Int formatting working

+ Using num-bigint to support arbitrarily sized ints
+ Added formatting tests
pull/1/head
Joey Hines 2021-10-09 08:42:17 -06:00
parent b85ba31f91
commit 9e5b0aafbd
No known key found for this signature in database
GPG Key ID: 80F567B5C968F91B
4 changed files with 127 additions and 13 deletions

37
Cargo.lock generated
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@ -22,6 +22,12 @@ dependencies = [
"winapi",
]
[[package]]
name = "autocfg"
version = "1.0.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
[[package]]
name = "bitflags"
version = "1.3.2"
@ -54,6 +60,7 @@ name = "formaty"
version = "0.1.0"
dependencies = [
"byteorder",
"num-bigint",
"serde",
"structopt",
"toml",
@ -89,6 +96,36 @@ version = "0.2.101"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "3cb00336871be5ed2c8ed44b60ae9959dc5b9f08539422ed43f09e34ecaeba21"
[[package]]
name = "num-bigint"
version = "0.4.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "74e768dff5fb39a41b3bcd30bb25cf989706c90d028d1ad71971987aa309d535"
dependencies = [
"autocfg",
"num-integer",
"num-traits",
]
[[package]]
name = "num-integer"
version = "0.1.44"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "d2cc698a63b549a70bc047073d2949cce27cd1c7b0a4a862d08a8031bc2801db"
dependencies = [
"autocfg",
"num-traits",
]
[[package]]
name = "num-traits"
version = "0.2.14"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "9a64b1ec5cda2586e284722486d802acf1f7dbdc623e2bfc57e65ca1cd099290"
dependencies = [
"autocfg",
]
[[package]]
name = "proc-macro-error"
version = "1.0.4"

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@ -9,4 +9,5 @@ edition = "2018"
structopt = "0.3.23"
serde = { version = "1.0", features = ["derive"] }
toml = "0.5.8"
byteorder = "1.4.3"
byteorder = "1.4.3"
num-bigint = "0.4"

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@ -3,7 +3,7 @@ pub enum ByteStreamError {
OutOfRange,
}
const fn bit_mask(mask: u8) -> u8 {
pub const fn bit_mask(mask: u8) -> u8 {
match mask {
0 => 0x00,
1 => 0x01,

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@ -1,6 +1,7 @@
use crate::byte_stream::ByteStream;
use crate::byte_stream::{ByteStream, bit_mask};
use serde::Deserialize;
use std::fmt::Write;
use num_bigint::{BigUint, BigInt};
#[derive(Debug, Deserialize, Clone)]
#[serde(tag = "type")]
@ -24,18 +25,38 @@ pub struct Field {
}
impl Field {
fn format_int(byte_stream: &ByteStream, bit_ndx: usize, bit_width: usize) -> (String, usize) {
let mut bytes = byte_stream.get_bytes(bit_ndx, bit_width).unwrap();
if let Some(last_byte) = bytes.last_mut() {
let last_bit = ((bit_width - 1) % 8) as u8;
let sign_bit = (*last_byte >> last_bit) & 0x1 == 1;
if sign_bit {
// Sign extend
*last_byte |= !bit_mask(last_bit + 1)
}
let big_int = BigInt::from_signed_bytes_be(&bytes);
(big_int.to_string(), bit_width)
}
else {
("".to_string(), bit_width)
}
}
fn format_uint(byte_stream: &ByteStream, bit_ndx: usize, bit_width: usize) -> (String, usize) {
let bytes = byte_stream.get_bytes(bit_ndx, bit_width).unwrap();
let big_int = BigUint::from_bytes_be(&bytes);
(big_int.to_string(), bit_width)
}
fn format_data(&self, byte_stream: &ByteStream, bit_ndx: usize) -> (String, usize) {
match self.field_type {
FieldType::UInt { bit_width } => {
let bytes = byte_stream.get_bytes(bit_ndx, bit_width).unwrap();
let mut string = String::with_capacity(bytes.len() * 2);
for byte in bytes.iter().rev() {
string.push_str(&format!("{:x}", byte))
}
(string, bit_width)
}
FieldType::UInt { bit_width } => Self::format_uint(byte_stream, bit_ndx, bit_width),
FieldType::Int { bit_width } => Self::format_int(byte_stream, bit_ndx, bit_width),
_ => ("".to_string(), 0),
}
}
@ -64,3 +85,58 @@ impl Format {
s
}
}
#[cfg(test)]
mod tests {
use crate::formatter::format::{FieldType, Field};
use crate::byte_stream::ByteStream;
#[test]
fn test_format_int_4_bits() {
let field = Field {field_type: FieldType::Int {bit_width: 4,}, name: "test".to_string()};
for i in 0i8..7i8 {
let mut byte_vec = Vec::new();
byte_vec.push(i as u8);
byte_vec.push((-i) as u8);
let byte_steam = ByteStream::from(byte_vec);
let (pos_output, _) = field.format_data(&byte_steam, 0);
let (neg_output, _) = field.format_data(&byte_steam, 8);
assert_eq!(pos_output, i.to_string());
assert_eq!(neg_output, (-i).to_string());
}
}
#[test]
fn test_format_int_5_bits() {
let field = Field {field_type: FieldType::Int {bit_width: 5,}, name: "test".to_string()};
let byte_steam = ByteStream::from(vec![0x1B]);
let (output, _) = field.format_data(&byte_steam, 0);
assert_eq!(output, "-5")
}
#[test]
fn test_format_int_16_bits() {
let field = Field {field_type: FieldType::Int {bit_width: 16,}, name: "test".to_string()};
let byte_steam = ByteStream::from(vec![0xA5, 0xFC]);
let (output, _) = field.format_data(&byte_steam, 0);
assert_eq!(output, "-23044")
}
#[test]
fn test_format_int_16_bits_not_aligned() {
let field = Field {field_type: FieldType::Int {bit_width: 16,}, name: "test".to_string()};
let byte_steam = ByteStream::from(vec![0x50, 0xCA, 0x0F]);
let (output, _) = field.format_data(&byte_steam, 4);
assert_eq!(output, "-23044")
}
}