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

// This file is part of Substrate.

// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// 	http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! Wrapper type for byte collections that outputs hex.

/// Simple wrapper to display hex representation of bytes.
pub struct HexDisplay<'a>(&'a [u8]);

impl<'a> HexDisplay<'a> {
	/// Create new instance that will display `d` as a hex string when displayed.
	pub fn from<R: AsBytesRef>(d: &'a R) -> Self {
		HexDisplay(d.as_bytes_ref())
	}
}

impl<'a> core::fmt::Display for HexDisplay<'a> {
	fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
		if self.0.len() < 1027 {
			for byte in self.0 {
				f.write_fmt(format_args!("{:02x}", byte))?;
			}
		} else {
			for byte in &self.0[0..512] {
				f.write_fmt(format_args!("{:02x}", byte))?;
			}
			f.write_str("...")?;
			for byte in &self.0[self.0.len() - 512..] {
				f.write_fmt(format_args!("{:02x}", byte))?;
			}
		}
		Ok(())
	}
}

impl<'a> core::fmt::Debug for HexDisplay<'a> {
	fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
		for byte in self.0 {
			f.write_fmt(format_args!("{:02x}", byte))?;
		}
		Ok(())
	}
}

/// Simple trait to transform various types to `&[u8]`
pub trait AsBytesRef {
	/// Transform `self` into `&[u8]`.
	fn as_bytes_ref(&self) -> &[u8];
}

impl AsBytesRef for &[u8] {
	fn as_bytes_ref(&self) -> &[u8] {
		self
	}
}

impl AsBytesRef for [u8] {
	fn as_bytes_ref(&self) -> &[u8] {
		self
	}
}

impl AsBytesRef for alloc::vec::Vec<u8> {
	fn as_bytes_ref(&self) -> &[u8] {
		self
	}
}

impl AsBytesRef for sp_storage::StorageKey {
	fn as_bytes_ref(&self) -> &[u8] {
		self.as_ref()
	}
}

macro_rules! impl_non_endians {
	( $( $t:ty ),* ) => { $(
		impl AsBytesRef for $t {
			fn as_bytes_ref(&self) -> &[u8] { &self[..] }
		}
	)* }
}

impl_non_endians!(
	[u8; 1], [u8; 2], [u8; 3], [u8; 4], [u8; 5], [u8; 6], [u8; 7], [u8; 8], [u8; 10], [u8; 12],
	[u8; 14], [u8; 16], [u8; 20], [u8; 24], [u8; 28], [u8; 32], [u8; 40], [u8; 48], [u8; 56],
	[u8; 64], [u8; 65], [u8; 80], [u8; 96], [u8; 112], [u8; 128], [u8; 144], [u8; 177]
);

/// Format into ASCII + # + hex, suitable for storage key preimages.
#[cfg(feature = "std")]
pub fn ascii_format(asciish: &[u8]) -> String {
	let mut r = String::new();
	let mut latch = false;
	for c in asciish {
		match (latch, *c) {
			(false, 32..=127) => r.push(*c as char),
			_ => {
				if !latch {
					r.push('#');
					latch = true;
				}
				r.push_str(&format!("{:02x}", *c));
			},
		}
	}
	r
}