#!/usr/bin/env python3
import argparse
import contextlib
import functools
import os
import shutil
import subprocess
import sys
import sysconfig
import tempfile
from pathlib import Path
from textwrap import dedent
try:
from os import process_cpu_count as cpu_count
except ImportError:
from os import cpu_count
EMSCRIPTEN_DIR = Path(__file__).parent
CHECKOUT = EMSCRIPTEN_DIR.parent.parent.parent
CROSS_BUILD_DIR = CHECKOUT / "cross-build"
BUILD_DIR = CROSS_BUILD_DIR / "build"
HOST_TRIPLE = "wasm32-emscripten"
HOST_DIR = CROSS_BUILD_DIR / HOST_TRIPLE
LOCAL_SETUP = CHECKOUT / "Modules" / "Setup.local"
LOCAL_SETUP_MARKER = "# Generated by Tools/wasm/emscripten.py\n".encode("utf-8")
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 getattr(context, "clean", False) and working_dir.exists():
print("🚮 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-emscripten-",
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."""
if LOCAL_SETUP.exists():
print(f"👍 {LOCAL_SETUP} exists ...")
else:
print(f"📝 Touching {LOCAL_SETUP} ...")
LOCAL_SETUP.write_bytes(LOCAL_SETUP_MARKER)
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}")
@subdir(HOST_DIR, clean_ok=True)
def configure_emscripten_python(context, working_dir):
"""Configure the emscripten/host build."""
config_site = os.fsdecode(
CHECKOUT / "Tools" / "wasm" / "config.site-wasm32-emscripten"
)
emscripten_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"{emscripten_build_dir}/build/lib.emscripten-wasm32-{python_version}"
)
if pydebug:
sysconfig_data += "-pydebug"
host_runner = context.host_runner
env_additions = {"CONFIG_SITE": config_site, "HOSTRUNNER": host_runner}
build_python = os.fsdecode(build_python_path())
configure = [
"emconfigure",
os.path.relpath(CHECKOUT / "configure", working_dir),
"CFLAGS=-DPY_CALL_TRAMPOLINE -sUSE_BZIP2",
f"--host={HOST_TRIPLE}",
f"--build={build_platform()}",
f"--with-build-python={build_python}",
"--without-pymalloc",
"--disable-shared",
"--disable-ipv6",
"--enable-big-digits=30",
"--enable-wasm-dynamic-linking",
f"--prefix={HOST_DIR}",
]
if pydebug:
configure.append("--with-pydebug")
if context.args:
configure.extend(context.args)
call(
configure,
env=updated_env(env_additions),
quiet=context.quiet,
)
shutil.copy(EMSCRIPTEN_DIR / "node_entry.mjs", working_dir / "node_entry.mjs")
node_entry = working_dir / "node_entry.mjs"
exec_script = working_dir / "python.sh"
exec_script.write_text(
dedent(
f"""\
#!/bin/sh
# We compute our own path, not following symlinks and pass it in so that
# node_entry.mjs can set sys.executable correctly.
exec {host_runner} {node_entry} "$(realpath -s $0)" "$@"
"""
)
)
exec_script.chmod(0o755)
print(f"🏃♀️ Created {exec_script} ... ")
sys.stdout.flush()
@subdir(HOST_DIR)
def make_emscripten_python(context, working_dir):
"""Run `make` for the emscripten/host build."""
call(
["make", "--jobs", str(cpu_count()), "commoninstall"],
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_emscripten_python,
make_emscripten_python,
]
for step in steps:
step(context)
def clean_contents(context):
"""Delete all files created by this script."""
if CROSS_BUILD_DIR.exists():
print(f"🧹 Deleting {CROSS_BUILD_DIR} ...")
shutil.rmtree(CROSS_BUILD_DIR)
if LOCAL_SETUP.exists():
with LOCAL_SETUP.open("rb") as file:
if file.read(len(LOCAL_SETUP_MARKER)) == LOCAL_SETUP_MARKER:
print(f"🧹 Deleting generated {LOCAL_SETUP} ...")
def main():
default_host_runner = "node"
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/emscripten (pydebug builds are inferred from the build Python)",
)
make_host = subcommands.add_parser("make-host", help="Run `make` for the host/emscripten")
clean = subcommands.add_parser(
"clean", help="Delete files and directories created by this script"
)
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 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(
"--host-runner",
action="store",
default=default_host_runner,
dest="host_runner",
help="Command template for running the emscripten host"
f"`{default_host_runner}`)",
)
context = parser.parse_args()
dispatch = {
"configure-build-python": configure_build_python,
"make-build-python": make_build_python,
"configure-host": configure_emscripten_python,
"make-host": make_emscripten_python,
"build": build_all,
"clean": clean_contents,
}
if not context.subcommand:
# No command provided, display help and exit
print("Expected one of", ", ".join(sorted(dispatch.keys())), file=sys.stderr)
parser.print_help(sys.stderr)
sys.exit(1)
dispatch[context.subcommand](context)
if __name__ == "__main__":
main()
Codebase Browser
cpython