refactor: increase channel sizes

Flake lock file updates:

• Updated input 'flake-parts':
    'github:hercules-ci/flake-parts/f7c1a2d347e4c52d5fb8d10cb4d94b5884e546fb?narHash=sha256-m1Yf0wZ8j1OHjTc2UwHwyQRSnNeSgLJOd7q5Y45hzi4%3D' (2026-05-13)
  → 'github:hercules-ci/flake-parts/024633cd702b10285db5cb19b40ad48d2399ba60?narHash=sha256-zTwuwezD0w3hpga6a6P8emidzAZFyWqlNeRBlpWOOl8%3D' (2026-10-01)
• Updated input 'flake-parts/nixpkgs-lib':
    'github:nix-community/nixpkgs.lib/f5901329dade4a6ea039af1433fb087bd9c1fe14?narHash=sha256-GOkGPcboWE9BmGCRMLX3worL4EMnsnG8MyKmXNeYuhQ%3D' (2026-04-26)
  → 'github:nix-community/nixpkgs.lib/f7cd230690d9fc982d06129f9189b101fddcfa3b?narHash=sha256-oujbxmVKDhci2E4EM3KyAbRUgp5/IsCoiA/LfEF7OOk%3D' (2026-09-27)
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/a799d3e3886da994fa307f817a6bc705ae538eeb?narHash=sha256-3av0pIjlOWQ6rDbNOmpUSvbNnJkGORQKKjb4LtCZsIY%3D' (2026-06-06)
  → 'github:nixos/nixpkgs/151fa4e8ddfdd8dd25d945ad94ed54a13de9f6e4?narHash=sha256-Miqqk/ammqnTUxaoCyvtwoPeLbI1ksFyLxi/CazZpWY%3D' (2026-10-06)
• Updated input 'project-templates':
    'git+https://git.krantz.one/reed/project-templates?ref=refs/heads/master&rev=0d1a37eef3e3954cc698b577edbc37eaa736b859' (2026-06-08)
  → 'git+https://git.krantz.one/reed/project-templates?ref=refs/heads/master&rev=00ab3b0148e915f22ef6815a9fe24de5d8dde295' (2026-10-08)
• Updated input 'project-templates/crane':
    'github:ipetkov/crane/5e0fb2f64edff2822249f21293b8304dedaaf676?narHash=sha256-bEg5xoAxAwsyfnGhkEX7RJViTIBIYPd8ISg4O1c0HFc%3D' (2026-04-28)
  → 'github:ipetkov/crane/47b6b27ed9a3a9181415e4367d0c30ab2a0e0250?narHash=sha256-THGtz65UGJU%2BsonZidRboyCMk%2B9DclpMF7pwL4uDV4M%3D' (2026-10-02)
• Updated input 'project-templates/rust-overlay':
    'github:oxalica/rust-overlay/21632e942d89bf1cce4e5a63d7e58a215a0cbfcc?narHash=sha256-FVCr2Ij/jKf59a4LW481eeOF6rJRreOBrVgW/aUBTrw%3D' (2026-05-31)
  → 'github:oxalica/rust-overlay/b962e5d0c8cd97196c6a882d659fe451b52ad989?narHash=sha256-iwqAmHTX1IgzTumJR3JayNAQAo5xEmmOuGzB6b2pT/Q%3D' (2026-10-06)
• Updated input 'project-templates/treefmt-nix':
    'github:numtide/treefmt-nix/790751ff7fd3801feeaf96d7dc416a8d581265ba?narHash=sha256-pc20NRoMdiar8oPQceQT47UUZMBTiMdUuWrYu2obUP0%3D' (2026-04-08)
  → 'github:numtide/treefmt-nix/03d8ee1bcbc8f9638907bb79edb9673151d0e22b?narHash=sha256-vuzVwvjeucSnwKwMBpyP8r5IzdrMKCHEdwTrRFwUN7I%3D' (2026-10-05)

Cargo.toml

@@ -34,7 +34,6 @@ esp-println = { version = "0.17.0", features = ["defmt-espflash", "esp32c6"] }
 embassy-sync = { version = "0.8.0", features = ["defmt"] }
 embassy-futures = { version = "0.1.2", features = ["defmt"] }
 embassy-embedded-hal = { version = "0.6.0", features = ["defmt", "time"] }
-embedded-rpc = "0.2.0"
 
 critical-section = "1.2.0"
 static_cell = { version = "2.1.1", features = ["nightly"] }
@@ -64,9 +63,15 @@ picoserve = { version = "0.19", features = ["defmt", "embassy", "json"] }
 
 sequential-storage = "8.0"
 esp-storage = { version = "0.9", features = ["defmt", "esp32c6"] }
-postcard = { version = "1.1", default-features = false }
+postcard = { version = "1.1", default-features = false, features = [
+  "defmt",
+  "heapless",
+] }
 serde = { version = "1.0", default-features = false, features = ["derive"] }
 int-enum = "1.2.0"
+heapless = { version = "0.9.3", features = ["defmt", "serde"] }
+thiserror = { version = "2.0.20", default-features = false }
+oneshot = { version = "0.2.1", features = ["async"] }
 
 
 # For fine tuning these settings, please refer to https://doc.rust-lang.org/cargo/reference/profiles.html

flake.lock

@@ -95,11 +95,11 @@
     },
     "crane": {
       "locked": {
-        "lastModified": 1777335812,
-        "narHash": "sha256-bEg5xoAxAwsyfnGhkEX7RJViTIBIYPd8ISg4O1c0HFc=",
+        "lastModified": 1790899423,
+        "narHash": "sha256-THGtz65UGJU+sonZidRboyCMk+9DclpMF7pwL4uDV4M=",
         "owner": "ipetkov",
         "repo": "crane",
-        "rev": "5e0fb2f64edff2822249f21293b8304dedaaf676",
+        "rev": "47b6b27ed9a3a9181415e4367d0c30ab2a0e0250",
         "type": "github"
       },
       "original": {
@@ -113,11 +113,11 @@
         "nixpkgs-lib": "nixpkgs-lib"
       },
       "locked": {
-        "lastModified": 1778716662,
-        "narHash": "sha256-m1Yf0wZ8j1OHjTc2UwHwyQRSnNeSgLJOd7q5Y45hzi4=",
+        "lastModified": 1790898470,
+        "narHash": "sha256-zTwuwezD0w3hpga6a6P8emidzAZFyWqlNeRBlpWOOl8=",
         "owner": "hercules-ci",
         "repo": "flake-parts",
-        "rev": "f7c1a2d347e4c52d5fb8d10cb4d94b5884e546fb",
+        "rev": "024633cd702b10285db5cb19b40ad48d2399ba60",
         "type": "github"
       },
       "original": {
@@ -146,11 +146,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1780749050,
-        "narHash": "sha256-3av0pIjlOWQ6rDbNOmpUSvbNnJkGORQKKjb4LtCZsIY=",
+        "lastModified": 1791260994,
+        "narHash": "sha256-Miqqk/ammqnTUxaoCyvtwoPeLbI1ksFyLxi/CazZpWY=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "a799d3e3886da994fa307f817a6bc705ae538eeb",
+        "rev": "151fa4e8ddfdd8dd25d945ad94ed54a13de9f6e4",
         "type": "github"
       },
       "original": {
@@ -162,11 +162,11 @@
     },
     "nixpkgs-lib": {
       "locked": {
-        "lastModified": 1777168982,
-        "narHash": "sha256-GOkGPcboWE9BmGCRMLX3worL4EMnsnG8MyKmXNeYuhQ=",
+        "lastModified": 1790477367,
+        "narHash": "sha256-oujbxmVKDhci2E4EM3KyAbRUgp5/IsCoiA/LfEF7OOk=",
         "owner": "nix-community",
         "repo": "nixpkgs.lib",
-        "rev": "f5901329dade4a6ea039af1433fb087bd9c1fe14",
+        "rev": "f7cd230690d9fc982d06129f9189b101fddcfa3b",
         "type": "github"
       },
       "original": {
@@ -238,11 +238,11 @@
         "treefmt-nix": "treefmt-nix"
       },
       "locked": {
-        "lastModified": 1780887496,
-        "narHash": "sha256-4mDOPU6Ey3SMsUsUeeNLkXC9uSdn0vpyzJIumw01HV8=",
+        "lastModified": 1791419199,
+        "narHash": "sha256-eQx167Svp11qqWgwFrvV+tELtWZ+Wu2+zgKsAl8fx0M=",
         "ref": "refs/heads/master",
-        "rev": "0d1a37eef3e3954cc698b577edbc37eaa736b859",
-        "revCount": 45,
+        "rev": "00ab3b0148e915f22ef6815a9fe24de5d8dde295",
+        "revCount": 51,
         "type": "git",
         "url": "https://git.krantz.one/reed/project-templates"
       },
@@ -298,11 +298,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1780197589,
-        "narHash": "sha256-FVCr2Ij/jKf59a4LW481eeOF6rJRreOBrVgW/aUBTrw=",
+        "lastModified": 1791276535,
+        "narHash": "sha256-iwqAmHTX1IgzTumJR3JayNAQAo5xEmmOuGzB6b2pT/Q=",
         "owner": "oxalica",
         "repo": "rust-overlay",
-        "rev": "21632e942d89bf1cce4e5a63d7e58a215a0cbfcc",
+        "rev": "b962e5d0c8cd97196c6a882d659fe451b52ad989",
         "type": "github"
       },
       "original": {
@@ -334,11 +334,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1775636079,
-        "narHash": "sha256-pc20NRoMdiar8oPQceQT47UUZMBTiMdUuWrYu2obUP0=",
+        "lastModified": 1791203292,
+        "narHash": "sha256-vuzVwvjeucSnwKwMBpyP8r5IzdrMKCHEdwTrRFwUN7I=",
         "owner": "numtide",
         "repo": "treefmt-nix",
-        "rev": "790751ff7fd3801feeaf96d7dc416a8d581265ba",
+        "rev": "03d8ee1bcbc8f9638907bb79edb9673151d0e22b",
         "type": "github"
       },
       "original": {

src/bin/main.rs

@@ -7,7 +7,7 @@
 )]
 #![deny(clippy::large_stack_frames)]
 
-use cover_theif::wifi::start_wifi;
+use cover_theif::{clock::start_ntp_sync, http_api::start_http_api, wifi::start_wifi};
 use defmt::info;
 use embassy_executor::Spawner;
 use embassy_time::{Duration, Timer};
@@ -16,11 +16,6 @@ use esp_hal::clock::CpuClock;
 use esp_hal::timer::timg::TimerGroup;
 use esp_println as _;
 
-use cover_theif::{
-    clock,
-    http_api::{HttpApiProps, HttpApiService},
-};
-
 extern crate alloc;
 
 // This creates a default app-descriptor required by the esp-idf bootloader.
@@ -50,16 +45,8 @@ async fn main(spawner: Spawner) -> ! {
 
     let net_stack = start_wifi(spawner, peripherals.WIFI);
 
-    spawner.spawn(clock::ntp_upkeep_service(net_stack).unwrap());
-
-    spawner.spawn(
-        http_api_serve_task(HttpApiService::new(
-            net_stack,
-            Default::default(),
-            Default::default(),
-        ))
-        .unwrap(),
-    );
+    start_ntp_sync(spawner, net_stack);
+    start_http_api(spawner, net_stack);
 
     loop {
         info!("Hello world");
@@ -68,8 +55,3 @@ async fn main(spawner: Spawner) -> ! {
 
     // for inspiration have a look at the examples at https://github.com/esp-rs/esp-hal/tree/esp-hal-v1.1.0/examples
 }
-
-#[embassy_executor::task]
-async fn http_api_serve_task(mut service: HttpApiService<'static, HttpApiProps>) {
-    service.run().await;
-}

src/clock.rs

@@ -1,5 +1,9 @@
 use core::net::SocketAddr;
-use embassy_net::udp::{PacketMetadata, UdpSocket};
+use embassy_executor::Spawner;
+use embassy_net::{
+    Stack,
+    udp::{PacketMetadata, UdpSocket},
+};
 use embassy_time::{Duration, Timer};
 use portable_atomic::{AtomicU64, Ordering};
 use sntpc::{NtpContext, get_time};
@@ -9,43 +13,29 @@ use sntpc_time_embassy::EmbassyTimestampGenerator;
 // NTP server (pool.ntp.org is the usual choice)
 const NTP_SERVER: &str = "pool.ntp.org";
 const NTP_PORT: u16 = 123;
+// Unix epoch is 1900-01-01 + 70 years = 2_208_988_800 seconds.
+const NTP_UNIX_OFFSET: u64 = 2_208_988_800;
 
 static NTP_BOOT_OFFSET: AtomicU64 = AtomicU64::new(0);
 
-pub async fn fetch_ntp_time(stack: embassy_net::Stack<'static>) -> Result<u64, &'static str> {
-    // Resolve the NTP server hostname
-    let server_addr = stack
-        .dns_query(NTP_SERVER, embassy_net::dns::DnsQueryType::A)
-        .await
-        .map_err(|_| "DNS resolution failed")?
-        .first()
-        .copied()
-        .ok_or("No DNS result")?;
+#[allow(
+    clippy::large_stack_frames,
+    reason = "it's not unusual to allocate larger objects in service's start functions"
+)]
+pub fn start_ntp_sync(spawner: Spawner, net_stack: Stack<'static>) {
+    let service = crate::mk_static!(
+        NtpClient,
+        NtpClient {
+            net_stack,
 
-    let socket_addr = SocketAddr::new(server_addr.into(), NTP_PORT);
+            rx_meta: [PacketMetadata::EMPTY; 16],
+            rx_buf: [0u8; 48],
+            tx_meta: [PacketMetadata::EMPTY; 16],
+            tx_buf: [0u8; 48],
+        }
+    );
 
-    // Allocate UDP buffers (can be small — SNTP packets are tiny)
-    let mut rx_meta = [PacketMetadata::EMPTY; 16];
-    let mut rx_buf = [0u8; 48];
-    let mut tx_meta = [PacketMetadata::EMPTY; 16];
-    let mut tx_buf = [0u8; 48];
-
-    let mut socket = UdpSocket::new(stack, &mut rx_meta, &mut rx_buf, &mut tx_meta, &mut tx_buf);
-    socket.bind(0).map_err(|_| "bind failed")?;
-
-    let wrapped = UdpSocketWrapper::from(socket);
-    let ctx = NtpContext::new(EmbassyTimestampGenerator::default());
-
-    let result = get_time(socket_addr, &wrapped, ctx)
-        .await
-        .map_err(|_| "SNTP request failed")?;
-
-    // result.sec is the NTP timestamp in seconds since 1900-01-01.
-    // Unix epoch is 1900-01-01 + 70 years = 2_208_988_800 seconds.
-    const NTP_UNIX_OFFSET: u64 = 2_208_988_800;
-    let unix_secs = result.sec().saturating_sub(NTP_UNIX_OFFSET);
-
-    Ok(unix_secs)
+    spawner.spawn(handler(service).unwrap());
 }
 
 pub fn now() -> embassy_time::Instant {
@@ -53,9 +43,19 @@ pub fn now() -> embassy_time::Instant {
 }
 
 #[embassy_executor::task]
-pub async fn ntp_upkeep_service(stack: embassy_net::Stack<'static>) {
+async fn handler(service: &'static mut NtpClient) {
+    let address = loop {
+        match service.fetch_ntp_address(NTP_SERVER, NTP_PORT).await {
+            Ok(addr) => break addr,
+            Err(err) => {
+                defmt::error!("Failed to get the NTP server's address: {}", err);
+                Timer::after(Duration::from_secs(10)).await
+            }
+        }
+    };
+
     loop {
-        match fetch_ntp_time(stack).await {
+        match service.fetch_ntp_time(address).await {
             Ok(unix_secs) => {
                 NTP_BOOT_OFFSET.store(
                     unix_secs - embassy_time::Instant::now().as_secs(),
@@ -70,3 +70,51 @@ pub async fn ntp_upkeep_service(stack: embassy_net::Stack<'static>) {
         }
     }
 }
+
+struct NtpClient {
+    net_stack: Stack<'static>,
+
+    rx_meta: [PacketMetadata; 16],
+    rx_buf: [u8; 48],
+    tx_meta: [PacketMetadata; 16],
+    tx_buf: [u8; 48],
+}
+
+impl NtpClient {
+    async fn fetch_ntp_address(&self, server: &str, port: u16) -> Result<SocketAddr, &'static str> {
+        // Resolve the NTP server hostname
+        let server_addr = self
+            .net_stack
+            .dns_query(server, embassy_net::dns::DnsQueryType::A)
+            .await
+            .map_err(|_| "DNS resolution failed")?
+            .first()
+            .copied()
+            .ok_or("No DNS result")?;
+
+        Ok(SocketAddr::new(server_addr.into(), port))
+    }
+
+    async fn fetch_ntp_time(&mut self, address: SocketAddr) -> Result<u64, &'static str> {
+        let mut socket = UdpSocket::new(
+            self.net_stack,
+            &mut self.rx_meta,
+            &mut self.rx_buf,
+            &mut self.tx_meta,
+            &mut self.tx_buf,
+        );
+        socket.bind(0).map_err(|_| "bind failed")?;
+
+        let wrapped = UdpSocketWrapper::from(socket);
+        let ctx = NtpContext::new(EmbassyTimestampGenerator::default());
+
+        let result = get_time(address, &wrapped, ctx)
+            .await
+            .map_err(|_| "SNTP request failed")?;
+
+        // result.sec is the NTP timestamp in seconds since 1900-01-01.
+        let unix_secs = result.sec().saturating_sub(NTP_UNIX_OFFSET);
+
+        Ok(unix_secs)
+    }
+}

src/config.rs

@@ -1,25 +1,20 @@
+use defmt::error;
 use embassy_embedded_hal::adapter::BlockingAsync;
 use embassy_executor::Spawner;
-use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
-use embedded_rpc::RpcService;
+use embassy_sync::{blocking_mutex::raw::CriticalSectionRawMutex, channel::Channel};
 use esp_hal::peripherals::FLASH;
+use esp_radio::wifi::sta::StationConfig;
 use esp_storage::FlashStorage;
+use heapless::String;
 use int_enum::IntEnum;
+use oneshot::Sender;
+use postcard::to_slice;
 use sequential_storage::{
     cache::{Cache, Uncached},
-    map::{Key, MapConfig, MapStorage, SerializationError},
+    map::{Key, MapConfig, MapStorage},
 };
-
-pub enum ConfigCommand {
-    SetStationCreds(),
-}
-
-impl ConfigCommand {
-    pub async fn set_station_creds() {}
-}
-
-pub static CONFIG_SERVICE: RpcService<CriticalSectionRawMutex, ConfigCommand, ()> =
-    RpcService::new();
+use serde::{Deserialize, Serialize};
+use thiserror::Error;
 
 pub async fn start_config(spawner: Spawner, flash: FLASH<'static>) {
     let storage = MapStorage::<ConfigKey, _, _>::new(
@@ -28,26 +23,72 @@ pub async fn start_config(spawner: Spawner, flash: FLASH<'static>) {
         Cache::new_uncached(),
     );
 
-    spawner.spawn(config_handler(storage).unwrap());
+    spawner.spawn(handler(storage).unwrap());
 }
 
+pub async fn set_wifi_creds(value: WifiCredentials) -> Result<(), ConfigError> {
+    let (send, recv) = oneshot::channel();
+    CONFIG_CHANNEL
+        .send(ConfigOperationMessage::SetWifiCreds(value, send))
+        .await;
+    recv.await?
+}
+
+static CONFIG_CHANNEL: Channel<CriticalSectionRawMutex, ConfigOperationMessage, 5> = Channel::new();
+
+enum ConfigOperationMessage {
+    SetWifiCreds(WifiCredentials, Sender<Result<(), ConfigError>>),
+}
+
+#[derive(Debug, Deserialize, Serialize)]
+pub struct WifiCredentials {
+    pub ssid: String<32>,
+    pub password: String<32>,
+}
+
+impl From<WifiCredentials> for StationConfig {
+    fn from(value: WifiCredentials) -> Self {
+        Self::default()
+            .with_ssid(value.ssid.as_str())
+            .with_password(value.password.as_str().into())
+    }
+}
+
+// TODO: refactor this when try blocks are implemented
 #[embassy_executor::task]
-async fn config_handler(mut storage: MapStorage<ConfigKey, BlockingAsync<FlashStorage<'static>>, Cache<Uncached, Uncached, Uncached, ConfigKey>>) {
+async fn handler(
+    mut storage: MapStorage<
+        ConfigKey,
+        BlockingAsync<FlashStorage<'static>>,
+        Cache<Uncached, Uncached, Uncached, ConfigKey>,
+    >,
+) -> ! {
     let mut data_buffer = [0u8; 256];
 
     loop {
-        let (req, served) = CONFIG_SERVICE.serve().await;
+        let operation = CONFIG_CHANNEL.receive().await;
 
-        match req {
-            ConfigCommand::SetStationCreds() => {
-                todo!()
-                // if storage
-                //     .store_item(&mut data_buffer, &ConfigKey::Wifi, )
-                //     .await
-                //     .is_ok()
-                // {
-                //     served.respond(());
-                // }
+        match operation {
+            ConfigOperationMessage::SetWifiCreds(value, resp) => {
+                let mut f = async || {
+                    let mut buf = [0u8; 256];
+                    to_slice(&value, &mut buf)?;
+
+                    storage
+                        .store_item(&mut data_buffer, &ConfigKey::Wifi, &buf)
+                        .await?;
+
+                    // TODO: send the change to the wifi service
+                    // WIFI_SERVICE
+                    //     .call(|s| s.set_station_config(esp_radio::wifi::Config::Station(value.into())))
+                    //     .await;
+
+                    Ok(())
+                };
+                if resp.send(f().await).is_err() {
+                    // TODO: find a way to not hard-code symbols in a string
+                    error!("ConfigOperationMessage::SetWifiCreds failed to respond")
+                };
             }
         }
     }
@@ -60,18 +101,55 @@ enum ConfigKey {
 }
 
 impl Key for ConfigKey {
-    fn get_len(_: &[u8]) -> Result<usize, SerializationError> {
+    fn get_len(_: &[u8]) -> Result<usize, sequential_storage::map::SerializationError> {
         Ok(1)
     }
 
-    fn serialize_into(&self, buffer: &mut [u8]) -> Result<usize, SerializationError> {
-        let val = buffer.get_mut(0).ok_or(SerializationError::BufferTooSmall)?;
-        *val = self.clone().into();
+    fn serialize_into(
+        &self,
+        buffer: &mut [u8],
+    ) -> Result<usize, sequential_storage::map::SerializationError> {
+        let val = buffer
+            .get_mut(0)
+            .ok_or(sequential_storage::map::SerializationError::BufferTooSmall)?;
+        *val = (*self).into();
         Ok(1)
     }
 
-    fn deserialize_from(buffer: &[u8]) -> Result<(Self, usize), SerializationError> {
-        let val = *buffer.get(0).ok_or(SerializationError::BufferTooSmall)?;
-        Ok((val.try_into().map_err(|_| {SerializationError::InvalidData})?, 1))
+    fn deserialize_from(
+        buffer: &[u8],
+    ) -> Result<(Self, usize), sequential_storage::map::SerializationError> {
+        let val = *buffer
+            .first()
+            .ok_or(sequential_storage::map::SerializationError::BufferTooSmall)?;
+        Ok((
+            val.try_into()
+                .map_err(|_| sequential_storage::map::SerializationError::InvalidData)?,
+            1,
+        ))
+    }
+}
+
+#[derive(Error, Debug)]
+pub enum ConfigError {
+    #[error("Error serializing data: {0}")]
+    SerializationError(#[from] postcard::Error),
+
+    #[error("Error storing data on the flash: {0:?}")]
+    FlashError(sequential_storage::Error<esp_storage::FlashStorageError>),
+
+    #[error("Error receiving response: {0}")]
+    RecvError(oneshot::RecvError),
+}
+
+impl From<sequential_storage::Error<esp_storage::FlashStorageError>> for ConfigError {
+    fn from(v: sequential_storage::Error<esp_storage::FlashStorageError>) -> Self {
+        Self::FlashError(v)
+    }
+}
+
+impl From<oneshot::RecvError> for ConfigError {
+    fn from(v: oneshot::RecvError) -> Self {
+        Self::RecvError(v)
     }
 }

src/http_api.rs

@@ -1,3 +1,4 @@
+use embassy_executor::Spawner;
 use embassy_net::Stack;
 use picoserve::routing::get;
 use picoserve::{AppBuilder, AppRouter, Config};
@@ -13,6 +14,33 @@ impl AppBuilder for HttpApiProps {
     }
 }
 
+#[allow(
+    clippy::large_stack_frames,
+    reason = "it's not unusual to allocate larger objects in service's start functions"
+)]
+pub fn start_http_api(spawner: Spawner, net_stack: Stack<'static>) {
+    let service = crate::mk_static!(
+        HttpApiApp<'static, HttpApiProps>,
+        HttpApiApp {
+            config: Default::default(),
+
+            net_stack,
+            app: HttpApiProps.build_app(),
+
+            tcp_rx_buffer: [0; 1024],
+            tcp_tx_buffer: [0; 1024],
+            http_buffer: [0; 2048],
+        }
+    );
+
+    spawner.spawn(handler(service).unwrap());
+}
+
+#[embassy_executor::task]
+async fn handler(service: &'static mut HttpApiApp<'static, HttpApiProps>) {
+    service.run().await;
+}
+
 pub struct HttpApiConfig {
     pub port: u16,
     pub web_serve_config: Config,
@@ -27,7 +55,7 @@ impl Default for HttpApiConfig {
     }
 }
 
-pub struct HttpApiService<'a, AB: AppBuilder> {
+pub struct HttpApiApp<'a, AB: AppBuilder> {
     config: HttpApiConfig,
 
     net_stack: Stack<'a>,
@@ -38,20 +66,7 @@ pub struct HttpApiService<'a, AB: AppBuilder> {
     http_buffer: [u8; 2048],
 }
 
-impl<'a, AB: AppBuilder> HttpApiService<'a, AB> {
-    pub fn new(net_stack: Stack<'a>, config: HttpApiConfig, app: AB) -> Self {
-        Self {
-            config: config,
-
-            net_stack: net_stack,
-            app: app.build_app(),
-
-            tcp_rx_buffer: [0; 1024],
-            tcp_tx_buffer: [0; 1024],
-            http_buffer: [0; 2048],
-        }
-    }
-
+impl<'a, AB: AppBuilder> HttpApiApp<'a, AB> {
     pub async fn run(&mut self) {
         picoserve::Server::new(
             &self.app,

src/lib.rs

@@ -7,6 +7,8 @@
 #![deny(clippy::large_stack_frames)]
 #![feature(impl_trait_in_assoc_type)]
 
+extern crate alloc;
+
 pub mod http_api;
 
 pub mod clock;

src/wifi.rs

@@ -1,31 +1,21 @@
+use alloc::boxed::Box;
 use defmt::{error, info};
 use embassy_executor::Spawner;
 use embassy_futures::select::{Either, select};
 use embassy_net::{Runner, Stack};
 use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
+use embassy_sync::channel::Channel;
+use embassy_sync::signal::Signal;
 use embassy_time::{Duration, Timer};
-use embedded_rpc::{RequestDroppedError, RpcService};
 use esp_hal::peripherals::WIFI;
 use esp_radio::wifi::sta::StationConfig;
 use esp_radio::wifi::{ControllerConfig, Interface, WifiController};
+use oneshot::{RecvError, Sender};
 
-pub enum WifiCommand {
-    SetStationConfig(esp_radio::wifi::Config),
-    SetDhcpConfig(embassy_net::DhcpConfig),
-}
-
-impl WifiCommand {
-    pub async fn set_station_config(
-        config: esp_radio::wifi::Config,
-    ) -> Result<(), RequestDroppedError> {
-        WIFI_SERVICE
-            .request(WifiCommand::SetStationConfig(config))
-            .await
-    }
-}
-
-pub static WIFI_SERVICE: RpcService<CriticalSectionRawMutex, WifiCommand, ()> = RpcService::new();
-
+#[allow(
+    clippy::large_stack_frames,
+    reason = "it's not unusual to allocate larger objects in service's start functions"
+)]
 pub fn start_wifi(spawner: Spawner, wifi: WIFI<'static>) -> Stack<'static> {
     let wifi_config = esp_radio::wifi::Config::Station(StationConfig::default());
 
@@ -52,40 +42,64 @@ pub fn start_wifi(spawner: Spawner, wifi: WIFI<'static>) -> Stack<'static> {
         seed,
     );
 
-    spawner.spawn(net_task(net_runner).unwrap());
-    spawner.spawn(wifi_handler(wifi_controller).unwrap());
-    spawner.spawn(ip_logger(net_stack).unwrap());
+    spawner.spawn(net_handler(net_runner).unwrap());
+    spawner.spawn(connection_handler(wifi_controller).unwrap());
     spawner.spawn(handler(net_stack).unwrap());
+    spawner.spawn(ip_logger(net_stack).unwrap());
 
     net_stack
 }
 
+pub async fn set_station_config(config: Box<esp_radio::wifi::Config>) -> Result<(), RecvError> {
+    let (send, recv) = oneshot::channel();
+    WIFI_CHANNEL
+        .send(WifiOperationMessage::SetStationConfig(config, send))
+        .await;
+    recv.await
+}
+
+pub async fn set_dhcp_config(config: Box<embassy_net::DhcpConfig>) -> Result<(), RecvError> {
+    let (send, recv) = oneshot::channel();
+    WIFI_CHANNEL
+        .send(WifiOperationMessage::SetDhcpConfig(config, send))
+        .await;
+    recv.await
+}
+
+static WIFI_CHANNEL: Channel<CriticalSectionRawMutex, WifiOperationMessage, 5> = Channel::new();
+
+enum WifiOperationMessage {
+    SetStationConfig(Box<esp_radio::wifi::Config>, Sender<()>),
+    SetDhcpConfig(Box<embassy_net::DhcpConfig>, Sender<()>),
+}
+
 #[embassy_executor::task]
-async fn handler(net_stack: Stack<'static>) {
+async fn handler(net_stack: Stack<'static>) -> ! {
     loop {
-        let (req, served) = WIFI_SERVICE.serve().await;
-
-        match req {
-            WifiCommand::SetStationConfig(config) => {
-                if WIFI_HANDLER_RPC.request(config).await.is_err() {
-                    continue;
+        match WIFI_CHANNEL.receive().await {
+            WifiOperationMessage::SetStationConfig(config, resp) => {
+                WIFI_HANDLER_RPC.signal(*config);
+                if resp.send(()).is_err() {
+                    // TODO: find a way to not hard-code symbols in a string
+                    error!("WifiOperationMessage::SetStationConfig failed to respond")
+                };
+            }
+            WifiOperationMessage::SetDhcpConfig(config, resp) => {
+                net_stack.set_config_v4(embassy_net::ConfigV4::Dhcp(*config));
+                if resp.send(()).is_err() {
+                    // TODO: find a way to not hard-code symbols in a string
+                    error!("WifiOperationMessage::SetDhcpConfig failed to respond")
+                };
             }
         }
-            WifiCommand::SetDhcpConfig(dhcp_config) => {
-                net_stack.set_config_v4(embassy_net::ConfigV4::Dhcp(dhcp_config));
     }
 }
 
-        served.respond(());
-    }
-}
-
-static WIFI_HANDLER_RPC: RpcService<CriticalSectionRawMutex, esp_radio::wifi::Config, ()> =
-    RpcService::new();
+static WIFI_HANDLER_RPC: Signal<CriticalSectionRawMutex, esp_radio::wifi::Config> = Signal::new();
 
 #[embassy_executor::task]
-async fn wifi_handler(mut controller: WifiController<'static>) {
-    let connection = async |controller: &mut WifiController<'static>| {
+async fn connection_handler(mut controller: WifiController<'static>) -> ! {
+    async fn connection(controller: &mut WifiController<'static>) {
         info!("Connecting to WiFi...");
 
         match controller.connect_async().await {
@@ -100,21 +114,20 @@ async fn wifi_handler(mut controller: WifiController<'static>) {
                 error!("Failed to connect to wifi: {:?}", e);
             }
         }
-    };
+    }
 
     loop {
-        if let Either::First((req, served)) =
-            select(WIFI_HANDLER_RPC.serve(), connection(&mut controller)).await
+        if let Either::First(req) =
+            select(WIFI_HANDLER_RPC.wait(), connection(&mut controller)).await
+            && let Some(err) = controller.set_config(&req).err()
         {
-            if controller.set_config(&req).is_ok() {
-                served.respond(());
-            }
+            error!("Wifi controller failed to set a new config: {:?}", err)
         }
     }
 }
 
 #[embassy_executor::task]
-async fn ip_logger(net_stack: Stack<'static>) {
+async fn ip_logger(net_stack: Stack<'static>) -> ! {
     loop {
         info!("Getting IP address...");
         net_stack.wait_config_up().await;
@@ -137,6 +150,6 @@ async fn ip_logger(net_stack: Stack<'static>) {
 }
 
 #[embassy_executor::task]
-async fn net_task(mut runner: Runner<'static, Interface<'static>>) {
+async fn net_handler(mut runner: Runner<'static, Interface<'static>>) -> ! {
     runner.run().await
 }