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/*************************************************************************************************
* Implementation of Relic
* Copyright (C) 2000-2007 Mikio Hirabayashi
* This file is part of QDBM, Quick Database Manager.
* QDBM is free software; you can redistribute it and/or modify it under the terms of the GNU
* Lesser General Public License as published by the Free Software Foundation; either version
* 2.1 of the License or any later version. QDBM is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
* You should have received a copy of the GNU Lesser General Public License along with QDBM; if
* not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
* 02111-1307 USA.
*************************************************************************************************/
#define QDBM_INTERNAL 1
#include "relic.h"
#include "myconf.h"
#define RL_NAMEMAX 512 /* max size of a database name */
#define RL_DIRFSUF MYEXTSTR "dir" /* suffix of a directory file */
#define RL_DATAFSUF MYEXTSTR "pag" /* suffix of a page file */
#define RL_PATHBUFSIZ 1024 /* size of a path buffer */
#define RL_INITBNUM 1913 /* initial bucket number */
#define RL_ALIGNSIZ 16 /* size of alignment */
#define RL_MAXLOAD 1.25 /* max ratio of bucket loading */
#define RL_DIRMAGIC "[depot]\0\v" /* magic number of a directory file */
/* private function prototypes */
static void dbm_writedummy(int fd);
static int dbm_writestr(int fd, const char *str);
/*************************************************************************************************
* public objects
*************************************************************************************************/
/* Get a database handle. */
DBM *dbm_open(char *name, int flags, int mode){
DBM *db;
DEPOT *depot;
int dpomode;
char path[RL_PATHBUFSIZ];
int dfd, fd;
assert(name);
if(strlen(name) > RL_NAMEMAX) return NULL;
dpomode = DP_OREADER;
if((flags & O_WRONLY) || (flags & O_RDWR)){
dpomode = DP_OWRITER;
if(flags & O_CREAT) dpomode |= DP_OCREAT;
if(flags & O_TRUNC) dpomode |= DP_OTRUNC;
}
mode |= 00600;
sprintf(path, "%s%s", name, RL_DIRFSUF);
if((dfd = open(path, flags, mode)) == -1) return NULL;
dbm_writedummy(dfd);
sprintf(path, "%s%s", name, RL_DATAFSUF);
if((fd = open(path, flags, mode)) == -1 || close(fd) == -1){
close(dfd);
return NULL;
}
if(!(depot = dpopen(path, dpomode, RL_INITBNUM))){
close(dfd);
return NULL;
}
if(dpomode & DP_OWRITER){
if(!dpsetalign(depot, RL_ALIGNSIZ)){
close(dfd);
dpclose(depot);
return NULL;
}
}
if(!(db = malloc(sizeof(DBM)))){
close(dfd);
dpclose(depot);
return NULL;
}
db->depot = depot;
db->dfd = dfd;
db->dbm_fetch_vbuf = NULL;
db->dbm_nextkey_kbuf = NULL;
return db;
}
/* Close a database handle. */
void dbm_close(DBM *db){
assert(db);
free(db->dbm_fetch_vbuf);
free(db->dbm_nextkey_kbuf);
close(db->dfd);
dpclose(db->depot);
free(db);
}
/* Store a record. */
int dbm_store(DBM *db, datum key, datum content, int flags){
int dmode;
int bnum, rnum;
assert(db);
if(!key.dptr || key.dsize < 0 || !content.dptr || content.dsize < 0) return -1;
dmode = (flags == DBM_INSERT) ? DP_DKEEP : DP_DOVER;
if(!dpput(db->depot, key.dptr, key.dsize, content.dptr, content.dsize, dmode)){
if(dpecode == DP_EKEEP) return 1;
return -1;
}
bnum = dpbnum(db->depot);
rnum = dprnum(db->depot);
if(bnum > 0 && rnum > 0 && ((double)rnum / (double)bnum > RL_MAXLOAD)){
if(!dpoptimize(db->depot, -1)) return -1;
}
return 0;
}
/* Delete a record. */
int dbm_delete(DBM *db, datum key){
assert(db);
if(!key.dptr || key.dsize < 0) return -1;
if(!dpout(db->depot, key.dptr, key.dsize)) return -1;
return 0;
}
/* Retrieve a record. */
datum dbm_fetch(DBM *db, datum key){
datum content;
char *vbuf;
int vsiz;
assert(db);
if(!key.dptr || key.dsize < 0 ||
!(vbuf = dpget(db->depot, key.dptr, key.dsize, 0, -1, &vsiz))){
content.dptr = NULL;
content.dsize = 0;
return content;
}
free(db->dbm_fetch_vbuf);
db->dbm_fetch_vbuf = vbuf;
content.dptr = vbuf;
content.dsize = vsiz;
return content;
}
/* Get the first key of a database. */
datum dbm_firstkey(DBM *db){
assert(db);
dpiterinit(db->depot);
return dbm_nextkey(db);
}
/* Get the next key of a database. */
datum dbm_nextkey(DBM *db){
datum key;
char *kbuf;
int ksiz;
if(!(kbuf = dpiternext(db->depot, &ksiz))){
key.dptr = NULL;
key.dsize = 0;
return key;
}
free(db->dbm_nextkey_kbuf);
db->dbm_nextkey_kbuf = kbuf;
key.dptr = kbuf;
key.dsize = ksiz;
return key;
}
/* Check whether a database has a fatal error or not. */
int dbm_error(DBM *db){
assert(db);
return dpfatalerror(db->depot) ? TRUE : FALSE;
}
/* No effect. */
int dbm_clearerr(DBM *db){
assert(db);
return 0;
}
/* Check whether a handle is read-only or not. */
int dbm_rdonly(DBM *db){
assert(db);
return dpwritable(db->depot) ? FALSE : TRUE;
}
/* Get the file descriptor of a directory file. */
int dbm_dirfno(DBM *db){
assert(db);
return db->dfd;
}
/* Get the file descriptor of a data file. */
int dbm_pagfno(DBM *db){
assert(db);
return dpfdesc(db->depot);
}
/*************************************************************************************************
* private objects
*************************************************************************************************/
/* Write dummy data into a dummy file.
`fd' specifies a file descriptor. */
static void dbm_writedummy(int fd){
struct stat sbuf;
if(fstat(fd, &sbuf) == -1 || sbuf.st_size > 0) return;
write(fd, RL_DIRMAGIC, sizeof(RL_DIRMAGIC) - 1);
dbm_writestr(fd, "\n\n");
dbm_writestr(fd, "\x20\x20\xa2\xca\xa1\xb2\xa2\xca\x20\x20\x20\x20\x20\xa1\xbf\xa1");
dbm_writestr(fd, "\xb1\xa1\xb1\xa1\xb1\xa1\xb1\xa1\xb1\xa1\xb1\xa1\xb1\xa1\xb1\xa1");
dbm_writestr(fd, "\xb1\x0a\xa1\xca\x20\xa1\xad\xa2\xcf\xa1\xae\xa1\xcb\xa1\xe3\x20");
dbm_writestr(fd, "\x20\x4e\x44\x42\x4d\x20\x43\x6f\x6d\x70\x61\x74\x69\x62\x69\x6c");
dbm_writestr(fd, "\x69\x74\x79\x0a\xa1\xca\x20\x20\x20\x20\x20\x20\x20\xa1\xcb\x20");
dbm_writestr(fd, "\x20\xa1\xc0\xa1\xb2\xa1\xb2\xa1\xb2\xa1\xb2\xa1\xb2\xa1\xb2\xa1");
dbm_writestr(fd, "\xb2\xa1\xb2\xa1\xb2\x0a\x20\xa1\xc3\x20\x20\xa1\xc3\x20\xa1\xc3");
dbm_writestr(fd, "\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20");
dbm_writestr(fd, "\x20\x20\x20\x20\x20\x20\x20\x0a\xa1\xca\x5f\x5f\xa1\xb2\xa1\xcb");
dbm_writestr(fd, "\x5f\xa1\xcb\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20");
dbm_writestr(fd, "\x20\x20\x20\x20\x20\x20\x20\x20\x20\x0a");
}
/* Write a string into a file.
`fd' specifies a file descriptor.
`str' specifies a string. */
static int dbm_writestr(int fd, const char *str){
const char *lbuf;
int size, rv, wb;
assert(fd >= 0 && str);
lbuf = str;
size = strlen(str);
rv = 0;
do {
wb = write(fd, lbuf, size);
switch(wb){
case -1: if(errno != EINTR) return -1;
case 0: break;
default:
lbuf += wb;
size -= wb;
rv += wb;
break;
}
} while(size > 0);
return rv;
}
/* END OF FILE */
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