docs

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Cargo.toml

@@ -1,9 +1,18 @@
 [package]
 name = "swayout"
-version = "0.1.0"
+version = "1.2.2"
 edition = "2021"
+description = "A tool to configure sway outputs"
+authors = ["Stephen Byrne"]
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-json = "0.12.4"
+# for json output from swaymsg
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0.133"
+
+# for config file
+kdl = "6.1.0"
+
+xdg = "2.5.2"

README.md

@@ -0,0 +1,62 @@
+# swayout
+
+`swayout` is a utility to configure [sway](https://swaywm.org/) outputs.
+
+[kanshi](https://sr.ht/~emersion/kanshi/) and [way-displays](https://github.com/alex-courtis/way-displays) certainly
+do a better job of this. I wrote this because I wanted a project to learn Rust.
+
+Monitors and layouts are configured in a [KDL](https://kdl.dev) file
+(`~/.config/swayout/config.kdl`).
+
+Example `config.kdl`:
+
+```kdl
+// This is my laptop's built-in screen.
+monitor "laptop" make="Unknown" model="0x403D" serial="0x00000000" lid="LID"
+
+// I usually have it hooked up to this monitor, which is the top one on my desk.
+monitor "top" make="Dell Inc." model="DELL U2415" serial="CFV9N99T0Y0U"
+
+// Sometimes I hook it up to these monitors, which are left and right.
+// The left is in portrait.
+monitor "left" make="Goldstar Company Ltd" model="LG HDR 4K" serial="0x0000B9C0"
+monitor "right" make="Goldstar Company Ltd" model="LG HDR 4K" serial="0x0000B9BF"
+
+// When I have "left" and "right" hooked up, I want this layout.
+layout "two4k" automatic=#true {
+    output "left" mode="3840x2160" scale="1.5" x=0 y=0 transform="270"
+    output "right" mode="3840x2160" scale="1.5" x=1440 y=1120 transform="normal"
+}
+```
+
+When you run `swayout`, it prints all available layout names to standard output, one per line.
+Printed layouts include:
+
+* All layouts defined in `config.kdl` for which the monitors are currently available. E.g.: `two4k`.
+* All monitors defined in `config.kdl` that are currently available. E.g.: `laptop`, `left`, `right`.
+* All available outputs that are not matched by a configured monitor. E.g.: `HDMI-2`.
+ 
+If a monitor has its `lid` property is set to the name of a directory in `/proc/acpi/button/lid/`, if the `state` file
+in that directory indicates that the lid is closed, the monitor will not be considered available.
+
+If you pass a layout name (or monitor name, or output name) as a command line argument to `swayout`,
+it calls `swaymsg` to configure that layout.
+If a monitor name or output name is passed, only that monitor or output is enabled, and the output's defaults are used.
+
+This behavior is useful in conjunction with [tofi](https://github.com/philj56/tofi).
+My sway configuration has:
+
+```
+set $select_layout swayout | tofi | xargs swayout
+bindsym $mod+Shift+m exec $select_layout
+```
+
+If `swayout` is called with the `--automatic` switch, the first layout with `automatic=#true` for which all outputs
+are available is enabled. If no automatic layouts are available, `swayout` exits with code 2.
+
+This could be run by `bindswitch lid:toggle exec swayout --automatic`.
+
+## TODO
+
+How to call when an output is connected or disconnected?
+Wayland events via [wayland_client](https://docs.rs/wayland-client/latest/wayland_client/index.html)?

src/config.rs

@@ -0,0 +1,119 @@
+use kdl::KdlDocument;
+use std::collections::HashMap;
+use std::fs;
+
+/// Configuration for swayout.
+pub struct Config {
+    /// Monitor name is independent of output name. It can be anything.
+    pub monitors: Vec<Monitor>,
+    /// Definition of layouts: a map of the layout name to the outputs.
+    /// The outputs is a map of the monitor name (in `monitors`) to the configuration
+    /// of that monitor for this layout.
+    /// Available outputs that do not match a monitor in the map are disabled.
+    pub layouts: Vec<Layout>,
+}
+
+/// A configured layout
+pub struct Layout {
+    /// Layout name
+    pub name: String,
+    /// If true, automatically enableable
+    pub automatic: bool,
+    /// Map of monitor name to OutputConfig
+    pub outputs: HashMap<String, OutputConfig>,
+}
+
+/// Defines a monitor by make, model, and serial.
+pub struct Monitor {
+    pub name: String,
+    pub make: String,
+    pub model: String,
+    pub serial: String,
+    pub lid: Option<String>,
+}
+
+/// Configuration for an enabled output.
+pub struct OutputConfig {
+    /// mode. See man 5 sway-output
+    pub mode: String,
+    /// scale. See man 5 sway-output
+    pub scale: String,
+    /// x value for position. See man 5 sway-output
+    pub x: u16,
+    /// y value for position. See man 5 sway-output
+    pub y: u16,
+    /// transform. See man 5 sway-output
+    pub transform: String,
+}
+
+/// Get a `Config` from ~/.config/swayout/config.kdl.
+/// (It really uses XDG config dirs.)
+pub fn get_config() -> Config {
+    let xdg_dirs = xdg::BaseDirectories::with_prefix("swayout").unwrap();
+    if let Some(path) = xdg_dirs.find_config_file("config.kdl") {
+        let kdl = fs::read_to_string(path).expect("error reading file");
+        parse_config(kdl)
+    } else {
+        // no config files, use an empty rules
+        Config {
+            monitors: Vec::new(),
+            layouts: Vec::new(),
+        }
+    }
+}
+fn parse_config(kdl: String) -> Config {
+    let doc: KdlDocument = kdl.parse().expect("failed to parse config KDL");
+
+    let monitors: Vec<Monitor> = doc
+        .nodes()
+        .iter()
+        .filter(|node| node.name().value() == "monitor")
+        .map(|monitor_node| Monitor {
+            name: String::from(monitor_node[0].as_string().unwrap()),
+            make: String::from(monitor_node["make"].as_string().unwrap()),
+            model: String::from(monitor_node["model"].as_string().unwrap()),
+            serial: String::from(monitor_node["serial"].as_string().unwrap()),
+            lid: if let Some(lid) = monitor_node.get("lid") {
+                Some(String::from(lid.as_string().unwrap()))
+            } else {
+                None
+            },
+        })
+        .collect();
+
+    let layouts: Vec<Layout> = doc
+        .nodes()
+        .iter()
+        .filter(|node| node.name().value() == "layout")
+        .map(|layout_node| {
+            let name = String::from(layout_node[0].as_string().unwrap());
+            let automatic = layout_node
+                .get("automatic")
+                .is_some_and(|v| v.as_bool().is_some_and(|a| a));
+            let outputs: HashMap<String, OutputConfig> = layout_node
+                .children()
+                .unwrap()
+                .nodes()
+                .iter()
+                .map(|output_node| {
+                    let output = String::from(output_node[0].as_string().unwrap());
+                    let output_config = OutputConfig {
+                        mode: String::from(output_node["mode"].as_string().unwrap()),
+                        scale: String::from(output_node["scale"].as_string().unwrap()),
+                        transform: String::from(output_node["transform"].as_string().unwrap()),
+                        x: output_node["x"].as_integer().unwrap() as u16,
+                        y: output_node["y"].as_integer().unwrap() as u16,
+                    };
+                    (output, output_config)
+                })
+                .collect();
+            Layout {
+                name,
+                automatic,
+                outputs,
+            }
+        })
+        .collect();
+
+    Config { monitors, layouts }
+}

src/lib.rs

@@ -0,0 +1,242 @@
+use std::collections::{HashMap, HashSet};
+
+mod config;
+use crate::config::{get_config, Config, Layout, Monitor, OutputConfig};
+
+mod lid;
+use crate::lid::is_lid_closed;
+
+mod sway;
+use crate::sway::{apply_outputs, get_outputs, Output};
+
+/// Determine the available layout names.
+/// Return one layout for each layout defined in the configuration file
+/// for which all outputs are available (and lids are not closed),
+/// one for each monitor defined in the configuration file (for using just that monitor) if the lid is not closed,
+/// and one for each available output that is not a configured monitor (for using just that output).
+fn get_layouts() -> HashSet<String> {
+    let outputs = get_outputs();
+
+    let config = get_config();
+    let monitor_states = get_monitor_states(&config, &outputs);
+
+    let mut layout_names: HashSet<String> = HashSet::new();
+
+    // Add each layout defined in the config file for which all outputs are available
+    get_available_layouts(&config, &monitor_states)
+        .iter()
+        .for_each(|layout| {
+            layout_names.insert(String::from(&layout.name));
+        });
+
+    // add each individual output (by monitor name if the monitor is defined, else by output name)
+    outputs.iter().for_each(|output| {
+        // if there is a monitor for the output, use the monitor name, else use the output name
+        if let Some(monitor_state) = get_monitor_state_for_output(&monitor_states, &output) {
+            // do not include it if the lid is closed
+            if !monitor_state.is_lid_closed {
+                layout_names.insert(String::from(&monitor_state.monitor.name));
+            }
+        } else {
+            layout_names.insert(String::from(&output.name));
+        }
+    });
+
+    layout_names
+}
+
+/// Monitor and lid state. Created for available monitors.
+struct MonitorState<'a> {
+    monitor: &'a Monitor,
+    is_lid_closed: bool,
+}
+
+/// Get a MonitorState for each monitor that is available (matches an output).
+fn get_monitor_states<'a, 'b>(
+    config: &'a Config,
+    outputs: &'b Vec<Output>,
+) -> Vec<MonitorState<'a>> {
+    config
+        .monitors
+        .iter()
+        .filter(|monitor| {
+            outputs
+                .iter()
+                .any(|output| monitor_matches_output(&monitor, &output))
+        })
+        .map(|monitor| MonitorState {
+            monitor,
+            is_lid_closed: is_lid_closed(&monitor),
+        })
+        .collect()
+}
+
+/// Find a monitor state that matches the supplied output.
+fn get_monitor_state_for_output<'a, 'b>(
+    monitor_states: &'a Vec<MonitorState<'a>>,
+    output: &'b &Output,
+) -> Option<&'a MonitorState<'a>> {
+    monitor_states
+        .iter()
+        .find(|monitor_state| monitor_matches_output(monitor_state.monitor, output))
+}
+
+/// Determine if the specified monitor matches the specified output (by make/model/serial).
+fn monitor_matches_output(monitor: &Monitor, output: &Output) -> bool {
+    monitor.make == output.make && monitor.model == output.model && monitor.serial == output.serial
+}
+
+/// Find a monitor state by monitor name.
+fn get_monitor_state_by_name<'a, 'b>(
+    monitor_states: &'a Vec<MonitorState<'a>>,
+    monitor_name: &'b String,
+) -> Option<&'a MonitorState<'a>> {
+    monitor_states
+        .iter()
+        .find(|monitor_state| &monitor_state.monitor.name == monitor_name)
+}
+
+/// Determine if the specified monitor name is available:
+/// if it is one of the known monitors and the lid is not closed.
+fn is_monitor_available<'a, 'b>(
+    monitor_states: &'a Vec<MonitorState<'a>>,
+    monitor_name: &'b String,
+) -> bool {
+    if let Some(monitor_state) = get_monitor_state_by_name(&monitor_states, monitor_name) {
+        !monitor_state.is_lid_closed
+    } else {
+        false
+    }
+}
+
+/// Get the layouts for which all monitors are available and lids are not closed.
+fn get_available_layouts<'a, 'b, 'c>(
+    config: &'a Config,
+    monitor_states: &'a Vec<MonitorState<'a>>,
+) -> Vec<&'a Layout> {
+    config
+        .layouts
+        .iter()
+        .filter(|layout| {
+            layout.outputs.iter().all(|(monitor_name, _output_config)| {
+                is_monitor_available(monitor_states, monitor_name)
+            })
+        })
+        .collect()
+}
+
+/// Print the name of each layout to standard out, one per line
+pub fn print_layout_names() {
+    get_layouts().iter().for_each(|layout| println!("{layout}"))
+}
+
+/// Apply the specified layout.
+/// layout_name may be the name of a layout in the config, the name of a monitor,
+/// or the name of an output.
+/// Return true of any outputs were enabled.
+/// Return false if there were no outputs to enable and thus nothing was done.
+pub fn apply_layout(layout_name: &String) -> Result<(), String> {
+    let config = get_config();
+    let outputs = get_outputs();
+    let monitor_states = get_monitor_states(&config, &outputs);
+
+    // Map of output name to config for all outputs to enable.
+    // (All outputs not in this map will be disabled.)
+    let mut output_config_map: HashMap<&String, &OutputConfig> = HashMap::new();
+
+    // First check if the layout is defined in the rules
+    if let Some(layout) = config
+        .layouts
+        .iter()
+        .find(|layout| &layout.name == layout_name)
+    {
+        // The layout is defined in the config.
+        for (monitor_name, output_config) in &layout.outputs {
+            // there is probably a syntactic sugar for this?
+            let monitor_state = if let Some(monitor_state) =
+                get_monitor_state_by_name(&monitor_states, &monitor_name)
+            {
+                monitor_state
+            } else {
+                return Err(format!(
+                    "Cannot find monitor '{}' for layout '{}'",
+                    monitor_name, layout_name
+                ));
+            };
+
+            if monitor_state.is_lid_closed {
+                return Err(format!("Monitor '{}' is closed.", monitor_name));
+            }
+
+            // find the output for the monitor to get the output name.
+            let output_opt = outputs
+                .iter()
+                .find(|output| monitor_matches_output(monitor_state.monitor, output));
+            if let Some(output) = output_opt {
+                output_config_map.insert(&output.name, &output_config);
+            } else {
+                return Err(format!("Missing output for monitor '{}'.", monitor_name));
+            }
+        }
+    } else {
+        // The layout is not defined in the rules.
+        // See if it is a monitor name...
+        if let Some(monitor_state) = get_monitor_state_by_name(&monitor_states, &layout_name) {
+            if monitor_state.is_lid_closed {
+                return Err(format!(
+                    "Monitor '{}' is closed.",
+                    &monitor_state.monitor.name
+                ));
+            }
+
+            // It is a monitor name. Find the matching output...
+            if let Some(output) = outputs
+                .iter()
+                .find(|output| monitor_matches_output(monitor_state.monitor, output))
+            {
+                output_config_map.insert(&output.name, &output.output_config);
+            } else {
+                return Err(format!(
+                    "Could not find output for monitor '{}'.",
+                    layout_name
+                ));
+            }
+        } else {
+            // See if it is an output name...
+            if let Some(output) = outputs.iter().find(|output| &output.name == layout_name) {
+                output_config_map.insert(&output.name, &output.output_config);
+            } else {
+                return Err(format!(
+                    "Could not find layout, monitor, or output '{}.'",
+                    layout_name
+                ));
+            }
+        }
+    }
+
+    if output_config_map.is_empty() {
+        return Err("No outputs would be enabled. Do nothing.".to_string());
+    }
+
+    apply_outputs(&outputs, &output_config_map)
+}
+
+/// Apply the first automatic layout for which all outputs are available.
+/// Return the name of the layout applied or None if no automatic layout was available.
+pub fn apply_automatic() -> Result<String,String> {
+    let outputs = get_outputs();
+
+    let config = get_config();
+    let monitor_states = get_monitor_states(&config, &outputs);
+
+    if let Some(layout) = get_available_layouts(&config, &monitor_states)
+        .iter()
+        .find(|layout| layout.automatic)
+    {
+
+        apply_layout(&layout.name)?;
+        Ok(String::from(&layout.name))
+    } else {
+        Err("No automatic layouts available.".to_string())
+    }
+}

src/lid.rs

@@ -0,0 +1,48 @@
+use std::fs::File;
+use std::io::Read;
+use std::path::PathBuf;
+use crate::config::Monitor;
+
+// Determine if the lid id closed.
+// Returns true if the lid is known to be closed.
+// Returns false if the lid is known to be open, or if the lid state is not known.
+pub fn is_lid_closed(monitor: &Monitor) -> bool {
+    if let Some(lid) = &monitor.lid {
+        is_acpi_closed(lid)
+    } else {
+        false
+    }
+}
+
+/// Determine if the lid is closed.
+/// lid is the name of a directory in /proc/acpi/button/lid/.
+fn is_acpi_closed(lid: &String) -> bool {
+    let mut path_buf = PathBuf::from("/proc/acpi/button/lid");
+    path_buf.push(&lid);
+    path_buf.push("state");
+
+    if let Ok(ok) = path_buf.try_exists() {
+        if ok {
+            File::open(path_buf).is_ok_and(|mut file| {
+                let mut str = String::new();
+                if let Ok(_size) = file.read_to_string(&mut str) {
+                    is_state_closed(str)
+                } else {
+                    // error reading file
+                    false
+                }
+            })
+        } else {
+            // no file
+            false
+        }
+    } else {
+        // error checking for file
+        false
+    }
+}
+
+/// Parse a /proc/acpi/button/lid/*/state file and return true if the lid is closed
+fn is_state_closed(str:String) -> bool {
+    str.contains("closed")
+}

src/main.rs

@@ -1,95 +1,30 @@
-use std::process::Command;
-use std::str;
-use json;
-use json::JsonValue;
+use std::{env, process};
 
-enum SwayOutput {
-    Disabled {
-        name: String,
-    },
-    Enabled {
-        name: String,
-        width: i32,
-        height: i32,
-        x: i32,
-        y: i32,
-    }
-}
 fn main() {
-    let output = Command::new("swaymsg")
-                     .arg("-t")
-                     .arg("get_outputs")
-                     .output()
-                     .expect("Failed to execute command");
-    let s = str::from_utf8(&output.stdout).unwrap();
-
-    let mut outputs: Vec<SwayOutput> = Vec::new();
-
-    let json = json::parse(s).unwrap();
-
-    // TODO I think there is a better alternative syntax to match here.
-    let json_outputs =
-        if let JsonValue::Array(vec) = json {
-            vec
+    let args: Vec<String> = env::args().collect();
+    if args.len() == 1 {
+        // first arg is executable
+        swayout::print_layout_names();
+    } else if args.len() == 2 {
+        let arg = &args[1];
+        if arg == "--automatic" {
+            match swayout::apply_automatic() {
+                Ok(layout_name) => {
+                    println!("{}", layout_name);
+                }
+                Err(e) => {
+                    eprintln!("{}", e);
+                    process::exit(2)
+                }
+            }
         } else {
-            panic!("json is not an array");
-        };
-
-    let size = json_outputs.len();
-    if size == 1 {
-        // If there is 1 output, use it.
-        let json_output = &json_outputs[0];
-        let name = &json_output["name"];
-        let mode = &json_output["modes"][0];
-        outputs.push(SwayOutput::Enabled {
-            name: name.to_string(),
-            width: mode["width"].as_i32().unwrap(),
-            height: mode["height"].as_i32().unwrap(),
-            x: 0,
-            y: 0,
-        });
-    } else {
-        let dell_option:Option<&JsonValue> = json_outputs.iter()
-            .find( |json_output| json_output["serial"].to_string() == "CFV9N99T0Y0U");
-        if dell_option.is_some() {
-            // The Dell on my desk is attached. Use it, and disable others.
-            let dell = dell_option.unwrap();
-            outputs.push(SwayOutput::Enabled {
-                name: dell["name"].to_string(),
-                width: 1920,
-                height: 1200,
-                x: 0,
-                y: 0
-            });
-            json_outputs.iter()
-                .filter( |json_output| {
-                    json_output["serial"].to_string() != "CFV9N99T0Y0U"
-                })
-                .for_each( |json_output| {
-                    outputs.push(SwayOutput::Disabled {
-                        name: json_output["name"].to_string()
-                    });
-                });
-        } else {
-            println!("unknown state, do nothing")
-        }
-    }
-
-    // TODO do all enables then all disables.
-    // TODO if there are only disables then do nothing.
-    for output in &outputs {
-        match output {
-            SwayOutput::Disabled { name } => {
-                println!("swaymsg output {} disabled", name);
-                // TODO run
-            },
-            SwayOutput::Enabled { name, width, height, x, y } => {
-                println!(
-                    "swaymsg output {} enable dpms on mode {}x{} pos {} {}",
-                    name, width, height, x, y);
-                // TODO run
+            if let Err(e) = swayout::apply_layout(&args[1]) {
+                eprintln!("{}", e);
+                process::exit(3)
             }
         }
+    } else {
+        eprintln!("Usage: {} [layout]", args[0].as_str());
+        process::exit(1)
     }
-
 }

src/sway.rs

@@ -0,0 +1,125 @@
+use crate::config::OutputConfig;
+use serde_json::{from_str, Value};
+use std::collections::HashMap;
+use std::process::Command;
+use std::str::from_utf8;
+
+/// An output, as returned by `swaymsg -t get_outputs`.
+pub struct Output {
+    /// output name, according to sway
+    pub name: String,
+    pub make: String,
+    pub model: String,
+    pub serial: String,
+    pub output_config: OutputConfig,
+}
+
+/// Get all outputs currently available, according to `swaymsg -t get_outputs`.
+pub fn get_outputs() -> Vec<Output> {
+    let output = Command::new("swaymsg")
+        .arg("-t")
+        .arg("get_outputs")
+        .output()
+        .expect("swaymsg -t get_outputs failed");
+    let json_string = from_utf8(&output.stdout).unwrap();
+    let json = from_str(json_string).unwrap();
+
+    if let Value::Array(outputs) = json {
+        outputs
+            .iter()
+            .map(|output_json| Output {
+                name: String::from(output_json["name"].as_str().unwrap()),
+                make: String::from(output_json["make"].as_str().unwrap()),
+                model: String::from(output_json["model"].as_str().unwrap()),
+                serial: String::from(output_json["serial"].as_str().unwrap()),
+                output_config: OutputConfig {
+                    mode: get_mode(output_json),
+                    scale: String::from("1.0"),
+                    x: 0,
+                    y: 0,
+                    transform: String::from("normal"),
+                },
+            })
+            .collect()
+    } else {
+        panic!("outputs json was not an array");
+    }
+}
+
+/// Parse the mode from the output JSON into a string suitable for the mode param for sway-output.
+/// This will go into `OutputConfig.mode`.
+fn get_mode(output: &Value) -> String {
+    if let Value::Array(modes) = &output["modes"] {
+        if let Some(mode) = modes.first() {
+            let width = mode["width"].as_i64().unwrap().to_string();
+            let height = mode["height"].as_i64().unwrap().to_string();
+            let mut out: String = String::new();
+            out.push_str(&width);
+            out.push_str("x");
+            out.push_str(&height);
+            out
+        } else {
+            panic!("no modes")
+        }
+    } else {
+        panic!("modes not an array")
+    }
+}
+
+/// Apply the specified outputs. Enable all outputs in [outputs], disable others.
+pub fn apply_outputs(
+    all_outputs: &Vec<Output>,
+    outputs: &HashMap<&String, &OutputConfig>,
+) -> Result<(), String> {
+    // set enabled outputs first, then set disabled outputs.
+    // That way if some work before an error, you have at least one output enabled.
+
+    // for outputs to be enabled: map of output name to config
+    let mut enabled: HashMap<&String, &OutputConfig> = HashMap::new();
+    // for outputs to be disabled: output names
+    let mut disabled: Vec<&String> = Vec::new();
+
+    all_outputs.iter().for_each(|output| {
+        if let Some(output_config) = outputs.get(&output.name) {
+            enabled.insert(&output.name, &output_config);
+        } else {
+            disabled.push(&output.name);
+        }
+    });
+
+    if enabled.is_empty() {
+        return Err("No enabled outputs!".to_string());
+    }
+
+    let mut cmd = Command::new("swaymsg");
+    enabled.iter().for_each(|(output_name, output_config)| {
+        cmd.arg("output");
+        cmd.arg(&output_name);
+        cmd.arg("enable");
+        cmd.arg("mode");
+        cmd.arg(&output_config.mode);
+        cmd.arg("scale");
+        cmd.arg(&output_config.scale);
+        cmd.arg("pos");
+        cmd.arg(&output_config.x.to_string());
+        cmd.arg(&output_config.y.to_string());
+        cmd.arg("transform");
+        cmd.arg(&output_config.transform);
+        cmd.arg(",");
+    });
+
+    disabled.iter().for_each(|output_name| {
+        cmd.arg("output");
+        cmd.arg(&output_name);
+        cmd.arg("disable");
+        cmd.arg(",");
+    });
+
+    // print what we are about to do.
+    cmd.get_args()
+        .for_each(|arg| print!("{} ", arg.to_str().unwrap()));
+
+    cmd.output().expect("swaymsg output failed");
+
+    Ok(())
+}