From a63f31a0f7955ffd218c3b6e49ffdc69152d4691 Mon Sep 17 00:00:00 2001
From: NikVolf <nikvolf@gmail.com>
Date: Mon, 3 Apr 2017 17:31:51 +0300
Subject: [PATCH] opcodes stub & data segment

---
 src/elements/ops.rs        | 61 +++++++++++++++++++++++++++++++++++++-
 src/elements/primitives.rs | 18 +++++++++++
 src/elements/segment.rs    |  3 ++
 src/elements/types.rs      | 18 ++++++++++-
 4 files changed, 98 insertions(+), 2 deletions(-)

diff --git a/src/elements/ops.rs b/src/elements/ops.rs
index 8c05fd3..d6b0a90 100644
--- a/src/elements/ops.rs
+++ b/src/elements/ops.rs
@@ -1,5 +1,6 @@
 use std::io;
-use super::{Deserialize, Error, VarUint7, 
+use super::{
+    Serialize, Deserialize, Error, VarUint7, 
     VarUint1, VarUint32, CountedList, BlockType,
     Uint32, VarUint64, Uint64
 };
@@ -527,3 +528,61 @@ impl Deserialize for Opcode {
         )
     }
 }
+
+macro_rules! op {
+    ($writer: expr, $byte: expr) => ({
+        let b: u8 = $byte;
+        $writer.write_all(&[b])?;
+    });
+    ($writer: expr, $byte: expr, $s: block) => ({
+        op!($writer, $byte);
+        $s;
+    });
+}
+
+impl Serialize for Opcode {
+    type Error = Error;
+    
+    fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
+        use self::Opcode::*;
+
+        match self {
+            Unreachable => op!(writer, 0x00),
+            Nop => op!(writer, 0x01),
+            Block(block_type, ops) => op!(writer, 0x02, {
+               block_type.serialize(writer)?;
+               ops.serialize(writer)?;
+            }),            
+            End => op!(writer, 0x0b),           
+            _ => unreachable!(),
+        }
+
+        Ok(())
+    }
+    
+}
+
+impl Serialize for Opcodes {
+    type Error = Error;
+    
+    fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
+        for op in self.0.into_iter() {
+            op.serialize(writer)?;
+        }
+
+        Ok(())
+    }
+}
+
+impl Serialize for InitExpr {
+    type Error = Error;
+    
+    fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
+        for op in self.0.into_iter() {
+            op.serialize(writer)?;
+        }
+
+        Ok(())
+    }
+}
+
diff --git a/src/elements/primitives.rs b/src/elements/primitives.rs
index 7a5fc11..020d210 100644
--- a/src/elements/primitives.rs
+++ b/src/elements/primitives.rs
@@ -125,6 +125,12 @@ impl From<VarInt7> for i8 {
     }
 }
 
+impl From<i8> for VarInt7 {
+    fn from(v: i8) -> VarInt7 {
+        VarInt7(v)
+    }
+}
+
 impl Deserialize for VarInt7 {
     type Error = Error;
 
@@ -138,6 +144,18 @@ impl Deserialize for VarInt7 {
     }
 }
 
+impl Serialize for VarInt7 {
+    type Error = Error;
+
+    fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
+        // todo check range?
+        let mut b: u8 = self.0 as u8;
+        if self.0 < 0 { b |= 0b0100_0000 }
+        writer.write_all(&[b])?;
+        Ok(())
+    }
+}
+
 #[derive(Copy, Clone)]
 pub struct Uint32(u32);
 
diff --git a/src/elements/segment.rs b/src/elements/segment.rs
index 3cd3b79..164cbb2 100644
--- a/src/elements/segment.rs
+++ b/src/elements/segment.rs
@@ -68,6 +68,9 @@ impl Serialize for DataSegment {
     type Error = Error;
     
     fn serialize<W: io::Write>(self, writer: &mut W) -> Result<(), Self::Error> {
+        VarUint32::from(self.index).serialize(writer)?;
+        self.offset.serialize(writer)?;
+        writer.write_all(&self.value[..])?;
         Ok(())
     }
 }
\ No newline at end of file
diff --git a/src/elements/types.rs b/src/elements/types.rs
index 8eeadc5..7422f7e 100644
--- a/src/elements/types.rs
+++ b/src/elements/types.rs
@@ -1,5 +1,5 @@
 use std::io;
-use super::{Deserialize, Error, VarUint7, VarInt7, VarUint1, CountedList};
+use super::{Deserialize, Serialize, Error, VarUint7, VarInt7, VarUint1, CountedList};
 
 pub enum Type {
     Function(FunctionType),
@@ -60,6 +60,22 @@ impl Deserialize for BlockType {
     }    
 }
 
+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,
+        }.into();
+        val.serialize(writer)?;
+        Ok(())
+    }
+}
+
 
 pub struct FunctionType {
     form: u8,