Add automatic, configured formatting.

.clang-format

@@ -0,0 +1,6 @@
+BasedOnStyle: LLVM
+AlignAfterOpenBracket: BlockIndent
+BinPackArguments: false
+BinPackParameters: false
+ContinuationIndentWidth: 2
+IndentWidth: 2

.envrc

@@ -1,3 +1,7 @@
 #!/usr/bin/env bash
 
+if command -v git > /dev/null && on_git_branch; then
+  git config --local core.hooksPath .githooks/
+fi
+
 use flake

.githooks/pre-commit

@@ -0,0 +1,13 @@
+#!/usr/bin/env bash
+set -e
+
+filesToFormat=$(
+  git --no-pager diff --name-status --no-color --cached | \
+    awk '$1 != "D" && $2 ~ /\.c\|\.h/ {print $NF}'
+)
+
+for path in $filesToFormat
+do
+  clang-format -i "$path"
+  git add "$path"
+done;

README.md

@@ -26,3 +26,19 @@ include:
 Once all prompts are evaluated, the keys of the object are converted into
 uppercase environment variables and passed to the `run.sh` file relative to the
 current directory.
+
+## Development
+
+This template includes an `.envrc` file for use with [direnv](https://direnv.net/).
+
+### Formatting
+
+A `pre-commit` file is included in `.githooks` to ensure consistent formatting.
+Run the following to configure `git` to use it:
+
+```bash
+git config --local core.hooksPath .githooks/
+```
+
+If running [direnv](https://direnv.net/), this is done automatically provided
+`git` is installed and a repository is initialized.