INFRA - Initialise Core (#4)

Co-authored-by: David Beechey <david@dtbeechey.dev>

Cargo.toml

@@ -1,5 +1,6 @@
 [workspace]
 members = [
+    "lib/*",
     "config",
 ]
 resolver = "2"

lib/core/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "hyped_core"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+defmt = "0.3"
+heapless = { version = "0.8", default-features = false, features = ["serde"] }
+rust-mqtt = { version = "0.3.0", default-features = false, features = ["defmt"] }
+embedded-io-async = { version = "0.6.1" }
+rand_core = "0.6.3"
+serde = { version = "1.0", default-features = false, features = ["derive"] }
+embassy-net = { version = "0.4.0", default-features = false, features = ["defmt", "tcp", "proto-ipv4", "medium-ip"] }
+
+[features]
+std = []

lib/core/src/format_string.rs

@@ -0,0 +1,55 @@
+use core::cmp::min;
+use core::fmt;
+
+pub struct FormatString<'a> {
+    buffer: &'a mut [u8],
+    used: usize,
+}
+
+impl<'a> FormatString<'a> {
+    pub fn new(buffer: &'a mut [u8]) -> Self {
+        FormatString { buffer, used: 0 }
+    }
+
+    pub fn as_str(self) -> Option<&'a str> {
+        if self.used <= self.buffer.len() {
+            use core::str::from_utf8;
+            Some(from_utf8(&self.buffer[..self.used]).unwrap())
+        } else {
+            None
+        }
+    }
+}
+
+impl<'a> fmt::Write for FormatString<'a> {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        if self.used > self.buffer.len() {
+            return Err(fmt::Error);
+        }
+        let remaining_buf = &mut self.buffer[self.used..];
+        let raw_s = s.as_bytes();
+        let write_num = min(raw_s.len(), remaining_buf.len());
+        remaining_buf[..write_num].copy_from_slice(&raw_s[..write_num]);
+        self.used += raw_s.len();
+        if write_num < raw_s.len() {
+            Err(fmt::Error)
+        } else {
+            Ok(())
+        }
+    }
+}
+
+pub fn show<'a>(buffer: &'a mut [u8; 1024], args: fmt::Arguments) -> Result<&'a str, fmt::Error> {
+    let mut w = FormatString::new(buffer);
+    fmt::write(&mut w, args)?;
+    w.as_str().ok_or(fmt::Error)
+}
+
+#[macro_export]
+macro_rules! format {
+    ($buffer:expr, $($arg:tt)*) => {
+        {
+            show(&mut $buffer, format_args!($($arg)*))
+        }
+    };
+}

lib/core/src/lib.rs

@@ -0,0 +1,7 @@
+#![cfg_attr(not(feature = "std"), no_std)]
+
+pub mod format_string;
+pub mod log_types;
+pub mod mqtt;
+pub mod mqtt_topics;
+pub mod types;

lib/core/src/log_types.rs

@@ -0,0 +1,12 @@
+#[derive(PartialEq, PartialOrd)]
+pub enum LogLevel {
+    Debug = 0,
+    Info = 1,
+    Warn = 2,
+    Error = 3,
+}
+
+pub enum LogTarget {
+    Console,
+    Mqtt,
+}