diff options
Diffstat (limited to 'third_party/rust/xml-rs/src/reader/mod.rs')
-rw-r--r-- | third_party/rust/xml-rs/src/reader/mod.rs | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/third_party/rust/xml-rs/src/reader/mod.rs b/third_party/rust/xml-rs/src/reader/mod.rs new file mode 100644 index 0000000000..90f5b52c56 --- /dev/null +++ b/third_party/rust/xml-rs/src/reader/mod.rs @@ -0,0 +1,129 @@ +//! Contains high-level interface for a pull-based XML parser. +//! +//! The most important type in this module is `EventReader`, which provides an iterator +//! view for events in XML document. + +use std::io::{Read}; +use std::result; + +use common::{Position, TextPosition}; + +pub use self::config::ParserConfig; +pub use self::events::XmlEvent; + +use self::parser::PullParser; + +mod lexer; +mod parser; +mod config; +mod events; + +mod error; +pub use self::error::{Error, ErrorKind}; + +/// A result type yielded by `XmlReader`. +pub type Result<T> = result::Result<T, Error>; + +/// A wrapper around an `std::io::Read` instance which provides pull-based XML parsing. +pub struct EventReader<R: Read> { + source: R, + parser: PullParser +} + +impl<R: Read> EventReader<R> { + /// Creates a new reader, consuming the given stream. + #[inline] + pub fn new(source: R) -> EventReader<R> { + EventReader::new_with_config(source, ParserConfig::new()) + } + + /// Creates a new reader with the provded configuration, consuming the given stream. + #[inline] + pub fn new_with_config(source: R, config: ParserConfig) -> EventReader<R> { + EventReader { source: source, parser: PullParser::new(config) } + } + + /// Pulls and returns next XML event from the stream. + /// + /// If returned event is `XmlEvent::Error` or `XmlEvent::EndDocument`, then + /// further calls to this method will return this event again. + #[inline] + pub fn next(&mut self) -> Result<XmlEvent> { + self.parser.next(&mut self.source) + } + + pub fn source(&self) -> &R { &self.source } + pub fn source_mut(&mut self) -> &mut R { &mut self.source } + + /// Unwraps this `EventReader`, returning the underlying reader. + /// + /// Note that this operation is destructive; unwrapping the reader and wrapping it + /// again with `EventReader::new()` will create a fresh reader which will attempt + /// to parse an XML document from the beginning. + pub fn into_inner(self) -> R { + self.source + } +} + +impl<B: Read> Position for EventReader<B> { + /// Returns the position of the last event produced by the reader. + #[inline] + fn position(&self) -> TextPosition { + self.parser.position() + } +} + +impl<R: Read> IntoIterator for EventReader<R> { + type Item = Result<XmlEvent>; + type IntoIter = Events<R>; + + fn into_iter(self) -> Events<R> { + Events { reader: self, finished: false } + } +} + +/// An iterator over XML events created from some type implementing `Read`. +/// +/// When the next event is `xml::event::Error` or `xml::event::EndDocument`, then +/// it will be returned by the iterator once, and then it will stop producing events. +pub struct Events<R: Read> { + reader: EventReader<R>, + finished: bool +} + +impl<R: Read> Events<R> { + /// Unwraps the iterator, returning the internal `EventReader`. + #[inline] + pub fn into_inner(self) -> EventReader<R> { + self.reader + } + + pub fn source(&self) -> &R { &self.reader.source } + pub fn source_mut(&mut self) -> &mut R { &mut self.reader.source } + +} + +impl<R: Read> Iterator for Events<R> { + type Item = Result<XmlEvent>; + + #[inline] + fn next(&mut self) -> Option<Result<XmlEvent>> { + if self.finished && !self.reader.parser.is_ignoring_end_of_stream() { None } + else { + let ev = self.reader.next(); + match ev { + Ok(XmlEvent::EndDocument) | Err(_) => self.finished = true, + _ => {} + } + Some(ev) + } + } +} + +impl<'r> EventReader<&'r [u8]> { + /// A convenience method to create an `XmlReader` from a string slice. + #[inline] + pub fn from_str(source: &'r str) -> EventReader<&'r [u8]> { + EventReader::new(source.as_bytes()) + } +} |