Add CBMC-running GitHub Action

This commit adds a GitHub Action that runs the CBMC proofs in this
repository upon pushes and pull requests

.github/workflows/ci.yml

@@ -178,3 +178,12 @@ jobs:
         run: |
           git-secrets --register-aws
           git-secrets --scan
+  proof_ci:
+    runs-on: cbmc_ubuntu-latest_16-core
+    steps:
+      - name: Set up CBMC runner
+        uses: karkhaz/CI-CD-Github-Actions/set_up_cbmc_runner@kk-add-github-action
+      - name: Run CBMC
+        uses: karkhaz/CI-CD-Github-Actions/run_cbmc@kk-add-github-action
+        with:
+          proofs_dir: test/cbmc/proofs

test/cbmc/proofs/lib

@@ -0,0 +1,143 @@
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: MIT-0
+
+import argparse
+import json
+import logging
+import os
+import sys
+
+
+DESCRIPTION = """Print 2 tables in GitHub-flavored Markdown that summarize
+an execution of CBMC proofs."""
+
+
+def get_args():
+    """Parse arguments for summarize script."""
+    parser = argparse.ArgumentParser(description=DESCRIPTION)
+    for arg in [{
+            "flags": ["--run-file"],
+            "help": "path to the Litani run.json file",
+            "required": True,
+    }]:
+        flags = arg.pop("flags")
+        parser.add_argument(*flags, **arg)
+    return parser.parse_args()
+
+
+def _get_max_length_per_column_list(data):
+    ret = [len(item) + 1 for item in data[0]]
+    for row in data[1:]:
+        for idx, item in enumerate(row):
+            ret[idx] = max(ret[idx], len(item) + 1)
+    return ret
+
+
+def _get_table_header_separator(max_length_per_column_list):
+    line_sep = ""
+    for max_length_of_word_in_col in max_length_per_column_list:
+        line_sep += "|" + "-" * (max_length_of_word_in_col + 1)
+    line_sep += "|\n"
+    return line_sep
+
+
+def _get_entries(max_length_per_column_list, row_data):
+    entries = []
+    for row in row_data:
+        entry = ""
+        for idx, word in enumerate(row):
+            max_length_of_word_in_col = max_length_per_column_list[idx]
+            space_formatted_word = (max_length_of_word_in_col - len(word)) * " "
+            entry += "| " + word + space_formatted_word
+        entry += "|\n"
+        entries.append(entry)
+    return entries
+
+
+def _get_rendered_table(data):
+    table = []
+    max_length_per_column_list = _get_max_length_per_column_list(data)
+    entries = _get_entries(max_length_per_column_list, data)
+    for idx, entry in enumerate(entries):
+        if idx == 1:
+            line_sep = _get_table_header_separator(max_length_per_column_list)
+            table.append(line_sep)
+        table.append(entry)
+    table.append("\n")
+    return "".join(table)
+
+
+def _get_status_and_proof_summaries(run_dict):
+    """Parse a dict representing a Litani run and create lists summarizing the
+    proof results.
+
+    Parameters
+    ----------
+    run_dict
+        A dictionary representing a Litani run.
+
+
+    Returns
+    -------
+    A list of 2 lists.
+    The first sub-list maps a status to the number of proofs with that status.
+    The second sub-list maps each proof to its status.
+    """
+    count_statuses = {}
+    proofs = [["Proof", "Status"]]
+    for proof_pipeline in run_dict["pipelines"]:
+        status_pretty_name = proof_pipeline["status"].title().replace("_", " ")
+        try:
+            count_statuses[status_pretty_name] += 1
+        except KeyError:
+            count_statuses[status_pretty_name] = 1
+        if proof_pipeline["name"] == "print_tool_versions":
+            continue
+        proofs.append([proof_pipeline["name"], status_pretty_name])
+    statuses = [["Status", "Count"]]
+    for status, count in count_statuses.items():
+        statuses.append([status, str(count)])
+    return [statuses, proofs]
+
+
+def print_proof_results(out_file):
+    """
+    Print 2 strings that summarize the proof results.
+    When printing, each string will render as a GitHub flavored Markdown table.
+    """
+    output = "## Summary of CBMC proof results\n\n"
+    with open(out_file, encoding='utf-8') as run_json:
+        run_dict = json.load(run_json)
+    status_table, proof_table = _get_status_and_proof_summaries(run_dict)
+    for summary in (status_table, proof_table):
+        output += _get_rendered_table(summary)
+
+    print(output)
+    sys.stdout.flush()
+
+    github_summary_file = os.getenv("GITHUB_STEP_SUMMARY")
+    if github_summary_file:
+        with open(github_summary_file, "a") as handle:
+            print(output, file=handle)
+            handle.flush()
+    else:
+        logging.warning(
+            "$GITHUB_STEP_SUMMARY not set, not writing summary file")
+
+    msg = (
+        "Click the 'Summary' button to view a Markdown table "
+        "summarizing all proof results")
+    if run_dict["status"] != "success":
+        logging.error("Not all proofs passed.")
+        logging.error(msg)
+        sys.exit(1)
+    logging.info(msg)
+
+
+if __name__ == '__main__':
+    args = get_args()
+    logging.basicConfig(format="%(levelname)s: %(message)s")
+    try:
+        print_proof_results(args.run_file)
+    except Exception as ex: # pylint: disable=broad-except
+        logging.critical("Could not print results. Exception: %s", str(ex))