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# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# This script generates js/public/PrefsGenerated.h from StaticPrefList.yaml
import buildconfig
import six
import yaml
from mozbuild.preprocessor import Preprocessor
HEADER_TEMPLATE = """\
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef js_PrefsGenerated_h
#define js_PrefsGenerated_h
/* This file is generated by js/src/GeneratePrefs.py. Do not edit! */
#include "mozilla/Atomics.h"
#include <stdint.h>
%(contents)s
#endif // js_PrefsGenerated_h
"""
def load_yaml(yaml_path):
# First invoke the preprocessor to handle #ifdefs in the YAML file.
pp = Preprocessor()
pp.context.update(buildconfig.defines["ALLDEFINES"])
# To make #ifdef DEBUG work, use a similar hack as in emit_code in
# generate_static_pref_list.py.
if buildconfig.substs.get("MOZ_DEBUG"):
pp.context["DEBUG"] = "1"
pp.out = six.StringIO()
pp.do_filter("substitution")
pp.do_include(yaml_path)
contents = pp.out.getvalue()
return yaml.safe_load(contents)
# Returns the C++ type to use for the pref type from the YAML file. Always use
# the non-atomic type for return values and arguments. The field type is
# determined elsewhere.
def get_cpp_type(type):
if type in ("bool", "RelaxedAtomicBool"):
return "bool"
if type in ("uint32_t", "RelaxedAtomicUint32"):
return "uint32_t"
if type in ("int32_t", "RelaxedAtomicInt32"):
return "int32_t"
raise Exception("Unexpected type: {}".format(type))
# Returns a C++ expression for the default pref value. Booleans in the YAML file
# are converted to Pythonic True or False, so those need special handling.
def get_cpp_init_value(val):
if val is True:
return "true"
if val is False:
return "false"
return str(val)
def generate_prefs_header(c_out, yaml_path):
prefs = load_yaml(yaml_path)
js_options_prefix = "javascript.options."
def is_js_pref(pref):
set_spidermonkey_pref = pref.get("set_spidermonkey_pref", False)
if set_spidermonkey_pref not in (False, "startup", "always"):
raise Exception("Invalid value for set_spidermonkey_pref")
# Ignore prefs that don't have the |set_spidermonkey_pref| attribute.
if set_spidermonkey_pref is False:
return False
# Only support prefs with javascript.options prefix.
if not pref["name"].startswith(js_options_prefix):
raise Exception("set_spidermonkey_pref only works for JS prefs")
return True
# Remove all non-JS prefs and sort prefs by name.
prefs = list(filter(is_js_pref, prefs))
prefs.sort(key=lambda pref: pref["name"])
class_fields = []
class_fields_inits = []
macro_entries = []
browser_set_statements = []
browser_set_non_startup_statements = []
for pref in prefs:
name = pref["name"]
name = name[len(js_options_prefix) :]
is_startup_pref = pref["set_spidermonkey_pref"] == "startup"
cpp_name = name.replace(".", "_").replace("-", "_")
type = get_cpp_type(pref["type"])
init_value = get_cpp_init_value(pref["value"])
setter_name = ("setAtStartup_" if is_startup_pref else "set_") + cpp_name
# Use a relaxed atomic for non-startup prefs because those might be changed
# after startup.
field_type = type
if not is_startup_pref:
field_type = "mozilla::Atomic<{}, mozilla::Relaxed>".format(field_type)
class_fields.append("static {} {}_;".format(field_type, cpp_name))
class_fields_inits.append(
"{} JS::Prefs::{}_{{{}}};".format(field_type, cpp_name, init_value)
)
is_startup_pref_bool = "true" if is_startup_pref else "false"
# Generate a MACRO invocation like this:
# MACRO("arraybuffer_transfer", arraybuffer_transfer, bool, setAtStartup_arraybuffer_transfer, true)
macro_entries.append(
'MACRO("{}", {}, {}, {}, {})'.format(
name, cpp_name, type, setter_name, is_startup_pref_bool
)
)
# Generate a C++ statement to set the JS pref based on Gecko's StaticPrefs:
# JS::Prefs::setAtStartup_foo(StaticPrefs::javascript_options_foo());
browser_pref_cpp_name = pref["name"].replace(".", "_").replace("-", "_")
if pref.get("do_not_use_directly", False):
browser_pref_cpp_name += "_DoNotUseDirectly"
statement = "JS::Prefs::{}(mozilla::StaticPrefs::{}());".format(
setter_name, browser_pref_cpp_name
)
browser_set_statements.append(statement)
# For non-startup prefs, also generate code to update the pref after startup.
if not is_startup_pref:
browser_set_non_startup_statements.append(statement)
contents = ""
contents += "#define JS_PREF_CLASS_FIELDS \\\n"
contents += "".join(map(lambda s: " {}\\\n".format(s), class_fields))
contents += "\n\n"
contents += "#define JS_PREF_CLASS_FIELDS_INIT \\\n"
contents += "".join(map(lambda s: " {}\\\n".format(s), class_fields_inits))
contents += "\n\n"
contents += "#define FOR_EACH_JS_PREF(MACRO) \\\n"
contents += "".join(map(lambda s: " {}\\\n".format(s), macro_entries))
contents += "\n\n"
contents += "#define SET_JS_PREFS_FROM_BROWSER_PREFS \\\n"
contents += "".join(map(lambda s: " {}\\\n".format(s), browser_set_statements))
contents += "\n\n"
contents += "#define SET_NON_STARTUP_JS_PREFS_FROM_BROWSER_PREFS \\\n"
contents += "".join(
map(lambda s: " {}\\\n".format(s), browser_set_non_startup_statements)
)
contents += "\n\n"
c_out.write(
HEADER_TEMPLATE
% {
"contents": contents,
}
)