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Diffstat (limited to 'third_party/rust/rkv/src/value.rs')
| -rw-r--r-- | third_party/rust/rkv/src/value.rs | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/third_party/rust/rkv/src/value.rs b/third_party/rust/rkv/src/value.rs new file mode 100644 index 0000000000..762607acd3 --- /dev/null +++ b/third_party/rust/rkv/src/value.rs @@ -0,0 +1,252 @@ +// Copyright 2018-2019 Mozilla +// +// Licensed under the Apache License, Version 2.0 (the "License"); you may not use +// this file except in compliance with the License. You may obtain a copy of the +// License at http://www.apache.org/licenses/LICENSE-2.0 +// Unless required by applicable law or agreed to in writing, software distributed +// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR +// CONDITIONS OF ANY KIND, either express or implied. See the License for the +// specific language governing permissions and limitations under the License. + +use std::fmt; + +use arrayref::array_ref; +use bincode::{deserialize, serialize, serialized_size}; +use ordered_float::OrderedFloat; +use uuid::{Bytes, Uuid}; + +use crate::error::DataError; + +/// We define a set of types, associated with simple integers, to annotate values stored +/// in LMDB. This is to avoid an accidental 'cast' from a value of one type to another. +/// For this reason we don't simply use `deserialize` from the `bincode` crate. +#[repr(u8)] +#[derive(Debug, PartialEq, Eq)] +pub enum Type { + Bool = 1, + U64 = 2, + I64 = 3, + F64 = 4, + Instant = 5, // Millisecond-precision timestamp. + Uuid = 6, + Str = 7, + Json = 8, + Blob = 9, +} + +/// We use manual tagging, because <https://github.com/serde-rs/serde/issues/610>. +impl Type { + pub fn from_tag(tag: u8) -> Result<Type, DataError> { + #![allow(clippy::unnecessary_lazy_evaluations)] + Type::from_primitive(tag).ok_or_else(|| DataError::UnknownType(tag)) + } + + #[allow(clippy::wrong_self_convention)] + pub fn to_tag(self) -> u8 { + self as u8 + } + + fn from_primitive(p: u8) -> Option<Type> { + match p { + 1 => Some(Type::Bool), + 2 => Some(Type::U64), + 3 => Some(Type::I64), + 4 => Some(Type::F64), + 5 => Some(Type::Instant), + 6 => Some(Type::Uuid), + 7 => Some(Type::Str), + 8 => Some(Type::Json), + 9 => Some(Type::Blob), + _ => None, + } + } +} + +impl fmt::Display for Type { + fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> { + f.write_str(match *self { + Type::Bool => "bool", + Type::U64 => "u64", + Type::I64 => "i64", + Type::F64 => "f64", + Type::Instant => "instant", + Type::Uuid => "uuid", + Type::Str => "str", + Type::Json => "json", + Type::Blob => "blob", + }) + } +} + +#[derive(Debug, Eq, PartialEq)] +pub enum Value<'v> { + Bool(bool), + U64(u64), + I64(i64), + F64(OrderedFloat<f64>), + Instant(i64), // Millisecond-precision timestamp. + Uuid(&'v Bytes), + Str(&'v str), + Json(&'v str), + Blob(&'v [u8]), +} + +#[derive(Clone, Debug, PartialEq)] +pub enum OwnedValue { + Bool(bool), + U64(u64), + I64(i64), + F64(f64), + Instant(i64), // Millisecond-precision timestamp. + Uuid(Uuid), + Str(String), + Json(String), // TODO + Blob(Vec<u8>), +} + +fn uuid(bytes: &[u8]) -> Result<Value, DataError> { + if bytes.len() == 16 { + Ok(Value::Uuid(array_ref![bytes, 0, 16])) + } else { + Err(DataError::InvalidUuid) + } +} + +impl<'v> Value<'v> { + pub fn from_tagged_slice(slice: &'v [u8]) -> Result<Value<'v>, DataError> { + let (tag, data) = slice.split_first().ok_or(DataError::Empty)?; + let t = Type::from_tag(*tag)?; + Value::from_type_and_data(t, data) + } + + fn from_type_and_data(t: Type, data: &'v [u8]) -> Result<Value<'v>, DataError> { + if t == Type::Uuid { + return deserialize(data) + .map_err(|e| DataError::DecodingError { + value_type: t, + err: e, + }) + .map(uuid)?; + } + + match t { + Type::Bool => deserialize(data).map(Value::Bool), + Type::U64 => deserialize(data).map(Value::U64), + Type::I64 => deserialize(data).map(Value::I64), + Type::F64 => deserialize(data).map(OrderedFloat).map(Value::F64), + Type::Instant => deserialize(data).map(Value::Instant), + Type::Str => deserialize(data).map(Value::Str), + Type::Json => deserialize(data).map(Value::Json), + Type::Blob => deserialize(data).map(Value::Blob), + Type::Uuid => { + // Processed above to avoid verbose duplication of error transforms. + unreachable!() + } + } + .map_err(|e| DataError::DecodingError { + value_type: t, + err: e, + }) + } + + pub fn to_bytes(&self) -> Result<Vec<u8>, DataError> { + match self { + Value::Bool(v) => serialize(&(Type::Bool.to_tag(), *v)), + Value::U64(v) => serialize(&(Type::U64.to_tag(), *v)), + Value::I64(v) => serialize(&(Type::I64.to_tag(), *v)), + Value::F64(v) => serialize(&(Type::F64.to_tag(), v.0)), + Value::Instant(v) => serialize(&(Type::Instant.to_tag(), *v)), + Value::Str(v) => serialize(&(Type::Str.to_tag(), v)), + Value::Json(v) => serialize(&(Type::Json.to_tag(), v)), + Value::Blob(v) => serialize(&(Type::Blob.to_tag(), v)), + Value::Uuid(v) => serialize(&(Type::Uuid.to_tag(), v)), + } + .map_err(DataError::EncodingError) + } + + pub fn serialized_size(&self) -> Result<u64, DataError> { + match self { + Value::Bool(v) => serialized_size(&(Type::Bool.to_tag(), *v)), + Value::U64(v) => serialized_size(&(Type::U64.to_tag(), *v)), + Value::I64(v) => serialized_size(&(Type::I64.to_tag(), *v)), + Value::F64(v) => serialized_size(&(Type::F64.to_tag(), v.0)), + Value::Instant(v) => serialized_size(&(Type::Instant.to_tag(), *v)), + Value::Str(v) => serialized_size(&(Type::Str.to_tag(), v)), + Value::Json(v) => serialized_size(&(Type::Json.to_tag(), v)), + Value::Blob(v) => serialized_size(&(Type::Blob.to_tag(), v)), + Value::Uuid(v) => serialized_size(&(Type::Uuid.to_tag(), v)), + } + .map_err(DataError::EncodingError) + } +} + +impl<'v> From<&'v Value<'v>> for OwnedValue { + fn from(value: &Value) -> OwnedValue { + match value { + Value::Bool(v) => OwnedValue::Bool(*v), + Value::U64(v) => OwnedValue::U64(*v), + Value::I64(v) => OwnedValue::I64(*v), + Value::F64(v) => OwnedValue::F64(**v), + Value::Instant(v) => OwnedValue::Instant(*v), + Value::Uuid(v) => OwnedValue::Uuid(Uuid::from_bytes(**v)), + Value::Str(v) => OwnedValue::Str((*v).to_string()), + Value::Json(v) => OwnedValue::Json((*v).to_string()), + Value::Blob(v) => OwnedValue::Blob(v.to_vec()), + } + } +} + +impl<'v> From<&'v OwnedValue> for Value<'v> { + fn from(value: &OwnedValue) -> Value { + match value { + OwnedValue::Bool(v) => Value::Bool(*v), + OwnedValue::U64(v) => Value::U64(*v), + OwnedValue::I64(v) => Value::I64(*v), + OwnedValue::F64(v) => Value::F64(OrderedFloat::from(*v)), + OwnedValue::Instant(v) => Value::Instant(*v), + OwnedValue::Uuid(v) => Value::Uuid(v.as_bytes()), + OwnedValue::Str(v) => Value::Str(v), + OwnedValue::Json(v) => Value::Json(v), + OwnedValue::Blob(v) => Value::Blob(v), + } + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn test_value_serialized_size() { + // | Value enum | tag: 1 byte | value_payload | + // |----------------------------------------------------------| + // | I64 | 1 | 8 | + // | U64 | 1 | 8 | + // | Bool | 1 | 1 | + // | Instant | 1 | 8 | + // | F64 | 1 | 8 | + // | Uuid | 1 | 16 | + // | Str/Blob/Json | 1 |(8: len + sizeof(payload))| + assert_eq!(Value::I64(-1000).serialized_size().unwrap(), 9); + assert_eq!(Value::U64(1000u64).serialized_size().unwrap(), 9); + assert_eq!(Value::Bool(true).serialized_size().unwrap(), 2); + assert_eq!( + Value::Instant(1_558_020_865_224).serialized_size().unwrap(), + 9 + ); + assert_eq!( + Value::F64(OrderedFloat(10000.1)).serialized_size().unwrap(), + 9 + ); + assert_eq!(Value::Str("hello!").serialized_size().unwrap(), 15); + assert_eq!(Value::Str("¡Hola").serialized_size().unwrap(), 15); + assert_eq!(Value::Blob(b"hello!").serialized_size().unwrap(), 15); + assert_eq!( + uuid(b"\x9f\xe2\xc4\xe9\x3f\x65\x4f\xdb\xb2\x4c\x02\xb1\x52\x59\x71\x6c") + .unwrap() + .serialized_size() + .unwrap(), + 17 + ); + } +} |