platform_build_soong/scripts/ninja_rsp.py

84 lines
2.4 KiB
Python

# Copyright (C) 2020 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
"""This file reads entries from a Ninja rsp file."""
class NinjaRspFileReader:
"""
Reads entries from a Ninja rsp file. Ninja escapes any entries in the file that contain a
non-standard character by surrounding the whole entry with single quotes, and then replacing
any single quotes in the entry with the escape sequence '\''.
"""
def __init__(self, filename):
self.f = open(filename, 'r')
self.r = self.character_reader(self.f)
def __iter__(self):
return self
def character_reader(self, f):
"""Turns a file into a generator that returns one character at a time."""
while True:
c = f.read(1)
if c:
yield c
else:
return
def __next__(self):
entry = self.read_entry()
if entry:
return entry
else:
raise StopIteration
def read_entry(self):
c = next(self.r, "")
if not c:
return ""
elif c == "'":
return self.read_quoted_entry()
else:
entry = c
for c in self.r:
if c == " " or c == "\n":
break
entry += c
return entry
def read_quoted_entry(self):
entry = ""
for c in self.r:
if c == "'":
# Either the end of the quoted entry, or the beginning of an escape sequence, read the next
# character to find out.
c = next(self.r)
if not c or c == " " or c == "\n":
# End of the item
return entry
elif c == "\\":
# Escape sequence, expect a '
c = next(self.r)
if c != "'":
# Malformed escape sequence
raise "malformed escape sequence %s'\\%s" % (entry, c)
entry += "'"
else:
raise "malformed escape sequence %s'%s" % (entry, c)
else:
entry += c
raise "unterminated quoted entry %s" % entry