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Diffstat (limited to 'Tools/wasm/wasi.py')
| -rw-r--r-- | Tools/wasm/wasi.py | 328 |
1 files changed, 328 insertions, 0 deletions
diff --git a/Tools/wasm/wasi.py b/Tools/wasm/wasi.py new file mode 100644 index 00000000000..34c0e9375e2 --- /dev/null +++ b/Tools/wasm/wasi.py @@ -0,0 +1,328 @@ +#!/usr/bin/env python3 + +import argparse +import contextlib +import functools +import os +try: + from os import process_cpu_count as cpu_count +except ImportError: + from os import cpu_count +import pathlib +import shutil +import subprocess +import sys +import sysconfig +import tempfile + + +CHECKOUT = pathlib.Path(__file__).parent.parent.parent +CROSS_BUILD_DIR = CHECKOUT / "cross-build" +BUILD_DIR = CROSS_BUILD_DIR / "build" +HOST_TRIPLE = "wasm32-wasi" +HOST_DIR = CROSS_BUILD_DIR / HOST_TRIPLE + + +def updated_env(updates={}): + """Create a new dict representing the environment to use. + + The changes made to the execution environment are printed out. + """ + env_defaults = {} + # https://reproducible-builds.org/docs/source-date-epoch/ + git_epoch_cmd = ["git", "log", "-1", "--pretty=%ct"] + try: + epoch = subprocess.check_output(git_epoch_cmd, encoding="utf-8").strip() + env_defaults["SOURCE_DATE_EPOCH"] = epoch + except subprocess.CalledProcessError: + pass # Might be building from a tarball. + # This layering lets SOURCE_DATE_EPOCH from os.environ takes precedence. + environment = env_defaults | os.environ | updates + + env_diff = {} + for key, value in environment.items(): + if os.environ.get(key) != value: + env_diff[key] = value + + print("🌎 Environment changes:") + for key in sorted(env_diff.keys()): + print(f" {key}={env_diff[key]}") + + return environment + + +def subdir(working_dir, *, clean_ok=False): + """Decorator to change to a working directory.""" + def decorator(func): + @functools.wraps(func) + def wrapper(context): + try: + tput_output = subprocess.check_output(["tput", "cols"], + encoding="utf-8") + terminal_width = int(tput_output.strip()) + except subprocess.CalledProcessError: + terminal_width = 80 + print("⎯" * terminal_width) + print("📁", working_dir) + if clean_ok and context.clean and working_dir.exists(): + print(f"🚮 Deleting directory (--clean)...") + shutil.rmtree(working_dir) + + working_dir.mkdir(parents=True, exist_ok=True) + + with contextlib.chdir(working_dir): + return func(context, working_dir) + + return wrapper + + return decorator + + +def call(command, *, quiet, **kwargs): + """Execute a command. + + If 'quiet' is true, then redirect stdout and stderr to a temporary file. + """ + print("❯", " ".join(map(str, command))) + if not quiet: + stdout = None + stderr = None + else: + stdout = tempfile.NamedTemporaryFile("w", encoding="utf-8", + delete=False, + prefix="cpython-wasi-", + suffix=".log") + stderr = subprocess.STDOUT + print(f"📝 Logging output to {stdout.name} (--quiet)...") + + subprocess.check_call(command, **kwargs, stdout=stdout, stderr=stderr) + + +def build_platform(): + """The name of the build/host platform.""" + # Can also be found via `config.guess`.` + return sysconfig.get_config_var("BUILD_GNU_TYPE") + + +def build_python_path(): + """The path to the build Python binary.""" + binary = BUILD_DIR / "python" + if not binary.is_file(): + binary = binary.with_suffix(".exe") + if not binary.is_file(): + raise FileNotFoundError("Unable to find `python(.exe)` in " + f"{BUILD_DIR}") + + return binary + + +@subdir(BUILD_DIR, clean_ok=True) +def configure_build_python(context, working_dir): + """Configure the build/host Python.""" + local_setup = CHECKOUT / "Modules" / "Setup.local" + if local_setup.exists(): + print(f"👍 {local_setup} exists ...") + else: + print(f"📝 Touching {local_setup} ...") + local_setup.touch() + + configure = [os.path.relpath(CHECKOUT / 'configure', working_dir)] + if context.args: + configure.extend(context.args) + + call(configure, quiet=context.quiet) + + +@subdir(BUILD_DIR) +def make_build_python(context, working_dir): + """Make/build the build Python.""" + call(["make", "--jobs", str(cpu_count()), "all"], + quiet=context.quiet) + + binary = build_python_path() + cmd = [binary, "-c", + "import sys; " + "print(f'{sys.version_info.major}.{sys.version_info.minor}')"] + version = subprocess.check_output(cmd, encoding="utf-8").strip() + + print(f"🎉 {binary} {version}") + + +def find_wasi_sdk(): + """Find the path to wasi-sdk.""" + if wasi_sdk_path := os.environ.get("WASI_SDK_PATH"): + return pathlib.Path(wasi_sdk_path) + elif (default_path := pathlib.Path("/opt/wasi-sdk")).exists(): + return default_path + + +def wasi_sdk_env(context): + """Calculate environment variables for building with wasi-sdk.""" + wasi_sdk_path = context.wasi_sdk_path + sysroot = wasi_sdk_path / "share" / "wasi-sysroot" + env = {"CC": "clang", "CPP": "clang-cpp", "CXX": "clang++", + "LDSHARED": "wasm-ld", "AR": "llvm-ar", "RANLIB": "ranlib"} + + for env_var, binary_name in list(env.items()): + env[env_var] = os.fsdecode(wasi_sdk_path / "bin" / binary_name) + + if wasi_sdk_path != pathlib.Path("/opt/wasi-sdk"): + for compiler in ["CC", "CPP", "CXX"]: + env[compiler] += f" --sysroot={sysroot}" + + env["PKG_CONFIG_PATH"] = "" + env["PKG_CONFIG_LIBDIR"] = os.pathsep.join( + map(os.fsdecode, + [sysroot / "lib" / "pkgconfig", + sysroot / "share" / "pkgconfig"])) + env["PKG_CONFIG_SYSROOT_DIR"] = os.fsdecode(sysroot) + + env["WASI_SDK_PATH"] = os.fsdecode(wasi_sdk_path) + env["WASI_SYSROOT"] = os.fsdecode(sysroot) + + env["PATH"] = os.pathsep.join([os.fsdecode(wasi_sdk_path / "bin"), + os.environ["PATH"]]) + + return env + + +@subdir(HOST_DIR, clean_ok=True) +def configure_wasi_python(context, working_dir): + """Configure the WASI/host build.""" + if not context.wasi_sdk_path or not context.wasi_sdk_path.exists(): + raise ValueError("WASI-SDK not found; " + "download from " + "https://github.com/WebAssembly/wasi-sdk and/or " + "specify via $WASI_SDK_PATH or --wasi-sdk") + + config_site = os.fsdecode(CHECKOUT / "Tools" / "wasm" / "config.site-wasm32-wasi") + + wasi_build_dir = working_dir.relative_to(CHECKOUT) + + python_build_dir = BUILD_DIR / "build" + lib_dirs = list(python_build_dir.glob("lib.*")) + assert len(lib_dirs) == 1, f"Expected a single lib.* directory in {python_build_dir}" + lib_dir = os.fsdecode(lib_dirs[0]) + pydebug = lib_dir.endswith("-pydebug") + python_version = lib_dir.removesuffix("-pydebug").rpartition("-")[-1] + sysconfig_data = f"{wasi_build_dir}/build/lib.wasi-wasm32-{python_version}" + if pydebug: + sysconfig_data += "-pydebug" + + # Use PYTHONPATH to include sysconfig data which must be anchored to the + # WASI guest's `/` directory. + host_runner = context.host_runner.format(GUEST_DIR="/", + HOST_DIR=CHECKOUT, + ENV_VAR_NAME="PYTHONPATH", + ENV_VAR_VALUE=f"/{sysconfig_data}", + PYTHON_WASM=working_dir / "python.wasm") + env_additions = {"CONFIG_SITE": config_site, "HOSTRUNNER": host_runner} + build_python = os.fsdecode(build_python_path()) + # The path to `configure` MUST be relative, else `python.wasm` is unable + # to find the stdlib due to Python not recognizing that it's being + # executed from within a checkout. + configure = [os.path.relpath(CHECKOUT / 'configure', working_dir), + f"--host={HOST_TRIPLE}", + f"--build={build_platform()}", + f"--with-build-python={build_python}"] + if pydebug: + configure.append("--with-pydebug") + if context.args: + configure.extend(context.args) + call(configure, + env=updated_env(env_additions | wasi_sdk_env(context)), + quiet=context.quiet) + + exec_script = working_dir / "python.sh" + with exec_script.open("w", encoding="utf-8") as file: + file.write(f'#!/bin/sh\nexec {host_runner} "$@"\n') + exec_script.chmod(0o755) + print(f"🏃♀️ Created {exec_script} ... ") + sys.stdout.flush() + + +@subdir(HOST_DIR) +def make_wasi_python(context, working_dir): + """Run `make` for the WASI/host build.""" + call(["make", "--jobs", str(cpu_count()), "all"], + env=updated_env(), + quiet=context.quiet) + + exec_script = working_dir / "python.sh" + subprocess.check_call([exec_script, "--version"]) + + +def build_all(context): + """Build everything.""" + steps = [configure_build_python, make_build_python, configure_wasi_python, + make_wasi_python] + for step in steps: + step(context) + + +def main(): + default_host_runner = (f"{shutil.which('wasmtime')} run " + # Make sure the stack size will work for a pydebug + # build. + # The 8388608 value comes from `ulimit -s` under Linux + # which equates to 8291 KiB. + "--wasm max-wasm-stack=8388608 " + # Enable thread support. + "--wasm threads=y --wasi threads=y " + # Map the checkout to / to load the stdlib from /Lib. + "--dir {HOST_DIR}::{GUEST_DIR} " + # Set PYTHONPATH to the sysconfig data. + "--env {ENV_VAR_NAME}={ENV_VAR_VALUE} " + # Path to the WASM binary. + "{PYTHON_WASM}") + + parser = argparse.ArgumentParser() + subcommands = parser.add_subparsers(dest="subcommand") + build = subcommands.add_parser("build", help="Build everything") + configure_build = subcommands.add_parser("configure-build-python", + help="Run `configure` for the " + "build Python") + make_build = subcommands.add_parser("make-build-python", + help="Run `make` for the build Python") + configure_host = subcommands.add_parser("configure-host", + help="Run `configure` for the " + "host/WASI (pydebug builds " + "are inferred from the build " + "Python)") + make_host = subcommands.add_parser("make-host", + help="Run `make` for the host/WASI") + for subcommand in build, configure_build, make_build, configure_host, make_host: + subcommand.add_argument("--quiet", action="store_true", default=False, + dest="quiet", + help="Redirect output from subprocesses to a log file") + for subcommand in build, configure_build, configure_host: + subcommand.add_argument("--clean", action="store_true", default=False, + dest="clean", + help="Delete any relevant directories before building") + for subcommand in build, configure_build, configure_host: + subcommand.add_argument("args", nargs="*", + help="Extra arguments to pass to `configure`") + for subcommand in build, configure_host: + subcommand.add_argument("--wasi-sdk", type=pathlib.Path, + dest="wasi_sdk_path", + default=find_wasi_sdk(), + help="Path to wasi-sdk; defaults to " + "$WASI_SDK_PATH or /opt/wasi-sdk") + subcommand.add_argument("--host-runner", action="store", + default=default_host_runner, dest="host_runner", + help="Command template for running the WebAssembly " + "code (default meant for wasmtime 14 or newer: " + f"`{default_host_runner}`)") + + context = parser.parse_args() + + dispatch = {"configure-build-python": configure_build_python, + "make-build-python": make_build_python, + "configure-host": configure_wasi_python, + "make-host": make_wasi_python, + "build": build_all} + dispatch[context.subcommand](context) + + +if __name__ == "__main__": + main() |