1 // Copyright 2013 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // ignore-lexer-test FIXME #15679
13 //! Readers and Writers for in-memory buffers
16 use option::Option::None;
17 use result::Result::{Err, Ok};
19 use old_io::{Reader, Writer, Seek, Buffer, IoError, SeekStyle, IoResult};
20 use slice::{self, AsSlice, SliceExt};
23 const BUF_CAPACITY: uint = 128;
25 fn combine(seek: SeekStyle, cur: uint, end: uint, offset: i64) -> IoResult<u64> {
26 // compute offset as signed and clamp to prevent overflow
27 let pos = match seek {
29 old_io::SeekEnd => end,
30 old_io::SeekCur => cur,
35 kind: old_io::InvalidInput,
36 desc: "invalid seek to a negative offset",
40 Ok((offset + pos) as u64)
44 impl Writer for Vec<u8> {
46 fn write_all(&mut self, buf: &[u8]) -> IoResult<()> {
52 /// Writes to an owned, growable byte vector
57 /// # #![allow(unused_must_use)]
58 /// use std::old_io::MemWriter;
60 /// let mut w = MemWriter::new();
61 /// w.write(&[0, 1, 2]);
63 /// assert_eq!(w.into_inner(), vec!(0, 1, 2));
65 #[unstable(feature = "io")]
66 #[deprecated(since = "1.0.0",
67 reason = "use the Vec<u8> Writer implementation directly")]
69 pub struct MemWriter {
75 /// Create a new `MemWriter`.
77 pub fn new() -> MemWriter {
78 MemWriter::with_capacity(BUF_CAPACITY)
80 /// Create a new `MemWriter`, allocating at least `n` bytes for
81 /// the internal buffer.
83 pub fn with_capacity(n: uint) -> MemWriter {
84 MemWriter::from_vec(Vec::with_capacity(n))
86 /// Create a new `MemWriter` that will append to an existing `Vec`.
88 pub fn from_vec(buf: Vec<u8>) -> MemWriter {
89 MemWriter { buf: buf }
92 /// Acquires an immutable reference to the underlying buffer of this
95 pub fn get_ref<'a>(&'a self) -> &'a [u8] { self.buf.as_slice() }
97 /// Unwraps this `MemWriter`, returning the underlying buffer
99 pub fn into_inner(self) -> Vec<u8> { self.buf }
102 impl Writer for MemWriter {
104 fn write_all(&mut self, buf: &[u8]) -> IoResult<()> {
105 self.buf.push_all(buf);
110 /// Reads from an owned byte vector
115 /// # #![allow(unused_must_use)]
116 /// use std::old_io::MemReader;
118 /// let mut r = MemReader::new(vec!(0, 1, 2));
120 /// assert_eq!(r.read_to_end().unwrap(), vec!(0, 1, 2));
122 pub struct MemReader {
128 /// Creates a new `MemReader` which will read the buffer given. The buffer
129 /// can be re-acquired through `unwrap`
131 pub fn new(buf: Vec<u8>) -> MemReader {
138 /// Tests whether this reader has read all bytes in its buffer.
140 /// If `true`, then this will no longer return bytes from `read`.
142 pub fn eof(&self) -> bool { self.pos >= self.buf.len() }
144 /// Acquires an immutable reference to the underlying buffer of this
147 /// No method is exposed for acquiring a mutable reference to the buffer
148 /// because it could corrupt the state of this `MemReader`.
150 pub fn get_ref<'a>(&'a self) -> &'a [u8] { self.buf.as_slice() }
152 /// Unwraps this `MemReader`, returning the underlying buffer
154 pub fn into_inner(self) -> Vec<u8> { self.buf }
157 impl Reader for MemReader {
159 fn read(&mut self, buf: &mut [u8]) -> IoResult<uint> {
160 if self.eof() { return Err(old_io::standard_error(old_io::EndOfFile)) }
162 let write_len = min(buf.len(), self.buf.len() - self.pos);
164 let input = &self.buf[self.pos.. self.pos + write_len];
165 let output = &mut buf[..write_len];
166 assert_eq!(input.len(), output.len());
167 slice::bytes::copy_memory(output, input);
169 self.pos += write_len;
170 assert!(self.pos <= self.buf.len());
172 return Ok(write_len);
176 impl Seek for MemReader {
178 fn tell(&self) -> IoResult<u64> { Ok(self.pos as u64) }
181 fn seek(&mut self, pos: i64, style: SeekStyle) -> IoResult<()> {
182 let new = try!(combine(style, self.pos, self.buf.len(), pos));
183 self.pos = new as uint;
188 impl Buffer for MemReader {
190 fn fill_buf<'a>(&'a mut self) -> IoResult<&'a [u8]> {
191 if self.pos < self.buf.len() {
192 Ok(&self.buf[self.pos..])
194 Err(old_io::standard_error(old_io::EndOfFile))
199 fn consume(&mut self, amt: uint) { self.pos += amt; }
202 impl<'a> Reader for &'a [u8] {
204 fn read(&mut self, buf: &mut [u8]) -> IoResult<uint> {
205 if self.is_empty() { return Err(old_io::standard_error(old_io::EndOfFile)); }
207 let write_len = min(buf.len(), self.len());
209 let input = &self[..write_len];
210 let output = &mut buf[.. write_len];
211 slice::bytes::copy_memory(output, input);
214 *self = &self[write_len..];
220 impl<'a> Buffer for &'a [u8] {
222 fn fill_buf(&mut self) -> IoResult<&[u8]> {
224 Err(old_io::standard_error(old_io::EndOfFile))
231 fn consume(&mut self, amt: uint) {
232 *self = &self[amt..];
237 /// Writes to a fixed-size byte slice
239 /// If a write will not fit in the buffer, it returns an error and does not
245 /// # #![allow(unused_must_use)]
246 /// use std::old_io::BufWriter;
248 /// let mut buf = [0; 4];
250 /// let mut w = BufWriter::new(&mut buf);
251 /// w.write(&[0, 1, 2]);
253 /// assert!(buf == [0, 1, 2, 0]);
255 pub struct BufWriter<'a> {
260 impl<'a> BufWriter<'a> {
261 /// Creates a new `BufWriter` which will wrap the specified buffer. The
262 /// writer initially starts at position 0.
264 pub fn new(buf: &'a mut [u8]) -> BufWriter<'a> {
272 impl<'a> Writer for BufWriter<'a> {
274 fn write_all(&mut self, src: &[u8]) -> IoResult<()> {
275 let dst = &mut self.buf[self.pos..];
276 let dst_len = dst.len();
279 return Err(old_io::standard_error(old_io::EndOfFile));
282 let src_len = src.len();
284 if dst_len >= src_len {
285 slice::bytes::copy_memory(dst, src);
291 slice::bytes::copy_memory(dst, &src[..dst_len]);
295 Err(old_io::standard_error(old_io::ShortWrite(dst_len)))
300 impl<'a> Seek for BufWriter<'a> {
302 fn tell(&self) -> IoResult<u64> { Ok(self.pos as u64) }
305 fn seek(&mut self, pos: i64, style: SeekStyle) -> IoResult<()> {
306 let new = try!(combine(style, self.pos, self.buf.len(), pos));
307 self.pos = min(new as uint, self.buf.len());
312 /// Reads from a fixed-size byte slice
317 /// # #![allow(unused_must_use)]
318 /// use std::old_io::BufReader;
320 /// let buf = [0, 1, 2, 3];
321 /// let mut r = BufReader::new(&buf);
323 /// assert_eq!(r.read_to_end().unwrap(), vec![0, 1, 2, 3]);
325 pub struct BufReader<'a> {
330 impl<'a> BufReader<'a> {
331 /// Creates a new buffered reader which will read the specified buffer
333 pub fn new(buf: &'a [u8]) -> BufReader<'a> {
340 /// Tests whether this reader has read all bytes in its buffer.
342 /// If `true`, then this will no longer return bytes from `read`.
344 pub fn eof(&self) -> bool { self.pos >= self.buf.len() }
347 impl<'a> Reader for BufReader<'a> {
349 fn read(&mut self, buf: &mut [u8]) -> IoResult<uint> {
350 if self.eof() { return Err(old_io::standard_error(old_io::EndOfFile)) }
352 let write_len = min(buf.len(), self.buf.len() - self.pos);
354 let input = &self.buf[self.pos.. self.pos + write_len];
355 let output = &mut buf[..write_len];
356 assert_eq!(input.len(), output.len());
357 slice::bytes::copy_memory(output, input);
359 self.pos += write_len;
360 assert!(self.pos <= self.buf.len());
362 return Ok(write_len);
366 impl<'a> Seek for BufReader<'a> {
368 fn tell(&self) -> IoResult<u64> { Ok(self.pos as u64) }
371 fn seek(&mut self, pos: i64, style: SeekStyle) -> IoResult<()> {
372 let new = try!(combine(style, self.pos, self.buf.len(), pos));
373 self.pos = new as uint;
378 impl<'a> Buffer for BufReader<'a> {
380 fn fill_buf(&mut self) -> IoResult<&[u8]> {
381 if self.pos < self.buf.len() {
382 Ok(&self.buf[self.pos..])
384 Err(old_io::standard_error(old_io::EndOfFile))
389 fn consume(&mut self, amt: uint) { self.pos += amt; }
394 extern crate "test" as test_crate;
395 use old_io::{SeekSet, SeekCur, SeekEnd, Reader, Writer, Seek};
396 use prelude::v1::{Ok, Err, range, Vec, Buffer, AsSlice, SliceExt};
397 use prelude::v1::IteratorExt;
400 use self::test_crate::Bencher;
404 fn test_vec_writer() {
405 let mut writer = Vec::new();
406 writer.write(&[0]).unwrap();
407 writer.write(&[1, 2, 3]).unwrap();
408 writer.write(&[4, 5, 6, 7]).unwrap();
409 let b: &[_] = &[0, 1, 2, 3, 4, 5, 6, 7];
410 assert_eq!(writer.as_slice(), b);
414 fn test_mem_writer() {
415 let mut writer = MemWriter::new();
416 writer.write(&[0]).unwrap();
417 writer.write(&[1, 2, 3]).unwrap();
418 writer.write(&[4, 5, 6, 7]).unwrap();
419 let b: &[_] = &[0, 1, 2, 3, 4, 5, 6, 7];
420 assert_eq!(writer.get_ref(), b);
424 fn test_buf_writer() {
425 let mut buf = [0 as u8; 9];
427 let mut writer = BufWriter::new(&mut buf);
428 assert_eq!(writer.tell(), Ok(0));
429 writer.write(&[0]).unwrap();
430 assert_eq!(writer.tell(), Ok(1));
431 writer.write(&[1, 2, 3]).unwrap();
432 writer.write(&[4, 5, 6, 7]).unwrap();
433 assert_eq!(writer.tell(), Ok(8));
434 writer.write(&[]).unwrap();
435 assert_eq!(writer.tell(), Ok(8));
437 assert_eq!(writer.write(&[8, 9]).err().unwrap().kind, old_io::ShortWrite(1));
438 assert_eq!(writer.write(&[10]).err().unwrap().kind, old_io::EndOfFile);
440 let b: &[_] = &[0, 1, 2, 3, 4, 5, 6, 7, 8];
445 fn test_buf_writer_seek() {
446 let mut buf = [0 as u8; 8];
448 let mut writer = BufWriter::new(&mut buf);
449 assert_eq!(writer.tell(), Ok(0));
450 writer.write(&[1]).unwrap();
451 assert_eq!(writer.tell(), Ok(1));
453 writer.seek(2, SeekSet).unwrap();
454 assert_eq!(writer.tell(), Ok(2));
455 writer.write(&[2]).unwrap();
456 assert_eq!(writer.tell(), Ok(3));
458 writer.seek(-2, SeekCur).unwrap();
459 assert_eq!(writer.tell(), Ok(1));
460 writer.write(&[3]).unwrap();
461 assert_eq!(writer.tell(), Ok(2));
463 writer.seek(-1, SeekEnd).unwrap();
464 assert_eq!(writer.tell(), Ok(7));
465 writer.write(&[4]).unwrap();
466 assert_eq!(writer.tell(), Ok(8));
469 let b: &[_] = &[1, 3, 2, 0, 0, 0, 0, 4];
474 fn test_buf_writer_error() {
475 let mut buf = [0 as u8; 2];
476 let mut writer = BufWriter::new(&mut buf);
477 writer.write(&[0]).unwrap();
479 match writer.write(&[0, 0]) {
481 Err(e) => assert_eq!(e.kind, old_io::ShortWrite(1)),
486 fn test_mem_reader() {
487 let mut reader = MemReader::new(vec!(0, 1, 2, 3, 4, 5, 6, 7));
489 assert_eq!(reader.read(&mut buf), Ok(0));
490 assert_eq!(reader.tell(), Ok(0));
492 assert_eq!(reader.read(&mut buf), Ok(1));
493 assert_eq!(reader.tell(), Ok(1));
496 let mut buf = [0; 4];
497 assert_eq!(reader.read(&mut buf), Ok(4));
498 assert_eq!(reader.tell(), Ok(5));
499 let b: &[_] = &[1, 2, 3, 4];
501 assert_eq!(reader.read(&mut buf), Ok(3));
502 let b: &[_] = &[5, 6, 7];
503 assert_eq!(&buf[..3], b);
504 assert!(reader.read(&mut buf).is_err());
505 let mut reader = MemReader::new(vec!(0, 1, 2, 3, 4, 5, 6, 7));
506 assert_eq!(reader.read_until(3).unwrap(), vec!(0, 1, 2, 3));
507 assert_eq!(reader.read_until(3).unwrap(), vec!(4, 5, 6, 7));
508 assert!(reader.read(&mut buf).is_err());
512 fn test_slice_reader() {
513 let in_buf = vec![0, 1, 2, 3, 4, 5, 6, 7];
514 let mut reader = &mut in_buf.as_slice();
516 assert_eq!(reader.read(&mut buf), Ok(0));
518 assert_eq!(reader.read(&mut buf), Ok(1));
519 assert_eq!(reader.len(), 7);
521 assert_eq!(buf.as_slice(), b);
522 let mut buf = [0; 4];
523 assert_eq!(reader.read(&mut buf), Ok(4));
524 assert_eq!(reader.len(), 3);
525 let b: &[_] = &[1, 2, 3, 4];
526 assert_eq!(buf.as_slice(), b);
527 assert_eq!(reader.read(&mut buf), Ok(3));
528 let b: &[_] = &[5, 6, 7];
529 assert_eq!(&buf[..3], b);
530 assert!(reader.read(&mut buf).is_err());
531 let mut reader = &mut in_buf.as_slice();
532 assert_eq!(reader.read_until(3).unwrap(), vec!(0, 1, 2, 3));
533 assert_eq!(reader.read_until(3).unwrap(), vec!(4, 5, 6, 7));
534 assert!(reader.read(&mut buf).is_err());
538 fn test_buf_reader() {
539 let in_buf = vec![0, 1, 2, 3, 4, 5, 6, 7];
540 let mut reader = BufReader::new(in_buf.as_slice());
542 assert_eq!(reader.read(&mut buf), Ok(0));
543 assert_eq!(reader.tell(), Ok(0));
545 assert_eq!(reader.read(&mut buf), Ok(1));
546 assert_eq!(reader.tell(), Ok(1));
549 let mut buf = [0; 4];
550 assert_eq!(reader.read(&mut buf), Ok(4));
551 assert_eq!(reader.tell(), Ok(5));
552 let b: &[_] = &[1, 2, 3, 4];
554 assert_eq!(reader.read(&mut buf), Ok(3));
555 let b: &[_] = &[5, 6, 7];
556 assert_eq!(&buf[..3], b);
557 assert!(reader.read(&mut buf).is_err());
558 let mut reader = BufReader::new(in_buf.as_slice());
559 assert_eq!(reader.read_until(3).unwrap(), vec!(0, 1, 2, 3));
560 assert_eq!(reader.read_until(3).unwrap(), vec!(4, 5, 6, 7));
561 assert!(reader.read(&mut buf).is_err());
565 fn test_read_char() {
566 let b = b"Vi\xE1\xBB\x87t";
567 let mut r = BufReader::new(b);
568 assert_eq!(r.read_char(), Ok('V'));
569 assert_eq!(r.read_char(), Ok('i'));
570 assert_eq!(r.read_char(), Ok('ệ'));
571 assert_eq!(r.read_char(), Ok('t'));
572 assert!(r.read_char().is_err());
576 fn test_read_bad_char() {
578 let mut r = BufReader::new(b);
579 assert!(r.read_char().is_err());
583 fn test_write_strings() {
584 let mut writer = MemWriter::new();
585 writer.write_str("testing").unwrap();
586 writer.write_line("testing").unwrap();
587 writer.write_str("testing").unwrap();
588 let mut r = BufReader::new(writer.get_ref());
589 assert_eq!(r.read_to_string().unwrap(), "testingtesting\ntesting");
593 fn test_write_char() {
594 let mut writer = MemWriter::new();
595 writer.write_char('a').unwrap();
596 writer.write_char('\n').unwrap();
597 writer.write_char('ệ').unwrap();
598 let mut r = BufReader::new(writer.get_ref());
599 assert_eq!(r.read_to_string().unwrap(), "a\nệ");
603 fn test_read_whole_string_bad() {
605 let mut r = BufReader::new(&buf);
606 match r.read_to_string() {
615 let mut r = BufReader::new(&buf);
616 r.seek(10, SeekSet).unwrap();
617 assert!(r.read(&mut []).is_err());
619 let mut r = MemReader::new(vec!(10));
620 r.seek(10, SeekSet).unwrap();
621 assert!(r.read(&mut []).is_err());
624 let mut r = BufWriter::new(&mut buf);
625 r.seek(10, SeekSet).unwrap();
626 assert!(r.write(&[3]).is_err());
632 let mut r = BufReader::new(&buf);
633 assert!(r.seek(-1, SeekSet).is_err());
635 let mut r = MemReader::new(vec!(10));
636 assert!(r.seek(-1, SeekSet).is_err());
639 let mut r = BufWriter::new(&mut buf);
640 assert!(r.seek(-1, SeekSet).is_err());
644 fn io_read_at_least() {
645 let mut r = MemReader::new(vec![1, 2, 3, 4, 5, 6, 7, 8]);
646 let mut buf = [0; 3];
647 assert!(r.read_at_least(buf.len(), &mut buf).is_ok());
648 let b: &[_] = &[1, 2, 3];
650 assert!(r.read_at_least(0, &mut buf[..0]).is_ok());
652 assert!(r.read_at_least(buf.len(), &mut buf).is_ok());
653 let b: &[_] = &[4, 5, 6];
655 assert!(r.read_at_least(buf.len(), &mut buf).is_err());
656 let b: &[_] = &[7, 8, 6];
660 fn do_bench_mem_writer(b: &mut Bencher, times: uint, len: uint) {
661 let src: Vec<u8> = repeat(5).take(len).collect();
663 b.bytes = (times * len) as u64;
665 let mut wr = MemWriter::new();
667 wr.write(src.as_slice()).unwrap();
670 let v = wr.into_inner();
671 assert_eq!(v.len(), times * len);
672 assert!(v.iter().all(|x| *x == 5));
677 fn bench_mem_writer_001_0000(b: &mut Bencher) {
678 do_bench_mem_writer(b, 1, 0)
682 fn bench_mem_writer_001_0010(b: &mut Bencher) {
683 do_bench_mem_writer(b, 1, 10)
687 fn bench_mem_writer_001_0100(b: &mut Bencher) {
688 do_bench_mem_writer(b, 1, 100)
692 fn bench_mem_writer_001_1000(b: &mut Bencher) {
693 do_bench_mem_writer(b, 1, 1000)
697 fn bench_mem_writer_100_0000(b: &mut Bencher) {
698 do_bench_mem_writer(b, 100, 0)
702 fn bench_mem_writer_100_0010(b: &mut Bencher) {
703 do_bench_mem_writer(b, 100, 10)
707 fn bench_mem_writer_100_0100(b: &mut Bencher) {
708 do_bench_mem_writer(b, 100, 100)
712 fn bench_mem_writer_100_1000(b: &mut Bencher) {
713 do_bench_mem_writer(b, 100, 1000)
717 fn bench_mem_reader(b: &mut Bencher) {
719 let buf = [5 as u8; 100].to_vec();
721 let mut rdr = MemReader::new(buf);
723 let mut buf = [0 as u8; 10];
724 rdr.read(&mut buf).unwrap();
725 assert_eq!(buf.as_slice(), [5; 10].as_slice());
732 fn bench_buf_writer(b: &mut Bencher) {
734 let mut buf = [0 as u8; 100];
736 let mut wr = BufWriter::new(&mut buf);
738 wr.write(&[5; 10]).unwrap();
741 assert_eq!(buf.as_slice(), [5; 100].as_slice());
746 fn bench_buf_reader(b: &mut Bencher) {
748 let buf = [5 as u8; 100];
750 let mut rdr = BufReader::new(&buf);
752 let mut buf = [0 as u8; 10];
753 rdr.read(&mut buf).unwrap();
754 assert_eq!(buf, [5; 10]);