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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <stdint.h>
#include <limits.h>
#include <string.h>
#include "utf8_aux.h"
#include "btsearch.h"
#if 0
#define DEBUGF printf
#else
#define DEBUGF(...)
#endif
#define ROCKBOX_LITTLE_ENDIAN
#define KEY_MAXLEN 200
static inline unsigned short swap16(unsigned short value)
/*
result[15..8] = value[ 7..0];
result[ 7..0] = value[15..8];
*/
{
return (value >> 8) | (value << 8);
}
static inline unsigned long swap32(unsigned long value)
/*
result[31..24] = value[ 7.. 0];
result[23..16] = value[15.. 8];
result[15.. 8] = value[23..16];
result[ 7.. 0] = value[31..24];
*/
{
unsigned long hi = swap16(value >> 16);
unsigned long lo = swap16(value & 0xffff);
return (lo << 16) | hi;
}
#ifdef ROCKBOX_LITTLE_ENDIAN
#define letoh16(x) (x)
#define letoh32(x) (x)
#else
#define letoh16(x) swap16(x)
#define letoh32(x) swap32(x)
#endif
#ifdef BTSEARCH_MAIN
int main(int argc,char * argv[])
{
if(argc<3)
printf("Usage: btsearch <file> <key>\n");
else
{
FILE *fd=fopen(argv[1],"r");
uint32_t res_lo;
uint32_t res_hi;
fseek(fd,0,SEEK_SET);
search_btree(fd, argv[2], strlen(argv[2]), 0, &res_lo, &res_hi, false);
printf("Result: %d,%d\n",res_lo,res_hi);
}
return 0;
}
#endif
void search_btree(void* file, const char* key, uint16_t rkeylen, uint32_t globoffs,
uint32_t* res_lo, uint32_t* res_hi, const bool casesense)
{
unsigned char nd_key[KEY_MAXLEN];
uint8_t node_flags;
uint16_t node_nr_active,i,keylen;
uint32_t chldptr;
uint64_t dtaptr_lo,dtaptr_hi;
fread(&node_flags,sizeof(uint8_t),1,file);
fread(&node_nr_active,sizeof(uint16_t),1,file);
node_nr_active=letoh16(node_nr_active);
if(node_nr_active<1) /* error */
goto err;
for(i=0; i<node_nr_active; i++)
{
fread(&dtaptr_lo,sizeof(uint32_t),1,file);
dtaptr_lo=letoh32(dtaptr_lo);
fread(&dtaptr_hi,sizeof(uint32_t),1,file);
dtaptr_hi=letoh32(dtaptr_hi);
fread(&chldptr,sizeof(uint32_t),1,file);
chldptr=letoh32(chldptr);
fread(&keylen,sizeof(uint16_t),1,file);
keylen=letoh32(keylen);
fread(&nd_key,sizeof(unsigned char),(keylen<KEY_MAXLEN) ? keylen : KEY_MAXLEN,file);
if(keylen-((keylen<KEY_MAXLEN) ? keylen : KEY_MAXLEN)>0)
fseek(file,keylen-((keylen<KEY_MAXLEN) ? keylen : KEY_MAXLEN),SEEK_CUR);
keylen=(keylen<KEY_MAXLEN) ? keylen : KEY_MAXLEN;
nd_key[keylen]=0;
DEBUGF("CMP: %s, %s\n", key, nd_key);
if(utf8strcnmp(((const unsigned char*)key),((const unsigned char*)nd_key),rkeylen,keylen,casesense)>0)
continue;
if(utf8strcnmp(((const unsigned char*)key),((const unsigned char*)nd_key),rkeylen,keylen,casesense)==0)
{
DEBUGF("Found! %s\n", nd_key);
*res_lo=dtaptr_lo;
*res_hi=dtaptr_hi;
return;
}
if(chldptr==0||node_flags==1)
goto err;
fseek(file,globoffs+chldptr,SEEK_SET);
search_btree(file,key,rkeylen,globoffs,res_lo,res_hi,casesense);
return;
}
if(node_flags!=1) /* node not leaf */
{
fread(&chldptr,sizeof(uint32_t),1,file);
chldptr=letoh32(chldptr);
if(chldptr==0) /* leaf */
goto err;
fseek(file,globoffs+chldptr,SEEK_SET);
search_btree(file,key,rkeylen,globoffs,res_lo,res_hi,casesense);
}
return;
err:
*res_lo=*res_hi=0;
}
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