def _merge_new_units(self, target_path, corpus_dir, new_corpus_dir,
fuzz_corpus_dirs, arguments, stat_overrides):
"""Merge new units."""
# Make a decision on whether merge step is needed at all. If there are no
# new units added by libFuzzer run, then no need to do merge at all.
new_units_added = shell.get_directory_file_count(new_corpus_dir)
if not new_units_added:
stat_overrides['new_units_added'] = 0
logs.log(
'Skipped corpus merge since no new units added by fuzzing.')
return
# If this times out, it's possible that we will miss some units. However, if
# we're taking >10 minutes to load/merge the corpus something is going very
# wrong and we probably don't want to make things worse by adding units
# anyway.
merge_corpus = self._create_temp_corpus_dir('merge-corpus')
merge_dirs = [new_corpus_dir]
merge_dirs.extend(fuzz_corpus_dirs)
# Merge the new units with the initial corpus.
if corpus_dir not in merge_dirs:
merge_dirs.append(corpus_dir)
old_corpus_len = shell.get_directory_file_count(corpus_dir)
new_units_added = 0
try:
result = self.minimize_corpus(
target_path=target_path,
arguments=arguments,
input_dirs=merge_dirs,
output_dir=merge_corpus,
reproducers_dir=None,
max_time=engine_common.get_merge_timeout(
launcher.DEFAULT_MERGE_TIMEOUT))
launcher.move_mergeable_units(merge_corpus, corpus_dir)
new_corpus_len = shell.get_directory_file_count(corpus_dir)
new_units_added = new_corpus_len - old_corpus_len
if result.logs:
stat_overrides.update(
stats.parse_stats_from_merge_log(result.logs.splitlines()))
except MergeError:
logs.log_error('Merge failed.')
stat_overrides['new_units_added'] = new_units_added
logs.log('Stats calculated', stats=stat_overrides)
# Record the stats to make them easily searchable in stackdriver.
if new_units_added:
logs.log('New units added to corpus: %d.' % new_units_added)
else:
logs.log('No new units found.')
def move_mergeable_units(self):
"""Helper function for move_mergeable_units."""
launcher.move_mergeable_units(self.MERGE_DIRECTORY,
self.CORPUS_DIRECTORY)