cfx_rpc/helpers/
poll_filter.rs

1// Copyright 2015-2020 Parity Technologies (UK) Ltd.
2// This file is part of OpenEthereum.
3
4// OpenEthereum is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8
9// OpenEthereum is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12// GNU General Public License for more details.
13
14// You should have received a copy of the GNU General Public License
15// along with OpenEthereum.  If not, see <http://www.gnu.org/licenses/>.
16
17//! Helper type with all filter state data.
18
19use cfx_types::H256;
20
21use parking_lot::Mutex;
22use primitives::filter::LogFilter;
23use std::{
24    collections::{BTreeSet, VecDeque},
25    sync::Arc,
26};
27
28pub type EpochNumber = u64;
29
30/// Thread-safe filter state.
31#[derive(Clone)]
32pub struct SyncPollFilter<T>(Arc<Mutex<PollFilter<T>>>);
33
34impl<T> SyncPollFilter<T> {
35    /// New `SyncPollFilter`
36    pub fn new(f: PollFilter<T>) -> Self {
37        SyncPollFilter(Arc::new(Mutex::new(f)))
38    }
39
40    /// Modify underlying filter
41    pub fn modify<F, R>(&self, f: F) -> R
42    where F: FnOnce(&mut PollFilter<T>) -> R {
43        f(&mut self.0.lock())
44    }
45}
46
47/// Filter state.
48#[derive(Clone)]
49pub enum PollFilter<T> {
50    /// Number of last block which client was notified about.
51    Block {
52        last_epoch_number: EpochNumber,
53        #[doc(hidden)]
54        recent_reported_epochs: VecDeque<(EpochNumber, Vec<H256>)>,
55    },
56    /// Hashes of all pending transactions the client knows about.
57    PendingTransaction(BTreeSet<H256>),
58    /// Number of From block number, last seen block hash, pending logs and log
59    /// filter itself.
60    Logs {
61        last_epoch_number: EpochNumber,
62        recent_reported_epochs: VecDeque<(EpochNumber, Vec<H256>)>,
63        previous_logs: VecDeque<Vec<T>>,
64        filter: LogFilter,
65        include_pending: bool,
66    },
67}
68
69pub const MAX_BLOCK_HISTORY_SIZE: usize = 200;
70
71/// Returns only last `n` logs
72pub fn limit_logs<T>(mut logs: Vec<T>, limit: Option<usize>) -> Vec<T> {
73    let len = logs.len();
74    match limit {
75        Some(limit) if len >= limit => logs.split_off(len - limit),
76        _ => logs,
77    }
78}
cfx_rpc/helpers/poll_filter.rs

cfx_rpc/helpers/
poll_filter.rs
