diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/rust/bhttp/src/rw.rs | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream.tar.xz firefox-esr-upstream.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/bhttp/src/rw.rs')
-rw-r--r-- | third_party/rust/bhttp/src/rw.rs | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/third_party/rust/bhttp/src/rw.rs b/third_party/rust/bhttp/src/rw.rs new file mode 100644 index 0000000000..8fee16daa9 --- /dev/null +++ b/third_party/rust/bhttp/src/rw.rs @@ -0,0 +1,106 @@ +use crate::err::Res; +#[cfg(feature = "read-bhttp")] +use crate::{err::Error, ReadSeek}; +#[cfg(feature = "read-bhttp")] +use std::borrow::BorrowMut; +use std::{convert::TryFrom, io}; + +#[cfg(feature = "write-bhttp")] +#[allow(clippy::cast_possible_truncation)] +fn write_uint(n: u8, v: impl Into<u64>, w: &mut impl io::Write) -> Res<()> { + let v = v.into(); + assert!(n > 0 && usize::from(n) < std::mem::size_of::<u64>()); + for i in 0..n { + w.write_all(&[((v >> (8 * (n - i - 1))) & 0xff) as u8])?; + } + Ok(()) +} + +#[cfg(feature = "write-bhttp")] +pub fn write_varint(v: impl Into<u64>, w: &mut impl io::Write) -> Res<()> { + let v = v.into(); + match () { + _ if v < (1 << 6) => write_uint(1, v, w), + _ if v < (1 << 14) => write_uint(2, v | (1 << 14), w), + _ if v < (1 << 30) => write_uint(4, v | (2 << 30), w), + _ if v < (1 << 62) => write_uint(8, v | (3 << 62), w), + _ => panic!("Varint value too large"), + } +} + +#[cfg(feature = "write-bhttp")] +pub fn write_len(len: usize, w: &mut impl io::Write) -> Res<()> { + write_varint(u64::try_from(len).unwrap(), w) +} + +#[cfg(feature = "write-bhttp")] +pub fn write_vec(v: &[u8], w: &mut impl io::Write) -> Res<()> { + write_len(v.len(), w)?; + w.write_all(v)?; + Ok(()) +} + +#[cfg(feature = "read-bhttp")] +fn read_uint<T, R>(n: usize, r: &mut T) -> Res<Option<u64>> +where + T: BorrowMut<R> + ?Sized, + R: ReadSeek + ?Sized, +{ + let mut buf = [0; 7]; + let count = r.borrow_mut().read(&mut buf[..n])?; + if count == 0 { + return Ok(None); + } else if count < n { + return Err(Error::Truncated); + } + let mut v = 0; + for i in &buf[..n] { + v = (v << 8) | u64::from(*i); + } + Ok(Some(v)) +} + +#[cfg(feature = "read-bhttp")] +pub fn read_varint<T, R>(r: &mut T) -> Res<Option<u64>> +where + T: BorrowMut<R> + ?Sized, + R: ReadSeek + ?Sized, +{ + if let Some(b1) = read_uint(1, r)? { + Ok(Some(match b1 >> 6 { + 0 => b1 & 0x3f, + 1 => ((b1 & 0x3f) << 8) | read_uint(1, r)?.ok_or(Error::Truncated)?, + 2 => ((b1 & 0x3f) << 24) | read_uint(3, r)?.ok_or(Error::Truncated)?, + 3 => ((b1 & 0x3f) << 56) | read_uint(7, r)?.ok_or(Error::Truncated)?, + _ => unreachable!(), + })) + } else { + Ok(None) + } +} + +#[cfg(feature = "read-bhttp")] +pub fn read_vec<T, R>(r: &mut T) -> Res<Option<Vec<u8>>> +where + T: BorrowMut<R> + ?Sized, + R: ReadSeek + ?Sized, +{ + use std::io::SeekFrom; + + if let Some(len) = read_varint(r)? { + // Check that the input contains enough data. Before allocating. + let r = r.borrow_mut(); + let pos = r.stream_position()?; + let end = r.seek(SeekFrom::End(0))?; + if end - pos < len { + return Err(Error::Truncated); + } + let _ = r.seek(SeekFrom::Start(pos))?; + + let mut v = vec![0; usize::try_from(len)?]; + r.read_exact(&mut v)?; + Ok(Some(v)) + } else { + Ok(None) + } +} |