Avoid custom non-zigzag read/write functions
diff --git a/lib/rs/src/protocol/compact.rs b/lib/rs/src/protocol/compact.rs
index 3687354..f885e40 100644
--- a/lib/rs/src/protocol/compact.rs
+++ b/lib/rs/src/protocol/compact.rs
@@ -80,24 +80,6 @@
}
}
- /// Reads a varint for an `i32` without attempting to zigzag-decode it.
- fn read_non_zigzag_varint(&mut self) -> crate::Result<i32> {
- let mut num = 0i32;
-
- let mut buf = [0u8; 1];
- let mut shift_bits = 0u32;
- let mut should_continue = true;
-
- while should_continue {
- self.transport.read_exact(&mut buf)?;
- num |= ((buf[0] & 0x7F) as i32) << shift_bits;
- shift_bits += 7;
- should_continue = (buf[0] & 0x80) > 0;
- }
-
- Ok(num)
- }
-
fn read_list_set_begin(&mut self) -> crate::Result<(TType, i32)> {
let header = self.read_byte()?;
let element_type = collection_u8_to_type(header & 0x0F)?;
@@ -146,7 +128,8 @@
// NOTE: unsigned right shift will pad with 0s
let message_type: TMessageType = TMessageType::try_from(type_and_byte >> 5)?;
- let sequence_number = self.read_non_zigzag_varint()?;
+ // writing side wrote signed sequence number as u32 to avoid zigzag encoding
+ let sequence_number = self.transport.read_varint::<u32>()? as i32;
let service_call_name = self.read_string()?;
self.last_read_field_id = 0;
@@ -395,27 +378,6 @@
}
}
- /// Writes a varint for an `i32` without attempting to zigzag-encode it first.
- fn write_non_zigzag_varint(&mut self, i: i32) -> crate::Result<()> {
- let mut output = Vec::with_capacity(5);
- let mut i = i as u32; // avoids sign extension on bitshift
-
- loop {
- if (i & !0x7F) == 0 {
- output.push(i as u8);
- break;
- } else {
- let varint_byte = ((i as u8) & 0x7F) | 0x80;
- output.push(varint_byte);
- i >>= 7;
- }
- }
-
- self.transport
- .write_all(output.as_slice())
- .map_err(From::from)
- }
-
// FIXME: field_type as unconstrained u8 is bad
fn write_field_header(&mut self, field_type: u8, field_id: i16) -> crate::Result<()> {
let field_delta = field_id - self.last_write_field_id;
@@ -441,10 +403,8 @@
} else {
let header = 0xF0 | elem_identifier;
self.write_byte(header)?;
- // size is strictly positive as per the spec, so:
- // 1. we first cast to u32
- // 2. write as varint
- // which means that integer_encoding will **not** zigzag it first
+ // element count is strictly positive as per the spec, so
+ // cast i32 as u32 so that varint writing won't use zigzag encoding
self.transport
.write_varint(element_count as u32)
.map_err(From::from)
@@ -466,7 +426,8 @@
fn write_message_begin(&mut self, identifier: &TMessageIdentifier) -> crate::Result<()> {
self.write_byte(COMPACT_PROTOCOL_ID)?;
self.write_byte((u8::from(identifier.message_type) << 5) | COMPACT_VERSION)?;
- self.write_non_zigzag_varint(identifier.sequence_number)?;
+ // cast i32 as u32 so that varint writing won't use zigzag encoding
+ self.transport.write_varint(identifier.sequence_number as u32)?;
self.write_string(&identifier.name)?;
Ok(())
}
@@ -540,10 +501,8 @@
}
fn write_bytes(&mut self, b: &[u8]) -> crate::Result<()> {
- // size is strictly positive as per the spec, so:
- // 1. we first cast to u32
- // 2. write as varint
- // which means that integer_encoding will **not** zigzag it first
+ // length is strictly positive as per the spec, so
+ // cast i32 as u32 so that varint writing won't use zigzag encoding
self.transport.write_varint(b.len() as u32)?;
self.transport.write_all(b).map_err(From::from)
}
@@ -554,7 +513,7 @@
fn write_i16(&mut self, i: i16) -> crate::Result<()> {
self.transport
- .write_varint(i as i32)
+ .write_varint(i)
.map_err(From::from)
.map(|_| ())
}
@@ -603,10 +562,8 @@
if identifier.size == 0 {
self.write_byte(0)
} else {
- // size is strictly positive as per the spec, so:
- // 1. we first cast to u32
- // 2. write as varint
- // which means that integer_encoding will **not** zigzag it first
+ // element count is strictly positive as per the spec, so
+ // cast i32 as u32 so that varint writing won't use zigzag encoding
self.transport.write_varint(identifier.size as u32)?;
let key_type = identifier