pandemonium_engine/platform_methods.py

82 lines
2.8 KiB
Python

import os
import sys
import json
import uuid
import functools
import subprocess
# NOTE: The multiprocessing module is not compatible with SCons due to conflict on cPickle
if sys.version_info[0] < 3:
JSON_SERIALIZABLE_TYPES = (bool, int, long, float, basestring)
else:
JSON_SERIALIZABLE_TYPES = (bool, int, float, str)
def run_in_subprocess(builder_function):
@functools.wraps(builder_function)
def wrapper(target, source, env):
# Convert SCons Node instances to absolute paths
target = [node.srcnode().abspath for node in target]
source = [node.srcnode().abspath for node in source]
# Short circuit on non-Windows platforms, no need to run in subprocess
if sys.platform not in ("win32", "cygwin"):
return builder_function(target, source, env)
# Identify module
module_name = builder_function.__module__
function_name = builder_function.__name__
module_path = sys.modules[module_name].__file__
if module_path.endswith(".pyc") or module_path.endswith(".pyo"):
module_path = module_path[:-1]
# Subprocess environment
subprocess_env = os.environ.copy()
subprocess_env["PYTHONPATH"] = os.pathsep.join([os.getcwd()] + sys.path)
# Keep only JSON serializable environment items
filtered_env = dict((key, value) for key, value in env.items() if isinstance(value, JSON_SERIALIZABLE_TYPES))
# Save parameters
args = (target, source, filtered_env)
data = dict(fn=function_name, args=args)
json_path = os.path.join(os.environ["TMP"], uuid.uuid4().hex + ".json")
with open(json_path, "wt") as json_file:
json.dump(data, json_file, indent=2)
json_file_size = os.stat(json_path).st_size
print(
"Executing builder function in subprocess: "
"module_path=%r, parameter_file=%r, parameter_file_size=%r, target=%r, source=%r"
% (module_path, json_path, json_file_size, target, source)
)
try:
exit_code = subprocess.call([sys.executable, module_path, json_path], env=subprocess_env)
finally:
try:
os.remove(json_path)
except (OSError, IOError) as e:
# Do not fail the entire build if it cannot delete a temporary file
print(
"WARNING: Could not delete temporary file: path=%r; [%s] %s" % (json_path, e.__class__.__name__, e)
)
# Must succeed
if exit_code:
raise RuntimeError(
"Failed to run builder function in subprocess: module_path=%r; data=%r" % (module_path, data)
)
return wrapper
def subprocess_main(namespace):
with open(sys.argv[1]) as json_file:
data = json.load(json_file)
fn = namespace[data["fn"]]
fn(*data["args"])