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Author: ryuichiueda

Cargo.toml

@@ -10,3 +10,4 @@ nix = { version = "0.28.0", features = ["fs", "process", "signal", "term", "user
 termion = "4.0.3"
 unicode-width = "0.1.11"
 signal-hook = "0.3.17"
+rev_lines = "0.3.0"

src/core.rs

@@ -3,6 +3,7 @@
 
 pub mod builtins;
 pub mod data;
+pub mod history;
 pub mod jobtable;
 
 use self::data::Data;
@@ -21,6 +22,7 @@ use std::sync::atomic::Ordering::Relaxed;
 
 pub struct ShellCore {
     pub data: Data,
+    rewritten_history: HashMap<usize, String>,
     pub history: Vec<String>,
     pub builtins: HashMap<String, fn(&mut ShellCore, &mut Vec<String>) -> i32>,
     pub sigint: Arc<AtomicBool>,
@@ -51,7 +53,8 @@ impl ShellCore {
     pub fn new() -> ShellCore {
         let mut core = ShellCore{
             data: Data::new(),
-            history: Vec::new(),
+            rewritten_history: HashMap::new(),
+            history: vec![],
             builtins: HashMap::new(),
             sigint: Arc::new(AtomicBool::new(false)),
             is_subshell: false,

src/core/history.rs

@@ -0,0 +1,77 @@
+//SPDXFileCopyrightText: 2024 Ryuichi Ueda ryuichiueda@gmail.com
+//SPDXLicense-Identifier: BSD-3-Clause
+
+use crate::ShellCore;
+use rev_lines::RevLines;
+use std::fs::File;
+use std::io::{BufReader, BufWriter, Write};
+use std::fs::OpenOptions;
+
+impl ShellCore {
+    pub fn fetch_history(&mut self, pos: usize, prev: usize, prev_str: String) -> String {
+        if prev < self.history.len() {
+            self.history[prev] = prev_str;
+        }else{
+            self.rewritten_history.insert(prev + 1 - self.history.len(), prev_str);
+        }
+
+        if pos < self.history.len() {
+            self.history[pos].clone()
+        }else{
+            self.fetch_history_file(pos + 1 - self.history.len())
+        }
+    }
+
+    pub fn fetch_history_file(&mut self, pos: usize) -> String {
+        if let Some(s) = self.rewritten_history.get(&pos) {
+            return s.to_string();
+        }
+        if pos == 0 {
+            return String::new();
+        }
+
+        let mut file_line = pos - 1;
+        if let Ok(n) = self.data.get_param("HISTFILESIZE").parse::<usize>() {
+            file_line %= n;
+        }
+
+        if let Ok(hist_file) = File::open(self.data.get_param("HISTFILE")){
+            let mut rev_lines = RevLines::new(BufReader::new(hist_file));
+            if let Some(Ok(s)) = rev_lines.nth(file_line) {
+                return s;
+            }
+        }
+
+        String::new()
+    }
+
+    pub fn write_history_to_file(&mut self) {
+        if ! self.data.flags.contains('i') || self.is_subshell {
+            return;
+        }
+        let filename = self.data.get_param("HISTFILE");
+        if filename == "" {
+            eprintln!("sush: HISTFILE is not set");
+            return;
+        }
+    
+        let file = match OpenOptions::new().create(true)
+                .write(true).append(true).open(&filename) {
+            Ok(f) => f,
+            _     => {
+                eprintln!("sush: invalid history file");
+                return;
+            },
+        };
+    
+        let mut f = BufWriter::new(file);
+        for h in self.history.iter().rev() {
+            if h == "" {
+                continue;
+            }
+            let _ = f.write(h.as_bytes());
+            let _ = f.write(&vec![0x0A]);
+        }
+        let _ = f.flush();
+    }
+}

src/main.rs

@@ -62,6 +62,18 @@ fn main() {
     main_loop(&mut core);
 }
 
+fn set_history(core: &mut ShellCore, s: &str) {
+    if core.history.len() == 0 {
+        return;
+    }
+
+    core.history[0] = s.trim_end().replace("\n", "↵ \0").to_string();
+    if core.history[0].len() == 0
+    || (core.history.len() > 1 && core.history[0] == core.history[1]) {
+        core.history.remove(0);
+    }
+}
+
 fn input_interrupt_check(feeder: &mut Feeder, core: &mut ShellCore) -> bool {
     if ! core.sigint.load(Relaxed) { //core.input_interrupt {
         return false;
@@ -89,7 +101,10 @@ fn main_loop(core: &mut ShellCore) {
         }
 
         match Script::parse(&mut feeder, core){
-            Some(mut s) => s.exec(core),
+            Some(mut s) => {
+                s.exec(core);
+                set_history(core, &s.get_text());
+            },
             None => {},
         }
         core.sigint.store(false, Relaxed);