Add astyle and enforce in CI

.astylerc

@@ -0,0 +1,12 @@
+--style=google
+--indent=spaces
+--indent-preproc-define
+--indent-preproc-cond
+--pad-oper
+--pad-comma
+--pad-header
+--align-pointer=name
+--add-braces
+--convert-tabs
+--mode=c
+--suffix=none

.codespellrc

@@ -0,0 +1,5 @@
+[codespell]
+skip = .direnv,.git,libopencm3
+ignore-words = ./dev-support/codespell-ignore-words
+check-filenames =
+check-hidden =

.envrc

@@ -0,0 +1,5 @@
+if ! has nix_direnv_version || ! nix_direnv_version 3.0.3; then
+  source_url "https://raw.githubusercontent.com/nix-community/nix-direnv/3.0.3/direnvrc" "sha256-0EVQVNSRQWsln+rgPW3mXVmnF5sfcmKEYOmOSfLYxHg="
+fi
+
+use flake

.github/workflows/build.yaml

@@ -0,0 +1,48 @@
+name: Build
+on:
+  push:
+    branches: [ '*' ]
+  pull_request:
+    branches: [ "main" ]
+jobs:
+  build_test:
+    runs-on: ubuntu-latest
+    steps:
+    - name: install jq
+      shell: bash
+      run: |
+        if ! (command -v jq) &> /dev/null
+        then
+          sudo apt install -y --no-install-recommends jq
+        fi
+    - uses: actions/checkout@v4
+    - id: nixpkgs
+      shell: bash
+      run: |
+        if [ -f flake.lock ]; then
+          nixpkgs="flake:$(cat flake.lock | jq -r '.nodes.nixpkgs.locked // empty | .type + ":" + .owner + "/" + .repo + "/" + .rev')"
+        else
+          nixpkgs=channel:nixos-unstable
+        fi
+        echo "nixpkgs=$nixpkgs" >> "$GITHUB_OUTPUT"
+    - uses: cachix/install-nix-action@v25
+      with:
+        nix_path: nixpkgs=${{ steps.nixpkgs.outputs.nixpkgs }}
+    - name: Prepare nix dev shell
+      shell: nix develop .#ci -c bash -e {0}
+      run: |
+          astyle --version
+    - name: Astyle
+      shell: nix develop .#ci -c bash -e {0}
+      run: |
+          err=$(astyle $(git ls-files "*.c" "*.h") --options=.astylerc --dry-run --formatted)
+          if [[ ${#err} != 0 ]]; then
+            echo "$err" | awk '{split($0,a);print a[2]}' | while IFS= read -r file; do
+              echo "::error file={"$file"},title={checking}::Formatted $file"
+            done
+            exit 1
+          fi
+    - name: Build targets
+      shell: nix develop .#ci -c bash -e {0}
+      run: |
+          make

.gitignore

@@ -3,6 +3,7 @@
 
 .vscode
 .idea
+.direnv
 obj
 elf
 bin

README.md

@@ -53,6 +53,18 @@ If you are a potential consumer of **MLKEM-C-EMBEDDED**, please reach out to us.
 We're interested in hearing the way you are considering using **MLKEM-C-EMBEDDED** and could benefit from additional features.
 If you have specific feature requests, please open an issue.
 
+## Environment Setup
+
+All the develop and build dependencies are specified in [flake.nix](flake.nix). 
+
+- Setup with nix,
+    - Running `nix develop` will execute a bash shell with the development environment specified in [flake.nix](flake.nix).
+    - Alternatively, you can enable `direnv` by using `direnv allow`, allowing it to handle the environment setup for you.
+
+- If your're not using nix, please ensure you have installed the same version as specified in [flake.nix](flake.nix).
+
+For further details, please refer to [DevSupport](dev-support/)
+
 ## Running tests and benchmarks
 
 The build system compiles tests and benchmarks for each mlkem parameter set on specified platform (currently only `stm32f4discovery` is supported).

dev-support/README.md

@@ -0,0 +1,22 @@
+[//]: # (SPDX-License-Identifier: CC-BY-4.0)
+
+# Dev Support
+
+## Recommended Prerequisites
+
+### [direnv](https://direnv.net/)
+
+Enabling `direnv` would greatly enhance the development experience. Once enabled, all dependencies will be installed, and the shell will be augmented according to the specifications in [flake.nix](../flake.nix) whenever you enter the project directory from your shell. The initial setup might take a bit longer when entering the project directory for the first time.
+
+`direnv` can be enabled or disabled using `direnv allow` and `direnv deny` respectively. If you're new to `direnv`, it is also recommended to [integrate it with your shell](https://direnv.net/docs/hook.html) first.
+
+### Formatter and Linter
+- `nixpkgs-fmt` and `deadnix` for `Nix`
+- `shfmt` and `shellcheck` for shell script
+- `astyle` for .c, .h files
+
+### Tools
+
+When used together with direnv, the tools should be automatically discoverable by the shell.
+
+- [style](bin/style): Formatting, linting and spell checking all files

dev-support/bin/log

@@ -0,0 +1,49 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: Apache-2.0
+
+RED="$(tput setaf 1)"
+GREEN="$(tput setaf 2)"
+YELLOW3="$(tput setaf 148)"
+BLUE="$(tput setaf 4)"
+GREY54="$(tput setaf 249)"
+NORMAL="$(tput sgr0)"
+
+export RED
+export GREEN
+export YELLOW3
+export BLUE
+export GREY54
+export NORMAL
+# UNDERLINE=$(tput smul)
+
+# export to avoid lsp warning
+export DEBUG="${BLUE}DEBUG"
+export INFO="${GREEN}INFO"
+export WARN="${YELLOW3}WARN"
+export ERROR="${RED}ERROR"
+
+log()
+{
+  local level="${FUNCNAME[1]^^}"
+  printf "%s\t%s\t%b\n" "${GREY54}$(date "+%T")" "${!level}" "${*}"
+}
+
+debug()
+{
+  log "${NORMAL}${*}"
+}
+
+info()
+{
+  log "${NORMAL}${*}"
+}
+
+warn()
+{
+  log "${NORMAL}${*}" 1>&2
+}
+
+error()
+{
+  log "${NORMAL}${*}" 1>&2
+}

dev-support/bin/style

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: Apache-2.0
+
+set -o errexit
+set -o errtrace
+set -o nounset
+set -o pipefail
+
+ROOT="$(realpath "$(dirname "$0")"/../../)"
+DEVSUPPORT="$(realpath "$(dirname "$0")"/../)"
+CURDIR="$(realpath "$(dirname "$0")")"
+. "$CURDIR/log"
+
+info "Formatting nix files"
+nixpkgs-fmt "$ROOT"
+
+info "Formatting shell scripts"
+# shellcheck disable=SC2046
+shfmt -s -w -l -i 2 -ci -fn $(shfmt -f $(git grep -l '' :/))
+
+info "Chekcking misspellings"
+codespell --skip "$ROOT/.direnv,$ROOT/.git,$ROOT/libopencm3" --ignore-words "$DEVSUPPORT/codespell-ignore-words" "$ROOT"
+
+info "Formatting c files"
+# shellcheck disable=SC2046
+astyle $(git ls-files ":/*.c" ":/*.h") --options="$ROOT/.astylerc" --formatted

dev-support/codespell-ignore-words

@@ -0,0 +1,3 @@
+ake
+ege
+hsi