void db_save(const char* const name, uint8_t* data, uint32_t data_len)
{
if(false == db_init_done)
return;
if(0 != db_find(name))
db_delete(name);
uint32_t i, j;
uint8_t name_len = strlen(name);
i = db_index;
for(j = 0; j < name_len; j++) {
db_buf[i + j] = name[j];
}
db_buf[i + j] = '=';
i = i + j + 1;
for(j = 0; j < DATA_MSG_LEN; j++) {
db_buf[i + j] = (uint8_t)(data_len >> (j << 3));
}
i = i + j;
for(j = 0; j < data_len; j++) {
db_buf[i + j] = data[j];
}
db_buf[i + j] = '\n';
db_index = i + j + 1;
return;
}
void db_read(const char* const name, uint8_t* data)
{
if(false == db_init_done)
return;
uint32_t i, j, data_len;
i = db_find(name);
if(i == 0) {
data[0] = 0;
return;
}
data_len = get_len_by_pos(i);
for(j = 0; j < data_len; j++) {
data[j] = db_buf[i + j];
}
data[j] = 0;
}
void db_delete(const char* const name)
{
uint32_t i, pos, start, end, len;
uint32_t data_len = 0;
pos = db_find(name);
if(0 == pos)
return;
data_len = get_len_by_pos(pos);
for(start = pos; '\n' != db_buf[start]; start--);
end = pos + data_len;
len = end - start;
for(i = end; i < db_index; i++) {
db_buf[i - len] = db_buf[i];
}
for(i = i - len; i < db_index; i++) {
db_buf[i] = 0xff;
}
db_index -= len;
}
int db_delete(db_handle_t *db, uint64_t cardid)
{
int returnVal = 0;
if ( NULL == db) {
// This should not happen. So warn and return error
DBG_PRINT(DBG_WARN, ("Db handle is NULL"));
returnVal = HANDLE_NULL_ERROR;
goto DEL_ERROR;
} // if ( NULL == db )
#ifdef SQL_LITE
char sql[BUF_SIZE];
char *errMsg;
int counter = 0;
memset(sql, 0, BUF_SIZE);
#ifdef ALLOW_DUPLICATES
sprintf(sql, "SELECT * FROM %s WHERE id = %llu LIMIT 1", TABLE_NAME, cardid);
#else
sprintf(sql, "SELECT * FROM %s WHERE id = %llu", TABLE_NAME, cardid);
#endif
returnVal = sqlite3_exec(db->handle, sql, callback, (void *)&counter, &errMsg);
if ( returnVal ) {
DBG_PRINT(DBG_WARN, ("Error While Searching id = %lld. %s", cardid, errMsg));
sqlite3_free(errMsg);
returnVal = FIND_ERROR;
goto DEL_ERROR;
} // if ( returnVal )
if ( counter == 0 ) {
DBG_PRINT(DBG_WARN, ("Card id = %llu Not Found in Our Database", cardid));
returnVal = ELE_NOT_FOUND_ERROR;
goto DEL_ERROR;
} else {
memset(sql, 0, BUF_SIZE);
sprintf(sql, "DELETE FROM %s WHERE id = %llu LIMIT 1", TABLE_NAME, cardid);
returnVal = sqlite3_exec(db->handle, sql, NULL, 0, &errMsg);
if ( returnVal ) {
DBG_PRINT(DBG_WARN, ("Error While Deleting id = %llu. %s", cardid, errMsg));
sqlite3_free(errMsg);
returnVal = DELETE_ERROR;
goto DEL_ERROR;
} // if ( returnVal )
} // if ( counter == 0)
#else
returnVal = db_find(db, cardid);
if ( returnVal != 0 ) {
DBG_PRINT(DBG_WARN, ("Card id %llu Do Not Exists in Our Database"));
return ELE_NOT_FOUND_ERROR;
}
uint64_t id = 0ULL;
uint64_t prevId = 0ULL;
long left = -1L;
long right = -1L;
long curPos = -1L;
int totlen = sizeof(id) + sizeof(left) + sizeof(right);
fseek(db->handle, (long)-totlen, SEEK_CUR); // Move to the begining of record.
returnVal = fread(&id, sizeof(id), 1, db->handle);
returnVal = fread(&left, sizeof(left), 1, db->handle);
returnVal = fread(&right, sizeof(right), 1, db->handle);
if ( -1L == left && -1L == right) {
// Node is leaf.
curPos = ftell(db->handle) - ((long) (sizeof(uint64_t) + 2 * sizeof(long)));
if ( 0L == curPos ) {
// only one node in the tree. Truncate the file.
fclose(db->handle);
db->handle = fopen(db->fileName, "wb"); // reopen in write mode. It will truncate it.
returnVal = 0;
goto DEL_ERROR;
}
// Delete the link
fseek(db->handle, prevPos, SEEK_SET);
fread(&prevId, sizeof(prevId), 1, db->handle);
if ( prevId < id ) {
fseek(db->handle, prevPos + sizeof(left) + sizeof(prevId), SEEK_SET);
returnVal = fwrite(&right, sizeof(right), 1, db->handle);
} else {
returnVal = fwrite(&left, sizeof(left), 1, db->handle);
}
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
perror(NULL);
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
// Delete the node.
fseek(db->handle, curPos, SEEK_SET);
id = -1ULL;
returnVal = fwrite(&id, sizeof(id), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
return 0;
}
if ( -1L == left || -1L == right ) {
//Node with one child
if ( -1L == left ) {
curPos = ftell(db->handle) - ((long) (sizeof(uint64_t) + 2 * sizeof(long)));
fseek(db->handle, right, SEEK_SET);
fread(&id, sizeof(id), 1, db->handle);
fread(&left, sizeof(left), 1, db->handle);
fread(&right, sizeof(right), 1, db->handle);
fseek(db->handle, curPos, SEEK_SET);
returnVal = fwrite(&id, sizeof(id), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
returnVal = fwrite(&left, sizeof(left), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
returnVal = fwrite(&right, sizeof(right), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
return 0;
} // if ( -1L == left )
if ( -1L == right ) {
curPos = ftell(db->handle) - ((long) (sizeof(uint64_t) + 2 * sizeof(long)));
fseek(db->handle, left, SEEK_SET);
fread(&id, sizeof(id), 1, db->handle);
fread(&left, sizeof(left), 1, db->handle);
fread(&right, sizeof(right), 1, db->handle);
fseek(db->handle, curPos, SEEK_SET);
returnVal = fwrite(&id, sizeof(id), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
returnVal = fwrite(&left, sizeof(left), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
returnVal = fwrite(&right, sizeof(right), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
return 0;
} // if ( -1L == left )
} // if ( -1L == left || -1L == right )
// go to the left child and keep on going right untill you see an
// node with no right child.
curPos = ftell(db->handle) - ((long) (sizeof(uint64_t) + 2 * sizeof(long)));
long parentPos = curPos;
// go to left.
fseek(db->handle, left, SEEK_SET);
long temp = -1L;
while ( 1 ) {
// Keep on going right.
fread(&id, sizeof(id), 1, db->handle);
fread(&left, sizeof(left), 1, db->handle);
fread(&right, sizeof(right), 1, db->handle);
temp = ftell(db->handle) - ((long) sizeof(uint64_t) + 2 * sizeof(long));
if ( -1L == right )
break;
parentPos = temp;
fseek(db->handle, right, SEEK_SET);
}
long deletedPos = ftell(db->handle) - ((long) sizeof(uint64_t) + 2 * sizeof(long));
uint64_t replacementValue = id;
// delete the node.
if ( left == -1L && right == -1L ) {
fseek(db->handle, deletedPos, SEEK_SET);
fread(&id, sizeof(id), 1, db->handle);
fseek(db->handle, parentPos, SEEK_SET);
uint64_t parentId = -1ULL;
fread(&parentId, sizeof(parentId), 1, db->handle);
if ( parentId > id ) {
fwrite(&left, sizeof(left), 1, db->handle);
} else {
fseek(db->handle, sizeof(left), SEEK_CUR);
fwrite(&right, sizeof(right), 1, db->handle);
}
fseek(db->handle, deletedPos, SEEK_SET);
id = -1ULL;
returnVal = fwrite( &id, sizeof(id), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
fseek(db->handle, (long)(temp + sizeof(id) + sizeof(left)), SEEK_SET);
right = -1L;
returnVal = fwrite(&right, sizeof(right), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
// Replace the node.
fseek(db->handle, curPos, SEEK_SET);
returnVal = fwrite(&replacementValue, sizeof(replacementValue), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
return 0;
} else {
fseek(db->handle, curPos, SEEK_SET);
returnVal = fwrite(&replacementValue, sizeof(replacementValue), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
fseek(db->handle, left, SEEK_SET);
fread(&id, sizeof(id), 1, db->handle);
fread(&left, sizeof(left), 1, db->handle);
fread(&right, sizeof(right), 1, db->handle);
fseek(db->handle, deletedPos, SEEK_SET);
returnVal = fwrite(&id, sizeof(id), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
returnVal = fwrite(&left, sizeof(left), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
returnVal = fwrite(&right, sizeof(right), 1, db->handle);
if ( 1 != returnVal )
{
DBG_PRINT_ERR(("Something bad Happened\n Database Corrupted. Sorry !!"));
returnVal = DB_CORRUPT_ERROR;
goto DEL_ERROR;
}
fflush(db->handle);
return 0;
}
#endif // SQL_LITE
DEL_ERROR:
return returnVal;
}
