Initial vendor packages

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

1 files changed, 247 insertions, 0 deletions

diff --git a/vendor/bitflags/src/parser.rs b/vendor/bitflags/src/parser.rs
new file mode 100644
index 0000000..130dc2e
--- /dev/null
+++ b/vendor/bitflags/src/parser.rs
@@ -0,0 +1,247 @@
+/*!
+Parsing flags from text.
+
+Format and parse a flags value as text using the following grammar:
+
+- _Flags:_ (_Whitespace_ _Flag_ _Whitespace_)`|`*
+- _Flag:_ _Name_ | _Hex Number_
+- _Name:_ The name of any defined flag
+- _Hex Number_: `0x`([0-9a-fA-F])*
+- _Whitespace_: (\s)*
+
+As an example, this is how `Flags::A | Flags::B | 0x0c` can be represented as text:
+
+```text
+A | B | 0x0c
+```
+
+Alternatively, it could be represented without whitespace:
+
+```text
+A|B|0x0C
+```
+
+Note that identifiers are *case-sensitive*, so the following is *not equivalent*:
+
+```text
+a|b|0x0C
+```
+*/
+
+#![allow(clippy::let_unit_value)]
+
+use core::fmt::{self, Write};
+
+use crate::{Bits, Flags};
+
+/**
+Write a flags value as text.
+
+Any bits that aren't part of a contained flag will be formatted as a hex number.
+*/
+pub fn to_writer<B: Flags>(flags: &B, mut writer: impl Write) -> Result<(), fmt::Error>
+where
+    B::Bits: WriteHex,
+{
+    // A formatter for bitflags that produces text output like:
+    //
+    // A | B | 0xf6
+    //
+    // The names of set flags are written in a bar-separated-format,
+    // followed by a hex number of any remaining bits that are set
+    // but don't correspond to any flags.
+
+    // Iterate over known flag values
+    let mut first = true;
+    let mut iter = flags.iter_names();
+    for (name, _) in &mut iter {
+        if !first {
+            writer.write_str(" | ")?;
+        }
+
+        first = false;
+        writer.write_str(name)?;
+    }
+
+    // Append any extra bits that correspond to flags to the end of the format
+    let remaining = iter.remaining().bits();
+    if remaining != B::Bits::EMPTY {
+        if !first {
+            writer.write_str(" | ")?;
+        }
+
+        writer.write_str("0x")?;
+        remaining.write_hex(writer)?;
+    }
+
+    fmt::Result::Ok(())
+}
+
+pub(crate) struct AsDisplay<'a, B>(pub(crate) &'a B);
+
+impl<'a, B: Flags> fmt::Display for AsDisplay<'a, B>
+where
+    B::Bits: WriteHex,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        to_writer(self.0, f)
+    }
+}
+
+/**
+Parse a flags value from text.
+
+This function will fail on any names that don't correspond to defined flags.
+Unknown bits will be retained.
+*/
+pub fn from_str<B: Flags>(input: &str) -> Result<B, ParseError>
+where
+    B::Bits: ParseHex,
+{
+    let mut parsed_flags = B::empty();
+
+    // If the input is empty then return an empty set of flags
+    if input.trim().is_empty() {
+        return Ok(parsed_flags);
+    }
+
+    for flag in input.split('|') {
+        let flag = flag.trim();
+
+        // If the flag is empty then we've got missing input
+        if flag.is_empty() {
+            return Err(ParseError::empty_flag());
+        }
+
+        // If the flag starts with `0x` then it's a hex number
+        // Parse it directly to the underlying bits type
+        let parsed_flag = if let Some(flag) = flag.strip_prefix("0x") {
+            let bits =
+                <B::Bits>::parse_hex(flag).map_err(|_| ParseError::invalid_hex_flag(flag))?;
+
+            B::from_bits_retain(bits)
+        }
+        // Otherwise the flag is a name
+        // The generated flags type will determine whether
+        // or not it's a valid identifier
+        else {
+            B::from_name(flag).ok_or_else(|| ParseError::invalid_named_flag(flag))?
+        };
+
+        parsed_flags.insert(parsed_flag);
+    }
+
+    Ok(parsed_flags)
+}
+
+/**
+Encode a value as a hex string.
+
+Implementors of this trait should not write the `0x` prefix.
+*/
+pub trait WriteHex {
+    /// Write the value as hex.
+    fn write_hex<W: fmt::Write>(&self, writer: W) -> fmt::Result;
+}
+
+/**
+Parse a value from a hex string.
+*/
+pub trait ParseHex {
+    /// Parse the value from hex.
+    fn parse_hex(input: &str) -> Result<Self, ParseError>
+    where
+        Self: Sized;
+}
+
+/// An error encountered while parsing flags from text.
+#[derive(Debug)]
+pub struct ParseError(ParseErrorKind);
+
+#[derive(Debug)]
+#[allow(clippy::enum_variant_names)]
+enum ParseErrorKind {
+    EmptyFlag,
+    InvalidNamedFlag {
+        #[cfg(not(feature = "std"))]
+        got: (),
+        #[cfg(feature = "std")]
+        got: String,
+    },
+    InvalidHexFlag {
+        #[cfg(not(feature = "std"))]
+        got: (),
+        #[cfg(feature = "std")]
+        got: String,
+    },
+}
+
+impl ParseError {
+    /// An invalid hex flag was encountered.
+    pub fn invalid_hex_flag(flag: impl fmt::Display) -> Self {
+        let _flag = flag;
+
+        let got = {
+            #[cfg(feature = "std")]
+            {
+                _flag.to_string()
+            }
+        };
+
+        ParseError(ParseErrorKind::InvalidHexFlag { got })
+    }
+
+    /// A named flag that doesn't correspond to any on the flags type was encountered.
+    pub fn invalid_named_flag(flag: impl fmt::Display) -> Self {
+        let _flag = flag;
+
+        let got = {
+            #[cfg(feature = "std")]
+            {
+                _flag.to_string()
+            }
+        };
+
+        ParseError(ParseErrorKind::InvalidNamedFlag { got })
+    }
+
+    /// A hex or named flag wasn't found between separators.
+    pub const fn empty_flag() -> Self {
+        ParseError(ParseErrorKind::EmptyFlag)
+    }
+}
+
+impl fmt::Display for ParseError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match &self.0 {
+            ParseErrorKind::InvalidNamedFlag { got } => {
+                let _got = got;
+
+                write!(f, "unrecognized named flag")?;
+
+                #[cfg(feature = "std")]
+                {
+                    write!(f, " `{}`", _got)?;
+                }
+            }
+            ParseErrorKind::InvalidHexFlag { got } => {
+                let _got = got;
+
+                write!(f, "invalid hex flag")?;
+
+                #[cfg(feature = "std")]
+                {
+                    write!(f, " `{}`", _got)?;
+                }
+            }
+            ParseErrorKind::EmptyFlag => {
+                write!(f, "encountered empty flag")?;
+            }
+        }
+
+        Ok(())
+    }
+}
+
+#[cfg(feature = "std")]
+impl std::error::Error for ParseError {}