Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/proc-macro-srv/src/dylib/version.rs')
| -rw-r--r-- | crates/proc-macro-srv/src/dylib/version.rs | 168 |
1 files changed, 0 insertions, 168 deletions
diff --git a/crates/proc-macro-srv/src/dylib/version.rs b/crates/proc-macro-srv/src/dylib/version.rs deleted file mode 100644 index 209693b4da..0000000000 --- a/crates/proc-macro-srv/src/dylib/version.rs +++ /dev/null @@ -1,168 +0,0 @@ -//! Reading proc-macro rustc version information from binary data - -use std::io::{self, Read}; - -use object::read::{Object, ObjectSection}; - -#[derive(Debug)] -pub struct RustCInfo { - #[allow(dead_code)] - pub version: (usize, usize, usize), - #[allow(dead_code)] - pub channel: String, - #[allow(dead_code)] - pub commit: Option<String>, - #[allow(dead_code)] - pub date: Option<String>, - // something like "rustc 1.58.1 (db9d1b20b 2022-01-20)" - pub version_string: String, -} - -/// Read rustc dylib information -pub fn read_dylib_info(obj: &object::File<'_>) -> io::Result<RustCInfo> { - macro_rules! err { - ($e:literal) => { - io::Error::new(io::ErrorKind::InvalidData, $e) - }; - } - - let ver_str = read_version(obj)?; - let mut items = ver_str.split_whitespace(); - let tag = items.next().ok_or_else(|| err!("version format error"))?; - if tag != "rustc" { - return Err(err!("no rustc tag")); - } - - let version_part = items.next().ok_or_else(|| err!("no version string"))?; - let mut version_parts = version_part.split('-'); - let version = version_parts.next().ok_or_else(|| err!("no version"))?; - let channel = version_parts.next().unwrap_or_default().to_owned(); - - let commit = match items.next() { - Some(commit) => { - match commit.len() { - 0 => None, - _ => Some(commit[1..].to_string() /* remove ( */), - } - } - None => None, - }; - let date = match items.next() { - Some(date) => { - match date.len() { - 0 => None, - _ => Some(date[0..date.len() - 2].to_string() /* remove ) */), - } - } - None => None, - }; - - let version_numbers = version - .split('.') - .map(|it| it.parse::<usize>()) - .collect::<Result<Vec<_>, _>>() - .map_err(|_| err!("version number error"))?; - - if version_numbers.len() != 3 { - return Err(err!("version number format error")); - } - let version = (version_numbers[0], version_numbers[1], version_numbers[2]); - - Ok(RustCInfo { version, channel, commit, date, version_string: ver_str }) -} - -/// This is used inside read_version() to locate the ".rustc" section -/// from a proc macro crate's binary file. -fn read_section<'a>(obj: &object::File<'a>, section_name: &str) -> io::Result<&'a [u8]> { - obj.section_by_name(section_name) - .ok_or_else(|| io::Error::new(io::ErrorKind::InvalidData, "section read error"))? - .data() - .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e)) -} - -/// Check the version of rustc that was used to compile a proc macro crate's -/// binary file. -/// -/// A proc macro crate binary's ".rustc" section has following byte layout: -/// * [b'r',b'u',b's',b't',0,0,0,5] is the first 8 bytes -/// * ff060000 734e6150 is followed, it's the snappy format magic bytes, -/// means bytes from here (including this sequence) are compressed in -/// snappy compression format. Version info is inside here, so decompress -/// this. -/// -/// The bytes you get after decompressing the snappy format portion has -/// following layout: -/// * [b'r',b'u',b's',b't',0,0,0,5] is the first 8 bytes(again) -/// * [crate root bytes] next 8 bytes (4 in old versions) is to store -/// crate root position, according to rustc's source code comment -/// * [length byte] next 1 byte tells us how many bytes we should read next -/// for the version string's utf8 bytes -/// * [version string bytes encoded in utf8] <- GET THIS BOI -/// * [some more bytes that we don't really care but about still there] :-) -/// -/// Check this issue for more about the bytes layout: -/// <https://github.com/rust-lang/rust-analyzer/issues/6174> -pub fn read_version(obj: &object::File<'_>) -> io::Result<String> { - let dot_rustc = read_section(obj, ".rustc")?; - - // check if magic is valid - if &dot_rustc[0..4] != b"rust" { - return Err(io::Error::new( - io::ErrorKind::InvalidData, - format!("unknown metadata magic, expected `rust`, found `{:?}`", &dot_rustc[0..4]), - )); - } - let version = u32::from_be_bytes([dot_rustc[4], dot_rustc[5], dot_rustc[6], dot_rustc[7]]); - // Last version with breaking changes is: - // https://github.com/rust-lang/rust/commit/b94cfefc860715fb2adf72a6955423d384c69318 - let (mut metadata_portion, bytes_before_version) = match version { - 8 => { - let len_bytes = &dot_rustc[8..12]; - let data_len = u32::from_be_bytes(len_bytes.try_into().unwrap()) as usize; - (&dot_rustc[12..data_len + 12], 13) - } - 9 | 10 => { - let len_bytes = &dot_rustc[8..16]; - let data_len = u64::from_le_bytes(len_bytes.try_into().unwrap()) as usize; - (&dot_rustc[16..data_len + 12], 17) - } - _ => { - return Err(io::Error::new( - io::ErrorKind::InvalidData, - format!("unsupported metadata version {version}"), - )); - } - }; - - // We're going to skip over the bytes before the version string, so basically: - // 8 bytes for [b'r',b'u',b's',b't',0,0,0,5] - // 4 or 8 bytes for [crate root bytes] - // 1 byte for length of version string - // so 13 or 17 bytes in total, and we should check the last of those bytes - // to know the length - let mut bytes = [0u8; 17]; - metadata_portion.read_exact(&mut bytes[..bytes_before_version])?; - let length = bytes[bytes_before_version - 1]; - - let mut version_string_utf8 = vec![0u8; length as usize]; - metadata_portion.read_exact(&mut version_string_utf8)?; - let version_string = String::from_utf8(version_string_utf8); - version_string.map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e)) -} - -#[test] -fn test_version_check() { - let info = read_dylib_info( - &object::File::parse(&*std::fs::read(crate::proc_macro_test_dylib_path()).unwrap()) - .unwrap(), - ) - .unwrap(); - - assert_eq!( - info.version_string, - crate::RUSTC_VERSION_STRING, - "sysroot ABI mismatch: dylib rustc version (read from .rustc section): {:?} != proc-macro-srv version (read from 'rustc --version'): {:?}", - info.version_string, - crate::RUSTC_VERSION_STRING, - ); -} |