Release: Add a script that generates a changelog for engineering build

Signed-off-by: Anton Kolesov <[email protected]>

Author: anthony-kolesov

generate-changelog.py

@@ -0,0 +1,77 @@
+#!/usr/bin/env python3
+
+import argparse
+import os.path
+import subprocess
+import sys
+import re
+
+parser = argparse.ArgumentParser(
+        description="Generate a changelog for an engineering build or RC of ARC GNU Toolchain.")
+parser.add_argument("--src-dir", required=True,
+        help="Root of toolchain source directories.")
+parser.add_argument("--tag", required=True,
+        help="Git tag of a new build.")
+parser.add_argument("--max-commits", default=50, type=int,
+        help="Maximum number of commits printed for one project.")
+
+args = parser.parse_args()
+
+repos = ["binutils", "gcc", "gdb", "newlib", "toolchain", "uClibc" ]
+
+new_tag = args.tag
+
+# Build an old tag. RC and eng build has different formats.
+build_num_m = re.search("\D*(\d+)$", new_tag)
+build_num = int(build_num_m.group(1))
+old_tag = new_tag[0:build_num_m.start(1)]
+if old_tag.endswith("-eng"):
+    old_tag += "{0:03}".format(build_num - 1)
+else:
+    old_tag += str(build_num - 1)
+
+git="git"
+
+def git_command(*args):
+    a = [git, git_dir]
+    a.extend(args)
+    return subprocess.check_output(a, universal_newlines=True)
+
+for repo in repos:
+    git_dir = "--git-dir=" + os.path.join(args.src_dir, repo, ".git")
+    # For GDB tag is different.
+    new_tag_effective = new_tag if repo != "gdb" else new_tag + "-gdb"
+    old_tag_effective = old_tag if repo != "gdb" else old_tag + "-gdb"
+
+    # First get commit ids. Use ^{} to get an ID of an actual commit, not an ID of a tag.
+    new_commit_id = git_command("rev-parse", new_tag_effective + "^{}")
+    old_commit_id = git_command("rev-parse", old_tag_effective + "^{}")
+
+    # Same? Nothing to do.
+    if old_commit_id == new_commit_id:
+        continue
+
+    print()
+    print(repo)
+    # Underline the header.
+    print('-' * max(len(repo), 7))
+
+    # Find the common base commit.
+    merge_base_id = git_command("merge-base", new_tag_effective, old_tag_effective)
+
+    # If it is the same as "old" then history is linear, no rebases, just use
+    # normal `git log --oneline`.
+    if merge_base_id == old_commit_id:
+        log_cmd = ["log", "--oneline", "{0}..{1}".format(old_tag_effective, new_tag_effective)]
+    else:
+        log_cmd = ["show-branch", old_tag_effective, new_tag_effective]
+
+    out = git_command(*log_cmd).splitlines()
+
+    if len(out) < args.max_commits:
+        print("\n".join(out))
+    else:
+        print("!!!Output is too long and has been truncated!!!")
+        print("\n".join(out[0:args.max_commits]))
+
+# vim: expandtab