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Diffstat (limited to 'utf8parse/src/types.rs')
-rw-r--r-- | utf8parse/src/types.rs | 100 |
1 files changed, 0 insertions, 100 deletions
diff --git a/utf8parse/src/types.rs b/utf8parse/src/types.rs deleted file mode 100644 index 8a52c67..0000000 --- a/utf8parse/src/types.rs +++ /dev/null @@ -1,100 +0,0 @@ -//! Types supporting the UTF-8 parser - -/// Action to take when receiving a byte -#[derive(Debug, Copy, Clone)] -pub enum Action { - /// Unexpected byte; sequence is invalid - InvalidSequence = 0, - /// Received valid 7-bit ASCII byte which can be directly emitted. - EmitByte = 1, - /// Set the bottom continuation byte - SetByte1 = 2, - /// Set the 2nd-from-last continuation byte - SetByte2 = 3, - /// Set the 2nd-from-last byte which is part of a two byte sequence - SetByte2Top = 4, - /// Set the 3rd-from-last continuation byte - SetByte3 = 5, - /// Set the 3rd-from-last byte which is part of a three byte sequence - SetByte3Top = 6, - /// Set the top byte of a four byte sequence. - SetByte4 = 7, -} - -/// States the parser can be in. -/// -/// There is a state for each initial input of the 3 and 4 byte sequences since -/// the following bytes are subject to different conditions than a tail byte. -#[allow(non_camel_case_types)] -#[derive(Debug, Default, Copy, Clone, PartialEq, Eq)] -pub enum State { - /// Ground state; expect anything - #[default] - Ground = 0, - /// 3 tail bytes - Tail3 = 1, - /// 2 tail bytes - Tail2 = 2, - /// 1 tail byte - Tail1 = 3, - /// UTF8-3 starting with E0 - U3_2_e0 = 4, - /// UTF8-3 starting with ED - U3_2_ed = 5, - /// UTF8-4 starting with F0 - Utf8_4_3_f0 = 6, - /// UTF8-4 starting with F4 - Utf8_4_3_f4 = 7, -} - -impl State { - /// Advance the parser state. - /// - /// This takes the current state and input byte into consideration, to determine the next state - /// and any action that should be taken. - #[inline] - pub fn advance(self, byte: u8) -> (State, Action) { - match self { - State::Ground => match byte { - 0x00..=0x7f => (State::Ground, Action::EmitByte), - 0xc2..=0xdf => (State::Tail1, Action::SetByte2Top), - 0xe0 => (State::U3_2_e0, Action::SetByte3Top), - 0xe1..=0xec => (State::Tail2, Action::SetByte3Top), - 0xed => (State::U3_2_ed, Action::SetByte3Top), - 0xee..=0xef => (State::Tail2, Action::SetByte3Top), - 0xf0 => (State::Utf8_4_3_f0, Action::SetByte4), - 0xf1..=0xf3 => (State::Tail3, Action::SetByte4), - 0xf4 => (State::Utf8_4_3_f4, Action::SetByte4), - _ => (State::Ground, Action::InvalidSequence), - }, - State::U3_2_e0 => match byte { - 0xa0..=0xbf => (State::Tail1, Action::SetByte2), - _ => (State::Ground, Action::InvalidSequence), - }, - State::U3_2_ed => match byte { - 0x80..=0x9f => (State::Tail1, Action::SetByte2), - _ => (State::Ground, Action::InvalidSequence), - }, - State::Utf8_4_3_f0 => match byte { - 0x90..=0xbf => (State::Tail2, Action::SetByte3), - _ => (State::Ground, Action::InvalidSequence), - }, - State::Utf8_4_3_f4 => match byte { - 0x80..=0x8f => (State::Tail2, Action::SetByte3), - _ => (State::Ground, Action::InvalidSequence), - }, - State::Tail3 => match byte { - 0x80..=0xbf => (State::Tail2, Action::SetByte3), - _ => (State::Ground, Action::InvalidSequence), - }, - State::Tail2 => match byte { - 0x80..=0xbf => (State::Tail1, Action::SetByte2), - _ => (State::Ground, Action::InvalidSequence), - }, - State::Tail1 => match byte { - 0x80..=0xbf => (State::Ground, Action::SetByte1), - _ => (State::Ground, Action::InvalidSequence), - }, - } - } -} |