Add browser runtime, Emscripten build, and persistent submodule updates

.github/workflows/build-browser.yml

@@ -0,0 +1,109 @@
+name: Build browser runtime
+
+permissions:
+  contents: write
+
+on:
+  workflow_dispatch:
+  push:
+    paths:
+      - "os/main.c"
+      - "os/wasm-rtos"
+      - ".gitmodules"
+      - "build-browser.sh"
+      - ".github/workflows/build-browser.yml"
+  pull_request:
+    paths:
+      - "os/main.c"
+      - "os/wasm-rtos"
+      - ".gitmodules"
+      - "build-browser.sh"
+      - ".github/workflows/build-browser.yml"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ github.head_ref || github.ref_name }}
+          fetch-depth: 0
+          submodules: false
+
+      - name: Update wasm-rtos and nested wasm3 submodules
+        run: |
+          git submodule sync --recursive
+          git submodule update --init --remote --recursive
+          git submodule status --recursive
+
+          test -f os/wasm-rtos/os.c
+          test -f os/wasm-rtos/wasm3/source/wasm3.h
+
+          echo "wasm-rtos commit: $(git -C os/wasm-rtos rev-parse HEAD)"
+          echo "wasm3 commit: $(git -C os/wasm-rtos/wasm3 rev-parse HEAD)"
+
+          if ! git -C os/wasm-rtos diff --quiet -- wasm3; then
+            echo "::warning::The nested wasm3 checkout is newer than the gitlink recorded by wasm-rtos. It is used by this build, but must be committed in the wasm-rtos repository to become permanent."
+          fi
+
+      - name: Install latest Emscripten SDK
+        run: |
+          git clone --depth 1 https://github.com/emscripten-core/emsdk.git "$RUNNER_TEMP/emsdk" >/dev/null
+          "$RUNNER_TEMP/emsdk/emsdk" install latest >"$RUNNER_TEMP/emsdk-install.log"
+          "$RUNNER_TEMP/emsdk/emsdk" activate latest >>"$RUNNER_TEMP/emsdk-install.log"
+          source "$RUNNER_TEMP/emsdk/emsdk_env.sh" >/dev/null
+          emcc --version
+
+      - name: Build JavaScript and WebAssembly runtime
+        run: |
+          source "$RUNNER_TEMP/emsdk/emsdk_env.sh" >/dev/null
+          if ! bash ./build-browser.sh >build-browser.log 2>&1; then
+            echo "Browser runtime compilation failed:"
+            tail -n 100 build-browser.log
+            exit 1
+          fi
+          tail -n 100 build-browser.log
+
+      - name: Upload browser build log
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: browser-build-log
+          path: build-browser.log
+          if-no-files-found: warn
+
+      - name: Verify browser runtime outputs
+        run: |
+          test -s os/wasm-rtos.js
+          test -s os/wasm-rtos.wasm
+          test "$(od -An -tx1 -N4 os/wasm-rtos.wasm | tr -d ' \n')" = "0061736d"
+          grep -q "createWasmRtosModule" os/wasm-rtos.js
+          ls -lh os/wasm-rtos.js os/wasm-rtos.wasm
+
+      - name: Persist updated wasm-rtos submodule
+        if: github.event_name == 'push'
+        run: |
+          branch="${{ github.ref_name }}"
+
+          git config user.name "github-actions[bot]"
+          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+          git add os/wasm-rtos
+
+          if git diff --cached --quiet; then
+            echo "No wasm-rtos submodule pointer changed"
+            exit 0
+          fi
+
+          git commit -m "Update wasm-rtos submodule"
+          git push origin "HEAD:$branch"
+
+      - name: Upload browser runtime
+        uses: actions/upload-artifact@v4
+        with:
+          name: wasm-rtos-browser
+          path: |
+            os/wasm-rtos.js
+            os/wasm-rtos.wasm
+          if-no-files-found: error

build-browser.sh

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+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "$0")" && pwd)"
+cd "$ROOT"
+
+EMCC_BIN="${EMCC:-emcc}"
+OUTPUT_JS="os/wasm-rtos.js"
+OUTPUT_WASM="os/wasm-rtos.wasm"
+WASM_RTOS_DIR="os/wasm-rtos"
+WASM3_SOURCE_DIR="$WASM_RTOS_DIR/wasm3/source"
+
+if ! command -v "$EMCC_BIN" >/dev/null 2>&1; then
+    echo "FAIL Emscripten compiler not found: $EMCC_BIN"
+    exit 1
+fi
+
+required_files=(
+    "os/main.c"
+    "$WASM_RTOS_DIR/os.c"
+    "$WASM_RTOS_DIR/os.h"
+    "$WASM_RTOS_DIR/hal.h"
+)
+
+for required_file in "${required_files[@]}"; do
+    if [ ! -f "$required_file" ]; then
+        echo "FAIL required source file is missing: $required_file"
+        exit 1
+    fi
+done
+
+if [ ! -d "$WASM3_SOURCE_DIR" ]; then
+    echo "FAIL wasm3 source directory is missing: $WASM3_SOURCE_DIR"
+    exit 1
+fi
+
+mapfile -t wasm3_sources < <(find "$WASM3_SOURCE_DIR" -maxdepth 1 -type f -name '*.c' -print | sort)
+if [ "${#wasm3_sources[@]}" -eq 0 ]; then
+    echo "FAIL no wasm3 C sources found in $WASM3_SOURCE_DIR"
+    exit 1
+fi
+
+exported_functions='["_main","_malloc","_free","_browser_runtime_init","_browser_runtime_shutdown","_browser_task_create","_browser_task_delete","_browser_task_suspend","_browser_task_resume","_browser_task_set_priority","_browser_runtime_step","_browser_runtime_set_slices_per_frame","_browser_task_get_state","_browser_task_get_priority","_browser_task_get_run_count","_browser_task_get_exit_reason","_browser_task_get_exit_code","_browser_runtime_get_task_count","_browser_runtime_get_ready_task_count","_browser_runtime_get_waiting_task_count","_browser_runtime_get_last_error"]'
+exported_runtime_methods='["ccall","cwrap","UTF8ToString"]'
+
+rm -f "$OUTPUT_JS" "$OUTPUT_WASM"
+
+"$EMCC_BIN" \
+    -std=c11 \
+    -O2 \
+    -Wall \
+    -Wextra \
+    -D_GNU_SOURCE \
+    -Dd_m3HasWASI \
+    -I. \
+    -I"$WASM_RTOS_DIR" \
+    -I"$WASM3_SOURCE_DIR" \
+    os/main.c \
+    "$WASM_RTOS_DIR/os.c" \
+    "${wasm3_sources[@]}" \
+    -sWASM=1 \
+    -sALLOW_MEMORY_GROWTH=1 \
+    -sNO_EXIT_RUNTIME=1 \
+    -sMODULARIZE=1 \
+    -sEXPORT_NAME=createWasmRtosModule \
+    -sENVIRONMENT=web \
+    -sEXPORTED_FUNCTIONS="$exported_functions" \
+    -sEXPORTED_RUNTIME_METHODS="$exported_runtime_methods" \
+    -o "$OUTPUT_JS"
+
+if [ ! -s "$OUTPUT_JS" ]; then
+    echo "FAIL generated JavaScript loader is missing or empty: $OUTPUT_JS"
+    exit 1
+fi
+
+if [ ! -s "$OUTPUT_WASM" ]; then
+    echo "FAIL generated WebAssembly runtime is missing or empty: $OUTPUT_WASM"
+    exit 1
+fi
+
+echo "Generated browser runtime:"
+ls -lh "$OUTPUT_JS" "$OUTPUT_WASM"