QPACK: use err_derive for public errors

quinn-h3/Cargo.toml

@@ -23,11 +23,12 @@ maintenance = { status = "experimental" }
 travis-ci = { repository = "djc/quinn" }
 
 [dependencies]
+quinn-proto = { path = "../quinn-proto", version = "0.2.0" }
+quinn = { path = "../quinn", version = "0.2.0" }
 bytes = "0.4.7"
 bitlab = "0.8.1"
 lazy_static = "1"
-quinn-proto = { path = "../quinn-proto", version = "0.2.0" }
-quinn = { path = "../quinn", version = "0.2.0" }
+err-derive = "0.1.5"
 
 [dev-dependencies]
 proptest = "0.6.0"

quinn-h3/src/qpack/decoder.rs

@@ -1,6 +1,8 @@
 use bytes::{Buf, BufMut};
 use std::io::Cursor;
 
+use err_derive::Error;
+
 use super::static_::{Error as StaticError, StaticTable};
 use super::vas;
 use super::{
@@ -20,16 +22,25 @@ use super::parse_error::ParseError;
 use super::prefix_int;
 use super::prefix_string;
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Error)]
 pub enum Error {
+    #[error(display = "failed to parse integer: {:?}", _0)]
     InvalidInteger(prefix_int::Error),
+    #[error(display = "failed to parse string: {:?}", _0)]
     InvalidString(prefix_string::Error),
+    #[error(display = "index is out of dynamic table bounds: {:?}", _0)]
     InvalidIndex(vas::Error),
+    #[error(display = "dynamic table error: {}", _0)]
     DynamicTableError(DynamicTableError),
+    #[error(display = "index '{}' is out of static table bounds", _0)]
     InvalidStaticIndex(usize),
+    #[error(display = "invalid data prefix")]
     UnknownPrefix,
+    #[error(display = "missing references from dynamic table to decode header block")]
     MissingRefs,
+    #[error(display = "header prefix contains invalid base index: {:?}", _0)]
     BadBaseIndex(isize),
+    #[error(display = "data is unexpectedly truncated")]
     UnexpectedEnd,
 }
 

quinn-h3/src/qpack/dynamic.rs

@@ -3,6 +3,8 @@ use std::collections::btree_map::Entry as BTEntry;
 use std::collections::hash_map::Entry;
 use std::collections::{BTreeMap, HashMap, VecDeque};
 
+use err_derive::Error;
+
 use super::field::HeaderField;
 use super::static_::StaticTable;
 use crate::qpack::vas::{self, VirtualAddressSpace};
@@ -19,15 +21,23 @@ pub const SETTINGS_HEADER_TABLE_SIZE_DEFAULT: usize = 4096;
  */
 const SETTINGS_HEADER_TABLE_SIZE_MAX: usize = 1073741823; // 2^30 -1
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Error)]
 pub enum Error {
+    #[error(display = "bad relative index: {}", _0)]
     BadRelativeIndex(usize),
+    #[error(display = "bad post base index: {}", _0)]
     BadPostbaseIndex(usize),
+    #[error(display = "decoded index out of bounds: {}", _0)]
     BadIndex(usize),
+    #[error(display = "tried to insert a field greater than dynamic table available size")]
     MaxTableSizeReached,
+    #[error(display = "table size setting is greater than maximum authorized")]
     MaximumTableSizeTooLarge,
+    #[error(display = "stream id '{}' is unknown or has already been acknowledged or canceled", _0)]
     UnknownStreamId(u64),
+    #[error(display = "tried to acknowledge encoder stream but no encoder data has been sent")]
     NoTrackingData,
+    #[error(display = "internal reference tracking error")]
     InvalidTrackingCount,
 }
 
@@ -858,9 +868,9 @@ mod tests {
 
         insert_fields(&mut table, vec![HeaderField::new("Name-C", "Value-C")]);
 
-        assert_eq!(table.get(0), Ok(&HeaderField::new("Name-B", "Value-B")));
-        assert_eq!(table.get(1), Ok(&HeaderField::new("Name-C", "Value-C")));
-        assert_eq!(table.get(2), Err(Error::BadIndex(2)));
+        assert_eq!(table.fields.get(0), Some(&HeaderField::new("Name-B", "Value-B")));
+        assert_eq!(table.fields.get(1), Some(&HeaderField::new("Name-C", "Value-C")));
+        assert_eq!(table.fields.get(2), None);
     }
 
     #[test]

quinn-h3/src/qpack/encoder.rs

@@ -1,7 +1,10 @@
-use bytes::{Buf, BufMut};
 use std::cmp;
 use std::io::Cursor;
 
+use bytes::{Buf, BufMut};
+
+use err_derive::Error;
+
 use super::block::{
     HeaderPrefix, Indexed, IndexedWithPostBase, Literal, LiteralWithNameRef,
     LiteralWithPostBaseNameRef,
@@ -20,6 +23,18 @@ use super::stream::{
 };
 use super::HeaderField;
 
+#[derive(Debug, PartialEq, Error)]
+pub enum Error {
+    #[error(display = "failed to insert in dynamic table: {}", _0)]
+    Insertion(DynamicTableError),
+    #[error(display = "prefixed string: {:?}", _0)]
+    InvalidString(StringError),
+    #[error(display = "prefixed integer: {:?}", _0)]
+    InvalidInteger(IntError),
+    #[error(display = "invalid data prefix")]
+    UnknownPrefix,
+}
+
 pub fn encode<W: BufMut>(
     table: &mut DynamicTableEncoder,
     block: &mut W,
@@ -173,14 +188,6 @@ pub fn set_dynamic_table_size<W: BufMut>(
     Ok(())
 }
 
-#[derive(Debug, PartialEq)]
-pub enum Error {
-    Insertion(DynamicTableError),
-    InvalidString(StringError),
-    InvalidInteger(IntError),
-    UnknownPrefix,
-}
-
 impl From<DynamicTableError> for Error {
     fn from(e: DynamicTableError) -> Self {
         Error::Insertion(e)

quinn-h3/src/qpack/mod.rs

@@ -3,18 +3,19 @@ pub use self::decoder::{
 };
 pub use self::dynamic::{
     DynamicTable, DynamicTableDecoder, DynamicTableEncoder, DynamicTableInserter,
-    Error as DynamicTableError,
 };
 pub use self::encoder::{encode, on_decoder_recv, set_dynamic_table_size, Error as EncoderError};
 pub use self::field::HeaderField;
 
+use self::dynamic::Error as DynamicTableError;
+
 mod block;
 mod dynamic;
 mod field;
+mod parse_error;
 mod static_;
 mod stream;
 mod vas;
-mod parse_error;
 
 mod decoder;
 mod encoder;