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//! Alternative implementation of many functions found in [`std::io`][stdio], //! but suitable for blocking IO over networks. //! //! The main reason for this crate is the handling of [`ErrorKind::Interrupted`][errorkind] in //! `std::io`. //! Except for [`Read::read()`][readread] and [`Write::write()`][writewrite], almost all functions //! will ignore interrupts and just retry. //! //! This crate provides alternative implementations using a similar API but allow for interrupts //! whithout losing any content. //! //! Most functions are based on [`BufRead`][bufread] instead of [`Read`][read] to ensure that no //! content is lost on retry. //! //! [stdio]: https://doc.rust-lang.org/nightly/std/io/index.html //! [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html //! [read]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html //! [bufread]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html //! [readread]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html#tymethod.read //! [writewrite]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html#tymethod.write extern crate memchr; extern crate buf_redux as br; use std::{io, str}; mod impls; mod adapt; mod iter; pub mod mock; pub use adapt::{Retry, Take, Repeat}; pub use iter::{Bytes, Chars, Split, Collect}; /// Copies the entire content of a buffered reader into a writer. /// /// Similar to [`std::io::copy`][copy], this function will continuously read data from reader and /// then write it into writer in a streaming fashion until reader returns EOF. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`fill_buf`][fillbuf] or /// [`write`][writewrite] returns any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// All bytes consumed from the buffered reader will be written to the specified writer and vice /// versa. /// It is guaranteed that no data is lost in case of error. /// /// Differences to `std::io::copy` /// ============================== /// - Does not retry on [`ErrorKind::Interrupted`][errorkind]. /// - Uses [`BufRead`][bufread] instead of [`Read`][read]. /// - Does not return the number of bytes that are copied. /// /// Advantages /// ---------- /// - Allows for reliable retry on errors. /// - Function is interruptable, e.g. to allow graceful shutdown for server applications. /// - Avoids double buffering if the source already implements [`BufRead`][bufread]. /// - Allows different buffer sizes by using [`BufReader::with_capacity`][withcap]. /// /// Disadvantages /// ------------- /// The fact that it does not return the number of bytes copied stems from the fact that it cannot /// return this information in case of error. /// This would go against the goal of allowing reliable retry. /// /// [copy]: https://doc.rust-lang.org/nightly/std/io/fn.copy.html /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf /// [writewrite]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html#tymethod.write /// [bufread]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html /// [read]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html /// [withcap]: https://doc.rust-lang.org/nightly/std/io/struct.BufReader.html#method.with_capacity pub fn copy<R: ?Sized, W: ?Sized>(reader: &mut R, writer: &mut W) -> io::Result<()> where R: io::BufRead, W: io::Write { loop { let written = { let buf = try!(reader.fill_buf()); if buf.len() == 0 { return Ok(()); } try!(writer.write(buf)) }; if written == 0 { return Err(io::Error::new(io::ErrorKind::WriteZero, "no bytes could be written")); } reader.consume(written); } } /// Copies the content of a buffered reader into a writer until a delimiter is reached. /// /// This function will continuously read data from reader and then write it into writer in a /// streaming fashion until until the delimiter or EOF is found. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`fill_buf`][fillbuf] or /// [`write`][writewrite] returns any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// All bytes consumed from the buffered reader will be written to the specified writer and vice /// versa. /// It is guaranteed that no data is lost in case of error. /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf /// [writewrite]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html#tymethod.write pub fn copy_until<R: ?Sized, W: ?Sized>(reader: &mut R, writer: &mut W, delim: u8) -> io::Result<()> where R: io::BufRead, W: io::Write { loop { let (found, used) = { let buf = try!(reader.fill_buf()); if buf.len() == 0 { return Err(io::Error::new(io::ErrorKind::UnexpectedEof, "Stream did not contain the delimiter")); } match memchr::memchr(delim, buf) { Some(i) => { let written = try!(writer.write(&buf[..i + 1])); (written == i + 1, written) } None => (false, try!(writer.write(buf))), } }; if used == 0 { return Err(io::Error::new(io::ErrorKind::WriteZero, "no bytes could be written")); } reader.consume(used); if found { return Ok(()); } } } /// Alternative to `std::io::Read` /// /// This trait is automatically implemented for all types that implement [`std::io::Read`]. /// /// Diffrerences to `std::io::Read` /// =============================== /// Methods that are just wrappers around the equivalent methods of `std::io::Read`: /// /// - `read` /// - `by_ref` /// - `chain` /// /// Methods that provide a slightly different functionality than their counterparts in /// `std::io::Read`: /// /// - `take` /// /// New methods that have no counterpart in `std::io::Read`: /// /// - `buffer` /// - `retry` /// - `repeat` /// /// Functions that were removed or moved to a different trait, /// because they cannot be implemented with providing all desired guarantees: /// /// - `read_to_end` -> moved to [`BufRead`] /// - `read_to_string` -> moved to [`BufReadGrow`] /// - `read_exact` -> moved to [`BufRead`] /// - `bytes` -> moved to [`BufRead`] /// - `chars` -> moved to [`BufReadGrow`] /// /// [`std::io::Read`]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html /// [`BufRead`]: trait.BufRead.html /// [`BufReadGrow`]: trait.BufReadGrow.html pub trait Read: io::Read { /// Pull some bytes from this source into the specified buffer, returning /// how many bytes were read. /// /// This is just a "reexport" of [`std::io::Read::read`][readread] provided for convenience. /// /// [readread]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html#tymethod.read #[inline] fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { io::Read::read(self, buf) } /// Creates a "by reference" adaptor for this instance of `Read`. /// /// This is just a "reexport" of [`std::io::Read::by_ref`][byref] provided for convenience. /// /// [byref]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html#tymethod.by_ref #[inline] fn by_ref(&mut self) -> &mut Self where Self: Sized { io::Read::by_ref(self) } /// Creates an adaptor which will chain this stream with another. /// /// This is just a "reexport" of [`std::io::Read::chain`][chain] provided for convenience. /// /// [chain]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html#tymethod.chain #[inline] fn chain<R: io::Read>(self, next: R) -> io::Chain<Self, R> where Self: Sized { io::Read::chain(self, next) } /// Creates an adapter which will read at most `limit` bytes from it. /// /// This function returns a new instance of `Read` which will read at most /// `limit` bytes, after which it will always return EOF (`Ok(0)`). Any /// read errors will not count towards the number of bytes read and future /// calls to `read` may succeed. /// /// See also [`Write::take`]. /// /// Differences to `std::io::Read::take` /// ==================================== /// This function is equivalent to [`std::io::Read::take`][iotake] except that the returned /// adapter implements [`BufReadGrow`] and [`std::io::Write`] if possible. /// /// [`Write::take`]: trait.Write.html#method.take /// [iotake]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.take /// [`BufReadGrow`]: trait.BufReadGrow.html /// [`std::io::Write`]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html #[inline] fn take(self, limit: u64) -> Take<Self> where Self: Sized { Take::new(self, limit) } /// Creates a buffered reader with default capacity and default strategies /// /// Please see the documentation of [`buf_redux::BufReader`][bufreader] for more details /// /// [bufreader]: ../buf_redux/struct.BufReader.html #[inline] fn buffer(self) -> br::BufReader<Self, br::DefaultReadStrategy, br::DefaultMoveStrategy> where Self: Sized { br::BufReader::new(self) } /// Transforms this reader into a reader that automatically retries on interrupts /// /// The returned adapter will behave identically to the original reader, except that it retries /// the reading operation automatically if an error of kind /// [`ErrorKind::Interrupted`][errorkind] occurs. /// /// Note /// ---- /// Methods that are already expected to retry are forwarded directly to the underlying reader. /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html #[inline] fn retry(self) -> Retry<Self> where Self: Sized { Retry::new(self) } /// Transforms this reader into a reader that automatically restarts from the beginning after /// EOF is reached #[inline] fn repeat(self) -> Repeat<Self> where Self: Sized { Repeat::new(self) } } impl<R: io::Read> Read for R {} /// Alternative to `std::io::Write` /// /// This trait is automatically implemented for all types that implement `std::io::Write`. /// /// Differences to `std::io::Write` /// =============================== /// Methods that are just wrappers around the equivalent methods of `std::io::Write`: /// /// - `write` /// - `flush` /// - `by_ref` /// /// Methods that provide a slightly different functionality than their counterparts in /// `std::io::Write`: /// /// - `write_all` /// /// New methods that have no counterpart in `std::io::Write`: /// /// - `retry` /// - `take` /// /// Functions that were removed or moved to a different trait, /// because they cannot be implemented with providing all desired guarantees: /// /// - `write_fmt` pub trait Write: io::Write { /// Write a buffer into this object, returning how many bytes were written. /// /// This is just a "reexport" of [`std::io::Write::write`][write] provided for convenience. /// /// [write]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html#tymethod.write #[inline] fn write(&mut self, buf: &[u8]) -> io::Result<usize> { io::Write::write(self, buf) } /// Flush this output stream, ensuring that all intermediately buffered /// contents reach their destination. /// /// This is just a "reexport" of [`std::io::Write::flush`][flush] provided for convenience. /// /// [flush]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html#tymethod.flush #[inline] fn flush(&mut self) -> io::Result<()> { io::Write::flush(self) } /// Attempts to write an entire buffer into this write. /// /// Similarly to [`std::io::Write::write_all`][iowriteall], /// this method will continuously call `write` while there is more data to write. /// This method will not return until the entire buffer has been /// successfully written or an error occurs. The first error generated from /// this method will be returned. /// /// The supplied buffer will be consumed by the writing operation. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`write`][writewrite] returns /// any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// All bytes consumed from the buffer will be written to the the writer and vice versa. /// It is guaranteed that no data is lost in case of error. /// /// Differences to `std::io::Write::write_all` /// ========================================== /// - Does not retry on [`ErrorKind::Interrupted`][errorkind]. /// - Takes a `BufRead` instance instead of just a plain `&[u8]`. /// /// Advantages /// ---------- /// - Function is interruptable, e.g. to allow graceful shutdown for server applications. /// - In case of error, it is always clear how much data was already written. No data is lost. /// /// [iowriteall]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html#method.write_all /// [writewrite]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html#tymethod.write /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html #[inline] fn write_all<R: BufRead + ?Sized>(&mut self, buf: &mut R) -> io::Result<()> { copy(buf, self) } /// Creates a "by reference" adaptor for this instance of `Write`. /// /// This is just a "reexport" of [`std::io::Write::by_ref`][byref] provided for convenience. /// /// [byref]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html#tymethod.by_ref #[inline] fn by_ref(&mut self) -> &mut Self where Self: Sized { io::Write::by_ref(self) } /// Transforms this writer into a writer that automatically retries on interrupts /// /// The returned adapter will behave identically to the original writer, /// except that it retries the writing operation automatically if an error of kind /// [`ErrorKind::Interrupted`][errorkind] occurs. /// /// Note /// ---- /// Methods that are already expected to retry are forwarded directly to the underlying writer. /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html #[inline] fn retry(self) -> Retry<Self> where Self: Sized { Retry::new(self) } /// Creates an adapter which will write at most `limit` bytes to it. /// /// This function returns a new instance of `Write` which will write at most /// `limit` bytes, after which it will always return Ok(0). /// Any write errors will not count towards the number of bytes written and future /// calls to `write` may succeed. /// /// This function is equivalent to `std::io::Read::take` but the returened adapter implements /// `Write`. /// /// See also [`Read::take`]. /// /// [`Read::take`]: trait.Read.html#method.take #[inline] fn take(self, limit: u64) -> Take<Self> where Self: Sized { Take::new(self, limit) } } impl<W: io::Write> Write for W {} /// Alternative to `std::io::BufRead` /// /// This trait is automatically implemented for all types that implement `std::io::BufRead`. /// /// Differences to `std::io::BufRead` /// ================================= /// Methods that are just wrappers around the equivalent methods of `std::io::BufRead`: /// /// - `fill_buf` /// - `consume` /// /// Methods that provide a slightly different functionality than their counterparts in /// `std::io::BufRead`: /// /// - `read_until` /// - `split` /// /// Methods originally implemented in a different trait: /// /// - `read_to_end` from [`std::io::Read`][ioread] /// - `read_exact` from [`std::io::Read`][ioread] /// - `bytes` from [`std::io::Read`][ioread] /// /// New methods that have no counterpart in `std::io`: /// /// - `skip_to_end` /// - `skip_until` /// /// Functions that were removed or moved to a different trait, /// because they cannot be implemented with providing all desired guarantees: /// /// - `read_line` moved to [`BufReadGrow`] /// /// [ioread]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html /// [`BufReadGrow`]: trait.BufReadGrow.html pub trait BufRead: io::BufRead { /// Fills the internal buffer of this object, returning the buffer contents. /// /// This is just a "reexport" of [`std::io::BufRead::fill_buf`][fillbuf] provided for /// convenience. /// /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf #[inline] fn fill_buf(&mut self) -> io::Result<&[u8]> { io::BufRead::fill_buf(self) } /// Tells this buffer that `amt` bytes have been consumed from the buffer, /// so they should no longer be returned in calls to `read`. /// /// This is just a "reexport" of [`std::io::BufRead::consume`][consume] provided for /// convenience. /// /// [consume]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.consume #[inline] fn consume(&mut self, amt: usize) { io::BufRead::consume(self, amt) } // ============================================================================================ // Methods originally implemented in std::io::Read // ============================================================================================ /// Read all bytes until EOF in this source, placing them into `buf`. /// /// Similar to [`std::io::Read::read_to_end`][readtoend], all bytes read from this source will /// be appended to the specified buffer `buf`. /// /// This function will continuously call [`fill_buf`][fillbuf] and [`consume`][consume] to /// append more data to `buf` until [`fill_buf`][fillbuf] returns either `Ok(&[])` or any kind /// of error. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`fill_buf`][fillbuf] returns /// any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// All bytes consumed from the reader will be written to the buffer and vice versa. /// It is guaranteed that no data is lost in case of error. /// /// Differences to `std::io::Read::read_to_end` /// =========================================== /// - Does not retry on [`ErrorKind::Interrupted`][errorkind]. /// - Uses [`BufRead`][bufread] instead of [`Read`][read]. /// - Does not return the number of bytes that are copied. /// - Works with all kind of writers, not just `Vec<u8>` /// /// Advantages /// ---------- /// - Function is interruptable, e.g. to allow graceful shutdown for server applications. /// - Avoids double buffering if the source already implements [`BufRead`][bufread]. /// - Allows different buffer sizes by using [`BufReader::with_capacity`][withcap]. /// /// Disadvantages /// ------------- /// The fact that it does not return the number of bytes copied stems from the fact that it /// cannot return this information in case of error. /// This would go against the goal of allowing reliable retry. /// /// [readtoend]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read_to_end /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf /// [consume]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.consume /// [bufread]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html /// [read]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html /// [withcap]: /// https://doc.rust-lang.org/nightly/std/io/struct.BufReader.html#method.with_capacity #[inline] fn read_to_end<R: Write + ?Sized>(&mut self, buf: &mut R) -> io::Result<()> { copy(self, buf) } /// Skip all bytes until EOF in this source. /// /// Acts like [`read_to_end`], but all bytes read from this source are /// discarded. /// /// This function will continuously call [`fill_buf`][fillbuf] and [`consume`][consume] until /// [`fill_buf`][fillbuf] returns either `Ok(&[])` or any kind of error. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`fill_buf`][fillbuf] returns /// any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// [`read_to_end`]: #method.read_to_end /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf /// [consume]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.consume #[inline] fn skip_to_end(&mut self) -> io::Result<()> { copy(self, &mut io::sink()) } /// Read the exact number of bytes required to fill `buf`. /// /// Similarliy to [`std::io::Read::read_exact`][readexact], this function reads as many bytes /// as necessary to completely fill the specified buffer `buf`. /// /// No guarantees are provided about the contents of `buf` when this /// function is called, implementations cannot rely on any property of the /// contents of `buf` being true. It is recommended that implementations /// only write data to `buf` instead of reading its contents. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`fill_buf`][fillbuf] returns /// any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// If this function encounters an "end of file" before completely filling /// the buffer, it returns an error of the kind [`ErrorKind::UnexpectedEof`][errorkind]. /// /// If this function returns an error, the buffer will contain all bytes read up to that point. /// The position of the cursor will point one byte past the last read byte. /// /// All bytes consumed from the reader will be written to the buffer and vice versa. /// It is guaranteed that no data is lost in case of error. /// /// Differences to `std::io::Read::read_exact` /// ========================================== /// - Does not retry on [`ErrorKind::Interrupted`][errorkind]. /// - Uses [`BufRead`][bufread] instead of [`Read`][read]. /// - In case of error the buffer contains all bytes read up to that point. /// - Takes a [`Cursor`][cursor] instead of plain buffer to track the current position. /// /// Advantages /// ---------- /// - Function is interruptable, e.g. to allow graceful shutdown for server applications. /// - No data ist lost on error. /// /// Disadvantages /// ------------- /// The function is slightly less ergonomic to use. /// /// [readexact]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read_exact /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf /// [bufread]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html /// [read]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html /// [cursor]: https://doc.rust-lang.org/nightly/std/io/struct.Cursor.html fn read_exact(&mut self, buf: &mut io::Cursor<&mut [u8]>) -> io::Result<()> { let mut remaining = buf.get_ref().len() - buf.position() as usize; while remaining > 0 { let written = { let available = try!(BufRead::fill_buf(self)); if available.len() == 0 { return Err(io::Error::new(io::ErrorKind::UnexpectedEof, "Stream is already at EOF")); } try!(buf.write(available)) }; remaining -= written; BufRead::consume(self, written); } Ok(()) } /// Transforms this [`BufRead`][bufread] instance to an [`Iterator`][iterator] over its bytes. /// /// This method is approximately equivalent to [`std::io::Read::bytes`][bytes]. /// /// The returned type implements [`Iterator`][iterator] /// where the `Item` is `Result<u8, R::Err>`. /// The yielded item is `Ok` if a byte was successfully read and /// `Err` otherwise for I/O errors. EOF is mapped to returning `None` from /// this iterator. /// /// Errors /// ====== /// If fill_buf returns any kind of error, the iterator yields `Some(Err)`. In case of error /// it is safe to iterate further to retry the reading operation. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by the iterator. /// /// Differences to `std::io::Read::bytes` /// ===================================== /// - Uses [`BufRead`][bufread] instead of [`Read`][read]. /// /// Advantages /// ---------- /// - No accidentialy unbuffered reading of single bytes /// /// [iterator]: https://doc.rust-lang.org/nightly/std/iter/trait.Iterator.html /// [bufread]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html /// [bytes]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.bytes /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [read]: https://doc.rust-lang.org/nightly/std/io/trait.Read.html #[inline] fn bytes(self) -> Bytes<Self> where Self: Sized { Bytes::new(self) } // ============================================================================================ // Methods originally implemented in std::io::BufRead // ============================================================================================ /// Read all bytes into a buffer until a delimiter is reached. /// /// Similar to [`std::io::BufRead::read_until`][readuntil] ,this function will read bytes from /// the underlying stream and push them to the specified buffer `buf`, until the delimiter /// `delim` is found. If the delimiter is found, it is also part of the result. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`fill_buf`][fillbuf] returns /// any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// If this reader has reached EOF then this function will return /// [`ErrorKind::UnexpectedEof`][errorkind]. /// /// All bytes consumed from the buffered reader will be written to the specified buffer and /// vice versa. /// It is guaranteed that no data is lost in case of error. /// /// Differences to `std::io::BufRead::read_until` /// ============================================= /// - Does not retry on [`ErrorKind::Interrupted`][errorkind]. /// - Does not return the number of bytes that are read. /// - Returns an error on EOF instead of success. /// - Works with all kind of writers, not just `Vec<u8>` /// /// Advantages /// ---------- /// - Function is interruptable, e.g. to allow graceful shutdown for server applications. /// /// Disadvantages /// ------------- /// The fact that it does not return the number of bytes copied stems from the fact that it /// cannot return this information in case of error. /// This would go against the goal of allowing reliable retry. /// /// [readuntil]: http://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#method.read_until /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf #[inline] fn read_until<W: Write + ?Sized>(&mut self, delim: u8, buf: &mut W) -> io::Result<()> { copy_until(self, buf, delim) } /// Skips all bytes until a delimiter is reached. /// /// This function will discard bytes from the underlying stream until the delimiter `delim` is /// found. /// /// Acts like [`read_until`], but all bytes read from this source are /// discarded. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`fill_buf`][fillbuf] returns /// any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// If this reader has reached EOF then this function will return /// [`ErrorKind::UnexpectedEof`][errorkind]. /// /// [`read_until`]: #method.read_until /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf #[inline] fn skip_until(&mut self, delim: u8) -> io::Result<()> { copy_until(self, &mut io::sink(), delim) } /// Returns an iterator over the contents of this reader split on a delimiter. /// /// The iterator returned from this function will return instances of /// `io::Result<Vec<u8>>`. Each vector returned will *not* have the /// delimiter byte at the end. /// /// Errors /// ====== /// The iterator will yield an error whenever [`read_until`] would have also /// returned an error. /// /// [`read_until`]: #method.read_until #[inline] fn split(self, byte: u8) -> Split<Self> where Self: Sized { Split::new(self, byte) } } impl<R: io::BufRead> BufRead for R {} fn utf8_valid_up_to(buf: &[u8]) -> io::Result<usize> { match str::from_utf8(buf) { Ok(_) => Ok(buf.len()), Err(e) if e.valid_up_to() > 0 => Ok(e.valid_up_to()), Err(_) if buf.len() > 4 => { Err(io::Error::new(io::ErrorKind::InvalidData, "stream did not contain valid UTF-8")) } // TODO: improve UTF-8 validity test Err(_) => Ok(0), } } fn find2(delims: (u8, u8), buf: &[u8]) -> usize { let mut start = 0; while let Some(i) = memchr::memchr(delims.0, &buf[start..]) { let current = start + i; if (current == buf.len() - 1) || (buf[current + 1] == delims.1) { return current; } start = current + 1; } buf.len() } /// A `BufReadGrow` is a `BufRead`er that has the ability to read additional data even if the /// buffer is not empty. /// /// A `BufRead` guarantees an internal buffer of at only one byte with no possibility to read /// additional data without consuming the already read data first. /// With this limitation it is not possible to implement many functions in an interrupt-safe way. /// /// Interrupt-safe function require that - when the function returns - all data is either left in /// the stream or appended to the buffer. /// But for example when read UTF-8 with a `BufRead`er, /// this requirement can only be met by appending incomplete UTF-8 to the buffer which is also /// unacceptable by itself. /// /// For that reason, the `BufReadGrow` trait is introduced which extends `BufRead` by a method to /// grow the internal buffer. /// This requires the buffer to be able to relocate the data in the internal buffer. pub trait BufReadGrow: io::BufRead { /// Grows the internal buffer of this object by at least one byte, /// returning the buffer contents. /// /// Like `BufRead::fill_buf`, this function is a lower-level call. /// It needs to be paired with the [`consume`] method to function properly. /// When calling this method, none of the contents will be "read" in the sense that later /// calling `read` may return the same contents. As such, `consume` must be /// called with the number of bytes that are consumed from this buffer to /// ensure that the bytes are never returned twice. /// /// Errors /// ====== /// - Any error returned by the underlying call to `read` will be returned immediately. /// - If the stream has already reached EOF, an error of kind /// [`ErrorKind::UnexpectedEof`][errorkind] is returned. /// - If the internal buffer of is full, an appropriate error is returned. /// Since there is no specific `ErrorKind` for this, [`ErrorKind::Other`][errorkind] /// should be used. /// /// [`fill_buf`]: trait.BufRead.html#tymethod.fill_buf /// [`consume`]: trait.BufRead.html#tymethod.consume /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html fn grow_buf(&mut self) -> io::Result<&[u8]>; /// Fills the internal buffer to at least the specified amount, /// returning the buffer contents. /// /// Like [`BufRead::fill_buf`][`fill_buf`] and [`grow_buf`], this function is a lower-level call. /// It needs to be paired with the [`consume`] method to function properly. /// When calling this method, none of the contents will be "read" in the sense that later /// calling `read` may return the same contents. As such, `consume` must be /// called with the number of bytes that are consumed from this buffer to /// ensure that the bytes are never returned twice. /// /// Errors /// ====== /// - Any I/O error will be returned immediately. /// - If the stream has already reached EOF, an error of kind /// [`ErrorKind::UnexpectedEof`][errorkind] is returned. /// - If the internal buffer of is full, an appropriate error is returned. /// See [`grow_buf`] for more details. /// /// [`fill_buf`]: trait.BufRead.html#tymethod.fill_buf /// [`consume`]: trait.BufRead.html#tymethod.consume /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [`grow_buf`]: #tymethod.grow_buf fn fill_buf_min(&mut self, size: usize) -> io::Result<&[u8]> { match try!(self.fill_buf()).len() { 0 => Err(io::Error::new(io::ErrorKind::UnexpectedEof, "Unexpected end of stream")), n if n == size - 1 => self.grow_buf(), n if n < size => { while try!(self.grow_buf()).len() < size { } self.fill_buf() } _ => self.fill_buf(), } } /// Read all bytes into a buffer until two consecutive delimiters are reached. /// /// This function will read bytes from the underlying stream and push them to the specified /// buffer `buf`, until the two consecutive delimiters `delims` are found. /// If the delimiters are found, they also part of the result. /// /// Errors /// ====== /// This function will return an error immediately if a call to [`fill_buf`][fillbuf] returns /// any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// If this reader has reached EOF then this function will return /// [`ErrorKind::UnexpectedEof`][errorkind]. /// /// In case of an error, all bytes read up to that point are appended to the buffer and /// consumed from this buffered reader. /// There's one notable exception to that rule: If the last byte in the buffer would be the /// first delimiter, it is left in the buffered reader. /// Otherwise retrying on error would not work reliably. /// /// In any case, all bytes consumed from the buffered reader will be written to the specified /// buffer and vice versa. /// It is guaranteed that no data is lost in case of error. /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf fn read_until2(&mut self, delims: (u8, u8), buf: &mut Vec<u8>) -> io::Result<()> { let mut extend = false; loop { let (done, used) = { let available = if extend { try!(self.grow_buf()) } else { try!(self.fill_buf()) }; if available.len() == 0 { return Err(io::Error::new(io::ErrorKind::UnexpectedEof, "Stream did not contain the delimiters")); } extend = false; let found = find2(delims, available); let (done, used) = if found == available.len() { (false, found) } else if found == available.len() - 1 { extend = true; (false, found) } else { (true, found + 2) }; buf.extend_from_slice(&available[..used]); (done, used) }; self.consume(used); if done { return Ok(()); } } } /// Skip all bytes until two consecutive delimiters are reached. /// /// This function will discard bytes from the underlying stream until the two consecutive /// delimiters `delims` are found. /// /// Errors /// ====== /// This function will return an error immediately if a call to [`fill_buf`][fillbuf] returns /// any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// If this reader has reached EOF then this function will return /// [`ErrorKind::UnexpectedEof`][errorkind]. /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf fn skip_until2(&mut self, delims: (u8, u8)) -> io::Result<()> { let mut extend = false; loop { let (done, used) = { let available = if extend { try!(self.grow_buf()) } else { try!(self.fill_buf()) }; if available.len() == 0 { return Err(io::Error::new(io::ErrorKind::UnexpectedEof, "Stream did not contain the delimiters")); } extend = false; let found = find2(delims, available); let (done, used) = if found == available.len() { (false, found) } else if found == available.len() - 1 { extend = true; (false, found) } else { (true, found + 2) }; (done, used) }; self.consume(used); if done { return Ok(()); } } } /// Fills the internal buffer of this object, returning the buffer content as a string /// /// This function will return at least one valid `char` except when reaching EOF. /// If invalid or incomplete UTF-8 is encountered, the function returns all valid UTF-8 up to /// that point. /// /// If the function returns an empty slice, the unterlying reader has reached EOF and all data /// in the stream was valid UTF-8. /// /// Errors /// ====== /// - If either `fill_buf` or `grow_buf` return an error, this error is returned immediately. /// - If invalid UTF-8 is encountered at the beginning of the buffer, an error of kind /// [`ErrorKind::InvalidData`][errorkind] is returned. /// - If an incomplete UTF-8 character followed by EOF is encountered at the beginning of the /// buffer, an error of kind [`ErrorKind::UnexpectedEof`][errorkind] is returned. /// /// Issues /// ====== /// Currently there's no way to decide if the remaining data is an incomplete UTF-8 char or /// just plain invalid UTF-8 if the remaining buffer is smaller or equal than 4 bytes. /// (Issue [`rust-lang/rust#32584`][issue]) /// /// This case is currently just interpreted as [`ErrorKind::UnexpectedEof`][errorkind]. /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [issue]: https://github.com/rust-lang/rust/issues/32584 fn fill_buf_str(&mut self) -> io::Result<&str> { let (buflen, mut valid_up_to) = { let buf = try!(self.fill_buf()); (buf.len(), try!(utf8_valid_up_to(buf))) }; if buflen != 0 { while valid_up_to == 0 { valid_up_to = try!(utf8_valid_up_to(try!(self.grow_buf()))); } } let buf = try!(self.fill_buf()); Ok(str::from_utf8(&buf[0..valid_up_to]).expect("Buffer content is not valid UTF-8")) } /// Grows the internal buffer of this object by at least one char, /// returning the buffer content as a string /// /// This function will return at least one additional valid `char` compared to a call to /// `fill_buf_str`. /// If invalid or incomplete UTF-8 is encountered, the function returns all valid UTF-8 up to /// that point. /// /// If the function returns an empty slice, the unterlying reader has reached EOF and all data /// in the stream was valid UTF-8. /// /// Errors /// ====== /// - If either `fill_buf` or `grow_buf` return an error, this error is returned immediately. /// - If invalid UTF-8 is encountered at the beginning of the buffer s.t. no additional char /// can be returned, an error of kind [`ErrorKind::InvalidData`][errorkind] is returned. /// - If EOF is encountered, such that no additional char can be returned, an error of kind /// [`ErrorKind::UnexpectedEof`][errorkind] is returned. /// /// Issues /// ====== /// Currently there's no way to decide if the remaining data is an incomplete UTF-8 char or /// just plain invalid UTF-8 if the remaining buffer is smaller or equal than 4 bytes. /// (Issue [`rust-lang/rust#32584`][issue]) /// /// This case is currently just interpreted as [`ErrorKind::UnexpectedEof`][errorkind]. /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [issue]: https://github.com/rust-lang/rust/issues/32584 fn grow_buf_str(&mut self) -> io::Result<&str> { let start = try!(utf8_valid_up_to(try!(self.fill_buf()))); let mut valid_up_to = start; while valid_up_to == start { let buf = try!(self.grow_buf()); valid_up_to += try!(utf8_valid_up_to(&buf[valid_up_to..])); } let buf = try!(self.fill_buf()); Ok(str::from_utf8(&buf[0..valid_up_to]).expect("Buffer content is not valid UTF-8")) } /// Read all bytes until EOF in this source, placing them into a string. /// /// This function will continuously call [`fill_buf`][fillbuf]/[`grow_buf`][growbuf] and /// [`consume`][consume] to append more data to `buf` until [`fill_buf`][fillbuf] returns /// either `Ok(&[])` or any kind of error occurs. /// /// Errors /// ====== /// This function will return an error immediately if any call to [`fill_buf`][fillbuf] or /// [`grow_buf`][growbuf] returns any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// If invalid UTF-8 is encountered, an error of kind [`ErrorKind::InvalidData`][errorkind] is /// returned and the string will contain all valid UTF-8 up to that point. /// /// All bytes consumed from the reader will be written to the buffer and vice versa. /// It is guaranteed that no data is lost in case of error. /// /// Differences to `std::io::Read::read_to_string` /// ============================================== /// - Does not retry on [`ErrorKind::Interrupted`][errorkind]. /// - Uses `BufReadGrow` instead of [`BufRead`][bufread]. /// - Does not return the number of bytes that are copied. /// - On error, string will contain all valid UTF-8 up to that point. /// /// Advantages /// ---------- /// - Function is interruptable, e.g. to allow graceful shutdown for server applications. /// - No data ist lost on error (e.g. invalid UTF-8). /// /// Disadvantages /// ------------- /// The fact that it does not return the number of bytes copied stems from the fact that it /// cannot return this information in case of error. /// This would go against the goal of allowing reliable retry. /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf /// [growbuf]: ./trait.BufReadGrow.html#tymethod.grow_buf /// [consume]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.consume /// [bufread]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html fn read_to_string(&mut self, buf: &mut String) -> io::Result<()> { loop { let written = { let available = try!(self.fill_buf_str()); if available.is_empty() { return Ok(()); } buf.push_str(available); available.len() }; self.consume(written); } } /// Read all bytes until a CRLF is reached, and append them to the provided buffer. /// /// This function will UTF-8 characters from the underlying stream and append them to the 'buf' /// until the CRLF delimiter (the 0xA 0xD bytes) is found. /// /// Errors /// ====== /// Like `read_until2`, this function will return an error immediately if a call to /// [`fill_buf`][fillbuf] returns any kind of error. /// Instances of [`ErrorKind::Interrupted`][errorkind] are *not* handled by this function. /// /// This function will return an error of kind [`ErrorKind::InvalidData`][errorkind] if the /// read bytes are not valid UTF-8. /// If EOF is reached, an error of kind [`ErrorKind::UnexpectedEof`][errorkind] is returned. /// /// If any kind of error occurs, the buffer will contain all valid UTF-8 up to that point. /// /// In any case, all bytes consumed from the buffered reader will be written to the specified /// buffer and vice versa. /// It is guaranteed that no data is lost in case of error. /// /// The read buffer will never contain a CR (`\r`) as last character, even in case of error. /// Doing so could lead to skipping a CRLF sequence in case of retry. /// In case of `ErrorKind::UnexpectedEof`, this behavior is a bit unexpected and may /// change in a future version. /// /// Differences to `std::io::BufRead::read_line` /// ============================================ /// - Does not retry on [`ErrorKind::Interrupted`][errorkind]. /// - Does not return the number of bytes that are read. /// - Returns an error on EOF instead of success. /// - Uses CRLF as line ending convention instead of just LF. /// /// Advantages /// ---------- /// - Function is interruptable, e.g. to allow graceful shutdown for server applications. /// - Suitable for network protocols, because those usually use CRLF as line endings. /// /// Disadvantages /// ------------- /// The fact that it does not return the number of bytes copied stems from the fact that it /// cannot return this information in case of error. /// This would go against the goal of allowing reliable retry. /// /// [fillbuf]: https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html#tymethod.fill_buf /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html fn read_line(&mut self, buf: &mut String) -> io::Result<()> { let mut extend = false; loop { let (done, used) = { let available = if extend { try!(self.grow_buf_str()) } else { try!(self.fill_buf_str()) }; if available.is_empty() { return Err(io::Error::new(io::ErrorKind::UnexpectedEof, "Stream did not contain the delimiters")); } extend = false; let found = find2((b'\r', b'\n'), available.as_bytes()); let (done, used) = if found == available.len() { (false, found) } else if found == available.len() - 1 { extend = true; (false, found) } else { (true, found + 2) }; buf.push_str(&available[..used]); (done, used) }; self.consume(used); if done { return Ok(()); } } } /// Transforms this reader to an `Iterator` over `char`s. /// /// Similar to `std::io::Read::chars`, this adaptor will attempt to interpret this reader /// as a UTF-8 encoded sequence of characters. /// The returned iterator will return `None` once /// EOF is reached for this reader. Otherwise each element yielded will be a /// `io::Result<char>`. /// /// Errors /// ====== /// In any call to `fill_buf` or `grow_buf` returns any kind of error, /// this error is yielded by the iterator. /// If invalid UTF-8 is encountered an error of kind [`ErrorKind::InvalidData`][errorkind] is /// yielded. /// If the stream is reaching EOF in the middle of an otherwise valid UTF-8 characters, /// an error of kind [`ErrorKind::UnexpectedEof`][errorkind] is yielded. /// /// Errors of kind ErrorKind::Interrupted are *not* handled by the iterator itself but /// treated as any other kind of error. /// In case of an error, the iterator will not skip any data. /// Iterating further will simply retry the failed operation. /// /// *Note: Ignoring errors will most likely "end" in an endless loop* /// /// Differences to std::io::Read::Chars /// =================================== /// - Errors of kind [`ErrorKind::Interrupted`][errorkind] are not swallowed. /// - Uses the usual [`io::Error`] instead of a custom error type. /// - Invalid UTF-8 is not skipped. /// /// Issues /// ====== /// Currently there's no way to decide if the remaining data is an incomplete but otherwise /// valid UTF-8 char or just plain invalid UTF-8. /// (Issue [`rust-lang/rust#32584`][issue]) /// /// [errorkind]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html /// [`io::Error`]: https://doc.rust-lang.org/nightly/std/io/struct.Error.html /// [issue]: https://github.com/rust-lang/rust/issues/32584 fn chars(self) -> Chars<Self> where Self: Sized { Chars::new(self) } } #[cfg(test)] mod tests { use std::io; use br; use {Read, BufRead, BufReadGrow}; #[test] fn read_until() { let mut buf = io::Cursor::new(&b"12"[..]); let mut v = Vec::new(); assert_eq!(buf.read_until(b'3', &mut v).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(v, b"12"); let mut buf = io::Cursor::new(&b"1233"[..]); let mut v = Vec::new(); buf.read_until(b'3', &mut v).unwrap(); assert_eq!(v, b"123"); v.truncate(0); buf.read_until(b'3', &mut v).unwrap(); assert_eq!(v, b"3"); v.truncate(0); assert_eq!(buf.read_until(b'3', &mut v).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(v, b""); } #[test] fn read_to_end() { let mut c = io::Cursor::new(&b""[..]); let mut v = Vec::new(); c.read_to_end(&mut v).unwrap(); assert_eq!(v, b""); let mut c = io::Cursor::new(&b"1"[..]); let mut v = Vec::new(); c.read_to_end(&mut v).unwrap(); assert_eq!(v, b"1"); let cap = 1024 * 1024; let data = (0..cap).map(|i| (i / 3) as u8).collect::<Vec<_>>(); let mut v = Vec::new(); let (a, b) = data.split_at(data.len() / 2); io::Cursor::new(a).read_to_end(&mut v).unwrap(); io::Cursor::new(b).read_to_end(&mut v).unwrap(); assert_eq!(v, data); } #[test] fn read_to_string() { let mut c = io::Cursor::new(&b""[..]); let mut v = String::new(); c.read_to_string(&mut v).unwrap(); assert_eq!(v, ""); let mut c = io::Cursor::new(&b"1"[..]); let mut v = String::new(); c.read_to_string(&mut v).unwrap(); assert_eq!(v, "1"); let mut c = io::Cursor::new(&b"\xff"[..]); let mut v = String::new(); assert!(c.read_to_string(&mut v).is_err()); } #[test] fn read_exact() { let mut buf = [0; 4]; let mut buf = io::Cursor::new(&mut buf[..]); let mut c = io::Cursor::new(&b""[..]); assert_eq!(c.read_exact(&mut buf).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(buf.position(), 0); let mut c = io::Cursor::new(&b"123"[..]).chain(io::Cursor::new(&b"456789"[..])); buf.set_position(0); c.read_exact(&mut buf).unwrap(); assert_eq!(buf.position(), 4); assert_eq!(buf.get_ref(), b"1234"); buf.set_position(0); c.read_exact(&mut buf).unwrap(); assert_eq!(buf.position(), 4); assert_eq!(buf.get_ref(), b"5678"); buf.set_position(0); assert_eq!(c.read_exact(&mut buf).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(buf.position(), 1); } #[test] fn read_exact_slice() { let mut buf = [0; 4]; let mut buf = io::Cursor::new(&mut buf[..]); let mut c = &b""[..]; assert_eq!(c.read_exact(&mut buf).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); let mut c = &b"123"[..]; buf.set_position(0); assert_eq!(c.read_exact(&mut buf).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(buf.position(), 3); assert_eq!(buf.get_ref(), b"123\0"); let mut c = &b"1234"[..]; buf.set_position(0); c.read_exact(&mut buf).unwrap(); assert_eq!(buf.position(), 4); assert_eq!(buf.get_ref(), b"1234"); let mut c = &b"56789"[..]; buf.set_position(0); c.read_exact(&mut buf).unwrap(); assert_eq!(buf.position(), 4); assert_eq!(buf.get_ref(), b"5678"); assert_eq!(c, b"9"); } #[test] fn read_until2() { let mut buf = io::Cursor::new(&b"1234321234554"[..]); let mut v = Vec::new(); assert_eq!(buf.read_until2((b'3', b'5'), &mut v).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(v, b"1234321234554"); let mut buf = io::Cursor::new(&b"1234321234554"[..]); let mut v = Vec::new(); buf.read_until2((b'3', b'4'), &mut v).unwrap(); assert_eq!(v, b"1234"); v.truncate(0); buf.read_until2((b'3', b'4'), &mut v).unwrap(); assert_eq!(v, b"321234"); v.truncate(0); assert_eq!(buf.read_until2((b'3', b'4'), &mut v).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(v, b"554"); } #[test] fn read_until2_smallbuffer() { let mut buf = br::BufReader::with_capacity(3, io::Cursor::new(&b"12343212334554"[..])); let mut v = Vec::new(); assert_eq!(buf.read_until2((b'3', b'5'), &mut v).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(v, b"12343212334554"); let mut buf = br::BufReader::with_capacity(3, io::Cursor::new(&b"12343212334554"[..])); let mut v = Vec::new(); buf.read_until2((b'3', b'4'), &mut v).unwrap(); assert_eq!(v, b"1234"); v.truncate(0); buf.read_until2((b'3', b'4'), &mut v).unwrap(); assert_eq!(v, b"3212334"); v.truncate(0); assert_eq!(buf.read_until2((b'3', b'4'), &mut v).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(v, b"554"); } #[test] fn read_line() { let mut buf = io::Cursor::new(&b"hihi\r\nhoho\rhaha\nhehe\n\rhrhr\r\n\r\r\n\r\n"[..]); let mut v = String::new(); buf.read_line(&mut v).unwrap(); assert_eq!(v, "hihi\r\n"); v.truncate(0); buf.read_line(&mut v).unwrap(); assert_eq!(v, "hoho\rhaha\nhehe\n\rhrhr\r\n"); v.truncate(0); buf.read_line(&mut v).unwrap(); assert_eq!(v, "\r\r\n"); v.truncate(0); buf.read_line(&mut v).unwrap(); assert_eq!(v, "\r\n"); v.truncate(0); assert_eq!(buf.read_line(&mut v).unwrap_err().kind(), io::ErrorKind::UnexpectedEof); assert_eq!(v, ""); } #[test] fn fill_buf_str_unexpected_eof() { // Needs continuation character let testdata = [b'A', 0xC0]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::UnexpectedEof); // Needs continuation character let testdata = [b'A', 0xE0]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::UnexpectedEof); // Needs continuation character let testdata = [b'A', 0xE0, 0x80]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::UnexpectedEof); // Needs continuation character let testdata = [b'A', 0xF0]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::UnexpectedEof); // Needs continuation character let testdata = [b'A', 0xF0, 0x80]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::UnexpectedEof); // Needs continuation character let testdata = [b'A', 0xF0, 0x80, 0x80]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::UnexpectedEof); } #[test] fn fill_buf_str_invalid_data() { // cannot start with continuation character let testdata = [b'A', 0x80]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // cannot start with continuation characters let testdata = [b'A', 0x80, 0x80]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // cannot start with continuation characters let testdata = [b'A', 0x80, 0x80, 0x80]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // cannot start with continuation characters let testdata = [b'A', 0x80, 0x80, 0x80, 0x80]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // cannot start with continuation characters let testdata = [b'A', 0x80, 0x80, 0x80, 0x80, 0x80]; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xC0, b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xC0, b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xC0, b'A', b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xC0, b'A', b'A', b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xE0, b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xE0, b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xE0, b'A', b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xE0, b'A', b'A', b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xF0, b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xF0, b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xF0, b'A', b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); testdata.fill_buf_str().unwrap_err(); //assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); // Invalid continuation character let testdata = [b'A', 0xF0, b'A', b'A', b'A', b'A']; let mut testdata = io::Cursor::new(testdata); assert_eq!(testdata.fill_buf_str().unwrap(), "A"); testdata.consume(1); assert_eq!(testdata.fill_buf_str().unwrap_err().kind(), io::ErrorKind::InvalidData); } }