use crate::block::Block;
use crate::cache::Cache;
use crate::cmp::{Cmp, DefaultCmp};
use crate::filter;
use crate::types::{share, Shared};
use std::default::Default;
use std::sync::Arc;
const KB: usize = 1 << 10;
const MB: usize = KB * KB;
const BLOCK_MAX_SIZE: usize = 4 * KB;
const BLOCK_CACHE_CAPACITY: usize = 8 * MB;
const WRITE_BUFFER_SIZE: usize = 4 * MB;
const DEFAULT_BITS_PER_KEY: u32 = 10; #[derive(Clone, Copy, PartialEq, Debug)]
pub enum CompressionType {
CompressionNone = 0,
CompressionSnappy = 1,
}
pub fn int_to_compressiontype(i: u32) -> Option<CompressionType> {
match i {
0 => Some(CompressionType::CompressionNone),
1 => Some(CompressionType::CompressionSnappy),
_ => None,
}
}
#[derive(Clone)]
pub struct Options {
pub cmp: Arc<Box<dyn Cmp>>,
pub write_buffer_size: usize,
pub block_cache: Shared<Cache<Block>>,
pub block_size: usize,
pub block_restart_interval: usize,
pub compression_type: CompressionType,
pub filter_policy: filter::BoxedFilterPolicy,
}
impl Options {
pub fn with_cache_capacity(mut self, capacity: usize) -> Options {
self.block_cache = share(Cache::new(capacity));
self
}
}
impl Default for Options {
fn default() -> Options {
Options {
cmp: Arc::new(Box::new(DefaultCmp)),
write_buffer_size: WRITE_BUFFER_SIZE,
block_cache: share(Cache::new(BLOCK_CACHE_CAPACITY / BLOCK_MAX_SIZE)),
block_size: BLOCK_MAX_SIZE,
block_restart_interval: 16,
compression_type: CompressionType::CompressionNone,
filter_policy: Arc::new(Box::new(filter::BloomPolicy::new(DEFAULT_BITS_PER_KEY))),
}
}
}