--- /dev/null
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you 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 std::cmp;
+use std::io;
+use std::io::{Read, Write};
+
+use super::{TReadTransport, TReadTransportFactory, TWriteTransport, TWriteTransportFactory};
+
+/// Default capacity of the read buffer in bytes.
+const READ_CAPACITY: usize = 4096;
+
+/// Default capacity of the write buffer in bytes..
+const WRITE_CAPACITY: usize = 4096;
+
+/// Transport that reads messages via an internal buffer.
+///
+/// A `TBufferedReadTransport` maintains a fixed-size internal read buffer.
+/// On a call to `TBufferedReadTransport::read(...)` one full message - both
+/// fixed-length header and bytes - is read from the wrapped channel and buffered.
+/// Subsequent read calls are serviced from the internal buffer until it is
+/// exhausted, at which point the next full message is read from the wrapped
+/// channel.
+///
+/// # Examples
+///
+/// Create and use a `TBufferedReadTransport`.
+///
+/// ```no_run
+/// use std::io::Read;
+/// use thrift::transport::{TBufferedReadTransport, TTcpChannel};
+///
+/// let mut c = TTcpChannel::new();
+/// c.open("localhost:9090").unwrap();
+///
+/// let mut t = TBufferedReadTransport::new(c);
+///
+/// t.read(&mut vec![0u8; 1]).unwrap();
+/// ```
+#[derive(Debug)]
+pub struct TBufferedReadTransport<C>
+where
+ C: Read,
+{
+ buf: Box<[u8]>,
+ pos: usize,
+ cap: usize,
+ chan: C,
+}
+
+impl<C> TBufferedReadTransport<C>
+where
+ C: Read,
+{
+ /// Create a `TBufferedTransport` with default-sized internal read and
+ /// write buffers that wraps the given `TIoChannel`.
+ pub fn new(channel: C) -> TBufferedReadTransport<C> {
+ TBufferedReadTransport::with_capacity(READ_CAPACITY, channel)
+ }
+
+ /// Create a `TBufferedTransport` with an internal read buffer of size
+ /// `read_capacity` and an internal write buffer of size
+ /// `write_capacity` that wraps the given `TIoChannel`.
+ pub fn with_capacity(read_capacity: usize, channel: C) -> TBufferedReadTransport<C> {
+ TBufferedReadTransport {
+ buf: vec![0; read_capacity].into_boxed_slice(),
+ pos: 0,
+ cap: 0,
+ chan: channel,
+ }
+ }
+
+ fn get_bytes(&mut self) -> io::Result<&[u8]> {
+ if self.cap - self.pos == 0 {
+ self.pos = 0;
+ self.cap = self.chan.read(&mut self.buf)?;
+ }
+
+ Ok(&self.buf[self.pos..self.cap])
+ }
+
+ fn consume(&mut self, consumed: usize) {
+ // TODO: was a bug here += <-- test somehow
+ self.pos = cmp::min(self.cap, self.pos + consumed);
+ }
+}
+
+impl<C> Read for TBufferedReadTransport<C>
+where
+ C: Read,
+{
+ fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+ let mut bytes_read = 0;
+
+ loop {
+ let nread = {
+ let avail_bytes = self.get_bytes()?;
+ let avail_space = buf.len() - bytes_read;
+ let nread = cmp::min(avail_space, avail_bytes.len());
+ buf[bytes_read..(bytes_read + nread)].copy_from_slice(&avail_bytes[..nread]);
+ nread
+ };
+
+ self.consume(nread);
+ bytes_read += nread;
+
+ if bytes_read == buf.len() || nread == 0 {
+ break;
+ }
+ }
+
+ Ok(bytes_read)
+ }
+}
+
+/// Factory for creating instances of `TBufferedReadTransport`.
+#[derive(Default)]
+pub struct TBufferedReadTransportFactory;
+
+impl TBufferedReadTransportFactory {
+ pub fn new() -> TBufferedReadTransportFactory {
+ TBufferedReadTransportFactory {}
+ }
+}
+
+impl TReadTransportFactory for TBufferedReadTransportFactory {
+ /// Create a `TBufferedReadTransport`.
+ fn create(&self, channel: Box<dyn Read + Send>) -> Box<dyn TReadTransport + Send> {
+ Box::new(TBufferedReadTransport::new(channel))
+ }
+}
+
+/// Transport that writes messages via an internal buffer.
+///
+/// A `TBufferedWriteTransport` maintains a fixed-size internal write buffer.
+/// All writes are made to this buffer and are sent to the wrapped channel only
+/// when `TBufferedWriteTransport::flush()` is called. On a flush a fixed-length
+/// header with a count of the buffered bytes is written, followed by the bytes
+/// themselves.
+///
+/// # Examples
+///
+/// Create and use a `TBufferedWriteTransport`.
+///
+/// ```no_run
+/// use std::io::Write;
+/// use thrift::transport::{TBufferedWriteTransport, TTcpChannel};
+///
+/// let mut c = TTcpChannel::new();
+/// c.open("localhost:9090").unwrap();
+///
+/// let mut t = TBufferedWriteTransport::new(c);
+///
+/// t.write(&[0x00]).unwrap();
+/// t.flush().unwrap();
+/// ```
+#[derive(Debug)]
+pub struct TBufferedWriteTransport<C>
+where
+ C: Write,
+{
+ buf: Vec<u8>,
+ cap: usize,
+ channel: C,
+}
+
+impl<C> TBufferedWriteTransport<C>
+where
+ C: Write,
+{
+ /// Create a `TBufferedTransport` with default-sized internal read and
+ /// write buffers that wraps the given `TIoChannel`.
+ pub fn new(channel: C) -> TBufferedWriteTransport<C> {
+ TBufferedWriteTransport::with_capacity(WRITE_CAPACITY, channel)
+ }
+
+ /// Create a `TBufferedTransport` with an internal read buffer of size
+ /// `read_capacity` and an internal write buffer of size
+ /// `write_capacity` that wraps the given `TIoChannel`.
+ pub fn with_capacity(write_capacity: usize, channel: C) -> TBufferedWriteTransport<C> {
+ assert!(
+ write_capacity > 0,
+ "write buffer size must be a positive integer"
+ );
+
+ TBufferedWriteTransport {
+ buf: Vec::with_capacity(write_capacity),
+ cap: write_capacity,
+ channel: channel,
+ }
+ }
+}
+
+impl<C> Write for TBufferedWriteTransport<C>
+where
+ C: Write,
+{
+ fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+ if !buf.is_empty() {
+ let mut avail_bytes;
+
+ loop {
+ avail_bytes = cmp::min(buf.len(), self.cap - self.buf.len());
+
+ if avail_bytes == 0 {
+ self.flush()?;
+ } else {
+ break;
+ }
+ }
+
+ let avail_bytes = avail_bytes;
+
+ self.buf.extend_from_slice(&buf[..avail_bytes]);
+ assert!(self.buf.len() <= self.cap, "copy overflowed buffer");
+
+ Ok(avail_bytes)
+ } else {
+ Ok(0)
+ }
+ }
+
+ fn flush(&mut self) -> io::Result<()> {
+ self.channel.write_all(&self.buf)?;
+ self.channel.flush()?;
+ self.buf.clear();
+ Ok(())
+ }
+}
+
+/// Factory for creating instances of `TBufferedWriteTransport`.
+#[derive(Default)]
+pub struct TBufferedWriteTransportFactory;
+
+impl TBufferedWriteTransportFactory {
+ pub fn new() -> TBufferedWriteTransportFactory {
+ TBufferedWriteTransportFactory {}
+ }
+}
+
+impl TWriteTransportFactory for TBufferedWriteTransportFactory {
+ /// Create a `TBufferedWriteTransport`.
+ fn create(&self, channel: Box<dyn Write + Send>) -> Box<dyn TWriteTransport + Send> {
+ Box::new(TBufferedWriteTransport::new(channel))
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use std::io::{Read, Write};
+
+ use super::*;
+ use transport::TBufferChannel;
+
+ #[test]
+ fn must_return_zero_if_read_buffer_is_empty() {
+ let mem = TBufferChannel::with_capacity(10, 0);
+ let mut t = TBufferedReadTransport::with_capacity(10, mem);
+
+ let mut b = vec![0; 10];
+ let read_result = t.read(&mut b);
+
+ assert_eq!(read_result.unwrap(), 0);
+ }
+
+ #[test]
+ fn must_return_zero_if_caller_reads_into_zero_capacity_buffer() {
+ let mem = TBufferChannel::with_capacity(10, 0);
+ let mut t = TBufferedReadTransport::with_capacity(10, mem);
+
+ let read_result = t.read(&mut []);
+
+ assert_eq!(read_result.unwrap(), 0);
+ }
+
+ #[test]
+ fn must_return_zero_if_nothing_more_can_be_read() {
+ let mem = TBufferChannel::with_capacity(4, 0);
+ let mut t = TBufferedReadTransport::with_capacity(4, mem);
+
+ t.chan.set_readable_bytes(&[0, 1, 2, 3]);
+
+ // read buffer is exactly the same size as bytes available
+ let mut buf = vec![0u8; 4];
+ let read_result = t.read(&mut buf);
+
+ // we've read exactly 4 bytes
+ assert_eq!(read_result.unwrap(), 4);
+ assert_eq!(&buf, &[0, 1, 2, 3]);
+
+ // try read again
+ let buf_again = vec![0u8; 4];
+ let read_result = t.read(&mut buf);
+
+ // this time, 0 bytes and we haven't changed the buffer
+ assert_eq!(read_result.unwrap(), 0);
+ assert_eq!(&buf_again, &[0, 0, 0, 0])
+ }
+
+ #[test]
+ fn must_fill_user_buffer_with_only_as_many_bytes_as_available() {
+ let mem = TBufferChannel::with_capacity(4, 0);
+ let mut t = TBufferedReadTransport::with_capacity(4, mem);
+
+ t.chan.set_readable_bytes(&[0, 1, 2, 3]);
+
+ // read buffer is much larger than the bytes available
+ let mut buf = vec![0u8; 8];
+ let read_result = t.read(&mut buf);
+
+ // we've read exactly 4 bytes
+ assert_eq!(read_result.unwrap(), 4);
+ assert_eq!(&buf[..4], &[0, 1, 2, 3]);
+
+ // try read again
+ let read_result = t.read(&mut buf[4..]);
+
+ // this time, 0 bytes and we haven't changed the buffer
+ assert_eq!(read_result.unwrap(), 0);
+ assert_eq!(&buf, &[0, 1, 2, 3, 0, 0, 0, 0])
+ }
+
+ #[test]
+ fn must_read_successfully() {
+ // this test involves a few loops within the buffered transport
+ // itself where it has to drain the underlying transport in order
+ // to service a read
+
+ // we have a much smaller buffer than the
+ // underlying transport has bytes available
+ let mem = TBufferChannel::with_capacity(10, 0);
+ let mut t = TBufferedReadTransport::with_capacity(2, mem);
+
+ // fill the underlying transport's byte buffer
+ let mut readable_bytes = [0u8; 10];
+ for i in 0..10 {
+ readable_bytes[i] = i as u8;
+ }
+
+ t.chan.set_readable_bytes(&readable_bytes);
+
+ // we ask to read into a buffer that's much larger
+ // than the one the buffered transport has; as a result
+ // it's going to have to keep asking the underlying
+ // transport for more bytes
+ let mut buf = [0u8; 8];
+ let read_result = t.read(&mut buf);
+
+ // we should have read 8 bytes
+ assert_eq!(read_result.unwrap(), 8);
+ assert_eq!(&buf, &[0, 1, 2, 3, 4, 5, 6, 7]);
+
+ // let's clear out the buffer and try read again
+ for i in 0..8 {
+ buf[i] = 0;
+ }
+ let read_result = t.read(&mut buf);
+
+ // this time we were only able to read 2 bytes
+ // (all that's remaining from the underlying transport)
+ // let's also check that the remaining bytes are untouched
+ assert_eq!(read_result.unwrap(), 2);
+ assert_eq!(&buf[0..2], &[8, 9]);
+ assert_eq!(&buf[2..], &[0, 0, 0, 0, 0, 0]);
+
+ // try read again (we should get 0)
+ // and all the existing bytes were untouched
+ let read_result = t.read(&mut buf);
+ assert_eq!(read_result.unwrap(), 0);
+ assert_eq!(&buf[0..2], &[8, 9]);
+ assert_eq!(&buf[2..], &[0, 0, 0, 0, 0, 0]);
+ }
+
+ #[test]
+ fn must_return_error_when_nothing_can_be_written_to_underlying_channel() {
+ let mem = TBufferChannel::with_capacity(0, 0);
+ let mut t = TBufferedWriteTransport::with_capacity(1, mem);
+
+ let b = vec![0; 10];
+ let r = t.write(&b);
+
+ // should have written 1 byte
+ assert_eq!(r.unwrap(), 1);
+
+ // let's try again...
+ let r = t.write(&b[1..]);
+
+ // this time we'll error out because the auto-flush failed
+ assert!(r.is_err());
+ }
+
+ #[test]
+ fn must_return_zero_if_caller_calls_write_with_empty_buffer() {
+ let mem = TBufferChannel::with_capacity(0, 10);
+ let mut t = TBufferedWriteTransport::with_capacity(10, mem);
+
+ let r = t.write(&[]);
+ let expected: [u8; 0] = [];
+
+ assert_eq!(r.unwrap(), 0);
+ assert_eq_transport_written_bytes!(t, expected);
+ }
+
+ #[test]
+ fn must_auto_flush_if_write_buffer_full() {
+ let mem = TBufferChannel::with_capacity(0, 8);
+ let mut t = TBufferedWriteTransport::with_capacity(4, mem);
+
+ let b0 = [0x00, 0x01, 0x02, 0x03];
+ let b1 = [0x04, 0x05, 0x06, 0x07];
+
+ // write the first 4 bytes; we've now filled the transport's write buffer
+ let r = t.write(&b0);
+ assert_eq!(r.unwrap(), 4);
+
+ // try write the next 4 bytes; this causes the transport to auto-flush the first 4 bytes
+ let r = t.write(&b1);
+ assert_eq!(r.unwrap(), 4);
+
+ // check that in writing the second 4 bytes we auto-flushed the first 4 bytes
+ assert_eq_transport_num_written_bytes!(t, 4);
+ assert_eq_transport_written_bytes!(t, b0);
+ t.channel.empty_write_buffer();
+
+ // now flush the transport to push the second 4 bytes to the underlying channel
+ assert!(t.flush().is_ok());
+
+ // check that we wrote out the second 4 bytes
+ assert_eq_transport_written_bytes!(t, b1);
+ }
+
+ #[test]
+ fn must_write_to_inner_transport_on_flush() {
+ let mem = TBufferChannel::with_capacity(10, 10);
+ let mut t = TBufferedWriteTransport::new(mem);
+
+ let b: [u8; 5] = [0, 1, 2, 3, 4];
+ assert_eq!(t.write(&b).unwrap(), 5);
+ assert_eq_transport_num_written_bytes!(t, 0);
+
+ assert!(t.flush().is_ok());
+
+ assert_eq_transport_written_bytes!(t, b);
+ }
+
+ #[test]
+ fn must_write_successfully_after_flush() {
+ let mem = TBufferChannel::with_capacity(0, 5);
+ let mut t = TBufferedWriteTransport::with_capacity(5, mem);
+
+ // write and flush
+ let b: [u8; 5] = [0, 1, 2, 3, 4];
+ assert_eq!(t.write(&b).unwrap(), 5);
+ assert!(t.flush().is_ok());
+
+ // check the flushed bytes
+ assert_eq_transport_written_bytes!(t, b);
+
+ // reset our underlying transport
+ t.channel.empty_write_buffer();
+
+ // write and flush again
+ assert_eq!(t.write(&b).unwrap(), 5);
+ assert!(t.flush().is_ok());
+
+ // check the flushed bytes
+ assert_eq_transport_written_bytes!(t, b);
+ }
+}
projects / ceph.git / blobdiff