From: DongHun Kwak Date: Sun, 9 Apr 2023 23:57:24 +0000 (+0900) Subject: Import uuid-macro-internal 1.3.1 X-Git-Tag: upstream/1.3.1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=refs%2Fheads%2Fupstream;p=platform%2Fupstream%2Frust-uuid-macro-internal.git Import uuid-macro-internal 1.3.1 --- d763efd4e6d294b2809de869cf52c0a8a3be26fd diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json new file mode 100644 index 0000000..0d5703d --- /dev/null +++ b/.cargo_vcs_info.json @@ -0,0 +1,6 @@ +{ + "git": { + "sha1": "87082b92398cf8b20ded44a6669b3d0dc51a0b44" + }, + "path_in_vcs": "macros" +} \ No newline at end of file diff --git a/COPYRIGHT b/COPYRIGHT new file mode 100644 index 0000000..488e533 --- /dev/null +++ b/COPYRIGHT @@ -0,0 +1,7 @@ +The Uuid Project is copyright 2021, The Uuid Developers. + +Licensed under the Apache License, Version 2.0 or the MIT License , at your option. All files in the project +carrying such notice may not be copied, modified, or distributed except +according to those terms. diff --git a/Cargo.toml b/Cargo.toml new file mode 100644 index 0000000..9399021 --- /dev/null +++ b/Cargo.toml @@ -0,0 +1,38 @@ +# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO +# +# When uploading crates to the registry Cargo will automatically +# "normalize" Cargo.toml files for maximal compatibility +# with all versions of Cargo and also rewrite `path` dependencies +# to registry (e.g., crates.io) dependencies. +# +# If you are reading this file be aware that the original Cargo.toml +# will likely look very different (and much more reasonable). +# See Cargo.toml.orig for the original contents. + +[package] +edition = "2018" +name = "uuid-macro-internal" +version = "1.3.1" +authors = ["QnnOkabayashi"] +description = "Private implementation details of the uuid! macro." +documentation = "https://docs.rs/uuid" +categories = [ + "data-structures", + "no-std", + "parser-implementations", + "wasm", +] +license = "Apache-2.0 OR MIT" + +[lib] +proc-macro = true + +[dependencies.proc-macro2] +version = "1.0.29" +features = ["span-locations"] + +[dependencies.quote] +version = "1.0.10" + +[dependencies.syn] +version = "2.0.5" diff --git a/Cargo.toml.orig b/Cargo.toml.orig new file mode 100644 index 0000000..1e32f13 --- /dev/null +++ b/Cargo.toml.orig @@ -0,0 +1,29 @@ +[package] +name = "uuid-macro-internal" +version = "1.3.1" +edition = "2018" +authors = [ + "QnnOkabayashi" +] +categories = [ + "data-structures", + "no-std", + "parser-implementations", + "wasm" +] +description = "Private implementation details of the uuid! macro." +documentation = "https://docs.rs/uuid" +license = "Apache-2.0 OR MIT" + +[lib] +proc-macro = true + +[dependencies.syn] +version = "2.0.5" + +[dependencies.quote] +version = "1.0.10" + +[dependencies.proc-macro2] +version = "1.0.29" +features = ["span-locations"] diff --git a/LICENSE-APACHE b/LICENSE-APACHE new file mode 100644 index 0000000..16fe87b --- /dev/null +++ b/LICENSE-APACHE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + +TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + +1. 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IN NO EVENT +SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR +IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +DEALINGS IN THE SOFTWARE. diff --git a/src/error.rs b/src/error.rs new file mode 100644 index 0000000..76288b9 --- /dev/null +++ b/src/error.rs @@ -0,0 +1,144 @@ +use std::fmt; + +/// A general error that can occur when working with UUIDs. +#[derive(Clone, Debug, Eq, Hash, PartialEq)] +pub struct Error(pub(crate) ErrorKind); + +#[derive(Clone, Debug, Eq, Hash, PartialEq)] +pub(crate) enum ErrorKind { + /// Invalid character in the [`Uuid`] string. + /// + /// [`Uuid`]: ../struct.Uuid.html + Char { character: char, index: usize }, + /// A simple [`Uuid`] didn't contain 32 characters. + /// + /// [`Uuid`]: ../struct.Uuid.html + SimpleLength { len: usize }, + /// A hyphenated [`Uuid`] didn't contain 5 groups + /// + /// [`Uuid`]: ../struct.Uuid.html + GroupCount { count: usize }, + /// A hyphenated [`Uuid`] had a group that wasn't the right length + /// + /// [`Uuid`]: ../struct.Uuid.html + GroupLength { + group: usize, + len: usize, + index: usize, + }, +} + +/// A string that is guaranteed to fail to parse to a [`Uuid`]. +/// +/// This type acts as a lightweight error indicator, suggesting +/// that the string cannot be parsed but offering no error +/// details. To get details, use `InvalidUuid::into_err`. +/// +/// [`Uuid`]: ../struct.Uuid.html +#[derive(Clone, Debug, Eq, Hash, PartialEq)] +pub struct InvalidUuid<'a>(pub(crate) &'a str); + +impl<'a> InvalidUuid<'a> { + /// Converts the lightweight error type into detailed diagnostics. + pub fn into_err(self) -> Error { + let (s, offset, simple) = match self.0.as_bytes() { + [b'{', s @ .., b'}'] => (s, 1, false), + [b'u', b'r', b'n', b':', b'u', b'u', b'i', b'd', b':', s @ ..] => { + (s, "urn:uuid:".len(), false) + } + s => (s, 0, true), + }; + + let mut hyphen_count = 0; + let mut group_bounds = [0; 4]; + + // SAFETY: the byte array came from a valid utf8 string, + // and is aligned along char boundries. + let string = unsafe { std::str::from_utf8_unchecked(s) }; + + for (index, character) in string.char_indices() { + let byte = character as u8; + if character as u32 - byte as u32 > 0 { + // Multibyte char + return Error(ErrorKind::Char { + character, + index: index + offset + 1, + }); + } else if byte == b'-' { + // While we search, also count group breaks + if hyphen_count < 4 { + group_bounds[hyphen_count] = index; + } + hyphen_count += 1; + } else if !matches!(byte, b'0'..=b'9' | b'a'..=b'f' | b'A'..=b'F') { + // Non-hex char + return Error(ErrorKind::Char { + character: byte as char, + index: index + offset + 1, + }); + } + } + + if hyphen_count == 0 && simple { + // This means that we tried and failed to parse a simple uuid. + // Since we verified that all the characters are valid, this means + // that it MUST have an invalid length. + Error(ErrorKind::SimpleLength { len: s.len() }) + } else if hyphen_count != 4 { + // We tried to parse a hyphenated variant, but there weren't + // 5 groups (4 hyphen splits). + Error(ErrorKind::GroupCount { + count: hyphen_count + 1, + }) + } else { + // There are 5 groups, one of them has an incorrect length + const BLOCK_STARTS: [usize; 5] = [0, 9, 14, 19, 24]; + for i in 0..4 { + if group_bounds[i] != BLOCK_STARTS[i + 1] - 1 { + return Error(ErrorKind::GroupLength { + group: i, + len: group_bounds[i] - BLOCK_STARTS[i], + index: offset + BLOCK_STARTS[i] + 1, + }); + } + } + + // The last group must be too long + Error(ErrorKind::GroupLength { + group: 4, + len: s.len() - BLOCK_STARTS[4], + index: offset + BLOCK_STARTS[4] + 1, + }) + } + } +} + +impl fmt::Display for Error { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self.0 { + ErrorKind::Char { + character, index, .. + } => { + write!(f, "invalid character: expected an optional prefix of `urn:uuid:` followed by [0-9a-zA-Z], found `{}` at {}", character, index) + } + ErrorKind::SimpleLength { len } => { + write!( + f, + "invalid length: expected length 32 for simple format, found {}", + len + ) + } + ErrorKind::GroupCount { count } => { + write!(f, "invalid group count: expected 5, found {}", count) + } + ErrorKind::GroupLength { group, len, .. } => { + let expected = [8, 4, 4, 4, 12][group]; + write!( + f, + "invalid group length in group {}: expected {}, found {}", + group, expected, len + ) + } + } + } +} diff --git a/src/lib.rs b/src/lib.rs new file mode 100644 index 0000000..e1d517b --- /dev/null +++ b/src/lib.rs @@ -0,0 +1,84 @@ +//! Implementation details for the `uuid!` macro. +//! +//! This crate is not meant to be used directly. Instead, +//! you can use the `macro-diagnostics` feature of `uuid`: +//! +//! ```toml +//! [dependencies.uuid] +//! features = ["macro-diagnostics"] +//! ``` + +use proc_macro::TokenStream; +use proc_macro2::TokenStream as TokenStream2; +use quote::{quote, quote_spanned}; +use std::fmt; +use syn::{spanned::Spanned, LitStr}; + +mod error; +mod parser; + +#[proc_macro] +#[doc(hidden)] +pub fn parse_lit(input: TokenStream) -> TokenStream { + build_uuid(input.clone()).unwrap_or_else(|e| { + let msg = e.to_string(); + let span = match e { + Error::UuidParse(lit, error::Error(error::ErrorKind::Char { character, index })) => { + let mut bytes = character as u32; + let mut width = 0; + while bytes != 0 { + bytes >>= 4; + width += 1; + } + let mut s = proc_macro2::Literal::string(""); + s.set_span(lit.span()); + s.subspan(index..index + width - 1) + } + Error::UuidParse( + lit, + error::Error(error::ErrorKind::GroupLength { index, len, .. }), + ) => { + let mut s = proc_macro2::Literal::string(""); + s.set_span(lit.span()); + s.subspan(index..index + len) + } + _ => None, + } + .unwrap_or_else(|| TokenStream2::from(input).span()); + + TokenStream::from(quote_spanned! {span=> + compile_error!(#msg) + }) + }) +} + +enum Error { + NonStringLiteral, + UuidParse(LitStr, error::Error), +} + +impl fmt::Display for Error { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match *self { + Error::NonStringLiteral => f.write_str("expected string literal"), + Error::UuidParse(_, ref e) => write!(f, "{}", e), + } + } +} + +fn build_uuid(input: TokenStream) -> Result { + let str_lit = match syn::parse::(input) { + Ok(syn::Lit::Str(literal)) => literal, + _ => return Err(Error::NonStringLiteral), + }; + + let bytes = + parser::try_parse(&str_lit.value()).map_err(|e| Error::UuidParse(str_lit, e.into_err()))?; + + let tokens = bytes + .iter() + .map(|byte| quote! { #byte, }) + .collect::(); + + Ok(quote! {[#tokens]}.into()) +} diff --git a/src/parser.rs b/src/parser.rs new file mode 100644 index 0000000..f6a12b7 --- /dev/null +++ b/src/parser.rs @@ -0,0 +1,152 @@ +// Copyright 2013-2014 The Rust Project Developers. +// Copyright 2018 The Uuid Project Developers. +// +// See the COPYRIGHT file at the top-level directory of this distribution. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +use crate::error::InvalidUuid; + +#[inline] +pub const fn try_parse(input: &str) -> Result<[u8; 16], InvalidUuid> { + let result = match (input.len(), input.as_bytes()) { + // Inputs of 32 bytes must be a non-hyphenated UUID + (32, s) => parse_simple(s), + // Hyphenated UUIDs may be wrapped in various ways: + // - `{UUID}` for braced UUIDs + // - `urn:uuid:UUID` for URNs + // - `UUID` for a regular hyphenated UUID + (36, s) + | (38, [b'{', s @ .., b'}']) + | (45, [b'u', b'r', b'n', b':', b'u', b'u', b'i', b'd', b':', s @ ..]) => { + parse_hyphenated(s) + } + // Any other shaped input is immediately invalid + _ => Err(()), + }; + + match result { + Ok(b) => Ok(b), + Err(()) => Err(InvalidUuid(input)), + } +} + +#[inline] +const fn parse_simple(s: &[u8]) -> Result<[u8; 16], ()> { + // This length check here removes all other bounds + // checks in this function + if s.len() != 32 { + return Err(()); + } + + let mut buf: [u8; 16] = [0; 16]; + let mut i = 0; + + while i < 16 { + // Convert a two-char hex value (like `A8`) + // into a byte (like `10101000`) + let h1 = HEX_TABLE[s[i * 2] as usize]; + let h2 = HEX_TABLE[s[i * 2 + 1] as usize]; + + // We use `0xff` as a sentinel value to indicate + // an invalid hex character sequence (like the letter `G`) + if h1 | h2 == 0xff { + return Err(()); + } + + // The upper nibble needs to be shifted into position + // to produce the final byte value + buf[i] = SHL4_TABLE[h1 as usize] | h2; + i += 1; + } + + Ok(buf) +} + +#[inline] +const fn parse_hyphenated(s: &[u8]) -> Result<[u8; 16], ()> { + // This length check here removes all other bounds + // checks in this function + if s.len() != 36 { + return Err(()); + } + + // We look at two hex-encoded values (4 chars) at a time because + // that's the size of the smallest group in a hyphenated UUID. + // The indexes we're interested in are: + // + // uuid : 936da01f-9abd-4d9d-80c7-02af85c822a8 + // | | || || || || | | + // hyphens : | | 8| 13| 18| 23| | | + // positions: 0 4 9 14 19 24 28 32 + + // First, ensure the hyphens appear in the right places + match [s[8], s[13], s[18], s[23]] { + [b'-', b'-', b'-', b'-'] => {} + _ => return Err(()), + } + + let positions: [u8; 8] = [0, 4, 9, 14, 19, 24, 28, 32]; + let mut buf: [u8; 16] = [0; 16]; + let mut j = 0; + + while j < 8 { + let i = positions[j]; + + // The decoding here is the same as the simple case + // We're just dealing with two values instead of one + let h1 = HEX_TABLE[s[i as usize] as usize]; + let h2 = HEX_TABLE[s[(i + 1) as usize] as usize]; + let h3 = HEX_TABLE[s[(i + 2) as usize] as usize]; + let h4 = HEX_TABLE[s[(i + 3) as usize] as usize]; + + if h1 | h2 | h3 | h4 == 0xff { + return Err(()); + } + + buf[j * 2] = SHL4_TABLE[h1 as usize] | h2; + buf[j * 2 + 1] = SHL4_TABLE[h3 as usize] | h4; + j += 1; + } + + Ok(buf) +} + +const HEX_TABLE: &[u8; 256] = &{ + let mut buf = [0; 256]; + let mut i: u8 = 0; + + loop { + buf[i as usize] = match i { + b'0'..=b'9' => i - b'0', + b'a'..=b'f' => i - b'a' + 10, + b'A'..=b'F' => i - b'A' + 10, + _ => 0xff, + }; + + if i == 255 { + break buf; + } + + i += 1 + } +}; + +const SHL4_TABLE: &[u8; 256] = &{ + let mut buf = [0; 256]; + let mut i: u8 = 0; + + loop { + buf[i as usize] = i.wrapping_shl(4); + + if i == 255 { + break buf; + } + + i += 1; + } +};