kill lagging preview processes

Cargo.toml

@@ -15,4 +15,5 @@ mime-detective = "*"
 rayon = "1.0.3"
 dirs-2 = "1.1.0"
 users = "0.8"
-chrono = "0.4"
+chrono = "0.4"
+libc = "*"

src/main.rs

@@ -9,6 +9,7 @@ extern crate users;
 extern crate chrono;
 extern crate mime_detective;
 extern crate rayon;
+extern crate libc;
 
 use termion::input::MouseTerminal;
 use termion::raw::IntoRawMode;

src/preview.rs

@@ -1,5 +1,6 @@
 use std::io::Write;
 use std::sync::Mutex;
+use std::sync::Arc;
 
 use crate::coordinates::{Coordinates, Position, Size};
 use crate::files::{File, Files, Kind};
@@ -8,22 +9,31 @@ use crate::textview::TextView;
 use crate::widget::Widget;
 
 
-pub struct InstanceCounter(Mutex<usize>);
-impl PartialEq for InstanceCounter {
-    fn eq(&self, other: &Self) -> bool {
-        let instance = self.0.lock().unwrap();
-        let other = other.0.lock().unwrap();
-        *instance == *other
-    }
+lazy_static! {
+    static ref PIDS: Arc<Mutex<Vec<i32>>> = { Arc::new(Mutex::new(vec![])) };
+    static ref CURFILE: Arc<Mutex<Option<File>>> = { Arc::new(Mutex::new(None)) };
 }
 
+fn kill_procs() {
+    let mut pids = PIDS.lock().unwrap();
+    for pid in &*pids {
+        let msg = format!("KILLING PROC: {}", pid);
+        unsafe { libc::kill(*pid, 9); }
+    }
+    pids.clear();
+}
+
+fn is_current(file: &File) -> bool {
+    CURFILE.lock().unwrap().as_ref().unwrap() == file
+}
+
+
 
 #[derive(PartialEq)]
 pub struct Previewer {
     pub file: Option<File>,
     pub buffer: String,
     pub coordinates: Coordinates,
-    pub instances: InstanceCounter
 }
 
 impl Previewer {
@@ -32,30 +42,29 @@ impl Previewer {
             file: None,
             buffer: String::new(),
             coordinates: Coordinates::new(),
-            instances: InstanceCounter(Mutex::new(0))
         }
     }
     pub fn set_file(&mut self, file: &File) {
-        //return;
-        let mut instance = self.instances.0.try_lock().unwrap();
-        if *instance > 2 { return }
-        *instance = *instance + 1;
         let coordinates = self.coordinates.clone();
         let file = file.clone();
         let redraw = crate::term::reset() + &self.get_redraw_empty_list(0);
 
+        *CURFILE.lock().unwrap() = Some(file.clone());
 
-        //self.threads.install(|| {
         std::thread::spawn(move || {
+            kill_procs();
             match &file.kind {
                 Kind::Directory => match Files::new_from_path(&file.path) {
                     Ok(files) => {
+                        if !is_current(&file) { return }
                         let len = files.len();
                         if len == 0 { return };
                         let mut file_list = ListView::new(files);
                         file_list.set_coordinates(&coordinates);
                         file_list.refresh();
+                        if !is_current(&file) { return }
                         file_list.animate_slide_up();
+
                     }
                     Err(err) => {
                         crate::window::show_status(&format!("Can't preview because: {}", err));
@@ -65,21 +74,34 @@ impl Previewer {
                 _ => {
                     if file.get_mime() == Some("text".to_string()) {
                         let mut textview = TextView::new_from_file(&file);
+                        if !is_current(&file) { return }
                         textview.set_coordinates(&coordinates);
                         textview.refresh();
+                        if !is_current(&file) { return }
                         textview.animate_slide_up();
                     } else {
-                        let output =
-                            std::process::Command::new("scope.sh").arg(&file.name)
+                        let process =
+                            std::process::Command::new("scope.sh")
+                            .arg(&file.name)
                             .arg("10".to_string())
                             .arg("10".to_string())
                             .arg("".to_string())
                             .arg("false".to_string())
-                            .output().unwrap();
+                            .stdin(std::process::Stdio::null())
+                            .stdout(std::process::Stdio::piped())
+                            .stderr(std::process::Stdio::null())
+                            .spawn().unwrap();
 
+                        let pid = process.id();
+                        PIDS.lock().unwrap().push(pid as i32);
 
+                        if !is_current(&file) { return }
 
-                        if output.status.code().unwrap() == 0 {
+                        let output = process.wait_with_output().unwrap();
+
+                        let status = output.status.code().unwrap();
+
+                        if status == 0 || status == 5 && is_current(&file) {
                             let output = std::str::from_utf8(&output.stdout)
                                 .unwrap()
                                 .to_string();
@@ -95,12 +117,11 @@ impl Previewer {
                         {
                             write!(std::io::stdout(), "{}", redraw).unwrap();
                         }
+                        PIDS.lock().unwrap().pop();
                     }
-
                 }
             }
         });
-        *instance = *instance - 1;
     }
 }