feat: modem interface with AT command parsing

Cargo.toml

@@ -42,6 +42,8 @@ embassy-net = { version = "0.4.0", features = ["dhcpv4", "dhcpv4-hostname", "dns
 static_cell = { version = "2.1.0", features = ["nightly"] }
 embedded-io-async = { version = "0.6.1", features = ["alloc"] }
 embassy-sync = "0.6.0"
+embassy-futures = "0.1.1"
+atat = { version = "0.23.0", features = ["heapless", "log"] }
 
 [profile.dev]
 # Rust debug is too slow.
@@ -57,6 +59,10 @@ lto = 'fat'
 opt-level = 's'
 overflow-checks = false
 
+[build-dependencies]
+serde = { version = "1.0.210", features = ["derive"] }
+serde_yaml = "0.9.34"
+
 [package.metadata.espflash]
 partition_table = "partitions.csv"
 

build.rs

@@ -1,5 +1,25 @@
+#[derive(serde::Deserialize)]
+struct Config {
+    wifi_ssid: String,
+    wifi_password: String,
+}
+
+impl Config {
+    fn export_vars(&self) {
+        println!("cargo:rustc-env=WIFI_SSID={}", self.wifi_ssid);
+        println!("cargo:rustc-env=WIFI_PASSWORD={}", self.wifi_password);
+    }
+}
+
 fn main() {
     println!("cargo:rustc-link-arg-bins=-Tlinkall.x");
 
     println!("cargo:rustc-link-arg-bins=-Trom_functions.x");
+
+    println!("cargo:rerun-if-changed=config.yml");
+    let config = {
+        let config_string = std::fs::read_to_string("config.yml").expect("config.yml not found");
+        serde_yaml::from_str::<Config>(&config_string).expect("config.yml is not valid")
+    };
+    config.export_vars();
 }

flake.nix

@@ -59,7 +59,7 @@
           craneLib = crane.mkLib pkgs;
           craneToolchain = craneLib.overrideToolchain rustToolchain;
           src = craneLib.cleanCargoSource ./.;
-          commonArgs = rec {
+          commonArgs = {
             inherit src;
             cargoVendorDir = craneLib.vendorMultipleCargoDeps {
               cargoLockList = [
@@ -87,9 +87,17 @@
             buildInputs = with pkgs; [
               openssl
               pkg-config
-              esp-idf-esp32
+              esp-idf-esp32-with-clang
             ];
-            LD_LIBRARY_PATH = pkgs.lib.makeLibraryPath (buildInputs ++ [ rustToolchain ]);
+
+            # FIXME: this is a hack for cargo to find our linker
+            CARGO_TARGET_XTENSA_ESP32_NONE_ELF_LINKER =
+              let
+                deps = pkgs.esp-idf-esp32-with-clang.propagatedBuildInputs;
+                idfName = pkgs.esp-idf-esp32-with-clang.name;
+                targetPkg = builtins.head (builtins.filter (p: p.name == "esp-clang-${idfName}") deps);
+              in
+              "${targetPkg}/bin/xtensa-esp32-elf-ld";
           };
 
           cargoArtifacts = craneToolchain.buildDepsOnly commonArgs;
@@ -108,7 +116,7 @@
               buildInputs = [
                 openssl
                 pkg-config
-                esp-idf-esp32
+                esp-idf-esp32-with-clang
 
                 rustToolchain