Add ndk api parser for ndk api coverage.

Test: m test_ndk_api_coverage_parser

Change-Id: I7be4f505757b1ca915de5e378952f8b104e1d362
diff --git a/cc/scriptlib/Android.bp b/cc/scriptlib/Android.bp
new file mode 100644
index 0000000..daebfe1
--- /dev/null
+++ b/cc/scriptlib/Android.bp
@@ -0,0 +1,23 @@
+//
+// 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.
+//
+
+python_test_host {
+    name: "test_ndk_api_coverage_parser",
+    main: "test_ndk_api_coverage_parser.py",
+    srcs: [
+        "test_ndk_api_coverage_parser.py",
+    ],
+}
diff --git a/cc/scriptlib/__init__.py b/cc/scriptlib/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/cc/scriptlib/__init__.py
diff --git a/cc/scriptlib/gen_stub_libs.py b/cc/scriptlib/gen_stub_libs.py
new file mode 100755
index 0000000..d61dfbb
--- /dev/null
+++ b/cc/scriptlib/gen_stub_libs.py
@@ -0,0 +1,507 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2016 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.
+#
+"""Generates source for stub shared libraries for the NDK."""
+import argparse
+import json
+import logging
+import os
+import re
+import sys
+
+
+ALL_ARCHITECTURES = (
+    'arm',
+    'arm64',
+    'x86',
+    'x86_64',
+)
+
+
+# Arbitrary magic number. We use the same one in api-level.h for this purpose.
+FUTURE_API_LEVEL = 10000
+
+
+def logger():
+    """Return the main logger for this module."""
+    return logging.getLogger(__name__)
+
+
+def get_tags(line):
+    """Returns a list of all tags on this line."""
+    _, _, all_tags = line.strip().partition('#')
+    return [e for e in re.split(r'\s+', all_tags) if e.strip()]
+
+
+def is_api_level_tag(tag):
+    """Returns true if this tag has an API level that may need decoding."""
+    if tag.startswith('introduced='):
+        return True
+    if tag.startswith('introduced-'):
+        return True
+    if tag.startswith('versioned='):
+        return True
+    return False
+
+
+def decode_api_level_tags(tags, api_map):
+    """Decodes API level code names in a list of tags.
+
+    Raises:
+        ParseError: An unknown version name was found in a tag.
+    """
+    for idx, tag in enumerate(tags):
+        if not is_api_level_tag(tag):
+            continue
+        name, value = split_tag(tag)
+
+        try:
+            decoded = str(decode_api_level(value, api_map))
+            tags[idx] = '='.join([name, decoded])
+        except KeyError:
+            raise ParseError('Unknown version name in tag: {}'.format(tag))
+    return tags
+
+
+def split_tag(tag):
+    """Returns a key/value tuple of the tag.
+
+    Raises:
+        ValueError: Tag is not a key/value type tag.
+
+    Returns: Tuple of (key, value) of the tag. Both components are strings.
+    """
+    if '=' not in tag:
+        raise ValueError('Not a key/value tag: ' + tag)
+    key, _, value = tag.partition('=')
+    return key, value
+
+
+def get_tag_value(tag):
+    """Returns the value of a key/value tag.
+
+    Raises:
+        ValueError: Tag is not a key/value type tag.
+
+    Returns: Value part of tag as a string.
+    """
+    return split_tag(tag)[1]
+
+
+def version_is_private(version):
+    """Returns True if the version name should be treated as private."""
+    return version.endswith('_PRIVATE') or version.endswith('_PLATFORM')
+
+
+def should_omit_version(version, arch, api, llndk, apex):
+    """Returns True if the version section should be ommitted.
+
+    We want to omit any sections that do not have any symbols we'll have in the
+    stub library. Sections that contain entirely future symbols or only symbols
+    for certain architectures.
+    """
+    if version_is_private(version.name):
+        return True
+    if 'platform-only' in version.tags:
+        return True
+
+    no_llndk_no_apex = 'llndk' not in version.tags and 'apex' not in version.tags
+    keep = no_llndk_no_apex or \
+           ('llndk' in version.tags and llndk) or \
+           ('apex' in version.tags and apex)
+    if not keep:
+        return True
+    if not symbol_in_arch(version.tags, arch):
+        return True
+    if not symbol_in_api(version.tags, arch, api):
+        return True
+    return False
+
+
+def should_omit_symbol(symbol, arch, api, llndk, apex):
+    """Returns True if the symbol should be omitted."""
+    no_llndk_no_apex = 'llndk' not in symbol.tags and 'apex' not in symbol.tags
+    keep = no_llndk_no_apex or \
+           ('llndk' in symbol.tags and llndk) or \
+           ('apex' in symbol.tags and apex)
+    if not keep:
+        return True
+    if not symbol_in_arch(symbol.tags, arch):
+        return True
+    if not symbol_in_api(symbol.tags, arch, api):
+        return True
+    return False
+
+
+def symbol_in_arch(tags, arch):
+    """Returns true if the symbol is present for the given architecture."""
+    has_arch_tags = False
+    for tag in tags:
+        if tag == arch:
+            return True
+        if tag in ALL_ARCHITECTURES:
+            has_arch_tags = True
+
+    # If there were no arch tags, the symbol is available for all
+    # architectures. If there were any arch tags, the symbol is only available
+    # for the tagged architectures.
+    return not has_arch_tags
+
+
+def symbol_in_api(tags, arch, api):
+    """Returns true if the symbol is present for the given API level."""
+    introduced_tag = None
+    arch_specific = False
+    for tag in tags:
+        # If there is an arch-specific tag, it should override the common one.
+        if tag.startswith('introduced=') and not arch_specific:
+            introduced_tag = tag
+        elif tag.startswith('introduced-' + arch + '='):
+            introduced_tag = tag
+            arch_specific = True
+        elif tag == 'future':
+            return api == FUTURE_API_LEVEL
+
+    if introduced_tag is None:
+        # We found no "introduced" tags, so the symbol has always been
+        # available.
+        return True
+
+    return api >= int(get_tag_value(introduced_tag))
+
+
+def symbol_versioned_in_api(tags, api):
+    """Returns true if the symbol should be versioned for the given API.
+
+    This models the `versioned=API` tag. This should be a very uncommonly
+    needed tag, and is really only needed to fix versioning mistakes that are
+    already out in the wild.
+
+    For example, some of libc's __aeabi_* functions were originally placed in
+    the private version, but that was incorrect. They are now in LIBC_N, but
+    when building against any version prior to N we need the symbol to be
+    unversioned (otherwise it won't resolve on M where it is private).
+    """
+    for tag in tags:
+        if tag.startswith('versioned='):
+            return api >= int(get_tag_value(tag))
+    # If there is no "versioned" tag, the tag has been versioned for as long as
+    # it was introduced.
+    return True
+
+
+class ParseError(RuntimeError):
+    """An error that occurred while parsing a symbol file."""
+    pass
+
+
+class MultiplyDefinedSymbolError(RuntimeError):
+    """A symbol name was multiply defined."""
+    def __init__(self, multiply_defined_symbols):
+        super(MultiplyDefinedSymbolError, self).__init__(
+            'Version script contains multiple definitions for: {}'.format(
+                ', '.join(multiply_defined_symbols)))
+        self.multiply_defined_symbols = multiply_defined_symbols
+
+
+class Version(object):
+    """A version block of a symbol file."""
+    def __init__(self, name, base, tags, symbols):
+        self.name = name
+        self.base = base
+        self.tags = tags
+        self.symbols = symbols
+
+    def __eq__(self, other):
+        if self.name != other.name:
+            return False
+        if self.base != other.base:
+            return False
+        if self.tags != other.tags:
+            return False
+        if self.symbols != other.symbols:
+            return False
+        return True
+
+
+class Symbol(object):
+    """A symbol definition from a symbol file."""
+    def __init__(self, name, tags):
+        self.name = name
+        self.tags = tags
+
+    def __eq__(self, other):
+        return self.name == other.name and set(self.tags) == set(other.tags)
+
+
+class SymbolFileParser(object):
+    """Parses NDK symbol files."""
+    def __init__(self, input_file, api_map, arch, api, llndk, apex):
+        self.input_file = input_file
+        self.api_map = api_map
+        self.arch = arch
+        self.api = api
+        self.llndk = llndk
+        self.apex = apex
+        self.current_line = None
+
+    def parse(self):
+        """Parses the symbol file and returns a list of Version objects."""
+        versions = []
+        while self.next_line() != '':
+            if '{' in self.current_line:
+                versions.append(self.parse_version())
+            else:
+                raise ParseError(
+                    'Unexpected contents at top level: ' + self.current_line)
+
+        self.check_no_duplicate_symbols(versions)
+        return versions
+
+    def check_no_duplicate_symbols(self, versions):
+        """Raises errors for multiply defined symbols.
+
+        This situation is the normal case when symbol versioning is actually
+        used, but this script doesn't currently handle that. The error message
+        will be a not necessarily obvious "error: redefition of 'foo'" from
+        stub.c, so it's better for us to catch this situation and raise a
+        better error.
+        """
+        symbol_names = set()
+        multiply_defined_symbols = set()
+        for version in versions:
+            if should_omit_version(version, self.arch, self.api, self.llndk, self.apex):
+                continue
+
+            for symbol in version.symbols:
+                if should_omit_symbol(symbol, self.arch, self.api, self.llndk, self.apex):
+                    continue
+
+                if symbol.name in symbol_names:
+                    multiply_defined_symbols.add(symbol.name)
+                symbol_names.add(symbol.name)
+        if multiply_defined_symbols:
+            raise MultiplyDefinedSymbolError(
+                sorted(list(multiply_defined_symbols)))
+
+    def parse_version(self):
+        """Parses a single version section and returns a Version object."""
+        name = self.current_line.split('{')[0].strip()
+        tags = get_tags(self.current_line)
+        tags = decode_api_level_tags(tags, self.api_map)
+        symbols = []
+        global_scope = True
+        cpp_symbols = False
+        while self.next_line() != '':
+            if '}' in self.current_line:
+                # Line is something like '} BASE; # tags'. Both base and tags
+                # are optional here.
+                base = self.current_line.partition('}')[2]
+                base = base.partition('#')[0].strip()
+                if not base.endswith(';'):
+                    raise ParseError(
+                        'Unterminated version/export "C++" block (expected ;).')
+                if cpp_symbols:
+                    cpp_symbols = False
+                else:
+                    base = base.rstrip(';').rstrip()
+                    if base == '':
+                        base = None
+                    return Version(name, base, tags, symbols)
+            elif 'extern "C++" {' in self.current_line:
+                cpp_symbols = True
+            elif not cpp_symbols and ':' in self.current_line:
+                visibility = self.current_line.split(':')[0].strip()
+                if visibility == 'local':
+                    global_scope = False
+                elif visibility == 'global':
+                    global_scope = True
+                else:
+                    raise ParseError('Unknown visiblity label: ' + visibility)
+            elif global_scope and not cpp_symbols:
+                symbols.append(self.parse_symbol())
+            else:
+                # We're in a hidden scope or in 'extern "C++"' block. Ignore
+                # everything.
+                pass
+        raise ParseError('Unexpected EOF in version block.')
+
+    def parse_symbol(self):
+        """Parses a single symbol line and returns a Symbol object."""
+        if ';' not in self.current_line:
+            raise ParseError(
+                'Expected ; to terminate symbol: ' + self.current_line)
+        if '*' in self.current_line:
+            raise ParseError(
+                'Wildcard global symbols are not permitted.')
+        # Line is now in the format "<symbol-name>; # tags"
+        name, _, _ = self.current_line.strip().partition(';')
+        tags = get_tags(self.current_line)
+        tags = decode_api_level_tags(tags, self.api_map)
+        return Symbol(name, tags)
+
+    def next_line(self):
+        """Returns the next non-empty non-comment line.
+
+        A return value of '' indicates EOF.
+        """
+        line = self.input_file.readline()
+        while line.strip() == '' or line.strip().startswith('#'):
+            line = self.input_file.readline()
+
+            # We want to skip empty lines, but '' indicates EOF.
+            if line == '':
+                break
+        self.current_line = line
+        return self.current_line
+
+
+class Generator(object):
+    """Output generator that writes stub source files and version scripts."""
+    def __init__(self, src_file, version_script, arch, api, llndk, apex):
+        self.src_file = src_file
+        self.version_script = version_script
+        self.arch = arch
+        self.api = api
+        self.llndk = llndk
+        self.apex = apex
+
+    def write(self, versions):
+        """Writes all symbol data to the output files."""
+        for version in versions:
+            self.write_version(version)
+
+    def write_version(self, version):
+        """Writes a single version block's data to the output files."""
+        if should_omit_version(version, self.arch, self.api, self.llndk, self.apex):
+            return
+
+        section_versioned = symbol_versioned_in_api(version.tags, self.api)
+        version_empty = True
+        pruned_symbols = []
+        for symbol in version.symbols:
+            if should_omit_symbol(symbol, self.arch, self.api, self.llndk, self.apex):
+                continue
+
+            if symbol_versioned_in_api(symbol.tags, self.api):
+                version_empty = False
+            pruned_symbols.append(symbol)
+
+        if len(pruned_symbols) > 0:
+            if not version_empty and section_versioned:
+                self.version_script.write(version.name + ' {\n')
+                self.version_script.write('    global:\n')
+            for symbol in pruned_symbols:
+                emit_version = symbol_versioned_in_api(symbol.tags, self.api)
+                if section_versioned and emit_version:
+                    self.version_script.write('        ' + symbol.name + ';\n')
+
+                weak = ''
+                if 'weak' in symbol.tags:
+                    weak = '__attribute__((weak)) '
+
+                if 'var' in symbol.tags:
+                    self.src_file.write('{}int {} = 0;\n'.format(
+                        weak, symbol.name))
+                else:
+                    self.src_file.write('{}void {}() {{}}\n'.format(
+                        weak, symbol.name))
+
+            if not version_empty and section_versioned:
+                base = '' if version.base is None else ' ' + version.base
+                self.version_script.write('}' + base + ';\n')
+
+
+def decode_api_level(api, api_map):
+    """Decodes the API level argument into the API level number.
+
+    For the average case, this just decodes the integer value from the string,
+    but for unreleased APIs we need to translate from the API codename (like
+    "O") to the future API level for that codename.
+    """
+    try:
+        return int(api)
+    except ValueError:
+        pass
+
+    if api == "current":
+        return FUTURE_API_LEVEL
+
+    return api_map[api]
+
+
+def parse_args():
+    """Parses and returns command line arguments."""
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument('-v', '--verbose', action='count', default=0)
+
+    parser.add_argument(
+        '--api', required=True, help='API level being targeted.')
+    parser.add_argument(
+        '--arch', choices=ALL_ARCHITECTURES, required=True,
+        help='Architecture being targeted.')
+    parser.add_argument(
+        '--llndk', action='store_true', help='Use the LLNDK variant.')
+    parser.add_argument(
+        '--apex', action='store_true', help='Use the APEX variant.')
+
+    parser.add_argument(
+        '--api-map', type=os.path.realpath, required=True,
+        help='Path to the API level map JSON file.')
+
+    parser.add_argument(
+        'symbol_file', type=os.path.realpath, help='Path to symbol file.')
+    parser.add_argument(
+        'stub_src', type=os.path.realpath,
+        help='Path to output stub source file.')
+    parser.add_argument(
+        'version_script', type=os.path.realpath,
+        help='Path to output version script.')
+
+    return parser.parse_args()
+
+
+def main():
+    """Program entry point."""
+    args = parse_args()
+
+    with open(args.api_map) as map_file:
+        api_map = json.load(map_file)
+    api = decode_api_level(args.api, api_map)
+
+    verbose_map = (logging.WARNING, logging.INFO, logging.DEBUG)
+    verbosity = args.verbose
+    if verbosity > 2:
+        verbosity = 2
+    logging.basicConfig(level=verbose_map[verbosity])
+
+    with open(args.symbol_file) as symbol_file:
+        try:
+            versions = SymbolFileParser(symbol_file, api_map, args.arch, api,
+                                        args.llndk, args.apex).parse()
+        except MultiplyDefinedSymbolError as ex:
+            sys.exit('{}: error: {}'.format(args.symbol_file, ex))
+
+    with open(args.stub_src, 'w') as src_file:
+        with open(args.version_script, 'w') as version_file:
+            generator = Generator(src_file, version_file, args.arch, api,
+                                  args.llndk, args.apex)
+            generator.write(versions)
+
+
+if __name__ == '__main__':
+    main()
diff --git a/cc/scriptlib/ndk_api_coverage_parser.py b/cc/scriptlib/ndk_api_coverage_parser.py
new file mode 100755
index 0000000..d74035b
--- /dev/null
+++ b/cc/scriptlib/ndk_api_coverage_parser.py
@@ -0,0 +1,134 @@
+#!/usr/bin/env 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.
+#
+"""Generates xml of NDK libraries used for API coverage analysis."""
+import argparse
+import json
+import os
+import sys
+
+from xml.etree.ElementTree import Element, SubElement, tostring
+from gen_stub_libs import ALL_ARCHITECTURES, FUTURE_API_LEVEL, MultiplyDefinedSymbolError, SymbolFileParser
+
+
+ROOT_ELEMENT_TAG = 'ndk-library'
+SYMBOL_ELEMENT_TAG = 'symbol'
+ARCHITECTURE_ATTRIBUTE_KEY = 'arch'
+DEPRECATED_ATTRIBUTE_KEY = 'is_deprecated'
+PLATFORM_ATTRIBUTE_KEY = 'is_platform'
+NAME_ATTRIBUTE_KEY = 'name'
+VARIABLE_TAG = 'var'
+EXPOSED_TARGET_TAGS = (
+    'vndk',
+    'apex',
+    'llndk',
+)
+API_LEVEL_TAG_PREFIXES = (
+    'introduced=',
+    'introduced-',
+)
+
+
+def parse_tags(tags):
+    """Parses tags and save needed tags in the created attributes.
+
+    Return attributes dictionary.
+    """
+    attributes = {}
+    arch = []
+    for tag in tags:
+        if tag.startswith(tuple(API_LEVEL_TAG_PREFIXES)):
+            key, _, value = tag.partition('=')
+            attributes.update({key: value})
+        elif tag in ALL_ARCHITECTURES:
+            arch.append(tag)
+        elif tag in EXPOSED_TARGET_TAGS:
+            attributes.update({tag: 'True'})
+    attributes.update({ARCHITECTURE_ATTRIBUTE_KEY: ','.join(arch)})
+    return attributes
+
+
+class XmlGenerator(object):
+    """Output generator that writes parsed symbol file to a xml file."""
+    def __init__(self, output_file):
+        self.output_file = output_file
+
+    def convertToXml(self, versions):
+        """Writes all symbol data to the output file."""
+        root = Element(ROOT_ELEMENT_TAG)
+        for version in versions:
+            if VARIABLE_TAG in version.tags:
+                continue
+            version_attributes = parse_tags(version.tags)
+            _, _, postfix = version.name.partition('_')
+            is_platform = postfix == 'PRIVATE' or postfix == 'PLATFORM'
+            is_deprecated = postfix == 'DEPRECATED'
+            version_attributes.update({PLATFORM_ATTRIBUTE_KEY: str(is_platform)})
+            version_attributes.update({DEPRECATED_ATTRIBUTE_KEY: str(is_deprecated)})
+            for symbol in version.symbols:
+                if VARIABLE_TAG in symbol.tags:
+                    continue
+                attributes = {NAME_ATTRIBUTE_KEY: symbol.name}
+                attributes.update(version_attributes)
+                # If same version tags already exist, it will be overwrite here.
+                attributes.update(parse_tags(symbol.tags))
+                SubElement(root, SYMBOL_ELEMENT_TAG, attributes)
+        return root
+
+    def write_xml_to_file(self, root):
+        """Write xml element root to output_file."""
+        parsed_data = tostring(root)
+        output_file = open(self.output_file, "wb")
+        output_file.write(parsed_data)
+
+    def write(self, versions):
+        root = self.convertToXml(versions)
+        self.write_xml_to_file(root)
+
+
+def parse_args():
+    """Parses and returns command line arguments."""
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument('symbol_file', type=os.path.realpath, help='Path to symbol file.')
+    parser.add_argument(
+        'output_file', type=os.path.realpath,
+        help='The output parsed api coverage file.')
+    parser.add_argument(
+        '--api-map', type=os.path.realpath, required=True,
+        help='Path to the API level map JSON file.')
+    return parser.parse_args()
+
+
+def main():
+    """Program entry point."""
+    args = parse_args()
+
+    with open(args.api_map) as map_file:
+        api_map = json.load(map_file)
+
+    with open(args.symbol_file) as symbol_file:
+        try:
+            versions = SymbolFileParser(symbol_file, api_map, "", FUTURE_API_LEVEL,
+                                        True, True).parse()
+        except MultiplyDefinedSymbolError as ex:
+            sys.exit('{}: error: {}'.format(args.symbol_file, ex))
+
+    generator = XmlGenerator(args.output_file)
+    generator.write(versions)
+
+if __name__ == '__main__':
+    main()
diff --git a/cc/scriptlib/test_gen_stub_libs.py b/cc/scriptlib/test_gen_stub_libs.py
new file mode 100755
index 0000000..0b45e71
--- /dev/null
+++ b/cc/scriptlib/test_gen_stub_libs.py
@@ -0,0 +1,807 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2016 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.
+#
+"""Tests for gen_stub_libs.py."""
+import io
+import textwrap
+import unittest
+
+import gen_stub_libs as gsl
+
+
+# pylint: disable=missing-docstring
+
+
+class DecodeApiLevelTest(unittest.TestCase):
+    def test_decode_api_level(self):
+        self.assertEqual(9, gsl.decode_api_level('9', {}))
+        self.assertEqual(9000, gsl.decode_api_level('O', {'O': 9000}))
+
+        with self.assertRaises(KeyError):
+            gsl.decode_api_level('O', {})
+
+
+class TagsTest(unittest.TestCase):
+    def test_get_tags_no_tags(self):
+        self.assertEqual([], gsl.get_tags(''))
+        self.assertEqual([], gsl.get_tags('foo bar baz'))
+
+    def test_get_tags(self):
+        self.assertEqual(['foo', 'bar'], gsl.get_tags('# foo bar'))
+        self.assertEqual(['bar', 'baz'], gsl.get_tags('foo # bar baz'))
+
+    def test_split_tag(self):
+        self.assertTupleEqual(('foo', 'bar'), gsl.split_tag('foo=bar'))
+        self.assertTupleEqual(('foo', 'bar=baz'), gsl.split_tag('foo=bar=baz'))
+        with self.assertRaises(ValueError):
+            gsl.split_tag('foo')
+
+    def test_get_tag_value(self):
+        self.assertEqual('bar', gsl.get_tag_value('foo=bar'))
+        self.assertEqual('bar=baz', gsl.get_tag_value('foo=bar=baz'))
+        with self.assertRaises(ValueError):
+            gsl.get_tag_value('foo')
+
+    def test_is_api_level_tag(self):
+        self.assertTrue(gsl.is_api_level_tag('introduced=24'))
+        self.assertTrue(gsl.is_api_level_tag('introduced-arm=24'))
+        self.assertTrue(gsl.is_api_level_tag('versioned=24'))
+
+        # Shouldn't try to process things that aren't a key/value tag.
+        self.assertFalse(gsl.is_api_level_tag('arm'))
+        self.assertFalse(gsl.is_api_level_tag('introduced'))
+        self.assertFalse(gsl.is_api_level_tag('versioned'))
+
+        # We don't support arch specific `versioned` tags.
+        self.assertFalse(gsl.is_api_level_tag('versioned-arm=24'))
+
+    def test_decode_api_level_tags(self):
+        api_map = {
+            'O': 9000,
+            'P': 9001,
+        }
+
+        tags = [
+            'introduced=9',
+            'introduced-arm=14',
+            'versioned=16',
+            'arm',
+            'introduced=O',
+            'introduced=P',
+        ]
+        expected_tags = [
+            'introduced=9',
+            'introduced-arm=14',
+            'versioned=16',
+            'arm',
+            'introduced=9000',
+            'introduced=9001',
+        ]
+        self.assertListEqual(
+            expected_tags, gsl.decode_api_level_tags(tags, api_map))
+
+        with self.assertRaises(gsl.ParseError):
+            gsl.decode_api_level_tags(['introduced=O'], {})
+
+
+class PrivateVersionTest(unittest.TestCase):
+    def test_version_is_private(self):
+        self.assertFalse(gsl.version_is_private('foo'))
+        self.assertFalse(gsl.version_is_private('PRIVATE'))
+        self.assertFalse(gsl.version_is_private('PLATFORM'))
+        self.assertFalse(gsl.version_is_private('foo_private'))
+        self.assertFalse(gsl.version_is_private('foo_platform'))
+        self.assertFalse(gsl.version_is_private('foo_PRIVATE_'))
+        self.assertFalse(gsl.version_is_private('foo_PLATFORM_'))
+
+        self.assertTrue(gsl.version_is_private('foo_PRIVATE'))
+        self.assertTrue(gsl.version_is_private('foo_PLATFORM'))
+
+
+class SymbolPresenceTest(unittest.TestCase):
+    def test_symbol_in_arch(self):
+        self.assertTrue(gsl.symbol_in_arch([], 'arm'))
+        self.assertTrue(gsl.symbol_in_arch(['arm'], 'arm'))
+
+        self.assertFalse(gsl.symbol_in_arch(['x86'], 'arm'))
+
+    def test_symbol_in_api(self):
+        self.assertTrue(gsl.symbol_in_api([], 'arm', 9))
+        self.assertTrue(gsl.symbol_in_api(['introduced=9'], 'arm', 9))
+        self.assertTrue(gsl.symbol_in_api(['introduced=9'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(['introduced-arm=9'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(['introduced-arm=9'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(['introduced-x86=14'], 'arm', 9))
+        self.assertTrue(gsl.symbol_in_api(
+            ['introduced-arm=9', 'introduced-x86=21'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(
+            ['introduced=9', 'introduced-x86=21'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(
+            ['introduced=21', 'introduced-arm=9'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(
+            ['future'], 'arm', gsl.FUTURE_API_LEVEL))
+
+        self.assertFalse(gsl.symbol_in_api(['introduced=14'], 'arm', 9))
+        self.assertFalse(gsl.symbol_in_api(['introduced-arm=14'], 'arm', 9))
+        self.assertFalse(gsl.symbol_in_api(['future'], 'arm', 9))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced=9', 'future'], 'arm', 14))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced-arm=9', 'future'], 'arm', 14))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced-arm=21', 'introduced-x86=9'], 'arm', 14))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced=9', 'introduced-arm=21'], 'arm', 14))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced=21', 'introduced-x86=9'], 'arm', 14))
+
+        # Interesting edge case: this symbol should be omitted from the
+        # library, but this call should still return true because none of the
+        # tags indiciate that it's not present in this API level.
+        self.assertTrue(gsl.symbol_in_api(['x86'], 'arm', 9))
+
+    def test_verioned_in_api(self):
+        self.assertTrue(gsl.symbol_versioned_in_api([], 9))
+        self.assertTrue(gsl.symbol_versioned_in_api(['versioned=9'], 9))
+        self.assertTrue(gsl.symbol_versioned_in_api(['versioned=9'], 14))
+
+        self.assertFalse(gsl.symbol_versioned_in_api(['versioned=14'], 9))
+
+
+class OmitVersionTest(unittest.TestCase):
+    def test_omit_private(self):
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, [], []), 'arm', 9, False, False))
+
+        self.assertTrue(
+            gsl.should_omit_version(
+                gsl.Version('foo_PRIVATE', None, [], []), 'arm', 9, False, False))
+        self.assertTrue(
+            gsl.should_omit_version(
+                gsl.Version('foo_PLATFORM', None, [], []), 'arm', 9, False, False))
+
+        self.assertTrue(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['platform-only'], []), 'arm', 9,
+                False, False))
+
+    def test_omit_llndk(self):
+        self.assertTrue(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['llndk'], []), 'arm', 9, False, False))
+
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, [], []), 'arm', 9, True, False))
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['llndk'], []), 'arm', 9, True, False))
+
+    def test_omit_apex(self):
+        self.assertTrue(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['apex'], []), 'arm', 9, False, False))
+
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, [], []), 'arm', 9, False, True))
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['apex'], []), 'arm', 9, False, True))
+
+    def test_omit_arch(self):
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, [], []), 'arm', 9, False, False))
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['arm'], []), 'arm', 9, False, False))
+
+        self.assertTrue(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['x86'], []), 'arm', 9, False, False))
+
+    def test_omit_api(self):
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, [], []), 'arm', 9, False, False))
+        self.assertFalse(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['introduced=9'], []), 'arm', 9,
+                False, False))
+
+        self.assertTrue(
+            gsl.should_omit_version(
+                gsl.Version('foo', None, ['introduced=14'], []), 'arm', 9,
+                False, False))
+
+
+class OmitSymbolTest(unittest.TestCase):
+    def test_omit_llndk(self):
+        self.assertTrue(
+            gsl.should_omit_symbol(
+                gsl.Symbol('foo', ['llndk']), 'arm', 9, False, False))
+
+        self.assertFalse(
+            gsl.should_omit_symbol(gsl.Symbol('foo', []), 'arm', 9, True, False))
+        self.assertFalse(
+            gsl.should_omit_symbol(
+                gsl.Symbol('foo', ['llndk']), 'arm', 9, True, False))
+
+    def test_omit_apex(self):
+        self.assertTrue(
+            gsl.should_omit_symbol(
+                gsl.Symbol('foo', ['apex']), 'arm', 9, False, False))
+
+        self.assertFalse(
+            gsl.should_omit_symbol(gsl.Symbol('foo', []), 'arm', 9, False, True))
+        self.assertFalse(
+            gsl.should_omit_symbol(
+                gsl.Symbol('foo', ['apex']), 'arm', 9, False, True))
+
+    def test_omit_arch(self):
+        self.assertFalse(
+            gsl.should_omit_symbol(gsl.Symbol('foo', []), 'arm', 9, False, False))
+        self.assertFalse(
+            gsl.should_omit_symbol(
+                gsl.Symbol('foo', ['arm']), 'arm', 9, False, False))
+
+        self.assertTrue(
+            gsl.should_omit_symbol(
+                gsl.Symbol('foo', ['x86']), 'arm', 9, False, False))
+
+    def test_omit_api(self):
+        self.assertFalse(
+            gsl.should_omit_symbol(gsl.Symbol('foo', []), 'arm', 9, False, False))
+        self.assertFalse(
+            gsl.should_omit_symbol(
+                gsl.Symbol('foo', ['introduced=9']), 'arm', 9, False, False))
+
+        self.assertTrue(
+            gsl.should_omit_symbol(
+                gsl.Symbol('foo', ['introduced=14']), 'arm', 9, False, False))
+
+
+class SymbolFileParseTest(unittest.TestCase):
+    def test_next_line(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            foo
+
+            bar
+            # baz
+            qux
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+        self.assertIsNone(parser.current_line)
+
+        self.assertEqual('foo', parser.next_line().strip())
+        self.assertEqual('foo', parser.current_line.strip())
+
+        self.assertEqual('bar', parser.next_line().strip())
+        self.assertEqual('bar', parser.current_line.strip())
+
+        self.assertEqual('qux', parser.next_line().strip())
+        self.assertEqual('qux', parser.current_line.strip())
+
+        self.assertEqual('', parser.next_line())
+        self.assertEqual('', parser.current_line)
+
+    def test_parse_version(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 { # foo bar
+                baz;
+                qux; # woodly doodly
+            };
+
+            VERSION_2 {
+            } VERSION_1; # asdf
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+
+        parser.next_line()
+        version = parser.parse_version()
+        self.assertEqual('VERSION_1', version.name)
+        self.assertIsNone(version.base)
+        self.assertEqual(['foo', 'bar'], version.tags)
+
+        expected_symbols = [
+            gsl.Symbol('baz', []),
+            gsl.Symbol('qux', ['woodly', 'doodly']),
+        ]
+        self.assertEqual(expected_symbols, version.symbols)
+
+        parser.next_line()
+        version = parser.parse_version()
+        self.assertEqual('VERSION_2', version.name)
+        self.assertEqual('VERSION_1', version.base)
+        self.assertEqual([], version.tags)
+
+    def test_parse_version_eof(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+        parser.next_line()
+        with self.assertRaises(gsl.ParseError):
+            parser.parse_version()
+
+    def test_unknown_scope_label(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                foo:
+            }
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+        parser.next_line()
+        with self.assertRaises(gsl.ParseError):
+            parser.parse_version()
+
+    def test_parse_symbol(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            foo;
+            bar; # baz qux
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+
+        parser.next_line()
+        symbol = parser.parse_symbol()
+        self.assertEqual('foo', symbol.name)
+        self.assertEqual([], symbol.tags)
+
+        parser.next_line()
+        symbol = parser.parse_symbol()
+        self.assertEqual('bar', symbol.name)
+        self.assertEqual(['baz', 'qux'], symbol.tags)
+
+    def test_wildcard_symbol_global(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                *;
+            };
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+        parser.next_line()
+        with self.assertRaises(gsl.ParseError):
+            parser.parse_version()
+
+    def test_wildcard_symbol_local(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                local:
+                    *;
+            };
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+        parser.next_line()
+        version = parser.parse_version()
+        self.assertEqual([], version.symbols)
+
+    def test_missing_semicolon(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                foo
+            };
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+        parser.next_line()
+        with self.assertRaises(gsl.ParseError):
+            parser.parse_version()
+
+    def test_parse_fails_invalid_input(self):
+        with self.assertRaises(gsl.ParseError):
+            input_file = io.StringIO('foo')
+            parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+            parser.parse()
+
+    def test_parse(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                local:
+                    hidden1;
+                global:
+                    foo;
+                    bar; # baz
+            };
+
+            VERSION_2 { # wasd
+                # Implicit global scope.
+                    woodly;
+                    doodly; # asdf
+                local:
+                    qwerty;
+            } VERSION_1;
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+        versions = parser.parse()
+
+        expected = [
+            gsl.Version('VERSION_1', None, [], [
+                gsl.Symbol('foo', []),
+                gsl.Symbol('bar', ['baz']),
+            ]),
+            gsl.Version('VERSION_2', 'VERSION_1', ['wasd'], [
+                gsl.Symbol('woodly', []),
+                gsl.Symbol('doodly', ['asdf']),
+            ]),
+        ]
+
+        self.assertEqual(expected, versions)
+
+    def test_parse_llndk_apex_symbol(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                foo;
+                bar; # llndk
+                baz; # llndk apex
+                qux; # apex
+            };
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, True)
+
+        parser.next_line()
+        version = parser.parse_version()
+        self.assertEqual('VERSION_1', version.name)
+        self.assertIsNone(version.base)
+
+        expected_symbols = [
+            gsl.Symbol('foo', []),
+            gsl.Symbol('bar', ['llndk']),
+            gsl.Symbol('baz', ['llndk', 'apex']),
+            gsl.Symbol('qux', ['apex']),
+        ]
+        self.assertEqual(expected_symbols, version.symbols)
+
+
+class GeneratorTest(unittest.TestCase):
+    def test_omit_version(self):
+        # Thorough testing of the cases involved here is handled by
+        # OmitVersionTest, PrivateVersionTest, and SymbolPresenceTest.
+        src_file = io.StringIO()
+        version_file = io.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9, False, False)
+
+        version = gsl.Version('VERSION_PRIVATE', None, [], [
+            gsl.Symbol('foo', []),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+        version = gsl.Version('VERSION', None, ['x86'], [
+            gsl.Symbol('foo', []),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+        version = gsl.Version('VERSION', None, ['introduced=14'], [
+            gsl.Symbol('foo', []),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+    def test_omit_symbol(self):
+        # Thorough testing of the cases involved here is handled by
+        # SymbolPresenceTest.
+        src_file = io.StringIO()
+        version_file = io.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9, False, False)
+
+        version = gsl.Version('VERSION_1', None, [], [
+            gsl.Symbol('foo', ['x86']),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+        version = gsl.Version('VERSION_1', None, [], [
+            gsl.Symbol('foo', ['introduced=14']),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+        version = gsl.Version('VERSION_1', None, [], [
+            gsl.Symbol('foo', ['llndk']),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+        version = gsl.Version('VERSION_1', None, [], [
+            gsl.Symbol('foo', ['apex']),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+    def test_write(self):
+        src_file = io.StringIO()
+        version_file = io.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9, False, False)
+
+        versions = [
+            gsl.Version('VERSION_1', None, [], [
+                gsl.Symbol('foo', []),
+                gsl.Symbol('bar', ['var']),
+                gsl.Symbol('woodly', ['weak']),
+                gsl.Symbol('doodly', ['weak', 'var']),
+            ]),
+            gsl.Version('VERSION_2', 'VERSION_1', [], [
+                gsl.Symbol('baz', []),
+            ]),
+            gsl.Version('VERSION_3', 'VERSION_1', [], [
+                gsl.Symbol('qux', ['versioned=14']),
+            ]),
+        ]
+
+        generator.write(versions)
+        expected_src = textwrap.dedent("""\
+            void foo() {}
+            int bar = 0;
+            __attribute__((weak)) void woodly() {}
+            __attribute__((weak)) int doodly = 0;
+            void baz() {}
+            void qux() {}
+        """)
+        self.assertEqual(expected_src, src_file.getvalue())
+
+        expected_version = textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo;
+                    bar;
+                    woodly;
+                    doodly;
+            };
+            VERSION_2 {
+                global:
+                    baz;
+            } VERSION_1;
+        """)
+        self.assertEqual(expected_version, version_file.getvalue())
+
+
+class IntegrationTest(unittest.TestCase):
+    def test_integration(self):
+        api_map = {
+            'O': 9000,
+            'P': 9001,
+        }
+
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo; # var
+                    bar; # x86
+                    fizz; # introduced=O
+                    buzz; # introduced=P
+                local:
+                    *;
+            };
+
+            VERSION_2 { # arm
+                baz; # introduced=9
+                qux; # versioned=14
+            } VERSION_1;
+
+            VERSION_3 { # introduced=14
+                woodly;
+                doodly; # var
+            } VERSION_2;
+
+            VERSION_4 { # versioned=9
+                wibble;
+                wizzes; # llndk
+                waggle; # apex
+            } VERSION_2;
+
+            VERSION_5 { # versioned=14
+                wobble;
+            } VERSION_4;
+        """))
+        parser = gsl.SymbolFileParser(input_file, api_map, 'arm', 9, False, False)
+        versions = parser.parse()
+
+        src_file = io.StringIO()
+        version_file = io.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9, False, False)
+        generator.write(versions)
+
+        expected_src = textwrap.dedent("""\
+            int foo = 0;
+            void baz() {}
+            void qux() {}
+            void wibble() {}
+            void wobble() {}
+        """)
+        self.assertEqual(expected_src, src_file.getvalue())
+
+        expected_version = textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo;
+            };
+            VERSION_2 {
+                global:
+                    baz;
+            } VERSION_1;
+            VERSION_4 {
+                global:
+                    wibble;
+            } VERSION_2;
+        """)
+        self.assertEqual(expected_version, version_file.getvalue())
+
+    def test_integration_future_api(self):
+        api_map = {
+            'O': 9000,
+            'P': 9001,
+            'Q': 9002,
+        }
+
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo; # introduced=O
+                    bar; # introduced=P
+                    baz; # introduced=Q
+                local:
+                    *;
+            };
+        """))
+        parser = gsl.SymbolFileParser(input_file, api_map, 'arm', 9001, False, False)
+        versions = parser.parse()
+
+        src_file = io.StringIO()
+        version_file = io.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9001, False, False)
+        generator.write(versions)
+
+        expected_src = textwrap.dedent("""\
+            void foo() {}
+            void bar() {}
+        """)
+        self.assertEqual(expected_src, src_file.getvalue())
+
+        expected_version = textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo;
+                    bar;
+            };
+        """)
+        self.assertEqual(expected_version, version_file.getvalue())
+
+    def test_multiple_definition(self):
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo;
+                    foo;
+                    bar;
+                    baz;
+                    qux; # arm
+                local:
+                    *;
+            };
+
+            VERSION_2 {
+                global:
+                    bar;
+                    qux; # arm64
+            } VERSION_1;
+
+            VERSION_PRIVATE {
+                global:
+                    baz;
+            } VERSION_2;
+
+        """))
+        parser = gsl.SymbolFileParser(input_file, {}, 'arm', 16, False, False)
+
+        with self.assertRaises(gsl.MultiplyDefinedSymbolError) as cm:
+            parser.parse()
+        self.assertEquals(['bar', 'foo'],
+                          cm.exception.multiply_defined_symbols)
+
+    def test_integration_with_apex(self):
+        api_map = {
+            'O': 9000,
+            'P': 9001,
+        }
+
+        input_file = io.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo; # var
+                    bar; # x86
+                    fizz; # introduced=O
+                    buzz; # introduced=P
+                local:
+                    *;
+            };
+
+            VERSION_2 { # arm
+                baz; # introduced=9
+                qux; # versioned=14
+            } VERSION_1;
+
+            VERSION_3 { # introduced=14
+                woodly;
+                doodly; # var
+            } VERSION_2;
+
+            VERSION_4 { # versioned=9
+                wibble;
+                wizzes; # llndk
+                waggle; # apex
+                bubble; # apex llndk
+                duddle; # llndk apex
+            } VERSION_2;
+
+            VERSION_5 { # versioned=14
+                wobble;
+            } VERSION_4;
+        """))
+        parser = gsl.SymbolFileParser(input_file, api_map, 'arm', 9, False, True)
+        versions = parser.parse()
+
+        src_file = io.StringIO()
+        version_file = io.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9, False, True)
+        generator.write(versions)
+
+        expected_src = textwrap.dedent("""\
+            int foo = 0;
+            void baz() {}
+            void qux() {}
+            void wibble() {}
+            void waggle() {}
+            void bubble() {}
+            void duddle() {}
+            void wobble() {}
+        """)
+        self.assertEqual(expected_src, src_file.getvalue())
+
+        expected_version = textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo;
+            };
+            VERSION_2 {
+                global:
+                    baz;
+            } VERSION_1;
+            VERSION_4 {
+                global:
+                    wibble;
+                    waggle;
+                    bubble;
+                    duddle;
+            } VERSION_2;
+        """)
+        self.assertEqual(expected_version, version_file.getvalue())
+
+def main():
+    suite = unittest.TestLoader().loadTestsFromName(__name__)
+    unittest.TextTestRunner(verbosity=3).run(suite)
+
+
+if __name__ == '__main__':
+    main()
diff --git a/cc/scriptlib/test_ndk_api_coverage_parser.py b/cc/scriptlib/test_ndk_api_coverage_parser.py
new file mode 100644
index 0000000..a3c9b70
--- /dev/null
+++ b/cc/scriptlib/test_ndk_api_coverage_parser.py
@@ -0,0 +1,66 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2016 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.
+#
+"""Tests for ndk_api_coverage_parser.py."""
+import io
+import textwrap
+import unittest
+
+from xml.etree.ElementTree import tostring
+from gen_stub_libs import FUTURE_API_LEVEL, SymbolFileParser
+import ndk_api_coverage_parser as nparser
+
+
+# pylint: disable=missing-docstring
+
+
+class ApiCoverageSymbolFileParserTest(unittest.TestCase):
+    def test_parse(self):
+        input_file = io.StringIO(textwrap.dedent(u"""\
+            LIBLOG { # introduced-arm64=24 introduced-x86=24 introduced-x86_64=24
+              global:
+                android_name_to_log_id; # apex llndk introduced=23
+                android_log_id_to_name; # llndk arm
+                __android_log_assert; # introduced-x86=23
+                __android_log_buf_print; # var
+                __android_log_buf_write;
+              local:
+                *;
+            };
+            
+            LIBLOG_PLATFORM {
+                android_fdtrack; # llndk
+                android_net; # introduced=23
+            };
+            
+            LIBLOG_FOO { # var
+                android_var;
+            };
+        """))
+        parser = SymbolFileParser(input_file, {}, "", FUTURE_API_LEVEL, True, True)
+        generator = nparser.XmlGenerator(io.StringIO())
+        result = tostring(generator.convertToXml(parser.parse())).decode()
+        expected = '<ndk-library><symbol apex="True" arch="" introduced="23" introduced-arm64="24" introduced-x86="24" introduced-x86_64="24" is_deprecated="False" is_platform="False" llndk="True" name="android_name_to_log_id" /><symbol arch="arm" introduced-arm64="24" introduced-x86="24" introduced-x86_64="24" is_deprecated="False" is_platform="False" llndk="True" name="android_log_id_to_name" /><symbol arch="" introduced-arm64="24" introduced-x86="23" introduced-x86_64="24" is_deprecated="False" is_platform="False" name="__android_log_assert" /><symbol arch="" introduced-arm64="24" introduced-x86="24" introduced-x86_64="24" is_deprecated="False" is_platform="False" name="__android_log_buf_write" /><symbol arch="" is_deprecated="False" is_platform="True" llndk="True" name="android_fdtrack" /><symbol arch="" introduced="23" is_deprecated="False" is_platform="True" name="android_net" /></ndk-library>'
+        self.assertEqual(expected, result)
+
+
+def main():
+    suite = unittest.TestLoader().loadTestsFromName(__name__)
+    unittest.TextTestRunner(verbosity=3).run(suite)
+
+
+if __name__ == '__main__':
+    main()