[infra] Fixing bisection to work with more OSS-Fuzz projects (#3152)

* Max comments

* Added bisection tests

* Added test cases

* Docker run command added to build_specific commit

* Infer main repo uses docker image rather than docker file

* Added mores tests for repo infer

* With verbosity

* Formatting

* Bisection fixed

* Formatting updates

* Oliver small comments.

* Script infer main repo

* Detect repo and test module finished

* Detect main repo from script

* Regex searching

* Regex searching

* Max comments + bisector test script

* Oliver comments

* Max's comments

* String concat update

* Jonathan comments

1 files changed, 126 insertions, 0 deletions

diff --git a/infra/base-images/base-builder/detect_repo.py b/infra/base-images/base-builder/detect_repo.py
new file mode 100644
index 000000000..d7974ca5e
--- /dev/null
+++ b/infra/base-images/base-builder/detect_repo.py
@@ -0,0 +1,126 @@
+# Copyright 2019 Google LLC
+#
+# 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.
+"""Module to get the the name of a git repo containing a specific commit
+inside of an OSS-Fuzz project.
+
+Example Usage:
+
+  python detect_repo.py --src_dir /src --example_commit b534f03eecd8a109db2b085ab24d419b6486de97
+
+Prints the location of the git remote repo as well as the repos name seperated by a space.
+
+  https://github.com/VirusTotal/yara.git yara
+
+"""
+import argparse
+import os
+import subprocess
+
+
+def main():
+  """Function to get a git repos information based on its commit."""
+  parser = argparse.ArgumentParser(
+      description='Finds a specific git repo in an oss-fuzz projects docker file.'
+  )
+  parser.add_argument(
+      '--src_dir',
+      help='The location of the oss-fuzz projects source directory',
+      required=True)
+  parser.add_argument(
+      '--example_commit',
+      help='A commit SHA refrencing the projects main repo',
+      required=True)
+  args = parser.parse_args()
+  for single_dir in os.listdir(args.src_dir):
+    full_path = os.path.join(args.src_dir, single_dir)
+    if not os.path.isdir(full_path):
+      continue
+    if check_for_commit(
+        os.path.join(args.src_dir, full_path), args.example_commit):
+      print('Detected repo: %s %s' % (get_repo(full_path), single_dir.rstrip()))
+      return
+  print('No git repos with specific commit: %s found in %s' %
+        (args.example_commit, args.src_dir))
+
+
+def get_repo(repo_path):
+  """Gets a git repo link from a specific directory in a docker image.
+
+  Args:
+    repo_path: The directory on the image where the git repo exists.
+
+  Returns:
+    The repo location or None
+  """
+  output, return_code = execute(
+      ['git', 'config', '--get', 'remote.origin.url'],
+      location=repo_path,
+      check_result=True)
+  if return_code == 0 and output:
+    return output.rstrip()
+  return None
+
+
+def check_for_commit(repo_path, commit):
+  """Checks a directory for a specific commit.
+
+  Args:
+    repo_path: The name of the directory to test for the commit
+    commit: The commit SHA to check for
+
+  Returns:
+    True if directory contains that commit
+  """
+
+  # Check if valid git repo.
+  if not os.path.exists(os.path.join(repo_path, '.git')):
+    return False
+
+  # Check if history fetch is needed.
+  if os.path.exists(os.path.join(repo_path, '.git', 'shallow')):
+    execute(['git', 'fetch', '--unshallow'], location=repo_path)
+
+  # Check if commit is in history.
+  _, return_code = execute(['git', 'cat-file', '-e', commit],
+                               location=repo_path)
+  return return_code == 0
+
+
+def execute(command, location, check_result=False):
+  """Runs a shell command in the specified directory location.
+
+  Args:
+    command: The command as a list to be run
+    location: The directory the command is run in
+    check_result: Should an exception be thrown on failed command
+
+  Returns:
+    The stdout of the command, the error code
+
+  Raises:
+    RuntimeError: running a command resulted in an error
+  """
+  process = subprocess.Popen(command, stdout=subprocess.PIPE, cwd=location)
+  output, err = process.communicate()
+  if check_result and (process.returncode or err):
+    raise RuntimeError(
+        'Error: %s\n running command: %s\n return code: %s\n out %s\n' %
+        (err, command, process.returncode, output))
+  if output is not None:
+    output = output.decode('ascii')
+  return output, process.returncode
+
+
+if __name__ == '__main__':
+  main()