2 files changed, 66 insertions, 0 deletions
diff --git a/niri-ipc/Cargo.toml b/niri-ipc/Cargo.toml
new file mode 100644
index 00000000..21207ac8
--- /dev/null
+++ b/niri-ipc/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "niri-ipc"
+version.workspace = true
+description.workspace = true
+authors.workspace = true
+license.workspace = true
+edition.workspace = true
+repository.workspace = true
+
+[dependencies]
+serde.workspace = true
diff --git a/niri-ipc/src/lib.rs b/niri-ipc/src/lib.rs
new file mode 100644
index 00000000..129e8f57
--- /dev/null
+++ b/niri-ipc/src/lib.rs
@@ -0,0 +1,55 @@
+//! Types for communicating with niri via IPC.
+#![warn(missing_docs)]
+
+use std::collections::HashMap;
+
+use serde::{Deserialize, Serialize};
+
+/// Name of the environment variable containing the niri IPC socket path.
+pub const SOCKET_PATH_ENV: &str = "NIRI_SOCKET";
+
+/// Request from client to niri.
+#[derive(Debug, Serialize, Deserialize)]
+pub enum Request {
+    /// Request information about connected outputs.
+    Outputs,
+}
+
+/// Response from niri to client.
+#[derive(Debug, Serialize, Deserialize)]
+pub enum Response {
+    /// Information about connected outputs.
+    ///
+    /// Map from connector name to output info.
+    Outputs(HashMap<String, Output>),
+}
+
+/// Connected output.
+#[derive(Debug, Serialize, Deserialize, Clone)]
+pub struct Output {
+    /// Name of the output.
+    pub name: String,
+    /// Textual description of the manufacturer.
+    pub make: String,
+    /// Textual description of the model.
+    pub model: String,
+    /// Physical width and height of the output in millimeters, if known.
+    pub physical_size: Option<(u32, u32)>,
+    /// Available modes for the output.
+    pub modes: Vec<Mode>,
+    /// Index of the current mode in [`Self::modes`].
+    ///
+    /// `None` if the output is disabled.
+    pub current_mode: Option<usize>,
+}
+
+/// Output mode.
+#[derive(Debug, Serialize, Deserialize, Clone, Copy)]
+pub struct Mode {
+    /// Width in physical pixels.
+    pub width: u16,
+    /// Height in physical pixels.
+    pub height: u16,
+    /// Refresh rate in millihertz.
+    pub refresh_rate: u32,
+}