diff options
Diffstat (limited to 'grep-searcher/src/line_buffer.rs')
| -rw-r--r-- | grep-searcher/src/line_buffer.rs | 121 |
1 files changed, 43 insertions, 78 deletions
diff --git a/grep-searcher/src/line_buffer.rs b/grep-searcher/src/line_buffer.rs index 0f5a2a7a..5a969743 100644 --- a/grep-searcher/src/line_buffer.rs +++ b/grep-searcher/src/line_buffer.rs @@ -1,8 +1,7 @@ use std::cmp; use std::io; -use std::ptr; -use memchr::{memchr, memrchr}; +use bstr::{BStr, BString}; /// The default buffer capacity that we use for the line buffer. pub(crate) const DEFAULT_BUFFER_CAPACITY: usize = 8 * (1<<10); // 8 KB @@ -123,7 +122,7 @@ impl LineBufferBuilder { pub fn build(&self) -> LineBuffer { LineBuffer { config: self.config, - buf: vec![0; self.config.capacity], + buf: BString::from(vec![0; self.config.capacity]), pos: 0, last_lineterm: 0, end: 0, @@ -254,7 +253,7 @@ impl<'b, R: io::Read> LineBufferReader<'b, R> { } /// Return the contents of this buffer. - pub fn buffer(&self) -> &[u8] { + pub fn buffer(&self) -> &BStr { self.line_buffer.buffer() } @@ -284,7 +283,7 @@ pub struct LineBuffer { /// The configuration of this buffer. config: Config, /// The primary buffer with which to hold data. - buf: Vec<u8>, + buf: BString, /// The current position of this buffer. This is always a valid sliceable /// index into `buf`, and its maximum value is the length of `buf`. pos: usize, @@ -339,13 +338,13 @@ impl LineBuffer { } /// Return the contents of this buffer. - fn buffer(&self) -> &[u8] { + fn buffer(&self) -> &BStr { &self.buf[self.pos..self.last_lineterm] } /// Return the contents of the free space beyond the end of the buffer as /// a mutable slice. - fn free_buffer(&mut self) -> &mut [u8] { + fn free_buffer(&mut self) -> &mut BStr { &mut self.buf[self.end..] } @@ -396,7 +395,7 @@ impl LineBuffer { assert_eq!(self.pos, 0); loop { self.ensure_capacity()?; - let readlen = rdr.read(self.free_buffer())?; + let readlen = rdr.read(self.free_buffer().as_bytes_mut())?; if readlen == 0 { // We're only done reading for good once the caller has // consumed everything. @@ -416,7 +415,7 @@ impl LineBuffer { match self.config.binary { BinaryDetection::None => {} // nothing to do BinaryDetection::Quit(byte) => { - if let Some(i) = memchr(byte, newbytes) { + if let Some(i) = newbytes.find_byte(byte) { self.end = oldend + i; self.last_lineterm = self.end; self.binary_byte_offset = @@ -444,7 +443,7 @@ impl LineBuffer { } // Update our `last_lineterm` positions if we read one. - if let Some(i) = memrchr(self.config.lineterm, newbytes) { + if let Some(i) = newbytes.rfind_byte(self.config.lineterm) { self.last_lineterm = oldend + i + 1; return Ok(true); } @@ -467,40 +466,8 @@ impl LineBuffer { return; } - assert!(self.pos < self.end && self.end <= self.buf.len()); let roll_len = self.end - self.pos; - unsafe { - // SAFETY: A buffer contains Copy data, so there's no problem - // moving it around. Safety also depends on our indices being - // in bounds, which they should always be, and we enforce with - // an assert above. - // - // It seems like it should be possible to do this in safe code that - // results in the same codegen. I tried the obvious: - // - // for (src, dst) in (self.pos..self.end).zip(0..) { - // self.buf[dst] = self.buf[src]; - // } - // - // But the above does not work, and in fact compiles down to a slow - // byte-by-byte loop. I tried a few other minor variations, but - // alas, better minds might prevail. - // - // Overall, this doesn't save us *too* much. It mostly matters when - // the number of bytes we're copying is large, which can happen - // if the searcher is asked to produce a lot of context. We could - // decide this isn't worth it, but it does make an appreciable - // impact at or around the context=30 range on my machine. - // - // We could also use a temporary buffer that compiles down to two - // memcpys and is faster than the byte-at-a-time loop, but it - // complicates our options for limiting memory allocation a bit. - ptr::copy( - self.buf[self.pos..].as_ptr(), - self.buf.as_mut_ptr(), - roll_len, - ); - } + self.buf.copy_within(self.pos.., 0); self.pos = 0; self.last_lineterm = roll_len; self.end = roll_len; @@ -536,14 +503,15 @@ impl LineBuffer { } } -/// Replaces `src` with `replacement` in bytes. -fn replace_bytes(bytes: &mut [u8], src: u8, replacement: u8) -> Option<usize> { +/// Replaces `src` with `replacement` in bytes, and return the offset of the +/// first replacement, if one exists. +fn replace_bytes(bytes: &mut BStr, src: u8, replacement: u8) -> Option<usize> { if src == replacement { return None; } let mut first_pos = None; let mut pos = 0; - while let Some(i) = memchr(src, &bytes[pos..]).map(|i| pos + i) { + while let Some(i) = bytes[pos..].find_byte(src).map(|i| pos + i) { if first_pos.is_none() { first_pos = Some(i); } @@ -560,6 +528,7 @@ fn replace_bytes(bytes: &mut [u8], src: u8, replacement: u8) -> Option<usize> { #[cfg(test)] mod tests { use std::str; + use bstr::BString; use super::*; const SHERLOCK: &'static str = "\ @@ -575,18 +544,14 @@ and exhibited clearly, with a label attached.\ slice.to_string() } - fn btos(slice: &[u8]) -> &str { - str::from_utf8(slice).unwrap() - } - fn replace_str( slice: &str, src: u8, replacement: u8, ) -> (String, Option<usize>) { - let mut dst = slice.to_string().into_bytes(); + let mut dst = BString::from(slice); let result = replace_bytes(&mut dst, src, replacement); - (String::from_utf8(dst).unwrap(), result) + (dst.into_string().unwrap(), result) } #[test] @@ -607,7 +572,7 @@ and exhibited clearly, with a label attached.\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nlisa\n"); + assert_eq!(rdr.buffer(), "homer\nlisa\n"); assert_eq!(rdr.absolute_byte_offset(), 0); rdr.consume(5); assert_eq!(rdr.absolute_byte_offset(), 5); @@ -615,7 +580,7 @@ and exhibited clearly, with a label attached.\ assert_eq!(rdr.absolute_byte_offset(), 11); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "maggie"); + assert_eq!(rdr.buffer(), "maggie"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -630,7 +595,7 @@ and exhibited clearly, with a label attached.\ let mut rdr = LineBufferReader::new(bytes.as_bytes(), &mut linebuf); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nlisa\nmaggie\n"); + assert_eq!(rdr.buffer(), "homer\nlisa\nmaggie\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -645,7 +610,7 @@ and exhibited clearly, with a label attached.\ let mut rdr = LineBufferReader::new(bytes.as_bytes(), &mut linebuf); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "\n"); + assert_eq!(rdr.buffer(), "\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -660,7 +625,7 @@ and exhibited clearly, with a label attached.\ let mut rdr = LineBufferReader::new(bytes.as_bytes(), &mut linebuf); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "\n\n"); + assert_eq!(rdr.buffer(), "\n\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -698,12 +663,12 @@ and exhibited clearly, with a label attached.\ let mut linebuf = LineBufferBuilder::new().capacity(1).build(); let mut rdr = LineBufferReader::new(bytes.as_bytes(), &mut linebuf); - let mut got = vec![]; + let mut got = BString::new(); while rdr.fill().unwrap() { - got.extend(rdr.buffer()); + got.push(rdr.buffer()); rdr.consume_all(); } - assert_eq!(bytes, btos(&got)); + assert_eq!(bytes, got); assert_eq!(rdr.absolute_byte_offset(), bytes.len() as u64); assert_eq!(rdr.binary_byte_offset(), None); } @@ -718,11 +683,11 @@ and exhibited clearly, with a label attached.\ let mut rdr = LineBufferReader::new(bytes.as_bytes(), &mut linebuf); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\n"); + assert_eq!(rdr.buffer(), "homer\n"); rdr.consume_all(); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "lisa\n"); + assert_eq!(rdr.buffer(), "lisa\n"); rdr.consume_all(); // This returns an error because while we have just enough room to @@ -732,11 +697,11 @@ and exhibited clearly, with a label attached.\ assert!(rdr.fill().is_err()); // We can mush on though! - assert_eq!(btos(rdr.buffer()), "m"); + assert_eq!(rdr.buffer(), "m"); rdr.consume_all(); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "aggie"); + assert_eq!(rdr.buffer(), "aggie"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -752,16 +717,16 @@ and exhibited clearly, with a label attached.\ let mut rdr = LineBufferReader::new(bytes.as_bytes(), &mut linebuf); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\n"); + assert_eq!(rdr.buffer(), "homer\n"); rdr.consume_all(); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "lisa\n"); + assert_eq!(rdr.buffer(), "lisa\n"); rdr.consume_all(); // We have just enough space. assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "maggie"); + assert_eq!(rdr.buffer(), "maggie"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -777,7 +742,7 @@ and exhibited clearly, with a label attached.\ let mut rdr = LineBufferReader::new(bytes.as_bytes(), &mut linebuf); assert!(rdr.fill().is_err()); - assert_eq!(btos(rdr.buffer()), ""); + assert_eq!(rdr.buffer(), ""); } #[test] @@ -789,7 +754,7 @@ and exhibited clearly, with a label attached.\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nli\x00sa\nmaggie\n"); + assert_eq!(rdr.buffer(), "homer\nli\x00sa\nmaggie\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -808,7 +773,7 @@ and exhibited clearly, with a label attached.\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nli"); + assert_eq!(rdr.buffer(), "homer\nli"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -825,7 +790,7 @@ and exhibited clearly, with a label attached.\ let mut rdr = LineBufferReader::new(bytes.as_bytes(), &mut linebuf); assert!(!rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), ""); + assert_eq!(rdr.buffer(), ""); assert_eq!(rdr.absolute_byte_offset(), 0); assert_eq!(rdr.binary_byte_offset(), Some(0)); } @@ -841,7 +806,7 @@ and exhibited clearly, with a label attached.\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nlisa\nmaggie\n"); + assert_eq!(rdr.buffer(), "homer\nlisa\nmaggie\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -860,7 +825,7 @@ and exhibited clearly, with a label attached.\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nlisa\nmaggie"); + assert_eq!(rdr.buffer(), "homer\nlisa\nmaggie"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -878,7 +843,7 @@ and exhibited clearly, with a label attached.\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "\ + assert_eq!(rdr.buffer(), "\ For the Doctor Watsons of this world, as opposed to the Sherlock Holmeses, s\ "); @@ -901,7 +866,7 @@ Holmeses, s\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nli\nsa\nmaggie\n"); + assert_eq!(rdr.buffer(), "homer\nli\nsa\nmaggie\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -920,7 +885,7 @@ Holmeses, s\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "\nhomer\nlisa\nmaggie\n"); + assert_eq!(rdr.buffer(), "\nhomer\nlisa\nmaggie\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -939,7 +904,7 @@ Holmeses, s\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nlisa\nmaggie\n\n"); + assert_eq!(rdr.buffer(), "homer\nlisa\nmaggie\n\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); @@ -958,7 +923,7 @@ Holmeses, s\ assert!(rdr.buffer().is_empty()); assert!(rdr.fill().unwrap()); - assert_eq!(btos(rdr.buffer()), "homer\nlisa\nmaggie\n\n"); + assert_eq!(rdr.buffer(), "homer\nlisa\nmaggie\n\n"); rdr.consume_all(); assert!(!rdr.fill().unwrap()); |