bytes: Added support for decimal values (e.g. 1.2k)

Added use of `f128` internally (default feature gated.)

Fortune for units's current commit: Small blessing − 小吉

Cargo.lock

@@ -1,5 +1,7 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+version = 4
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -8,40 +10,31 @@ checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 
 [[package]]
 name = "rustc_version"
-version = "0.2.3"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
+checksum = "cfcb3a22ef46e85b45de6ee7e79d063319ebb6594faafcf1c225ea92ab6e9b92"
 dependencies = [
  "semver",
 ]
 
 [[package]]
 name = "semver"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
-dependencies = [
- "semver-parser",
-]
-
-[[package]]
-name = "semver-parser"
-version = "0.7.0"
+version = "1.0.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
+checksum = "56e6fa9c48d24d85fb3de5ad847117517440f6beceb7798af16b4a87d616b8d0"
 
 [[package]]
 name = "smallmap"
-version = "1.3.0"
+version = "1.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1d61d73d5986b7f728a76234ca60f7826faa44dd9043d2954ca6583bfc7b875d"
+checksum = "d6d0205d551de9bbfea07e51ace307c7f1ca224958a3df56fef6c2cfd244c199"
 dependencies = [
  "rustc_version",
 ]
 
 [[package]]
 name = "units"
-version = "0.1.0"
+version = "0.2.0"
 dependencies = [
  "lazy_static",
  "smallmap",

Cargo.toml

@@ -1,11 +1,25 @@
 [package]
 name = "units"
-version = "0.1.0"
+version = "0.2.0"
 authors = ["Avril <flanchan@cumallover.me>"]
-edition = "2018"
+edition = "2024"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[profile.release]
+opt-level = 3
+lto = true
+codegen-units = 1
+# TODO: Do we want to strip symbols if we plan to support loading plugins that can register units?
+strip = true
+
+
+[features]
+default=["f128-math"]
+
+# Use 128-bit floating-point math internally where possible.
+f128-math = []
+
 [dependencies]
 lazy_static = "1.4.0"
 smallmap = "1.3.0"

src/conv/bytes.rs

@@ -4,10 +4,15 @@ use smallmap::Map;
 #[derive(Debug)]
 pub struct Bytes;
 
-const KB: u64 = 1024;
+type BytesUnit = u128;
+type IntermediateUnit = f64;
+
+const KB: BytesUnit = 1024;
 
 lazy_static! {
-    static ref SUFFIX: Map<char, u64> = smallmap::smallmap! {
+    static ref SUFFIX: Map<char, BytesUnit> = smallmap::smallmap! {
+	{'b' => 1},
+	
 	{'k' => KB},
 	{'m' => KB * KB},
 	{'g' => KB * KB * KB},
@@ -15,27 +20,46 @@ lazy_static! {
     };
 }
 
+    #[cfg(feature="f128-math")]
+fn multiply(o: IntermediateUnit, u: BytesUnit) -> BytesUnit
+{
+    (o as f128 * (u as f128)).ceil() as BytesUnit
+}
+
+    #[cfg(not(feature="f128-math"))]
+fn multiply(o: IntermediateUnit, u: BytesUnit) -> BytesUnit
+{
+    (o * (u as f64)).ceil() as BytesUnit
+}
+
 impl Conversion for Bytes
 {
     const UNIT: &'static str = "bytes";
 
-    type Output = u64;
+    type Output = BytesUnit;
+    type Unit = BytesUnit;
 
     fn convert(&self, input: &str) -> Result<(Self::Output, Option<Self::Unit>), Self::Error>
     {
-	#[macro_export] macro_rules! parse {
-	    ($non:expr) => (($non).parse::<u64>().map_err(|e| ConversionError(format!("Failed to parse u64: {}", e)))?)
+	//TODO: Apparently, we cannot parse `f128` from string? See if there's another better way of doing this, or if there are fractional types at all...
+	macro_rules! parse {
+	    ($non:ident: $type:ty) => (($non).parse::<$type>().map_err(|e| ConversionError::new_for(self, format!("Failed to parse {}: {}", std::any::type_name::<$type>(), e)))?);
+	    ($non:ident) => (parse!($non: Self::Output));
 	}
 
 	let (o, u) = match input.char_indices().last().map(|(idx, chr)| (chr.to_lowercase().next().unwrap(), &input[..idx])) {
-	    Some((chr, _)) if chr.is_numeric() => (parse!(input), 1),
+	    Some((chr, _)) if chr.is_numeric() => return Ok((parse!(input: Self::Output), Some(1))),
 	    
-	    Some((ref chr, non)) if SUFFIX.contains_key(chr) => (parse!(non), *SUFFIX.get(chr).unwrap()),
+	    Some((ref chr, non)) if SUFFIX.contains_key(chr) => (parse!(non: IntermediateUnit), *SUFFIX.get(chr).unwrap()),
 	    
-	    Some((chr, _)) => return Err(ConversionError(format!("Unknown suffix {}", chr))),
-	    None => (0, 1),
+	    Some((chr, _)) => return Err(ConversionError::new_for(self, format!("Unknown suffix {}", chr))),
+	    None => (0 as IntermediateUnit, 1),
 	};
 
-	Ok((o * u, Some(u)))
+	if o.is_sign_negative() {
+	    return Err(ConversionError::new_for(self, "Negative byte offsets not supported"));
+	}
+	
+	Ok((multiply(o, u), Some(u)))
     }
 }

src/conv/mod.rs

@@ -1,5 +1,6 @@
 use std::error;
 use std::fmt;
+use std::borrow::Cow;
 use std::convert::Infallible;
 
 pub mod bytes;
@@ -16,14 +17,38 @@ pub trait Conversion
 }
 
 #[derive(Debug)]
-pub struct ConversionError(String);
+pub struct ConversionError
+{
+    message: Box<str>,
+    unit: Cow<'static, str>,
+}
+
+impl ConversionError
+{
+    #[inline] 
+    pub fn new_for<C: ?Sized + Conversion>(_conv: &C, message: impl Into<Box<str>>) -> Self
+    {
+	Self {
+	    message: message.into(),
+	    unit: Cow::Borrowed(C::UNIT),
+	}
+    }
+    #[inline] 
+    pub fn new(unit: impl ToString, message: impl Into<Box<str>>) -> Self
+    {
+	Self {
+	    message: message.into(),
+	    unit: Cow::Owned(unit.to_string()),
+	}
+    }
+}
 
 impl error::Error for ConversionError{}
 impl fmt::Display for ConversionError
 {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
     {
-	write!(f, "conversion failed: {}", self.0)
+	write!(f, "conversion of {} failed: {}", self.unit, self.message)
     }
 }
 
@@ -51,7 +76,7 @@ pub fn dispatch_out(unit: impl AsRef<str>, value: impl AsRef<str>) -> Result<(),
 {
     match unit.as_ref() {
 	bytes::Bytes::UNIT => print_output(bytes::Bytes.convert(value.as_ref())?),
-	name => return Err(ConversionError(format!("Unknown unit {}", name))),
+	name => return Err(ConversionError::new(name, "Unknown unit")),
     }
 
     Ok(())

src/main.rs

@@ -1,8 +1,9 @@
 #![feature(associated_type_defaults)]
+#![cfg_attr(feature="f128-math", feature(f128))] 
 
 #[macro_use] extern crate lazy_static;
 
-#[macro_export] macro_rules! unwrap {
+macro_rules! unwrap {
     ($err:expr) => {
 	match $err {
 	    Ok(v) => v,