fix(compatibility): some fixes for htop (#53)

* Moved all log to file functions to one module.

* Moved logging to file function to utils module.

* Housekeeping.

* Housekeeping.

* Started investigation into htop CSIs.

* Used better function for scrolling.

* Minor cleanup.

* Cleanup and start of scroll region rotation.

* Implemented scroll region rotation.

* Improved performace.

* New SCI found.

* Typo.

* Typo.

* Removed logging function.

* Added scroll rotation functions.

* Typo.

* Moved all logging function to one module.

* Attempt at making htop work.

* Reverted unneeded changes.

* Improved log file name creation.

* Ran rust fmt.

* PR review edits.

* PR review edits.

* Used mark_for_rerender function.

* Removed _ prefix from logging functions.

11 files changed, 188 insertions, 161 deletions

diff --git a/src/boundaries.rs b/src/boundaries.rs
index 436d767b..9f414f1c 100644
--- a/src/boundaries.rs
+++ b/src/boundaries.rs
@@ -1,17 +1,5 @@
 use std::collections::HashMap;
 
-fn _debug_log_to_file(message: String) {
-    use std::fs::OpenOptions;
-    use std::io::prelude::*;
-    let mut file = OpenOptions::new()
-        .append(true)
-        .create(true)
-        .open("/tmp/mosaic-log.txt")
-        .unwrap();
-    file.write_all(message.as_bytes()).unwrap();
-    file.write_all("\n".as_bytes()).unwrap();
-}
-
 pub mod boundary_type {
     pub const TOP_RIGHT: &str = "┐";
     pub const VERTICAL: &str = "│";
diff --git a/src/layout.rs b/src/layout.rs
index e80c76b2..f4297bfd 100644
--- a/src/layout.rs
+++ b/src/layout.rs
@@ -1,18 +1,6 @@
 use crate::terminal_pane::PositionAndSize;
 use serde::{Deserialize, Serialize};
 
-fn _debug_log_to_file(message: String) {
-    use std::fs::OpenOptions;
-    use std::io::prelude::*;
-    let mut file = OpenOptions::new()
-        .append(true)
-        .create(true)
-        .open("/tmp/mosaic-log.txt")
-        .unwrap();
-    file.write_all(message.as_bytes()).unwrap();
-    file.write_all("\n".as_bytes()).unwrap();
-}
-
 fn split_space_to_parts_vertically(
     space_to_split: &PositionAndSize,
     percentages: Vec<u8>,
diff --git a/src/main.rs b/src/main.rs
index 315e8eb1..d331451c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,12 +1,12 @@
-#[cfg(test)]
-mod tests;
-
 mod boundaries;
 mod layout;
 mod os_input_output;
 mod pty_bus;
 mod screen;
 mod terminal_pane;
+#[cfg(test)]
+mod tests;
+mod utils;
 
 use std::io::{Read, Write};
 use std::os::unix::net::UnixStream;
@@ -22,6 +22,7 @@ use crate::layout::Layout;
 use crate::os_input_output::{get_os_input, OsApi};
 use crate::pty_bus::{PtyBus, PtyInstruction, VteEvent};
 use crate::screen::{Screen, ScreenInstruction};
+use crate::utils::{consts::MOSAIC_TMP_FOLDER, logging::*};
 
 #[derive(Serialize, Deserialize, Debug)]
 enum ApiCommand {
@@ -53,46 +54,28 @@ pub struct Opt {
     debug: bool,
 }
 
-fn _debug_log_to_file(message: String) {
-    use std::fs::OpenOptions;
-    use std::io::prelude::*;
-    let mut file = OpenOptions::new()
-        .append(true)
-        .create(true)
-        .open("/tmp/mosaic-log.txt")
-        .unwrap();
-    file.write_all(message.as_bytes()).unwrap();
-    file.write_all("\n".as_bytes()).unwrap();
-}
-
-fn delete_log_files() -> std::io::Result<()> {
-    std::fs::remove_dir_all("/tmp/mosaic-logs").ok();
-    std::fs::create_dir_all("/tmp/mosaic-logs").ok();
-    Ok(())
-}
-
 pub fn main() {
     let opts = Opt::from_args();
     if opts.split.is_some() {
         match opts.split {
             Some('h') => {
-                let mut stream = UnixStream::connect("/tmp/mosaic").unwrap();
+                let mut stream = UnixStream::connect(MOSAIC_TMP_FOLDER).unwrap();
                 let api_command = bincode::serialize(&ApiCommand::SplitHorizontally).unwrap();
                 stream.write_all(&api_command).unwrap();
             }
             Some('v') => {
-                let mut stream = UnixStream::connect("/tmp/mosaic").unwrap();
+                let mut stream = UnixStream::connect(MOSAIC_TMP_FOLDER).unwrap();
                 let api_command = bincode::serialize(&ApiCommand::SplitVertically).unwrap();
                 stream.write_all(&api_command).unwrap();
             }
             _ => {}
         };
     } else if opts.move_focus {
-        let mut stream = UnixStream::connect("/tmp/mosaic").unwrap();
+        let mut stream = UnixStream::connect(MOSAIC_TMP_FOLDER).unwrap();
         let api_command = bincode::serialize(&ApiCommand::MoveFocus).unwrap();
         stream.write_all(&api_command).unwrap();
     } else if opts.open_file.is_some() {
-        let mut stream = UnixStream::connect("/tmp/mosaic").unwrap();
+        let mut stream = UnixStream::connect(MOSAIC_TMP_FOLDER).unwrap();
         let file_to_open = opts.open_file.unwrap();
         let api_command = bincode::serialize(&ApiCommand::OpenFile(file_to_open)).unwrap();
         stream.write_all(&api_command).unwrap();
@@ -109,7 +92,8 @@ pub enum AppInstruction {
 pub fn start(mut os_input: Box<dyn OsApi>, opts: Opt) {
     let mut active_threads = vec![];
 
-    delete_log_files().unwrap();
+    delete_log_dir().unwrap();
+    delete_log_file().unwrap();
 
     let full_screen_ws = os_input.get_terminal_size_using_fd(0);
     os_input.into_raw_mode(0);
@@ -335,7 +319,7 @@ pub fn start(mut os_input: Box<dyn OsApi>, opts: Opt) {
                     let mut buffer = [0; 10]; // TODO: more accurately
                     stdin.read(&mut buffer).expect("failed to read stdin");
                     // uncomment this to print the entered character to a log file (/tmp/mosaic-log.txt) for debugging
-                    // _debug_log_to_file(format!("buffer {:?}", buffer));
+                    //crate::utils::logging::debug_log_to_file(format!("buffer {:?}", buffer));
                     match buffer {
                         [10, 0, 0, 0, 0, 0, 0, 0, 0, 0] => {
                             // ctrl-j
diff --git a/src/os_input_output.rs b/src/os_input_output.rs
index 251b8c5e..ecd18edc 100644
--- a/src/os_input_output.rs
+++ b/src/os_input_output.rs
@@ -58,18 +58,6 @@ pub fn set_terminal_size_using_fd(fd: RawFd, columns: u16, rows: u16) {
     unsafe { ioctl(fd, TIOCSWINSZ.into(), &winsize) };
 }
 
-fn _debug_log_to_file(message: String) {
-    use std::fs::OpenOptions;
-    use std::io::prelude::*;
-    let mut file = OpenOptions::new()
-        .append(true)
-        .create(true)
-        .open("/tmp/mosaic-log.txt")
-        .unwrap();
-    file.write_all(message.as_bytes()).unwrap();
-    file.write_all("\n".as_bytes()).unwrap();
-}
-
 fn handle_command_exit(mut child: Child) {
     let signals = ::signal_hook::iterator::Signals::new(&[::signal_hook::SIGINT]).unwrap();
     'handle_exit: loop {
diff --git a/src/pty_bus.rs b/src/pty_bus.rs
index fed8f7f7..49334736 100644
--- a/src/pty_bus.rs
+++ b/src/pty_bus.rs
@@ -11,6 +11,7 @@ use std::path::PathBuf;
 
 use crate::layout::Layout;
 use crate::os_input_output::OsApi;
+use crate::utils::logging::debug_to_file;
 use crate::ScreenInstruction;
 
 pub struct ReadFromPid {
@@ -27,38 +28,6 @@ impl ReadFromPid {
     }
 }
 
-fn _debug_log_to_file(message: String) {
-    use std::fs::OpenOptions;
-    use std::io::prelude::*;
-    let mut file = OpenOptions::new()
-        .append(true)
-        .create(true)
-        .open("/tmp/mosaic-log.txt")
-        .unwrap();
-    file.write_all(message.as_bytes()).unwrap();
-    file.write_all("\n".as_bytes()).unwrap();
-}
-
-fn debug_to_file(message: u8, pid: RawFd) {
-    use std::fs::OpenOptions;
-    use std::io::prelude::*;
-    let mut path = PathBuf::new();
-    path.push(
-        [
-            String::from("/tmp/mosaic-logs/mosaic-"),
-            pid.to_string(),
-            String::from(".log"),
-        ]
-        .concat(),
-    );
-    let mut file = OpenOptions::new()
-        .append(true)
-        .create(true)
-        .open(path)
-        .unwrap();
-    file.write_all(&[message]).unwrap();
-}
-
 impl Stream for ReadFromPid {
     type Item = Vec<u8>;
     fn poll_next(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
@@ -208,7 +177,7 @@ fn stream_terminal_bytes(
                 let bytes_is_empty = bytes.is_empty();
                 for byte in bytes {
                     if debug {
-                        debug_to_file(byte, pid);
+                        debug_to_file(byte, pid).unwrap();
                     }
                     vte_parser.advance(&mut vte_event_sender, byte);
                 }
diff --git a/src/screen.rs b/src/screen.rs
index cf67909c..76c7b182 100644
--- a/src/screen.rs
+++ b/src/screen.rs
@@ -19,19 +19,7 @@ use crate::AppInstruction;
  *
  */
 
-fn _debug_log_to_file(message: String) {
-    use std::fs::OpenOptions;
-    use std::io::prelude::*;
-    let mut file = OpenOptions::new()
-        .append(true)
-        .create(true)
-        .open("/tmp/mosaic-log.txt")
-        .unwrap();
-    file.write_all(message.as_bytes()).unwrap();
-    file.write_all("\n".as_bytes()).unwrap();
-}
-
-const CURSOR_HEIGHT_WIDGH_RATIO: usize = 4; // this is not accurate and kind of a magic number, TODO: look into this
+const CURSOR_HEIGHT_WIDTH_RATIO: usize = 4; // this is not accurate and kind of a magic number, TODO: look into this
 
 type BorderAndPaneIds = (usize, Vec<RawFd>);
 
@@ -206,7 +194,7 @@ impl Screen {
                 (0, 0),
                 |(current_longest_edge, current_terminal_id_to_split), id_and_terminal_to_check| {
                     let (id_of_terminal_to_check, terminal_to_check) = id_and_terminal_to_check;
-                    let terminal_size = (terminal_to_check.get_rows() * CURSOR_HEIGHT_WIDGH_RATIO)
+                    let terminal_size = (terminal_to_check.get_rows() * CURSOR_HEIGHT_WIDTH_RATIO)
                         * terminal_to_check.get_columns();
                     if terminal_size > current_longest_edge {
                         (terminal_size, *id_of_terminal_to_check)
@@ -222,7 +210,7 @@ impl Screen {
                 ws_xpixel: terminal_to_split.get_x() as u16,
                 ws_ypixel: terminal_to_split.get_y() as u16,
             };
-            if terminal_to_split.get_rows() * CURSOR_HEIGHT_WIDGH_RATIO
+            if terminal_to_split.get_rows() * CURSOR_HEIGHT_WIDTH_RATIO
                 > terminal_to_split.get_columns()
             {
                 let (top_winsize, bottom_winsize) = split_horizontally_with_gap(&terminal_ws);
diff --git a/src/terminal_pane/scroll.rs b/src/terminal_pane/scroll.rs
index 3ced3828..5884ea32 100644
--- a/src/terminal_pane/scroll.rs
+++ b/src/terminal_pane/scroll.rs
@@ -26,18 +26,6 @@ pub struct CanonicalLine {
     pub wrapped_fragments: Vec<WrappedFragment>,
 }
 
-fn debug_log_to_file(message: String) {
-    use std::fs::OpenOptions;
-    use std::io::prelude::*;
-    let mut file = OpenOptions::new()
-        .append(true)
-        .create(true)
-        .open("/tmp/mosaic-log.txt")
-        .unwrap();
-    file.write_all(message.as_bytes()).unwrap();
-    file.write_all("\n".as_bytes()).unwrap();
-}
-
 impl CanonicalLine {
     pub fn new() -> Self {
         CanonicalLine {
@@ -163,6 +151,9 @@ impl CursorPosition {
     pub fn move_to_next_canonical_line(&mut self) {
         self.line_index.0 += 1;
     }
+    pub fn move_to_prev_canonical_line(&mut self) {
+        self.line_index.0 -= 1;
+    }
     pub fn move_to_beginning_of_linewrap(&mut self) {
         self.column_index = 0;
     }
@@ -307,8 +298,7 @@ impl Scroll {
             }
         }
         if current_canonical_line_index == self.canonical_lines.len() - 1 {
-            let new_canonical_line = CanonicalLine::new();
-            self.canonical_lines.push(new_canonical_line);
+            self.canonical_lines.push(CanonicalLine::new());
             self.cursor_position.move_to_next_canonical_line();
             self.cursor_position.move_to_beginning_of_canonical_line();
         } else if current_canonical_line_index < self.canonical_lines.len() - 1 {
@@ -517,6 +507,46 @@ impl Scroll {
             }
         }
     }
+    /// [scroll_up](https://github.com/alacritty/alacritty/blob/ec42b42ce601808070462111c0c28edb0e89babb/alacritty_terminal/src/grid/mod.rs#L261)
+    /// This function takes the first line of the scroll region and moves it to the bottom (count times)
+    pub fn rotate_scroll_region_up(&mut self, count: usize) {
+        if let Some((_, scroll_region_bottom)) = self.scroll_region {
+            if self.show_cursor {
+                let scroll_region_bottom_index = scroll_region_bottom - 1;
+                self.cursor_position
+                    .move_to_canonical_line(scroll_region_bottom_index);
+
+                let new_empty_lines = vec![CanonicalLine::new(); count];
+                self.canonical_lines.splice(
+                    scroll_region_bottom_index..scroll_region_bottom_index + 1,
+                    new_empty_lines,
+                );
+
+                self.cursor_position
+                    .move_to_canonical_line(scroll_region_bottom_index + count);
+            }
+        }
+    }
+    /// [scroll_down](https://github.com/alacritty/alacritty/blob/ec42b42ce601808070462111c0c28edb0e89babb/alacritty_terminal/src/grid/mod.rs#L221)
+    /// This function takes the last line of the scroll region and moves it to the top (count times)
+    pub fn rotate_scroll_region_down(&mut self, count: usize) {
+        if let Some((scroll_region_top, _)) = self.scroll_region {
+            if self.show_cursor {
+                let scroll_region_top_index = scroll_region_top - 1;
+                self.cursor_position
+                    .move_to_canonical_line(scroll_region_top_index);
+
+                let new_empty_lines = vec![CanonicalLine::new(); count];
+                self.canonical_lines.splice(
+                    scroll_region_top_index..scroll_region_top_index,
+                    new_empty_lines,
+                );
+
+                self.cursor_position
+                    .move_to_canonical_line(scroll_region_top_index + count);
+            }
+        }
+    }
     pub fn move_viewport_up(&mut self, count: usize) {
         if let Some(current_offset) = self.viewport_bottom_offset.as_mut() {
             *current_offset += count;
diff --git a/src/terminal_pane/terminal_pane.rs b/src/terminal_pane/terminal_pane.rs
index fc1cc207..bdaf6417 100644
--- a/src/terminal_pane/terminal_pane.rs
+++ b/src/terminal_pane/terminal_pane.rs
@@ -7,6 +7,7 @@ use crate::terminal_pane::terminal_character::{
     AnsiCode, CharacterStyles, NamedColor, TerminalCharacter,
 };
 use crate::terminal_pane::Scroll;
+use crate::utils::logging::{debug_log_to_file, debug_log_to_file_pid_0};
 use crate::VteEvent;
 
 #[derive(Clone, Copy, Debug)]
@@ -61,11 +62,14 @@ impl TerminalPane {
             position_and_size_override: None,
         }
     }
+    pub fn mark_for_rerender(&mut self) {
+        self.should_render = true;
+    }
     pub fn handle_event(&mut self, event: VteEvent) {
         match event {
             VteEvent::Print(c) => {
                 self.print(c);
-                self.should_render = true;
+                self.mark_for_rerender();
             }
             VteEvent::Execute(byte) => {
                 self.execute(byte);
@@ -95,57 +99,57 @@ impl TerminalPane {
         self.position_and_size.x += count;
         self.position_and_size.columns -= count;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn reduce_width_left(&mut self, count: usize) {
         self.position_and_size.columns -= count;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn increase_width_left(&mut self, count: usize) {
         self.position_and_size.x -= count;
         self.position_and_size.columns += count;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn increase_width_right(&mut self, count: usize) {
         self.position_and_size.columns += count;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn reduce_height_down(&mut self, count: usize) {
         self.position_and_size.y += count;
         self.position_and_size.rows -= count;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn increase_height_down(&mut self, count: usize) {
         self.position_and_size.rows += count;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn increase_height_up(&mut self, count: usize) {
         self.position_and_size.y -= count;
         self.position_and_size.rows += count;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn reduce_height_up(&mut self, count: usize) {
         self.position_and_size.rows -= count;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn change_size_p(&mut self, position_and_size: &PositionAndSize) {
         self.position_and_size = *position_and_size;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     // TODO: merge these two methods
     pub fn change_size(&mut self, ws: &Winsize) {
         self.position_and_size.columns = ws.ws_col as usize;
         self.position_and_size.rows = ws.ws_row as usize;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn get_x(&self) -> usize {
         match self.position_and_size_override {
@@ -210,7 +214,7 @@ impl TerminalPane {
                 }
                 character_styles.clear();
             }
-            self.should_render = false;
+            self.mark_for_rerender();
             Some(vte_output)
         } else {
             None
@@ -225,15 +229,23 @@ impl TerminalPane {
     }
     pub fn scroll_up(&mut self, count: usize) {
         self.scroll.move_viewport_up(count);
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn scroll_down(&mut self, count: usize) {
         self.scroll.move_viewport_down(count);
-        self.should_render = true;
+        self.mark_for_rerender();
+    }
+    pub fn rotate_scroll_region_up(&mut self, count: usize) {
+        self.scroll.rotate_scroll_region_up(count);
+        self.mark_for_rerender();
+    }
+    pub fn rotate_scroll_region_down(&mut self, count: usize) {
+        self.scroll.rotate_scroll_region_down(count);
+        self.mark_for_rerender();
     }
     pub fn clear_scroll(&mut self) {
         self.scroll.reset_viewport();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn override_size_and_position(&mut self, x: usize, y: usize, size: &Winsize) {
         let position_and_size_override = PositionAndSize {
@@ -244,17 +256,17 @@ impl TerminalPane {
         };
         self.position_and_size_override = Some(position_and_size_override);
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     pub fn reset_size_and_position_override(&mut self) {
         self.position_and_size_override = None;
         self.reflow_lines();
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     fn add_newline(&mut self) {
         self.scroll.add_canonical_line();
         // self.reset_all_ansi_codes(); // TODO: find out if we should be resetting here or not
-        self.should_render = true;
+        self.mark_for_rerender();
     }
     fn move_to_beginning_of_line(&mut self) {
         self.scroll.move_cursor_to_beginning_of_linewrap();
@@ -267,20 +279,6 @@ impl TerminalPane {
     }
 }
 
-fn debug_log_to_file(message: String, pid: RawFd) {
-    if pid == 3 {
-        use std::fs::OpenOptions;
-        use std::io::prelude::*;
-        let mut file = OpenOptions::new()
-            .append(true)
-            .create(true)
-            .open("/tmp/mosaic-log.txt")
-            .unwrap();
-        file.write_all(message.as_bytes()).unwrap();
-        file.write_all("\n".as_bytes()).unwrap();
-    }
-}
-
 impl vte::Perform for TerminalPane {
     fn print(&mut self, c: char) {
         // apparently, building TerminalCharacter like this without a "new" method
@@ -632,7 +630,8 @@ impl vte::Perform for TerminalPane {
                     .pending_styles
                     .background(Some(AnsiCode::NamedColor(NamedColor::White)));
             } else {
-                debug_log_to_file(format!("unhandled csi m code {:?}", params), self.pid);
+                debug_log_to_file_pid_0(format!("unhandled csi m code {:?}", params), self.pid)
+                    .unwrap();
             }
         } else if c == 'C' {
             // move cursor forward
@@ -685,7 +684,7 @@ impl vte::Perform for TerminalPane {
                 match params.get(0) {
                     Some(25) => {
                         self.scroll.hide_cursor();
-                        self.should_render = true;
+                        self.mark_for_rerender();
                     }
                     _ => {}
                 };
@@ -700,7 +699,7 @@ impl vte::Perform for TerminalPane {
                 match params.get(0) {
                     Some(25) => {
                         self.scroll.show_cursor();
-                        self.should_render = true;
+                        self.mark_for_rerender();
                     }
                     _ => {}
                 };
@@ -741,8 +740,38 @@ impl vte::Perform for TerminalPane {
                 .add_empty_lines_in_scroll_region(line_count_to_add);
         } else if c == 'q' || c == 'd' || c == 'X' || c == 'G' {
             // ignore for now to run on mac
+        } else if c == 'T' {
+            /*
+             * 124  54  T   SD
+             * Scroll down, new lines inserted at top of screen
+             * [4T = Scroll down 4, bring previous lines back into view
+             */
+            debug_log_to_file(format!(
+                "htop (only?) linux csi: {}->{:?} ({:?} - ignore: {})",
+                c, params, _intermediates, _ignore
+            ))
+            .unwrap();
+            let line_count: i64 = *params.get(0).expect("A number of lines was expected.");
+
+            if line_count >= 0 {
+                self.rotate_scroll_region_up(line_count as usize);
+            } else {
+                self.rotate_scroll_region_down(line_count.abs() as usize);
+            }
+        } else if c == 'P' {
+            /*
+             * 120 50 P * DCH
+             * Delete Character, from current position to end of field
+             * [4P = Delete 4 characters, VT102 series
+             */
+            debug_log_to_file(format!(
+                "htop (only?) linux csi: {}->{:?} (intermediates: {:?}, ignore: {})",
+                c, params, _intermediates, _ignore
+            ))
+            .unwrap();
         } else {
-            panic!("unhandled csi: {:?}->{:?}", c, params);
+            debug_log_to_file(format!("Unhandled csi: {}->{:?}", c, params)).unwrap();
+            panic!("unhandled csi: {}->{:?}", c, params);
         }
     }
 
diff --git a/src/utils/consts.rs b/src/utils/consts.rs
new file mode 100644
index 00000000..5eb96c67
--- /dev/null
+++ b/src/utils/consts.rs
@@ -0,0 +1,3 @@
+pub const MOSAIC_TMP_LOG_FILE: &str = "/tmp/mosaic-log.txt";
+pub const MOSAIC_TMP_LOG_DIR: &str = "/tmp/mosaic-log";
+pub const MOSAIC_TMP_FOLDER: &str = "/tmp/mosaic";
diff --git a/src/utils/logging.rs b/src/utils/logging.rs
new file mode 100644
index 00000000..77e924a9
--- /dev/null
+++ b/src/utils/logging.rs
@@ -0,0 +1,58 @@
+use std::{
+    fs,
+    io::{self, prelude::*},
+    os::unix::io::RawFd,
+    path::PathBuf,
+};
+
+use crate::utils::consts::{MOSAIC_TMP_LOG_DIR, MOSAIC_TMP_LOG_FILE};
+
+pub fn debug_log_to_file(message: String) -> io::Result<()> {
+    let mut file = fs::OpenOptions::new()
+        .append(true)
+        .create(true)
+        .open(MOSAIC_TMP_LOG_FILE)?;
+    file.write_all(message.as_bytes())?;
+    file.write_all("\n".as_bytes())?;
+
+    Ok(())
+}
+
+pub fn debug_log_to_file_pid_0(message: String, pid: RawFd) -> io::Result<()> {
+    if pid == 0 {
+        debug_log_to_file(message)?;
+    }
+
+    Ok(())
+}
+
+pub fn delete_log_file() -> io::Result<()> {
+    if fs::metadata(MOSAIC_TMP_LOG_FILE).is_ok() {
+        fs::remove_file(MOSAIC_TMP_LOG_FILE)?;
+    }
+
+    Ok(())
+}
+
+pub fn delete_log_dir() -> io::Result<()> {
+    if fs::metadata(MOSAIC_TMP_LOG_DIR).is_ok() {
+        fs::remove_dir_all(MOSAIC_TMP_LOG_DIR)?;
+    }
+    fs::create_dir_all(MOSAIC_TMP_LOG_DIR)?;
+
+    Ok(())
+}
+
+pub fn debug_to_file(message: u8, pid: RawFd) -> io::Result<()> {
+    let mut path = PathBuf::new();
+    path.push(MOSAIC_TMP_LOG_DIR);
+    path.push(format!("mosaic-{}.log", pid.to_string()));
+
+    let mut file = fs::OpenOptions::new()
+        .append(true)
+        .create(true)
+        .open(path)?;
+    file.write_all(&[message])?;
+
+    Ok(())
+}
diff --git a/src/utils/mod.rs b/src/utils/mod.rs
new file mode 100644
index 00000000..140eec18
--- /dev/null
+++ b/src/utils/mod.rs
@@ -0,0 +1,2 @@
+pub mod consts;
+pub mod logging;