ci: port wasm build script to bash

given the prior dependency on docker, and the existence of
mingw/git bash, this doesn't change platform requirements.

Dockerfile

@@ -2,7 +2,7 @@ FROM node:22-alpine@sha256:ed9736a13b88ba55cbc08c75c9edac8ae7f72840482e40324670b
 ARG UID=1000
 ARG GID=1000
 
-RUN apk add -U clang lld wasi-sdk && mkdir /home/node/llhttp
+RUN apk add -U clang lld wasi-sdk bash && mkdir /home/node/llhttp
 
 WORKDIR /home/node/llhttp
 

bin/build_wasm.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+
+set -e
+
+WASM_SRC="$(dirname "$0")/../"
+WASM_OUT="$(dirname "$0")/../build/wasm"
+
+cd "$WASM_SRC"
+
+if [[ -z "$WASM_PLATFORM" && -n "$1" ]]; then
+    WASM_PLATFORM=$(docker info -f "{{.OSType}}/{{.Architecture}}")
+fi
+
+case "$1" in
+    --prebuild)
+        exec docker build --platform="$WASM_PLATFORM" -t llhttp_wasm_builder . --load
+        ;;
+    --setup)
+        mkdir -p build
+        exit 0
+        ;;
+    --docker)
+        cmd=(docker run --rm --platform="$WASM_PLATFORM")
+        if [[ -z "$CI" ]]; then
+            cmd+=(-it)
+        fi
+        # Try to avoid root permission problems on compiled assets
+        # when running on linux.
+        # It will work flawessly if uid === gid === 1000
+        # there will be some warnings otherwise.
+        if [[ "$(uname)" == Linux ]]; then
+            cmd+=(--user "$(id -u):$(id -g)")
+        fi
+        cmd+=(--mount "type=bind,source=./build,target=/home/node/llhttp/build" llhttp_wasm_builder npm run wasm)
+
+        echo "> ${cmd[*]}"
+        exec "${cmd[@]}"
+        ;;
+esac
+
+mkdir -p "$WASM_OUT"
+
+npm run build
+
+clang \
+    --sysroot=/usr/share/wasi-sysroot \
+    -target wasm32-unknown-wasi \
+    -Ofast \
+    -fno-exceptions \
+    -fvisibility=hidden \
+    -mexec-model=reactor \
+    -Wl,-error-limit=0 \
+    -Wl,-O3 \
+    -Wl,--lto-O3 \
+    -Wl,--strip-all \
+    -Wl,--allow-undefined \
+    -Wl,--export-dynamic \
+    -Wl,--export-table \
+    -Wl,--export=malloc \
+    -Wl,--export=free \
+    -Wl,--no-entry \
+    build/c/*.c \
+    src/native/*.c \
+    -Ibuild \
+    -o "$WASM_OUT/llhttp.wasm"
+
+cp lib/llhttp/{constants,utils}.* "$WASM_OUT/"

package.json

@@ -14,7 +14,7 @@
     "build-ts": "tsc",
     "prebuild-wasm": "npm run wasm -- --prebuild && npm run wasm -- --setup",
     "build-wasm": "npm run wasm -- --docker",
-    "wasm": "ts-node bin/build_wasm.ts",
+    "wasm": "bash bin/build_wasm.sh",
     "clean": "rm -rf lib && rm -rf test/tmp",
     "prepare": "npm run clean && npm run build-ts",
     "test": "node -r ts-node/register/type-check ./test/md-test.ts",