1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146

// This file is part of Substrate.

// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0

// 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 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.

//! `sc-network` type definitions

use libp2p::core::upgrade;

use std::{
	borrow::Borrow,
	fmt,
	hash::{Hash, Hasher},
	ops::Deref,
	sync::Arc,
};

/// The protocol name transmitted on the wire.
#[derive(Debug, Clone)]
pub enum ProtocolName {
	/// The protocol name as a static string.
	Static(&'static str),
	/// The protocol name as a dynamically allocated string.
	OnHeap(Arc<str>),
}

impl From<&'static str> for ProtocolName {
	fn from(name: &'static str) -> Self {
		Self::Static(name)
	}
}

impl From<Arc<str>> for ProtocolName {
	fn from(name: Arc<str>) -> Self {
		Self::OnHeap(name)
	}
}

impl From<String> for ProtocolName {
	fn from(name: String) -> Self {
		Self::OnHeap(Arc::from(name))
	}
}

impl Deref for ProtocolName {
	type Target = str;

	fn deref(&self) -> &str {
		match self {
			Self::Static(name) => name,
			Self::OnHeap(name) => &name,
		}
	}
}

impl Borrow<str> for ProtocolName {
	fn borrow(&self) -> &str {
		self
	}
}

impl PartialEq for ProtocolName {
	fn eq(&self, other: &Self) -> bool {
		(self as &str) == (other as &str)
	}
}

impl Eq for ProtocolName {}

impl Hash for ProtocolName {
	fn hash<H: Hasher>(&self, state: &mut H) {
		(self as &str).hash(state)
	}
}

impl fmt::Display for ProtocolName {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		f.write_str(self)
	}
}

impl upgrade::ProtocolName for ProtocolName {
	fn protocol_name(&self) -> &[u8] {
		(self as &str).as_bytes()
	}
}

#[cfg(test)]
mod tests {
	use super::ProtocolName;
	use std::{
		borrow::Borrow,
		collections::hash_map::DefaultHasher,
		hash::{Hash, Hasher},
	};

	#[test]
	fn protocol_name_keys_are_equivalent_to_str_keys() {
		const PROTOCOL: &'static str = "/some/protocol/1";
		let static_protocol_name = ProtocolName::from(PROTOCOL);
		let on_heap_protocol_name = ProtocolName::from(String::from(PROTOCOL));

		assert_eq!(<ProtocolName as Borrow<str>>::borrow(&static_protocol_name), PROTOCOL);
		assert_eq!(<ProtocolName as Borrow<str>>::borrow(&on_heap_protocol_name), PROTOCOL);
		assert_eq!(static_protocol_name, on_heap_protocol_name);

		assert_eq!(hash(static_protocol_name), hash(PROTOCOL));
		assert_eq!(hash(on_heap_protocol_name), hash(PROTOCOL));
	}

	#[test]
	fn different_protocol_names_do_not_compare_equal() {
		const PROTOCOL1: &'static str = "/some/protocol/1";
		let static_protocol_name1 = ProtocolName::from(PROTOCOL1);
		let on_heap_protocol_name1 = ProtocolName::from(String::from(PROTOCOL1));

		const PROTOCOL2: &'static str = "/some/protocol/2";
		let static_protocol_name2 = ProtocolName::from(PROTOCOL2);
		let on_heap_protocol_name2 = ProtocolName::from(String::from(PROTOCOL2));

		assert_ne!(<ProtocolName as Borrow<str>>::borrow(&static_protocol_name1), PROTOCOL2);
		assert_ne!(<ProtocolName as Borrow<str>>::borrow(&on_heap_protocol_name1), PROTOCOL2);
		assert_ne!(static_protocol_name1, static_protocol_name2);
		assert_ne!(static_protocol_name1, on_heap_protocol_name2);
		assert_ne!(on_heap_protocol_name1, on_heap_protocol_name2);
	}

	fn hash<T: Hash>(x: T) -> u64 {
		let mut hasher = DefaultHasher::new();
		x.hash(&mut hasher);
		hasher.finish()
	}
}