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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
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
# This script processes NSS .def files according to the rules defined in
# a comment at the top of each one. The files are used to define the
# exports from NSS shared libraries, with -DEFFILE on Windows, a linker
# script on Linux, or with -exported_symbols_list on OS X.
# The NSS build system processes them using a series of sed replacements,
# but the Mozilla build system is already running a Python script to generate
# the file so it's simpler to just do the replacement in Python.
# One difference between the NSS build system and Mozilla's is that
# Mozilla's supports building on Linux for Windows using MinGW. MinGW
# expects all lines containing ;+ removed and all ;- tokens removed.
def main(output, input):
is_darwin = buildconfig.substs["OS_ARCH"] == "Darwin"
is_mingw = "WINNT" == buildconfig.substs["OS_ARCH"] and buildconfig.substs.get(
with open(input, "r", encoding="utf-8") as f:
for line in f:
line = line.rstrip()
# On everything except MinGW, remove all lines containing ';-'
if not is_mingw and ";-" in line:
# On OS X, remove all lines containing ';+'
if is_darwin and ";+" in line:
# Remove the string ' DATA '.
line = line.replace(" DATA ", "")
# Remove the string ';+'
if not is_mingw:
line = line.replace(";+", "")
# Remove the string ';;'
line = line.replace(";;", "")
# If a ';' is present, remove everything after it,
# and on OS X, remove it as well.
i = line.find(";")
if i != -1:
if is_darwin or is_mingw:
line = line[:i]
line = line[: i + 1]
# On OS X, symbols get an underscore in front.
if line and is_darwin: