1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
use crate::rust::{fmt, vec::Vec};
use crate::io;
use super::{
	Deserialize, Serialize, Error, VarUint7, VarInt7, VarUint1, CountedList,
	CountedListWriter, VarUint32,
};

/// Type definition in types section. Currently can be only of the function type.
#[derive(Debug, Clone, PartialEq, Hash, Eq)]
pub enum Type {
	/// Function type.
	Function(FunctionType),
}

impl Deserialize for Type {
	type Error = Error;

	fn deserialize<R: io::Read>(reader: &mut R) -> Result<Self, Self::Error> {
		Ok(Type::Function(FunctionType::deserialize(reader)?))
	}
}

impl Serialize for Type {
	type Error = Error;

	fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
		match self {
			Type::Function(fn_type) => fn_type.serialize(writer)
		}
	}
}

/// Value type.
#[derive(Clone, Copy, Debug, PartialEq, Hash, Eq)]
pub enum ValueType {
	/// 32-bit signed integer
	I32,
	/// 64-bit signed integer
	I64,
	/// 32-bit float
	F32,
	/// 64-bit float
	F64,
	/// 128-bit SIMD register
	V128,
}

impl Deserialize for ValueType {
	type Error = Error;

	fn deserialize<R: io::Read>(reader: &mut R) -> Result<Self, Self::Error> {
		let val = VarInt7::deserialize(reader)?;

		match val.into() {
			-0x01 => Ok(ValueType::I32),
			-0x02 => Ok(ValueType::I64),
			-0x03 => Ok(ValueType::F32),
			-0x04 => Ok(ValueType::F64),
			-0x05 => Ok(ValueType::V128),
			_ => Err(Error::UnknownValueType(val.into())),
		}
	}
}

impl Serialize for ValueType {
	type Error = Error;

	fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
		let val: VarInt7 = match self {
			ValueType::I32 => -0x01,
			ValueType::I64 => -0x02,
			ValueType::F32 => -0x03,
			ValueType::F64 => -0x04,
			ValueType::V128 => -0x05,
		}.into();
		val.serialize(writer)?;
		Ok(())
	}
}

impl fmt::Display for ValueType {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		match *self {
			ValueType::I32 => write!(f, "i32"),
			ValueType::I64 => write!(f, "i64"),
			ValueType::F32 => write!(f, "f32"),
			ValueType::F64 => write!(f, "f64"),
			ValueType::V128 => write!(f, "v128"),
		}
	}
}

/// Block type which is basically `ValueType` + NoResult (to define blocks that have no return type)
#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
pub enum BlockType {
	/// Value-type specified block type
	Value(ValueType),
	/// No specified block type
	NoResult,
}

impl Deserialize for BlockType {
	type Error = Error;

	fn deserialize<R: io::Read>(reader: &mut R) -> Result<Self, Self::Error> {
		let val = VarInt7::deserialize(reader)?;

		match val.into() {
			-0x01 => Ok(BlockType::Value(ValueType::I32)),
			-0x02 => Ok(BlockType::Value(ValueType::I64)),
			-0x03 => Ok(BlockType::Value(ValueType::F32)),
			-0x04 => Ok(BlockType::Value(ValueType::F64)),
			0x7b => Ok(BlockType::Value(ValueType::V128)),
			-0x40 => Ok(BlockType::NoResult),
			_ => Err(Error::UnknownValueType(val.into())),
		}
	}
}

impl Serialize for BlockType {
	type Error = Error;

	fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
		let val: VarInt7 = match self {
			BlockType::NoResult => -0x40i8,
			BlockType::Value(ValueType::I32) => -0x01,
			BlockType::Value(ValueType::I64) => -0x02,
			BlockType::Value(ValueType::F32) => -0x03,
			BlockType::Value(ValueType::F64) => -0x04,
			BlockType::Value(ValueType::V128) => 0x7b,
		}.into();
		val.serialize(writer)?;
		Ok(())
	}
}

/// Function signature type.
#[derive(Debug, Clone, PartialEq, Hash, Eq)]
pub struct FunctionType {
	form: u8,
	params: Vec<ValueType>,
	return_type: Option<ValueType>,
}

impl Default for FunctionType {
	fn default() -> Self {
		FunctionType {
			form: 0x60,
			params: Vec::new(),
			return_type: None,
		}
	}
}

impl FunctionType {
	/// New function type given the signature in-params(`params`) and return type (`return_type`)
	pub fn new(params: Vec<ValueType>, return_type: Option<ValueType>) -> Self {
		FunctionType {
			params: params,
			return_type: return_type,
			..Default::default()
		}
	}
	/// Function form (currently only valid value is `0x60`)
	pub fn form(&self) -> u8 { self.form }
	/// Parameters in the function signature.
	pub fn params(&self) -> &[ValueType] { &self.params }
	/// Mutable parameters in the function signature.
	pub fn params_mut(&mut self) -> &mut Vec<ValueType> { &mut self.params }
	/// Return type in the function signature, if any.
	pub fn return_type(&self) -> Option<ValueType> { self.return_type }
	/// Mutable type in the function signature, if any.
	pub fn return_type_mut(&mut self) -> &mut Option<ValueType> { &mut self.return_type }
}

impl Deserialize for FunctionType {
	type Error = Error;

	fn deserialize<R: io::Read>(reader: &mut R) -> Result<Self, Self::Error> {
		let form: u8 = VarUint7::deserialize(reader)?.into();

		if form != 0x60 {
			return Err(Error::UnknownFunctionForm(form));
		}

		let params: Vec<ValueType> = CountedList::deserialize(reader)?.into_inner();

		let return_types: u32 = VarUint32::deserialize(reader)?.into();

		let return_type = if return_types == 1 {
			Some(ValueType::deserialize(reader)?)
		} else if return_types == 0 {
			None
		} else {
			return Err(Error::Other("Return types length should be 0 or 1"));
		};

		Ok(FunctionType {
			form: form,
			params: params,
			return_type: return_type,
		})
	}
}

impl Serialize for FunctionType {
	type Error = Error;

	fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
		VarUint7::from(self.form).serialize(writer)?;

		let data = self.params;
		let counted_list = CountedListWriter::<ValueType, _>(
			data.len(),
			data.into_iter().map(Into::into),
		);
		counted_list.serialize(writer)?;

		if let Some(return_type) = self.return_type {
			VarUint1::from(true).serialize(writer)?;
			return_type.serialize(writer)?;
		} else {
			VarUint1::from(false).serialize(writer)?;
		}

		Ok(())
	}
}

/// Table element type.
#[derive(Clone, Copy, Debug, PartialEq)]
pub enum TableElementType {
	/// A reference to a function with any signature.
	AnyFunc,
}

impl Deserialize for TableElementType {
	type Error = Error;

	fn deserialize<R: io::Read>(reader: &mut R) -> Result<Self, Self::Error> {
		let val = VarInt7::deserialize(reader)?;

		match val.into() {
			-0x10 => Ok(TableElementType::AnyFunc),
			_ => Err(Error::UnknownTableElementType(val.into())),
		}
	}
}

impl Serialize for TableElementType {
	type Error = Error;

	fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
		let val: VarInt7 = match self {
			TableElementType::AnyFunc => -0x10,
		}.into();
		val.serialize(writer)?;
		Ok(())
	}
}