feat: handle suspend signal

Cargo.toml

@@ -35,6 +35,7 @@ console = "0.15.8"
 thiserror = "1"
 unicode-width = "0.1"
 os_pipe = "1.1.5"
+libc = "0.2.155"
 
 [dependencies.syntect]
 version = "5.2"

config-file-schema.json

@@ -194,6 +194,13 @@
             "$ref": "#/definitions/KeyBinding"
           }
         },
+        "suspend": {
+          "description": "The key binding to suspend the application.",
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/KeyBinding"
+          }
+        },
         "toggle_bindings": {
           "description": "The key binding to toggle the key bindings modal.",
           "type": "array",

config.sample.yaml

@@ -1,3 +1,4 @@
+---
 # yaml-language-server: $schema=https://raw.githubusercontent.com/mfontanini/presenterm/master/config-file-schema.json
 defaults:
   # override the terminal font size when in windows or when using sixel.
@@ -83,3 +84,6 @@ bindings:
 
   # the key binding to close the application.
   exit: ["<c-c>", "q"]
+
+  # the key binding to suspend the application.
+  suspend: ["<c-z>"]

src/custom.rs

@@ -330,6 +330,10 @@ pub struct KeyBindingsConfig {
     /// The key binding to close the application.
     #[serde(default = "default_exit_bindings")]
     pub(crate) exit: Vec<KeyBinding>,
+
+    /// The key binding to suspend the application.
+    #[serde(default = "default_suspend_bindings")]
+    pub(crate) suspend: Vec<KeyBinding>,
 }
 
 impl Default for KeyBindingsConfig {
@@ -348,6 +352,7 @@ impl Default for KeyBindingsConfig {
             toggle_bindings: default_toggle_bindings_modal_bindings(),
             close_modal: default_close_modal_bindings(),
             exit: default_exit_bindings(),
+            suspend: default_suspend_bindings(),
         }
     }
 }
@@ -412,6 +417,10 @@ fn default_exit_bindings() -> Vec<KeyBinding> {
     make_keybindings(["<c-c>", "q"])
 }
 
+fn default_suspend_bindings() -> Vec<KeyBinding> {
+    make_keybindings(["<c-z>"])
+}
+
 #[cfg(test)]
 mod test {
     use super::*;

src/input/source.rs

@@ -74,6 +74,9 @@ pub(crate) enum Command {
     /// Exit the presentation.
     Exit,
 
+    /// Suspend the presentation.
+    Suspend,
+
     /// The presentation has changed and needs to be reloaded.
     Reload,
 

src/input/user.rs

@@ -90,6 +90,7 @@ impl CommandKeyBindings {
             }
             RenderAsyncOperations => Command::RenderAsyncOperations,
             Exit => Command::Exit,
+            Suspend => Command::Suspend,
             Reload => Command::Reload,
             HardReload => Command::HardReload,
             ToggleSlideIndex => Command::ToggleSlideIndex,
@@ -133,6 +134,7 @@ impl TryFrom<KeyBindingsConfig> for CommandKeyBindings {
             .chain(zip(CommandDiscriminants::LastSlide, config.last_slide))
             .chain(zip(CommandDiscriminants::GoToSlide, config.go_to_slide))
             .chain(zip(CommandDiscriminants::Exit, config.exit))
+            .chain(zip(CommandDiscriminants::Suspend, config.suspend))
             .chain(zip(CommandDiscriminants::HardReload, config.reload))
             .chain(zip(CommandDiscriminants::ToggleSlideIndex, config.toggle_slide_index))
             .chain(zip(CommandDiscriminants::ToggleKeyBindingsConfig, config.toggle_bindings))

src/presenter.rs

@@ -112,6 +112,10 @@ impl<'a> Presenter<'a> {
                 };
                 match self.apply_command(command) {
                     CommandSideEffect::Exit => return Ok(()),
+                    CommandSideEffect::Suspend => {
+                        self.suspend(&mut drawer);
+                        break;
+                    }
                     CommandSideEffect::Reload => {
                         self.try_reload(path, false);
                         break;
@@ -196,6 +200,7 @@ impl<'a> Presenter<'a> {
                 return CommandSideEffect::Reload;
             }
             Command::Exit => return CommandSideEffect::Exit,
+            Command::Suspend => return CommandSideEffect::Suspend,
             _ => (),
         };
         if matches!(command, Command::Redraw) {
@@ -245,7 +250,7 @@ impl<'a> Presenter<'a> {
                 true
             }
             // These are handled above as they don't require the presentation
-            Command::Reload | Command::HardReload | Command::Exit | Command::Redraw => {
+            Command::Reload | Command::HardReload | Command::Exit | Command::Suspend | Command::Redraw => {
                 panic!("unreachable commands")
             }
         };
@@ -348,10 +353,20 @@ impl<'a> Presenter<'a> {
             other => self.state = other,
         }
     }
+
+    fn suspend(&self, drawer: &mut TerminalDrawer<Stdout>) {
+        drawer.terminal.suspend();
+        #[cfg(unix)]
+        unsafe {
+            libc::raise(libc::SIGTSTP);
+        }
+        drawer.terminal.resume();
+    }
 }
 
 enum CommandSideEffect {
     Exit,
+    Suspend,
     Redraw,
     Reload,
     None,

src/render/draw.rs

@@ -17,7 +17,7 @@ pub(crate) type RenderResult = Result<(), RenderError>;
 
 /// Allows drawing elements in the terminal.
 pub(crate) struct TerminalDrawer<W: TerminalWrite> {
-    terminal: Terminal<W>,
+    pub(crate) terminal: Terminal<W>,
     font_size_fallback: u8,
 }
 

src/render/terminal.rs

@@ -110,6 +110,14 @@ impl<W: TerminalWrite> Terminal<W> {
         self.cursor_row += options.rows;
         Ok(())
     }
+
+    pub(crate) fn suspend(&mut self) {
+        self.writer.deinit();
+    }
+
+    pub(crate) fn resume(&mut self) {
+        let _ = self.writer.init();
+    }
 }
 
 impl<W> Drop for Terminal<W>