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SergejJurecko/delerror.c

Last active Aug 29, 2015
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#include "lmdb.h"
#include <string.h>
#include <stdio.h>
#include <ctype.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdint.h>
# define DBG(X, ...) fprintf(stderr,X "\r\n",##__VA_ARGS__) ;
#define u8 unsigned char
#define u64 uint64_t
#define i64 int64_t
#define u32 unsigned int
typedef struct lmdb
{
MDB_env *menv;
MDB_txn *txn;
MDB_dbi pagesdb;
MDB_cursor *cursorPages;
}lmdb;
static int pagesdb_cmp(const MDB_val *a, const MDB_val *b)
{
u64 aActor;
u64 bActor;
u32 aPgno;
u32 bPgno;
int diff;
memcpy(&aActor,a->mv_data,sizeof(u64));
memcpy(&bActor,b->mv_data,sizeof(u64));
diff = aActor - bActor;
if (diff == 0)
{
memcpy(&aPgno,(u8*)a->mv_data + sizeof(u64),sizeof(u32));
memcpy(&bPgno,(u8*)b->mv_data + sizeof(u64),sizeof(u32));
return aPgno - bPgno;
}
return diff;
}
static int pagesdb_val_cmp(const MDB_val *a, const MDB_val *b)
{
u64 aEvterm,aEvnum;
u64 bEvterm,bEvnum;
u8 aCounter, bCounter;
int diff;
memcpy(&aEvterm, a->mv_data, sizeof(u64));
memcpy(&bEvterm, b->mv_data, sizeof(u64));
diff = aEvterm - bEvterm;
if (diff == 0)
{
memcpy(&aEvnum, (u8*)a->mv_data+sizeof(u64), sizeof(u64));
memcpy(&bEvnum, (u8*)b->mv_data+sizeof(u64), sizeof(u64));
diff = aEvnum - bEvnum;
if (diff == 0)
{
aCounter = ((u8*)a->mv_data)[sizeof(u64)*2];
bCounter = ((u8*)b->mv_data)[sizeof(u64)*2];
return aCounter - bCounter;
}
return diff;
}
return diff;
}
static int open_env(lmdb *lm, const char *pth, int flags)
{
if (mdb_env_create(&lm->menv) != MDB_SUCCESS)
return -1;
if (mdb_env_set_maxdbs(lm->menv,5) != MDB_SUCCESS)
return -1;
if (mdb_env_open(lm->menv, pth, MDB_NOSUBDIR | flags, 0664) != MDB_SUCCESS)
return -1;
if (mdb_txn_begin(lm->menv, NULL, flags, &lm->txn) != MDB_SUCCESS)
return -1;
if (mdb_dbi_open(lm->txn, "pages", MDB_DUPSORT, &lm->pagesdb) != MDB_SUCCESS)
return -1;
if (mdb_set_compare(lm->txn, lm->pagesdb, pagesdb_cmp) != MDB_SUCCESS)
return -1;
if (mdb_set_dupsort(lm->txn, lm->pagesdb, pagesdb_val_cmp) != MDB_SUCCESS)
return -1;
if (mdb_cursor_open(lm->txn, lm->pagesdb, &lm->cursorPages) != MDB_SUCCESS)
return -1;
return 0;
}
int main()
{
lmdb rd;
u8 pagesKeyBuf[sizeof(u64)+sizeof(u32)];
MDB_val pgKey = {0,NULL}, pgVal = {0,NULL};
u64 evnum,evterm,aindex = 126;
u32 pgno = 65;
int mrc;
memcpy(pagesKeyBuf, &aindex,sizeof(u64));
memcpy(pagesKeyBuf + sizeof(u64), &pgno, sizeof(u32));
pgKey.mv_data = pagesKeyBuf;
pgKey.mv_size = sizeof(pagesKeyBuf);
if (open_env(&rd, "lmdb", 0) == -1)
{
DBG("Unable to open source environment");
return 0;
}
if (mdb_cursor_get(rd.cursorPages,&pgKey,&pgVal,MDB_SET) != MDB_SUCCESS)
{
return 0;
}
if (mdb_cursor_get(rd.cursorPages,&pgKey,&pgVal,MDB_FIRST_DUP) != MDB_SUCCESS)
return 0;
do{
MDB_val pgDelKey = {0,NULL}, pgDelVal = {0,NULL};
mdb_cursor_get(rd.cursorPages,&pgDelKey,&pgDelVal,MDB_GET_CURRENT);
memcpy(&evterm, pgDelVal.mv_data, sizeof(u64));
memcpy(&evnum, (u8*)pgDelVal.mv_data+sizeof(u64),sizeof(u64));
DBG("Evnum=%llu",evnum);
// if (evnum > 5538)
if (evnum == 5538)
{
mrc = mdb_cursor_del(rd.cursorPages,0);
if (mrc != MDB_SUCCESS)
{
DBG("Unable to delete page on cursor! err=%d, evnum=%llu",mrc,evnum);
return 1;
}
DBG("Deleted");
}
}while (mdb_cursor_get(rd.cursorPages,&pgKey,&pgVal,MDB_NEXT_DUP) == MDB_SUCCESS);
mdb_txn_commit(rd.txn);
return 0;
}
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