Refactor buffer reader

src/lib.rs

@@ -5,6 +5,7 @@
 
 pub mod packet;
 pub mod encoding;
+pub mod utils;
 
 #[allow(unused_variables)]
 pub fn print_stack(file: &'static str, line: u32) {

src/packet/property.rs

@@ -1,4 +1,9 @@
-use crate::encoding::variable_byte_integer::VariableByteIntegerDecoder;
+use crate::utils::buffer_reader::ProperyParseError;
+use crate::utils::buffer_reader::StringPair;
+use crate::utils::buffer_reader::EncodedString;
+use crate::utils::buffer_reader::BinaryData;
+use crate::encoding::variable_byte_integer::VariableByteIntegerError;
+/*use crate::encoding::variable_byte_integer::VariableByteIntegerDecoder;
 use crate::encoding::variable_byte_integer::VariableByteIntegerError;
 use core::str;
 
@@ -6,30 +11,7 @@ use core::str;
 pub trait Decode<'a> {
     fn decode(input: &'a [u8], offset: &'a mut usize) -> Result<Self, ProperyParseError> where Self: Sized;
 }
-
-pub struct EncodedString<'a> {
-    pub string: &'a str,
-    pub len: u16
-}
-
-pub struct BinaryData<'a> {
-    pub bin: &'a [u8],
-    pub len: u16
-}
-
-pub struct StringPair<'a> {
-    pub name: EncodedString<'a>,
-    pub value: EncodedString<'a>
-}
-
-#[derive(core::fmt::Debug)]
-pub enum ProperyParseError {
-    Utf8Error,
-    IndexOutOfBounce,
-    VariableByteIntegerError,
-    IdNotFound
-}
-
+*/
 pub enum Property<'a> {
     PayloadFormat(Result<u8, ProperyParseError>),
     MessageExpiryInterval(Result<u32, ProperyParseError>),
@@ -60,7 +42,7 @@ pub enum Property<'a> {
     SharedSubscriptionAvailable(Result<u8, ProperyParseError>)
 }
 
-
+/*
 impl<'a> Decode<'a> for Property<'a> {
     fn decode(input: &'a [u8], offset: &'a mut usize) -> Result<Self, ProperyParseError> {
         let propertyIdentifier = parseU8(input, offset); 
@@ -95,88 +77,5 @@ impl<'a> Decode<'a> for Property<'a> {
             _ => return Err(ProperyParseError::IdNotFound)
         }
     }
-}
+}*/
 
-fn parseVariableByteInt<'a>(input: &'a [u8], offset: & mut usize) -> Result<u32, VariableByteIntegerError> { 
-    let variable_byte_integer: [u8; 4] = [input[*offset], input[*offset + 1], input[*offset + 2], input[*offset + 3]];
-    *offset = *offset + 4;
-    return VariableByteIntegerDecoder::decode(variable_byte_integer);
-}
-
-fn parseU32<'a>(input: &'a [u8], offset: & mut usize) -> Result<u32, ProperyParseError> {
-    let ret: u32 = (((input[*offset] as u32) << 24) | ((input[*offset + 1] as u32) << 16) | ((input[*offset + 2] as u32) << 8) | (input[*offset + 3] as u32)) as u32;
-    *offset = *offset + 4;
-    return Ok(ret);
-}
-
-fn parseU16<'a>(input: &'a [u8], offset: & mut usize) -> Result<u16, ProperyParseError> {
-    let ret: u16 = (((input[*offset] as u16) << 8) | (input[*offset + 1] as u16)) as u16;
-    *offset = *offset + 2;
-    return Ok(ret);
-}
-
-fn parseU8<'a>(input: &'a [u8], offset: & mut usize) -> Result<u8, ProperyParseError> {
-    let ret: u8 = input[*offset];
-    *offset = *offset + 1;
-    return Ok(ret);
-}
-
-fn parseString<'a>(input: &'a [u8], offset: & mut usize) -> Result<EncodedString<'a>, ProperyParseError> {
-    let len = parseU16(input, offset);
-    match len {
-        Err(err) => return Err(err),
-        _ => log::debug!("[parseString] let not parsed")
-    }
-    let len_res = len.unwrap();
-    let res_str = str::from_utf8(&(input[*offset..(*offset + len_res as usize)]));
-    if res_str.is_err() {
-        log::error!("Could not parse utf-8 string");
-        return Err(ProperyParseError::Utf8Error);
-    }
-    return Ok(EncodedString { string: res_str.unwrap(), len: len_res });
-}
-
-//TODO: Index out of bounce err !!!!!
-fn parseBinary<'a>(input: &'a [u8], offset: & mut usize) -> Result<BinaryData<'a>, ProperyParseError> {
-    let len = parseU16(input, offset);
-    match len {
-        Err(err) => return Err(err),
-        _ => log::debug!("[parseBinary] let not parsed")
-    }
-    let len_res = len.unwrap();
-    let res_bin = &(input[*offset..(*offset + len_res as usize)]);
-    return Ok(BinaryData { bin: res_bin, len: len_res });
-}
-
-fn parseStringPair<'a>(input: &'a [u8], offset: & mut usize) -> Result<StringPair<'a>, ProperyParseError> {
-    let name = parseString(input, offset);
-    match name {
-        Err(err) => return Err(err),
-        _ => log::debug!("[String pair] name not parsed")
-    }
-    let value = parseString(input, offset);
-    match value {
-        Err(err) => return Err(err),
-        _ => log::debug!("[String pair] value not parsed")
-    }
-    return Ok(StringPair { name: name.unwrap(), value: value.unwrap() });
-}
-
-/*impl<'a> From<u8> for Property<'a> {
-    fn from(orig: u8) -> Self {
-        match orig {
-            0x01 => return Property::PayloadFormat,
-            0x02 => return Property::MessageExpiryInterval,
-            0x03 => return Property::ContentType,
-            0x08 => return Property::ResponseTopic,
-            0x09 => return Property::CorrelationData,
-            0x0B => return Property::SubscriptionIdentifier,
-            0x11 => return Property::SessionExpiryInterval,
-            0x12 => return Property::AssignedClientIdentifier,
-            0x13 => return Property::ServerKeepAlive,
-            0x15 => return Property::AuthenticationMethod,
-            0x16 => return Property::AuthenticationMethod
-            _ => return Property::TopicAlias
-        }
-    }
-}*/

src/utils/buffer_reader.rs

@@ -0,0 +1,111 @@
+use crate::encoding::variable_byte_integer::VariableByteIntegerDecoder;
+use crate::encoding::variable_byte_integer::VariableByteIntegerError;
+use core::str;
+use core::mem;
+
+pub struct EncodedString<'a> {
+    pub string: &'a str,
+    pub len: u16
+}
+
+pub struct BinaryData<'a> {
+    pub bin: &'a [u8],
+    pub len: u16
+}
+
+pub struct StringPair<'a> {
+    pub name: EncodedString<'a>,
+    pub value: EncodedString<'a>
+}
+
+#[derive(core::fmt::Debug)]
+pub enum ProperyParseError {
+    Utf8Error,
+    IndexOutOfBounce,
+    VariableByteIntegerError,
+    IdNotFound
+}
+
+pub struct BuffReader<'a> {
+    buffer: &'a [u8],
+    pub position: usize,
+}
+
+impl<'a> BuffReader<'a> {
+    pub fn incrementPosition(& mut self, increment: usize) {
+        self.position = self.position + increment;
+    }
+
+    pub fn new(buffer: &'a [u8]) -> Self {
+        return BuffReader { buffer: buffer, position: 0 };
+    }
+
+    pub fn readVariableByteInt(& mut self) -> Result<u32, VariableByteIntegerError> { 
+        let variable_byte_integer: [u8; 4] = [self.buffer[self.position], self.buffer[self.position + 1], self.buffer[self.position + 2], self.buffer[self.position + 3]];
+        self.incrementPosition(4);
+        return VariableByteIntegerDecoder::decode(variable_byte_integer);
+    }
+    
+    pub fn readU32(& mut self) -> Result<u32, ProperyParseError> {
+        let (int_bytes, rest) = self.buffer.split_at(mem::size_of::<u32>());
+        let ret: u32 = u32::from_le_bytes(int_bytes.try_into().unwrap());
+        //let ret: u32 = (((self.buffer[self.position] as u32) << 24) | ((self.buffer[self.position + 1] as u32) << 16) | ((self.buffer[self.position + 2] as u32) << 8) | (self.buffer[self.position + 3] as u32)) as u32;
+        self.incrementPosition(4);
+        return Ok(ret);
+    }
+    
+    pub fn readU16(& mut self) -> Result<u16, ProperyParseError> {
+        let (int_bytes, rest) = self.buffer.split_at(mem::size_of::<u16>());
+        let ret: u16 =  u16::from_le_bytes(int_bytes.try_into().unwrap());
+        //(((self.buffer[self.position] as u16) << 8) | (self.buffer[self.position + 1] as u16)) as u16;
+        self.incrementPosition(2);
+        return Ok(ret);
+    }
+    
+    pub fn readU8(& mut self) -> Result<u8, ProperyParseError> {
+        let ret: u8 = self.buffer[self.position];
+        self.incrementPosition(1);
+        return Ok(ret);
+    }
+    
+    pub fn readString(& mut self) -> Result<EncodedString<'a>, ProperyParseError> {
+        let len = self.readU16();
+        match len {
+            Err(err) => return Err(err),
+            _ => log::debug!("[parseString] let not parsed")
+        }
+        let len_res = len.unwrap();
+        let res_str = str::from_utf8(&(self.buffer[self.position..(self.position + len_res as usize)]));
+        if res_str.is_err() {
+            log::error!("Could not parse utf-8 string");
+            return Err(ProperyParseError::Utf8Error);
+        }
+        return Ok(EncodedString { string: res_str.unwrap(), len: len_res });
+    }
+    
+    //TODO: Index out of bounce err !!!!!
+    pub fn readBinary(& mut self) -> Result<BinaryData<'a>, ProperyParseError> {
+        let len = self.readU16();
+        match len {
+            Err(err) => return Err(err),
+            _ => log::debug!("[parseBinary] let not parsed")
+        }
+        let len_res = len.unwrap();
+        let res_bin = &(self.buffer[self.position..(self.position + len_res as usize)]);
+        return Ok(BinaryData { bin: res_bin, len: len_res });
+    }
+    
+    pub fn readStringPair(& mut self) -> Result<StringPair<'a>, ProperyParseError> {
+        let name = self.readString();
+        match name {
+            Err(err) => return Err(err),
+            _ => log::debug!("[String pair] name not parsed")
+        }
+        let value = self.readString();
+        match value {
+            Err(err) => return Err(err),
+            _ => log::debug!("[String pair] value not parsed")
+        }
+        return Ok(StringPair { name: name.unwrap(), value: value.unwrap() });
+    }
+}

src/utils/mod.rs

@@ -0,0 +1 @@
+pub mod buffer_reader;