Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

1 files changed, 612 insertions, 0 deletions

diff --git a/vendor/gimli/src/leb128.rs b/vendor/gimli/src/leb128.rs
new file mode 100644
index 0000000..de81cfd
--- /dev/null
+++ b/vendor/gimli/src/leb128.rs
@@ -0,0 +1,612 @@
+//! Read and write DWARF's "Little Endian Base 128" (LEB128) variable length
+//! integer encoding.
+//!
+//! The implementation is a direct translation of the psuedocode in the DWARF 4
+//! standard's appendix C.
+//!
+//! Read and write signed integers:
+//!
+//! ```
+//! # #[cfg(all(feature = "read", feature = "write"))] {
+//! use gimli::{EndianSlice, NativeEndian, leb128};
+//!
+//! let mut buf = [0; 1024];
+//!
+//! // Write to anything that implements `std::io::Write`.
+//! {
+//!     let mut writable = &mut buf[..];
+//!     leb128::write::signed(&mut writable, -12345).expect("Should write number");
+//! }
+//!
+//! // Read from anything that implements `gimli::Reader`.
+//! let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+//! let val = leb128::read::signed(&mut readable).expect("Should read number");
+//! assert_eq!(val, -12345);
+//! # }
+//! ```
+//!
+//! Or read and write unsigned integers:
+//!
+//! ```
+//! # #[cfg(all(feature = "read", feature = "write"))] {
+//! use gimli::{EndianSlice, NativeEndian, leb128};
+//!
+//! let mut buf = [0; 1024];
+//!
+//! {
+//!     let mut writable = &mut buf[..];
+//!     leb128::write::unsigned(&mut writable, 98765).expect("Should write number");
+//! }
+//!
+//! let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+//! let val = leb128::read::unsigned(&mut readable).expect("Should read number");
+//! assert_eq!(val, 98765);
+//! # }
+//! ```
+
+const CONTINUATION_BIT: u8 = 1 << 7;
+#[cfg(feature = "read-core")]
+const SIGN_BIT: u8 = 1 << 6;
+
+#[inline]
+fn low_bits_of_byte(byte: u8) -> u8 {
+    byte & !CONTINUATION_BIT
+}
+
+#[inline]
+#[allow(dead_code)]
+fn low_bits_of_u64(val: u64) -> u8 {
+    let byte = val & u64::from(core::u8::MAX);
+    low_bits_of_byte(byte as u8)
+}
+
+/// A module for reading signed and unsigned integers that have been LEB128
+/// encoded.
+#[cfg(feature = "read-core")]
+pub mod read {
+    use super::{low_bits_of_byte, CONTINUATION_BIT, SIGN_BIT};
+    use crate::read::{Error, Reader, Result};
+
+    /// Read bytes until the LEB128 continuation bit is not set.
+    pub fn skip<R: Reader>(r: &mut R) -> Result<()> {
+        loop {
+            let byte = r.read_u8()?;
+            if byte & CONTINUATION_BIT == 0 {
+                return Ok(());
+            }
+        }
+    }
+
+    /// Read an unsigned LEB128 number from the given `Reader` and
+    /// return it or an error if reading failed.
+    pub fn unsigned<R: Reader>(r: &mut R) -> Result<u64> {
+        let mut result = 0;
+        let mut shift = 0;
+
+        loop {
+            let byte = r.read_u8()?;
+            if shift == 63 && byte != 0x00 && byte != 0x01 {
+                return Err(Error::BadUnsignedLeb128);
+            }
+
+            let low_bits = u64::from(low_bits_of_byte(byte));
+            result |= low_bits << shift;
+
+            if byte & CONTINUATION_BIT == 0 {
+                return Ok(result);
+            }
+
+            shift += 7;
+        }
+    }
+
+    /// Read an LEB128 u16 from the given `Reader` and
+    /// return it or an error if reading failed.
+    pub fn u16<R: Reader>(r: &mut R) -> Result<u16> {
+        let byte = r.read_u8()?;
+        let mut result = u16::from(low_bits_of_byte(byte));
+        if byte & CONTINUATION_BIT == 0 {
+            return Ok(result);
+        }
+
+        let byte = r.read_u8()?;
+        result |= u16::from(low_bits_of_byte(byte)) << 7;
+        if byte & CONTINUATION_BIT == 0 {
+            return Ok(result);
+        }
+
+        let byte = r.read_u8()?;
+        if byte > 0x03 {
+            return Err(Error::BadUnsignedLeb128);
+        }
+        result += u16::from(byte) << 14;
+        Ok(result)
+    }
+
+    /// Read a signed LEB128 number from the given `Reader` and
+    /// return it or an error if reading failed.
+    pub fn signed<R: Reader>(r: &mut R) -> Result<i64> {
+        let mut result = 0;
+        let mut shift = 0;
+        let size = 64;
+        let mut byte;
+
+        loop {
+            byte = r.read_u8()?;
+            if shift == 63 && byte != 0x00 && byte != 0x7f {
+                return Err(Error::BadSignedLeb128);
+            }
+
+            let low_bits = i64::from(low_bits_of_byte(byte));
+            result |= low_bits << shift;
+            shift += 7;
+
+            if byte & CONTINUATION_BIT == 0 {
+                break;
+            }
+        }
+
+        if shift < size && (SIGN_BIT & byte) == SIGN_BIT {
+            // Sign extend the result.
+            result |= !0 << shift;
+        }
+
+        Ok(result)
+    }
+}
+
+/// A module for writing integers encoded as LEB128.
+#[cfg(feature = "write")]
+pub mod write {
+    use super::{low_bits_of_u64, CONTINUATION_BIT};
+    use std::io;
+
+    /// Write the given unsigned number using the LEB128 encoding to the given
+    /// `std::io::Write`able. Returns the number of bytes written to `w`, or an
+    /// error if writing failed.
+    pub fn unsigned<W>(w: &mut W, mut val: u64) -> Result<usize, io::Error>
+    where
+        W: io::Write,
+    {
+        let mut bytes_written = 0;
+        loop {
+            let mut byte = low_bits_of_u64(val);
+            val >>= 7;
+            if val != 0 {
+                // More bytes to come, so set the continuation bit.
+                byte |= CONTINUATION_BIT;
+            }
+
+            let buf = [byte];
+            w.write_all(&buf)?;
+            bytes_written += 1;
+
+            if val == 0 {
+                return Ok(bytes_written);
+            }
+        }
+    }
+
+    /// Return the size of the LEB128 encoding of the given unsigned number.
+    pub fn uleb128_size(mut val: u64) -> usize {
+        let mut size = 0;
+        loop {
+            val >>= 7;
+            size += 1;
+            if val == 0 {
+                return size;
+            }
+        }
+    }
+
+    /// Write the given signed number using the LEB128 encoding to the given
+    /// `std::io::Write`able. Returns the number of bytes written to `w`, or an
+    /// error if writing failed.
+    pub fn signed<W>(w: &mut W, mut val: i64) -> Result<usize, io::Error>
+    where
+        W: io::Write,
+    {
+        let mut bytes_written = 0;
+        loop {
+            let mut byte = val as u8;
+            // Keep the sign bit for testing
+            val >>= 6;
+            let done = val == 0 || val == -1;
+            if done {
+                byte &= !CONTINUATION_BIT;
+            } else {
+                // Remove the sign bit
+                val >>= 1;
+                // More bytes to come, so set the continuation bit.
+                byte |= CONTINUATION_BIT;
+            }
+
+            let buf = [byte];
+            w.write_all(&buf)?;
+            bytes_written += 1;
+
+            if done {
+                return Ok(bytes_written);
+            }
+        }
+    }
+
+    /// Return the size of the LEB128 encoding of the given signed number.
+    pub fn sleb128_size(mut val: i64) -> usize {
+        let mut size = 0;
+        loop {
+            val >>= 6;
+            let done = val == 0 || val == -1;
+            val >>= 1;
+            size += 1;
+            if done {
+                return size;
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+#[cfg(all(feature = "read", feature = "write"))]
+mod tests {
+    use super::{low_bits_of_byte, low_bits_of_u64, read, write, CONTINUATION_BIT};
+    use crate::endianity::NativeEndian;
+    use crate::read::{EndianSlice, Error, ReaderOffsetId};
+
+    trait ResultExt {
+        fn map_eof(self, input: &[u8]) -> Self;
+    }
+
+    impl<T> ResultExt for Result<T, Error> {
+        fn map_eof(self, input: &[u8]) -> Self {
+            match self {
+                Err(Error::UnexpectedEof(id)) => {
+                    let id = ReaderOffsetId(id.0 - input.as_ptr() as u64);
+                    Err(Error::UnexpectedEof(id))
+                }
+                r => r,
+            }
+        }
+    }
+
+    #[test]
+    fn test_low_bits_of_byte() {
+        for i in 0..127 {
+            assert_eq!(i, low_bits_of_byte(i));
+            assert_eq!(i, low_bits_of_byte(i | CONTINUATION_BIT));
+        }
+    }
+
+    #[test]
+    fn test_low_bits_of_u64() {
+        for i in 0u64..127 {
+            assert_eq!(i as u8, low_bits_of_u64(1 << 16 | i));
+            assert_eq!(
+                i as u8,
+                low_bits_of_u64(i << 16 | i | (u64::from(CONTINUATION_BIT)))
+            );
+        }
+    }
+
+    // Examples from the DWARF 4 standard, section 7.6, figure 22.
+    #[test]
+    fn test_read_unsigned() {
+        let buf = [2u8];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            2,
+            read::unsigned(&mut readable).expect("Should read number")
+        );
+
+        let buf = [127u8];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            127,
+            read::unsigned(&mut readable).expect("Should read number")
+        );
+
+        let buf = [CONTINUATION_BIT, 1];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            128,
+            read::unsigned(&mut readable).expect("Should read number")
+        );
+
+        let buf = [1u8 | CONTINUATION_BIT, 1];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            129,
+            read::unsigned(&mut readable).expect("Should read number")
+        );
+
+        let buf = [2u8 | CONTINUATION_BIT, 1];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            130,
+            read::unsigned(&mut readable).expect("Should read number")
+        );
+
+        let buf = [57u8 | CONTINUATION_BIT, 100];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            12857,
+            read::unsigned(&mut readable).expect("Should read number")
+        );
+    }
+
+    // Examples from the DWARF 4 standard, section 7.6, figure 23.
+    #[test]
+    fn test_read_signed() {
+        let buf = [2u8];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(2, read::signed(&mut readable).expect("Should read number"));
+
+        let buf = [0x7eu8];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(-2, read::signed(&mut readable).expect("Should read number"));
+
+        let buf = [127u8 | CONTINUATION_BIT, 0];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            127,
+            read::signed(&mut readable).expect("Should read number")
+        );
+
+        let buf = [1u8 | CONTINUATION_BIT, 0x7f];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            -127,
+            read::signed(&mut readable).expect("Should read number")
+        );
+
+        let buf = [CONTINUATION_BIT, 1];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            128,
+            read::signed(&mut readable).expect("Should read number")
+        );
+
+        let buf = [CONTINUATION_BIT, 0x7f];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            -128,
+            read::signed(&mut readable).expect("Should read number")
+        );
+
+        let buf = [1u8 | CONTINUATION_BIT, 1];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            129,
+            read::signed(&mut readable).expect("Should read number")
+        );
+
+        let buf = [0x7fu8 | CONTINUATION_BIT, 0x7e];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            -129,
+            read::signed(&mut readable).expect("Should read number")
+        );
+    }
+
+    #[test]
+    fn test_read_signed_63_bits() {
+        let buf = [
+            CONTINUATION_BIT,
+            CONTINUATION_BIT,
+            CONTINUATION_BIT,
+            CONTINUATION_BIT,
+            CONTINUATION_BIT,
+            CONTINUATION_BIT,
+            CONTINUATION_BIT,
+            CONTINUATION_BIT,
+            0x40,
+        ];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            -0x4000_0000_0000_0000,
+            read::signed(&mut readable).expect("Should read number")
+        );
+    }
+
+    #[test]
+    fn test_read_unsigned_not_enough_data() {
+        let buf = [CONTINUATION_BIT];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            read::unsigned(&mut readable).map_eof(&buf),
+            Err(Error::UnexpectedEof(ReaderOffsetId(1)))
+        );
+    }
+
+    #[test]
+    fn test_read_signed_not_enough_data() {
+        let buf = [CONTINUATION_BIT];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            read::signed(&mut readable).map_eof(&buf),
+            Err(Error::UnexpectedEof(ReaderOffsetId(1)))
+        );
+    }
+
+    #[test]
+    fn test_write_unsigned_not_enough_space() {
+        let mut buf = [0; 1];
+        let mut writable = &mut buf[..];
+        match write::unsigned(&mut writable, 128) {
+            Err(e) => assert_eq!(e.kind(), std::io::ErrorKind::WriteZero),
+            otherwise => panic!("Unexpected: {:?}", otherwise),
+        }
+    }
+
+    #[test]
+    fn test_write_signed_not_enough_space() {
+        let mut buf = [0; 1];
+        let mut writable = &mut buf[..];
+        match write::signed(&mut writable, 128) {
+            Err(e) => assert_eq!(e.kind(), std::io::ErrorKind::WriteZero),
+            otherwise => panic!("Unexpected: {:?}", otherwise),
+        }
+    }
+
+    #[test]
+    fn dogfood_signed() {
+        fn inner(i: i64) {
+            let mut buf = [0u8; 1024];
+
+            {
+                let mut writable = &mut buf[..];
+                write::signed(&mut writable, i).expect("Should write signed number");
+            }
+
+            let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+            let result = read::signed(&mut readable).expect("Should be able to read it back again");
+            assert_eq!(i, result);
+        }
+        for i in -513..513 {
+            inner(i);
+        }
+        inner(core::i64::MIN);
+    }
+
+    #[test]
+    fn dogfood_unsigned() {
+        for i in 0..1025 {
+            let mut buf = [0u8; 1024];
+
+            {
+                let mut writable = &mut buf[..];
+                write::unsigned(&mut writable, i).expect("Should write signed number");
+            }
+
+            let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+            let result =
+                read::unsigned(&mut readable).expect("Should be able to read it back again");
+            assert_eq!(i, result);
+        }
+    }
+
+    #[test]
+    fn test_read_unsigned_overflow() {
+        let buf = [
+            2u8 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            1,
+        ];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert!(read::unsigned(&mut readable).is_err());
+    }
+
+    #[test]
+    fn test_read_signed_overflow() {
+        let buf = [
+            2u8 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            2 | CONTINUATION_BIT,
+            1,
+        ];
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert!(read::signed(&mut readable).is_err());
+    }
+
+    #[test]
+    fn test_read_multiple() {
+        let buf = [2u8 | CONTINUATION_BIT, 1u8, 1u8];
+
+        let mut readable = EndianSlice::new(&buf[..], NativeEndian);
+        assert_eq!(
+            read::unsigned(&mut readable).expect("Should read first number"),
+            130u64
+        );
+        assert_eq!(
+            read::unsigned(&mut readable).expect("Should read first number"),
+            1u64
+        );
+    }
+
+    #[test]
+    fn test_read_u16() {
+        for (buf, val) in [
+            (&[2][..], 2),
+            (&[0x7f][..], 0x7f),
+            (&[0x80, 1][..], 0x80),
+            (&[0x81, 1][..], 0x81),
+            (&[0x82, 1][..], 0x82),
+            (&[0xff, 0x7f][..], 0x3fff),
+            (&[0x80, 0x80, 1][..], 0x4000),
+            (&[0xff, 0xff, 1][..], 0x7fff),
+            (&[0xff, 0xff, 3][..], 0xffff),
+        ]
+        .iter()
+        {
+            let mut readable = EndianSlice::new(buf, NativeEndian);
+            assert_eq!(*val, read::u16(&mut readable).expect("Should read number"));
+        }
+
+        for buf in [
+            &[0x80][..],
+            &[0x80, 0x80][..],
+            &[0x80, 0x80, 4][..],
+            &[0x80, 0x80, 0x80, 3][..],
+        ]
+        .iter()
+        {
+            let mut readable = EndianSlice::new(buf, NativeEndian);
+            assert!(read::u16(&mut readable).is_err(), "{:?}", buf);
+        }
+    }
+}