Skip to content

Commit

Permalink
Merge pull request #6399 from tertsdiepraam/more-mem-usage
Browse files Browse the repository at this point in the history 
`more`: reduce memory usage a bit
  • Loading branch information
@sylvestre
sylvestre authored Dec 3, 2024
2 parents 843c0c2 + c1f82b1 commit 17d4e4f
Showing 1 changed file with 41 additions and 65 deletions.
106 changes: 41 additions & 65 deletions src/uu/more/src/more.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -98,10 +98,7 @@ pub fn uumain(args: impl uucore::Args) -> UResult<()> {
println!("{panic_info}");
}));

let matches = match uu_app().try_get_matches_from(args) {
Ok(m) => m,
Err(e) => return Err(e.into()),
};
let matches = uu_app().try_get_matches_from(args)?;

let mut options = Options::from(&matches);

Expand Down Expand Up @@ -308,12 +305,12 @@ fn more(
rows = number;
}

let lines = break_buff(buff, usize::from(cols));
let lines = break_buff(buff, cols as usize);

let mut pager = Pager::new(rows, lines, next_file, options);

if options.pattern.is_some() {
match search_pattern_in_file(&pager.lines, &options.pattern) {
if let Some(pat) = options.pattern.as_ref() {
match search_pattern_in_file(&pager.lines, pat) {
Some(number) => pager.upper_mark = number,
None => {
execute!(stdout, terminal::Clear(terminal::ClearType::CurrentLine))?;
Expand Down Expand Up @@ -446,8 +443,8 @@ struct Pager<'a> {
// The current line at the top of the screen
upper_mark: usize,
// The number of rows that fit on the screen
content_rows: u16,
lines: Vec<String>,
content_rows: usize,
lines: Vec<&'a str>,
next_file: Option<&'a str>,
line_count: usize,
silent: bool,
Expand All @@ -456,11 +453,11 @@ struct Pager<'a> {
}

impl<'a> Pager<'a> {
fn new(rows: u16, lines: Vec<String>, next_file: Option<&'a str>, options: &Options) -> Self {
fn new(rows: u16, lines: Vec<&'a str>, next_file: Option<&'a str>, options: &Options) -> Self {
let line_count = lines.len();
Self {
upper_mark: options.from_line,
content_rows: rows.saturating_sub(1),
content_rows: rows.saturating_sub(1) as usize,
lines,
next_file,
line_count,
Expand All @@ -472,30 +469,25 @@ impl<'a> Pager<'a> {

fn should_close(&mut self) -> bool {
self.upper_mark
.saturating_add(self.content_rows.into())
.saturating_add(self.content_rows)
.ge(&self.line_count)
}

fn page_down(&mut self) {
// If the next page down position __after redraw__ is greater than the total line count,
// the upper mark must not grow past top of the screen at the end of the open file.
if self
.upper_mark
.saturating_add(self.content_rows as usize * 2)
.ge(&self.line_count)
{
self.upper_mark = self.line_count - self.content_rows as usize;
if self.upper_mark.saturating_add(self.content_rows * 2) >= self.line_count {
self.upper_mark = self.line_count - self.content_rows;
return;
}

self.upper_mark = self.upper_mark.saturating_add(self.content_rows.into());
self.upper_mark = self.upper_mark.saturating_add(self.content_rows);
}

fn page_up(&mut self) {
let content_row_usize: usize = self.content_rows.into();
self.upper_mark = self
.upper_mark
.saturating_sub(content_row_usize.saturating_add(self.line_squeezed));
.saturating_sub(self.content_rows.saturating_add(self.line_squeezed));

if self.squeeze {
let iter = self.lines.iter().take(self.upper_mark).rev();
Expand All @@ -520,15 +512,15 @@ impl<'a> Pager<'a> {
// TODO: Deal with column size changes.
fn page_resize(&mut self, _: u16, row: u16, option_line: Option<u16>) {
if option_line.is_none() {
self.content_rows = row.saturating_sub(1);
self.content_rows = row.saturating_sub(1) as usize;
};
}

fn draw(&mut self, stdout: &mut std::io::Stdout, wrong_key: Option<char>) {
self.draw_lines(stdout);
let lower_mark = self
.line_count
.min(self.upper_mark.saturating_add(self.content_rows.into()));
.min(self.upper_mark.saturating_add(self.content_rows));
self.draw_prompt(stdout, lower_mark, wrong_key);
stdout.flush().unwrap();
}
Expand All @@ -541,7 +533,7 @@ impl<'a> Pager<'a> {
let mut displayed_lines = Vec::new();
let mut iter = self.lines.iter().skip(self.upper_mark);

while displayed_lines.len() < self.content_rows as usize {
while displayed_lines.len() < self.content_rows {
match iter.next() {
Some(line) => {
if self.squeeze {
Expand Down Expand Up @@ -608,13 +600,12 @@ impl<'a> Pager<'a> {
}
}

fn search_pattern_in_file(lines: &[String], pattern: &Option<String>) -> Option<usize> {
let pattern = pattern.clone().unwrap_or_default();
fn search_pattern_in_file(lines: &[&str], pattern: &str) -> Option<usize> {
if lines.is_empty() || pattern.is_empty() {
return None;
}
for (line_number, line) in lines.iter().enumerate() {
if line.contains(pattern.as_str()) {
if line.contains(pattern) {
return Some(line_number);
}
}
Expand All @@ -630,20 +621,22 @@ fn paging_add_back_message(options: &Options, stdout: &mut std::io::Stdout) -> U
}

// Break the lines on the cols of the terminal
fn break_buff(buff: &str, cols: usize) -> Vec<String> {
let mut lines = Vec::with_capacity(buff.lines().count());
fn break_buff(buff: &str, cols: usize) -> Vec<&str> {
// We _could_ do a precise with_capacity here, but that would require scanning the
// whole buffer. Just guess a value instead.
let mut lines = Vec::with_capacity(2048);

for l in buff.lines() {
lines.append(&mut break_line(l, cols));
}
lines
}

fn break_line(line: &str, cols: usize) -> Vec<String> {
fn break_line(line: &str, cols: usize) -> Vec<&str> {
let width = UnicodeWidthStr::width(line);
let mut lines = Vec::new();
if width < cols {
lines.push(line.to_string());
lines.push(line);
return lines;
}

Expand All @@ -655,14 +648,14 @@ fn break_line(line: &str, cols: usize) -> Vec<String> {
total_width += width;

if total_width > cols {
lines.push(line[last_index..index].to_string());
lines.push(&line[last_index..index]);
last_index = index;
total_width = width;
}
}

if last_index != line.len() {
lines.push(line[last_index..].to_string());
lines.push(&line[last_index..]);
}
lines
}
Expand Down Expand Up @@ -721,49 +714,32 @@ mod tests {
#[test]
fn test_search_pattern_empty_lines() {
let lines = vec![];
let pattern = Some(String::from("pattern"));
assert_eq!(None, search_pattern_in_file(&lines, &pattern));
let pattern = "pattern";
assert_eq!(None, search_pattern_in_file(&lines, pattern));
}

#[test]
fn test_search_pattern_empty_pattern() {
let lines = vec![String::from("line1"), String::from("line2")];
let pattern = None;
assert_eq!(None, search_pattern_in_file(&lines, &pattern));
let lines = vec!["line1", "line2"];
let pattern = "";
assert_eq!(None, search_pattern_in_file(&lines, pattern));
}

#[test]
fn test_search_pattern_found_pattern() {
let lines = vec![
String::from("line1"),
String::from("line2"),
String::from("pattern"),
];
let lines2 = vec![
String::from("line1"),
String::from("line2"),
String::from("pattern"),
String::from("pattern2"),
];
let lines3 = vec![
String::from("line1"),
String::from("line2"),
String::from("other_pattern"),
];
let pattern = Some(String::from("pattern"));
assert_eq!(2, search_pattern_in_file(&lines, &pattern).unwrap());
assert_eq!(2, search_pattern_in_file(&lines2, &pattern).unwrap());
assert_eq!(2, search_pattern_in_file(&lines3, &pattern).unwrap());
let lines = vec!["line1", "line2", "pattern"];
let lines2 = vec!["line1", "line2", "pattern", "pattern2"];
let lines3 = vec!["line1", "line2", "other_pattern"];
let pattern = "pattern";
assert_eq!(2, search_pattern_in_file(&lines, pattern).unwrap());
assert_eq!(2, search_pattern_in_file(&lines2, pattern).unwrap());
assert_eq!(2, search_pattern_in_file(&lines3, pattern).unwrap());
}

#[test]
fn test_search_pattern_not_found_pattern() {
let lines = vec![
String::from("line1"),
String::from("line2"),
String::from("something"),
];
let pattern = Some(String::from("pattern"));
assert_eq!(None, search_pattern_in_file(&lines, &pattern));
let lines = vec!["line1", "line2", "something"];
let pattern = "pattern";
assert_eq!(None, search_pattern_in_file(&lines, pattern));
}
}

0 comments on commit 17d4e4f

Please sign in to comment.