
* This is rather dangerous of course, but I think it can be done without
|
|
* overly increasing the memory usage, and it makes loading and storing
|
|
* somewhat simpler and less prone to accidents. I have also tried to
|
|
* define on disk data structures which can be updated in place, so that
|
|
* with a very large catalog (e.g. all system errors) you don't have to
|
|
* load everything in memory in order to add or update one set. With
|
|
* this in mind there are "invalid" flags which allow items to be
|
|
* invalidated and thus not loaded at runtime. Note however that although
|
|
* I pay attention to these when I load the DB, I do not currently use
|
|
* them in gencat (it just reads everything into memory), so there is
|
|
* no guarantee that this will all work.
|
|
*/
|
|
|
|
/* These should be publicly available */
|
|
|
|
#define MCLoadBySet 0 /* Load entire sets as they are used */
|
|
#define MCLoadAll 1 /* Load entire DB on catopen */
|
|
|
|
/*
|
|
* MCOffsetT - Union to handle both disk and runtime pointers
|
|
*/
|
|
typedef union {
|
|
off_t off;
|
|
char *str;
|
|
void *ptr;
|
|
struct _MCMsgT *msg;
|
|
struct _MCSetT *set;
|
|
} MCOffsetT;
|
|
|
|
/*
|
|
* MCMsgT - Message structure (disk and runtime)
|
|
*/
|
|
typedef struct _MCMsgT {
|
|
long msgId; /* Id of this message */
|
|
MCOffsetT msg; /* Relative offset on disk or pointer in memory */
|
|
long invalid; /* Valid on disk, loaded in memory */
|
|
} MCMsgT;
|
|
|
|
/*
|
|
* MCSetT - Set structure (disk and runtime)
|
|
*/
|
|
typedef struct _MCSetT {
|
|
long setId; /* Id of this set */
|
|
off_t nextSet; /* Offset of next set on disk */
|
|
union {
|
|
off_t firstMsg; /* Offset to first Msg (while on disk) */
|
|
MCMsgT *msgs; /* Pointer to array of msgs (in mem, loaded) */
|
|
} u;
|
|
MCOffsetT data; /* Offset to data, or pointer to data */
|
|
long dataLen; /* Length of data area on disk */
|
|
long numMsgs; /* Number of messages */
|
|
long invalid; /* Valid on disk, loaded in memory */
|
|
} MCSetT;
|
|
|
|
/*
|
|
* MCCatT - Runtime catalog pointer
|
|
*/
|
|
typedef struct {
|
|
long loadType; /* How to load the messages (see MSLoadType) */
|
|
int fd; /* File descriptor of catalog (if load-on-demand) */
|
|
long numSets; /* Number of sets */
|
|
MCSetT *sets; /* Pointer to the sets */
|
|
off_t firstSet; /* Offset of first set on disk */
|
|
} MCCatT;
|
|
|
|
/*
|
|
* MCHeaderT - Disk file header
|
|
*/
|
|
typedef struct {
|
|
char magic[MCMagicLen]; /* Magic cookie "*nazgul*" */
|
|
long majorVer; /* ++ on incompatible changes */
|
|
long minorVer; /* ++ on compatible changes */
|
|
long flags; /* Informational flags */
|
|
long numSets; /* Number of valid Sets */
|
|
off_t firstSet; /* Offset of first set on disk */
|
|
} MCHeaderT;
|
|
|
|
/* Some flags */
|
|
#define MC68KByteOrder 0x01
|
|
#define MCn86ByteOrder 0x02
|
|
|
|
|
|
|
|
|
|
#endif
|