Use the original os-release file parser

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Rubens Brandao 2023-12-28 13:03:02 -03:00
parent 7229dd85f9
commit 05cb051f05
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1 changed files with 157 additions and 26 deletions

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@ -1,7 +1,7 @@
use std::fmt;
use std::{collections::BTreeMap, str::FromStr};
use anyhow::{Context, Result};
use anyhow::Result;
use crate::generation::Generation;
@ -58,31 +58,162 @@ impl FromStr for OsRelease {
fn from_str(value: &str) -> Result<Self> {
let mut map = BTreeMap::new();
// All valid lines
let lines = value
.lines()
.map(str::trim)
.filter(|x| !x.starts_with('#') && !x.is_empty());
// Split into keys/values
let key_value_lines = lines.map(|x| x.split('=').collect::<Vec<&str>>());
for kv in key_value_lines {
let k = kv
.first()
.with_context(|| format!("Failed to get first element from {kv:?}"))?;
let v = kv
.get(1)
.map(|s| s.strip_prefix(|c| c == '"' || c == '\'').unwrap_or(s))
.map(|s| s.strip_suffix(|c| c == '"' || c == '\'').unwrap_or(s))
.with_context(|| format!("Failed to get second element from {kv:?}"))?;
// Clean up the value. We already have the value without leading/tailing "
// so we just need to unescape the string.
let v = v
.replace("\\$", "$")
.replace("\\\"", "\"")
.replace("\\`", "`")
.replace("\\\\", "\\");
enum State {
PreKey,
Key,
PreValue,
Value,
ValueEscape,
SingleQuoteValue,
DoubleQuoteValue,
DoubleQuoteValueEscape,
Comment,
CommentEscape,
}
use State::*;
map.insert(String::from(*k), v);
let mut state = State::PreKey;
let mut current_key = String::new();
let mut current_value = String::new();
const COMMENTS: &str = "#;";
const WHITESPACE: &str = " \t\n\r";
const NEWLINE: &str = "\r\n";
const SHELL_NEED_ESCAPE: &str = "\"\\`$";
for c in value.chars() {
match state {
PreKey => {
if COMMENTS.contains(c) {
state = Comment;
} else if !WHITESPACE.contains(c) {
state = Key;
current_key.push(c);
}
}
Key => {
if NEWLINE.contains(c) {
// keys without any '=' are simply ignored
state = PreKey;
current_key.clear();
} else if c == '=' {
state = PreValue;
} else {
current_key.push(c);
}
}
PreValue => {
if NEWLINE.contains(c) {
state = PreKey;
// strip trailing whitespace from key
let key = current_key.trim_end().to_owned();
map.insert(key, current_value.clone());
current_key.clear();
current_value.clear();
} else if c == '\'' {
state = SingleQuoteValue;
} else if c == '"' {
state = DoubleQuoteValue;
} else if c == '\\' {
state = ValueEscape;
} else if !WHITESPACE.contains(c) {
state = Value;
current_value.push(c);
}
}
Value => {
if NEWLINE.contains(c) {
state = PreKey;
// strip trailing whitespace from key
let key = current_key.trim_end().to_owned();
// strip trailing whitespace from value
let value = current_value.trim_end().to_owned();
map.insert(key, value);
current_key.clear();
current_value.clear();
} else if c == '\\' {
state = ValueEscape;
} else {
current_value.push(c);
}
}
ValueEscape => {
state = Value;
if !NEWLINE.contains(c) {
// Escaped newlines we eat up entirely
current_value.push(c);
}
}
SingleQuoteValue => {
if c == '\'' {
state = PreValue;
} else {
current_value.push(c);
}
}
DoubleQuoteValue => {
if c == '"' {
state = PreValue;
} else if c == '\\' {
state = DoubleQuoteValueEscape;
} else {
current_value.push(c);
}
}
DoubleQuoteValueEscape => {
state = DoubleQuoteValue;
if SHELL_NEED_ESCAPE.contains(c) {
// If this is a char that needs escaping, just unescape it.
current_value.push(c);
} else if c != '\n' {
// If other char than what needs escaping, keep the "\"
// in place, like the real shell does.
current_value.push('\\');
current_value.push(c);
}
// Escaped newlines (aka "continuation lines") are eaten up entirely
}
Comment => {
if c == '\\' {
state = CommentEscape;
} else if NEWLINE.contains(c) {
state = PreKey;
}
}
CommentEscape => {
log::debug!("The line which doesn't begin with \";\" or \"#\", but follows a comment line trailing with escape is now treated as a non comment line since v254.");
if NEWLINE.contains(c) {
state = PreKey;
} else {
state = Comment;
}
}
}
}
if matches!(
state,
PreValue
| Value
| ValueEscape
| SingleQuoteValue
| DoubleQuoteValue
| DoubleQuoteValueEscape
) {
// strip trailing whitespace from key
let key = current_key.trim_end().to_owned();
let value = if matches!(state, Value) {
// strip trailing whitespace from value
current_value.trim_end().to_owned()
} else {
current_value
};
map.insert(key, value);
}
Ok(Self(map))
@ -138,7 +269,7 @@ mod tests {
assert!(os_release.0["ESCAPED_DOLLAR"] == "$1.2");
assert!(os_release.0["UNESCAPED_BACKTICK"] == "`1.2");
assert!(os_release.0["ESCAPED_BACKTICK"] == "`1.2");
assert!(os_release.0["UNESCAPED_QUOTE"] == "\"1.2");
assert!(os_release.0["UNESCAPED_QUOTE"] == "1.2\"");
assert!(os_release.0["ESCAPED_QUOTE"] == "\"1.2");
Ok(())