1 files changed, 171 insertions, 0 deletions
diff --git a/third_party/rust/wasmparser-0.48.2/src/readers/operators.rs b/third_party/rust/wasmparser-0.48.2/src/readers/operators.rs
new file mode 100644
index 0000000000..0ecac8d5fb
--- /dev/null
+++ b/third_party/rust/wasmparser-0.48.2/src/readers/operators.rs
@@ -0,0 +1,171 @@
+/* Copyright 2018 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+use super::{BinaryReader, BinaryReaderError, Operator, Result};
+
+#[derive(Clone)]
+pub struct OperatorsReader<'a> {
+    pub(crate) reader: BinaryReader<'a>,
+}
+
+impl<'a> OperatorsReader<'a> {
+    pub(crate) fn new<'b>(data: &'a [u8], offset: usize) -> OperatorsReader<'b>
+    where
+        'a: 'b,
+    {
+        OperatorsReader {
+            reader: BinaryReader::new_with_offset(data, offset),
+        }
+    }
+
+    pub fn eof(&self) -> bool {
+        self.reader.eof()
+    }
+
+    pub fn original_position(&self) -> usize {
+        self.reader.original_position()
+    }
+
+    pub fn ensure_end(&self) -> Result<()> {
+        if self.eof() {
+            return Ok(());
+        }
+        Err(BinaryReaderError {
+            message: "Unexpected data at the end of operators",
+            offset: self.reader.original_position(),
+        })
+    }
+
+    pub fn read<'b>(&mut self) -> Result<Operator<'b>>
+    where
+        'a: 'b,
+    {
+        self.reader.read_operator()
+    }
+
+    pub fn into_iter_with_offsets<'b>(self) -> OperatorsIteratorWithOffsets<'b>
+    where
+        'a: 'b,
+    {
+        OperatorsIteratorWithOffsets {
+            reader: self,
+            err: false,
+        }
+    }
+
+    pub fn read_with_offset<'b>(&mut self) -> Result<(Operator<'b>, usize)>
+    where
+        'a: 'b,
+    {
+        let pos = self.reader.original_position();
+        Ok((self.read()?, pos))
+    }
+}
+
+impl<'a> IntoIterator for OperatorsReader<'a> {
+    type Item = Result<Operator<'a>>;
+    type IntoIter = OperatorsIterator<'a>;
+
+    /// Reads content of the code section.
+    ///
+    /// # Examples
+    /// ```
+    /// # let data: &[u8] = &[0x00, 0x61, 0x73, 0x6d, 0x01, 0x00, 0x00, 0x00,
+    /// #     0x01, 0x4, 0x01, 0x60, 0x00, 0x00, 0x03, 0x02, 0x01, 0x00,
+    /// #     0x0a, 0x05, 0x01, 0x03, 0x00, 0x01, 0x0b];
+    /// use wasmparser::{ModuleReader, Result, Operator};
+    /// let mut reader = ModuleReader::new(data).expect("module reader");
+    /// let section = reader.read().expect("type section");
+    /// let section = reader.read().expect("function section");
+    /// let section = reader.read().expect("code section");
+    /// let mut code_reader = section.get_code_section_reader().expect("code section reader");
+    /// for _ in 0..code_reader.get_count() {
+    ///     let body = code_reader.read().expect("function body");
+    ///     let mut op_reader = body.get_operators_reader().expect("op reader");
+    ///     let ops = op_reader.into_iter().collect::<Result<Vec<Operator>>>().expect("ops");
+    ///     assert!(
+    ///         if let [Operator::Nop, Operator::End] = ops.as_slice() { true } else { false },
+    ///         "found {:?}",
+    ///         ops
+    ///     );
+    /// }
+    /// ```
+    fn into_iter(self) -> Self::IntoIter {
+        OperatorsIterator {
+            reader: self,
+            err: false,
+        }
+    }
+}
+
+pub struct OperatorsIterator<'a> {
+    reader: OperatorsReader<'a>,
+    err: bool,
+}
+
+impl<'a> Iterator for OperatorsIterator<'a> {
+    type Item = Result<Operator<'a>>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.err || self.reader.eof() {
+            return None;
+        }
+        let result = self.reader.read();
+        self.err = result.is_err();
+        Some(result)
+    }
+}
+
+pub struct OperatorsIteratorWithOffsets<'a> {
+    reader: OperatorsReader<'a>,
+    err: bool,
+}
+
+impl<'a> Iterator for OperatorsIteratorWithOffsets<'a> {
+    type Item = Result<(Operator<'a>, usize)>;
+
+    /// Reads content of the code section with offsets.
+    ///
+    /// # Examples
+    /// ```
+    /// # let data: &[u8] = &[0x00, 0x61, 0x73, 0x6d, 0x01, 0x00, 0x00, 0x00,
+    /// #     0x01, 0x4, 0x01, 0x60, 0x00, 0x00, 0x03, 0x02, 0x01, 0x00,
+    /// #     0x0a, 0x05, 0x01, 0x03, 0x00, /* offset = 23 */ 0x01, 0x0b];
+    /// use wasmparser::{ModuleReader, Result, Operator};
+    /// let mut reader = ModuleReader::new(data).expect("module reader");
+    /// let section = reader.read().expect("type section");
+    /// let section = reader.read().expect("function section");
+    /// let section = reader.read().expect("code section");
+    /// let mut code_reader = section.get_code_section_reader().expect("code section reader");
+    /// for _ in 0..code_reader.get_count() {
+    ///     let body = code_reader.read().expect("function body");
+    ///     let mut op_reader = body.get_operators_reader().expect("op reader");
+    ///     let ops = op_reader.into_iter_with_offsets().collect::<Result<Vec<(Operator, usize)>>>().expect("ops");
+    ///     assert!(
+    ///         if let [(Operator::Nop, 23), (Operator::End, 24)] = ops.as_slice() { true } else { false },
+    ///         "found {:?}",
+    ///         ops
+    ///     );
+    /// }
+    /// ```
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.err || self.reader.eof() {
+            return None;
+        }
+        let result = self.reader.read_with_offset();
+        self.err = result.is_err();
+        Some(result)
+    }
+}