Merge pull request #24 from rursprung/add-support-for-alloc

add support for `alloc::vec::Vec`

Author: rursprung

.github/workflows/CI.yml

@@ -11,7 +11,7 @@ jobs:
       fail-fast: false
       matrix:
         rust: [1.62.0, stable]
-        features: ['', '--all-features']
+        features: ['use_alloc', 'use_alloc,defmt', 'use_heapless', 'use_heapless,defmt']
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
@@ -21,15 +21,15 @@ jobs:
           toolchain: ${{ matrix.rust }}
           components: rustfmt clippy
       - name: build
-        run: cargo build ${{ matrix.features }}
+        run: cargo build --features ${{ matrix.features }}
       - name: check
-        run: cargo check ${{ matrix.features }}
+        run: cargo check --features ${{ matrix.features }}
       - name: test
-        run: cargo test ${{ matrix.features }}
+        run: cargo test --features ${{ matrix.features }}
       - name: check formatting
         run: cargo fmt --all -- --check
       - name: clippy
-        run: cargo clippy ${{ matrix.features }}
+        run: cargo clippy --features ${{ matrix.features }}
       - name: audit
         run: cargo audit
 

CHANGELOG.md

@@ -6,9 +6,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 <!-- next-header -->
 ## [Unreleased] - ReleaseDate
+### Added
+* Add support for using [`alloc::vec::Vec`](https://doc.rust-lang.org/alloc/vec/struct.Vec.html)
 ### Changed
 * Due to dependency updates the MSRV has been updated from 1.60 to 1.62. This should only be relevant if you use the `defmt` feature, but we now only test with 1.62 and not older releases, so it's not guaranteed to work otherwise.
 * Update to `heapless:0.8.0`
+### Breaking Changes
+* You must now select either the feature `use_alloc` or `use_heapless` for the crate to compile. Select `use_heapless`
+  to keep the API from the previous release of this crate.
 
 ## [0.1.1] - 2023-01-07
 ### Changed

Cargo.toml

@@ -12,15 +12,18 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 defmt = { version = "0.3", optional = true }
-heapless = { version = "0.8" }
+heapless = { version = "0.8", optional = true }
 
 rgb = { version = "0.8", optional = true }
 serde = { version = "1.0", features = ["derive"], optional = true }
 
 [features]
 default = ["accelerometer_event", "button_event", "color_event", "gyro_event", "location_event", "magnetometer_event", "quaternion_event"]
 
-defmt = ["dep:defmt", "heapless/defmt-03"]
+use_heapless = ["dep:heapless"]
+use_alloc = []
+
+defmt = ["dep:defmt", "heapless?/defmt-03"]
 
 accelerometer_event = []
 button_event = []

README.md

@@ -9,7 +9,13 @@ which is e.g. used by the [Adafruit Bluefruit LE UART Friend](https://learn.adaf
 
 Note that this work is not affiliated with Adafruit.
 
-## Optional features
+## Mandatory Features
+This crate is `no_std` and you can choose whether you want to use
+[`heapless::Vec`](https://docs.rs/heapless/0.8.0/heapless/struct.Vec.html) by selecting the feature `use_heapless` or
+[`alloc::vec::Vec`](https://doc.rust-lang.org/alloc/vec/struct.Vec.html) by selecting the feature `use_alloc`.
+If you select neither or both you'll get a compile error.
+
+## Optional Features
 * `defmt`: you can enable the [`defmt`](https://defmt.ferrous-systems.com/) feature to get a `defmt::Format` implementation for all structs & enums and a `defmt::debug!` call for each command being parsed.
 * `rgb`: if enabled, `From<ColorEvent> for RGB8` is implemented to support the [RGB crate](https://crates.io/crates/rgb).
 * `serde`: if enabled, all events implement the [serde](https://serde.rs/) `#[derive(Serialize, Deserialize)]`.

examples/stm32f4-event-printer/Cargo.toml

@@ -17,7 +17,7 @@ defmt = "0.3.5"
 defmt-rtt = "0.4"
 
 # use `adafruit-bluefruit-protocol = "0.1"` in reality; path used here to ensure that the example always compiles against the latest master
-adafruit-bluefruit-protocol = { path = "../..", features = ["defmt"] }
+adafruit-bluefruit-protocol = { path = "../..", features = ["defmt", "use_heapless"] }
 
 [profile.release]
 codegen-units = 1

src/lib.rs

@@ -29,6 +29,12 @@
 )))]
 compile_error!("at least one event type must be selected in the features!");
 
+#[cfg(not(any(feature = "use_alloc", feature = "use_heapless")))]
+compile_error!("you must choose either 'use_alloc' or 'use_heapless' as a feature!");
+
+#[cfg(all(feature = "use_alloc", feature = "use_heapless"))]
+compile_error!("you must choose either 'use_alloc' or 'use_heapless' as a feature but not both!");
+
 #[cfg(feature = "accelerometer_event")]
 pub mod accelerometer_event;
 #[cfg(feature = "button_event")]
@@ -53,7 +59,13 @@ use color_event::ColorEvent;
 use core::cmp::min;
 #[cfg(feature = "gyro_event")]
 use gyro_event::GyroEvent;
+#[cfg(feature = "use_heapless")]
 use heapless::Vec;
+
+#[cfg(feature = "use_alloc")]
+extern crate alloc;
+#[cfg(feature = "use_alloc")]
+use alloc::vec::Vec;
 #[cfg(feature = "location_event")]
 use location_event::LocationEvent;
 #[cfg(feature = "magnetometer_event")]
@@ -156,18 +168,27 @@ impl TryFrom<u8> for ControllerDataPackageType {
     }
 }
 
+#[cfg(feature = "use_heapless")]
+type ParseResult<const MAX_RESULTS: usize> =
+    Vec<Result<ControllerEvent, ProtocolParseError>, MAX_RESULTS>;
+
+#[cfg(feature = "use_alloc")]
+type ParseResult<const MAX_RESULTS: usize> = Vec<Result<ControllerEvent, ProtocolParseError>>;
+#[cfg(feature = "use_alloc")]
+const MAX_RESULTS: usize = 0;
+
 /// Parse the input string for commands. Unexpected content will be ignored if it's not formatted like a command!
-pub fn parse<const MAX_RESULTS: usize>(
+pub fn parse<#[cfg(feature = "use_heapless")] const MAX_RESULTS: usize>(
     input: &[u8],
-) -> Vec<Result<ControllerEvent, ProtocolParseError>, MAX_RESULTS> {
+) -> ParseResult<MAX_RESULTS> {
     /// Simple state machine for the parser, represents whether the parser is seeking a start or has found it.
     enum ParserState {
         SeekStart,
         ParseCommand,
     }
     let mut state = ParserState::SeekStart;
 
-    let mut result: Vec<Result<ControllerEvent, ProtocolParseError>, MAX_RESULTS> = Vec::new();
+    let mut result = Vec::new();
 
     for pos in 0..input.len() {
         let byte = input[pos];
@@ -179,7 +200,11 @@ pub fn parse<const MAX_RESULTS: usize>(
             }
             ParserState::ParseCommand => {
                 let data_package = extract_and_parse_command(&input[(pos - 1)..]);
+                #[cfg(feature = "use_alloc")]
+                result.push(data_package);
+                #[cfg(feature = "use_heapless")]
                 result.push(data_package).ok();
+                #[cfg(feature = "use_heapless")]
                 if result.len() == MAX_RESULTS {
                     return result;
                 }
@@ -334,9 +359,11 @@ mod tests {
 
     #[test]
     fn test_parse() {
-        const MAX_RESULTS: usize = 4;
         let input = b"\x00!B11:!B10;\x00\x00!\x00\x00\x00\x00";
-        let result = parse::<MAX_RESULTS>(input);
+        #[cfg(feature = "use_heapless")]
+        let result = parse::<4>(input);
+        #[cfg(feature = "use_alloc")]
+        let result = parse(input);
 
         assert_eq!(result.len(), 3);
         assert_is_button_event(&result[0], Button::Button1, ButtonState::Pressed);