feat: custom ssh config parser (#63)

Cargo.toml

@@ -16,6 +16,7 @@ ratatui = "0.26.1"
 regex = { version = "1.10.3", default-features = false, features = ["std"] }
 shellexpand = "3.1.0"
 shlex = "1.3.0"
-ssh2-config = "0.2.3"
+strum = "0.26.1"
+strum_macros = "0.26.1"
 tui-input = "0.8.0"
 unicode-width = "0.1.11"

src/main.rs

@@ -1,4 +1,5 @@
 pub mod ssh;
+pub mod ssh_config;
 pub mod ui;
 
 use clap::Parser;

src/ssh.rs

@@ -1,30 +1,37 @@
 use itertools::Itertools;
 use regex::Regex;
-use ssh2_config::{ParseRule, SshConfig};
 use std::collections::VecDeque;
 use std::error::Error;
-use std::fs::File;
-use std::{io::BufReader, process::Command};
+use std::process::Command;
+
+use crate::ssh_config::{self, HostVecExt};
 
 #[derive(Debug, Clone)]
 pub struct Host {
     pub hostname: String,
     pub aliases: String,
-    pub user: String,
+    pub user: Option<String>,
     pub target: String,
-    pub port: String,
+    pub port: Option<String>,
 }
 
 /// # Errors
 ///
 /// Will return `Err` if the SSH command cannot be executed.
 pub fn connect(host: &Host) -> Result<(), Box<dyn Error>> {
-    Command::new("ssh")
-        .arg(format!("{}@{}", host.user, host.target))
-        .arg("-p")
-        .arg(&host.port)
-        .spawn()?
-        .wait()?;
+    let mut command = Command::new("ssh");
+
+    if let Some(user) = &host.user {
+        command.arg(format!("{}@{}", user, host.target));
+    } else {
+        command.arg(host.target.clone());
+    }
+
+    if let Some(port) = &host.port {
+        command.arg("-p").arg(port);
+    }
+
+    command.spawn()?.wait()?;
 
     Ok(())
 }
@@ -39,9 +46,9 @@ pub fn connect(host: &Host) -> Result<(), Box<dyn Error>> {
 /// # Errors
 ///
 /// Will return `Err` if the command cannot be executed.
-/// 
+///
 /// # Panics
-/// 
+///
 /// Will panic if the regex cannot be compiled.
 pub fn run_with_pattern(pattern: &str, host: &Host) -> Result<(), Box<dyn Error>> {
     let re = Regex::new(r"(?P<skip>%%)|(?P<h>%h)|(?P<u>%u)|(?P<p>%p)").unwrap();
@@ -51,9 +58,9 @@ pub fn run_with_pattern(pattern: &str, host: &Host) -> Result<(), Box<dyn Error>
         } else if caps.name("h").is_some() {
             host.hostname.clone()
         } else if caps.name("u").is_some() {
-            host.user.clone()
+            host.user.clone().unwrap_or_default()
         } else if caps.name("p").is_some() {
-            host.port.clone()
+            host.port.clone().unwrap_or_default()
         } else {
             String::new()
         }
@@ -80,22 +87,24 @@ pub fn parse_config(raw_path: &String) -> Result<Vec<Host>, Box<dyn Error>> {
         .ok_or("Failed to convert path to string")?
         .to_string();
 
-    let mut reader = BufReader::new(File::open(path)?);
-    let config = SshConfig::default().parse(&mut reader, ParseRule::STRICT)?;
-
-    let hosts = config
-        .get_hosts()
+    let hosts = ssh_config::Parser::new()
+        .parse_file(path)?
+        .apply_patterns()
+        .merge_same_hosts()
         .iter()
-        .filter(|host| host.params.host_name.is_some())
+        .filter(|host| host.get(&ssh_config::EntryType::Hostname).is_some())
         .map(|host| Host {
-            hostname: host.pattern[0].pattern.clone(),
-            aliases: host.pattern[1..]
-                .iter()
-                .map(|p| p.pattern.clone())
-                .join(", "),
-            user: host.params.user.clone().unwrap_or_default(),
-            target: host.params.host_name.clone().unwrap_or_default(),
-            port: host.params.port.unwrap_or(22).to_string(),
+            hostname: host
+                .get_patterns()
+                .first()
+                .unwrap_or(&String::new())
+                .clone(),
+            aliases: host.get_patterns().iter().skip(1).join(", "),
+            user: host.get(&ssh_config::EntryType::User),
+            target: host
+                .get(&ssh_config::EntryType::Hostname)
+                .unwrap_or_default(),
+            port: host.get(&ssh_config::EntryType::Port),
         })
         .collect();
 

src/ssh_config/host.rs

@@ -0,0 +1,223 @@
+use regex::Regex;
+use std::collections::HashMap;
+
+use super::EntryType;
+
+pub(crate) type Entry = (EntryType, String);
+
+#[derive(Debug, Clone)]
+pub struct Host {
+    patterns: Vec<String>,
+    entries: HashMap<EntryType, String>,
+}
+
+impl Host {
+    #[must_use]
+    pub fn new(patterns: Vec<String>) -> Host {
+        Host {
+            patterns,
+            entries: HashMap::new(),
+        }
+    }
+
+    pub fn update(&mut self, entry: Entry) {
+        self.entries.insert(entry.0, entry.1);
+    }
+
+    pub(crate) fn extend_patterns(&mut self, host: &Host) {
+        self.patterns.extend(host.patterns.clone());
+    }
+
+    pub(crate) fn extend_entries(&mut self, host: &Host) {
+        self.entries.extend(host.entries.clone());
+    }
+
+    pub(crate) fn extend_if_not_contained(&mut self, host: &Host) {
+        for (key, value) in &host.entries {
+            if !self.entries.contains_key(key) {
+                self.entries.insert(key.clone(), value.clone());
+            }
+        }
+    }
+
+    #[allow(clippy::must_use_candidate)]
+    pub fn get_patterns(&self) -> &Vec<String> {
+        &self.patterns
+    }
+
+    /// # Panics
+    ///
+    /// Will panic if the regex cannot be compiled.
+    #[allow(clippy::must_use_candidate)]
+    pub fn matching_pattern_regexes(&self) -> Vec<(Regex, bool)> {
+        if self.patterns.is_empty() {
+            return Vec::new();
+        }
+
+        self.patterns
+            .iter()
+            .filter_map(|pattern| {
+                let contains_wildcard =
+                    pattern.contains('*') || pattern.contains('?') || pattern.contains('!');
+                if !contains_wildcard {
+                    return None;
+                }
+
+                let mut pattern = pattern
+                    .replace('.', r"\.")
+                    .replace('*', ".*")
+                    .replace('?', ".");
+
+                let is_negated = pattern.starts_with('!');
+                if is_negated {
+                    pattern.remove(0);
+                }
+
+                pattern = format!("^{pattern}$");
+                Some((Regex::new(&pattern).unwrap(), is_negated))
+            })
+            .collect()
+    }
+
+    #[allow(clippy::must_use_candidate)]
+    pub fn get(&self, entry: &EntryType) -> Option<String> {
+        self.entries.get(entry).cloned()
+    }
+
+    #[allow(clippy::must_use_candidate)]
+    pub fn is_empty(&self) -> bool {
+        self.entries.is_empty()
+    }
+}
+
+#[allow(clippy::module_name_repetitions)]
+pub trait HostVecExt {
+    /// Merges the hosts with the same entries into one host.
+    fn merge_same_hosts(&mut self) -> &mut Self;
+
+    /// Spreads the hosts with multiple patterns into multiple hosts with one pattern.
+    fn spread(&mut self) -> &mut Self;
+
+    /// Apply patterns entries to non-pattern hosts and remove the pattern hosts.
+    fn apply_patterns(&mut self) -> &mut Self;
+}
+
+impl HostVecExt for Vec<Host> {
+    fn merge_same_hosts(&mut self) -> &mut Self {
+        for i in (0..self.len()).rev() {
+            for j in (0..i).rev() {
+                if self[i].entries != self[j].entries {
+                    continue;
+                }
+
+                let host = self[i].clone();
+                self[j].extend_patterns(&host);
+                self[j].extend_entries(&host);
+                self.remove(i);
+                break;
+            }
+        }
+
+        self
+    }
+
+    fn spread(&mut self) -> &mut Self {
+        let mut hosts = Vec::new();
+
+        for host in self.iter_mut() {
+            let patterns = host.get_patterns();
+            if patterns.is_empty() {
+                hosts.push(host.clone());
+                continue;
+            }
+
+            for pattern in patterns {
+                let mut new_host = host.clone();
+                new_host.patterns = vec![pattern.clone()];
+                hosts.push(new_host);
+            }
+        }
+
+        self
+    }
+
+    /// Apply patterns entries to non-pattern hosts and remove the pattern hosts.
+    ///
+    /// You might want to call [`HostVecExt::merge_same_hosts`] after this.
+    fn apply_patterns(&mut self) -> &mut Self {
+        let hosts = self.spread();
+        let mut pattern_indexes = Vec::new();
+
+        for i in 0..hosts.len() {
+            let matching_pattern_regexes = hosts[i].matching_pattern_regexes();
+            if matching_pattern_regexes.is_empty() {
+                continue;
+            }
+
+            pattern_indexes.push(i);
+
+            for j in (i + 1)..hosts.len() {
+                if !hosts[j].matching_pattern_regexes().is_empty() {
+                    continue;
+                }
+
+                for (regex, is_negated) in &matching_pattern_regexes {
+                    if regex.is_match(&hosts[j].patterns[0]) == *is_negated {
+                        continue;
+                    }
+
+                    let host = hosts[i].clone();
+                    hosts[j].extend_if_not_contained(&host);
+                    break;
+                }
+            }
+        }
+
+        for i in pattern_indexes.into_iter().rev() {
+            hosts.remove(i);
+        }
+
+        hosts
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_apply_patterns() {
+        let mut hosts = Vec::new();
+
+        let mut host = Host::new(vec!["*".to_string()]);
+        host.update((EntryType::Hostname, "example.com".to_string()));
+        hosts.push(host);
+
+        let mut host = Host::new(vec!["!example.com".to_string()]);
+        host.update((EntryType::User, "hello".to_string()));
+        hosts.push(host);
+
+        let mut host = Host::new(vec!["example.com".to_string()]);
+        host.update((EntryType::Port, "22".to_string()));
+        hosts.push(host);
+
+        let mut host = Host::new(vec!["hello.com".to_string()]);
+        host.update((EntryType::Port, "22".to_string()));
+        hosts.push(host);
+
+        let hosts = hosts.apply_patterns();
+
+        assert_eq!(hosts.len(), 2);
+
+        assert_eq!(hosts[0].patterns[0], "example.com");
+        assert_eq!(hosts[0].entries.len(), 2);
+        assert_eq!(hosts[0].entries[&EntryType::Hostname], "example.com");
+        assert_eq!(hosts[0].entries[&EntryType::Port], "22");
+
+        assert_eq!(hosts[1].patterns[0], "hello.com");
+        assert_eq!(hosts[1].entries.len(), 3);
+        assert_eq!(hosts[1].entries[&EntryType::Hostname], "example.com");
+        assert_eq!(hosts[1].entries[&EntryType::User], "hello");
+        assert_eq!(hosts[1].entries[&EntryType::Port], "22");
+    }
+}