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+#!/usr/bin/env python3
+#
+# Copyright OpenEmbedded Contributors
+#
+# SPDX-License-Identifier: MIT
+#
+# This script is to be called by b4:
+# - through the b4.prep-perpatch-check-cmd with "prep-perpatch-check-cmd" as
+# first argument,
+# - through b4.send-auto-cc-cmd with "send-auto-cc-cmd" as first argument,
+# - through b4.send-auto-to-cmd with "send-auto-to-cmd" as first argument,
+#
+# When prep-perpatch-check-cmd is passsed:
+#
+# This checks that a patch makes changes to at most one project in the poky
+# combo repo (that is, out of yocto-docs, bitbake, openembedded-core combined
+# into poky and the poky-specific files).
+#
+# Printing something to stdout in this file will result in b4 prep --check fail
+# for the currently parsed patch.
+#
+# It checks that all patches in the series make changes to at most one project.
+#
+# When send-auto-cc-cmd is passed:
+#
+# This returns the list of Cc recipients for a patch.
+#
+# When send-auto-to-cmd is passed:
+#
+# This returns the list of To recipients for a patch.
+#
+# This script takes as stdin a patch.
+
+import pathlib
+import re
+import shutil
+import subprocess
+import sys
+
+cmd = sys.argv[1]
+
+patch = sys.stdin.readlines()
+
+# Subject field is used to identify the last patch as this script is called for
+# each patch. We edit the same file in a series by using the References field
+# unique identifier to check which projects are modified by earlier patches in
+# the series. To avoid cluttering the disk, the last patch in the list removes
+# that shared file.
+re_subject = re.compile(r'^Subject:.*\[.*PATCH.*\s(\d+)/\1')
+re_ref = re.compile(r'^References: <(.*)>$')
+
+subject = None
+ref = None
+
+if not shutil.which("lsdiff"):
+ print("lsdiff missing from host, please install patchutils")
+ sys.exit(-1)
+
+try:
+ one_patch_series = False
+ for line in patch:
+ subject = re_subject.match(line)
+ if subject:
+ # Handle [PATCH 1/1]
+ if subject.group(1) == 1:
+ one_patch_series = True
+ break
+ if re.match(r'^Subject: .*\[.*PATCH[^/]*\]', line):
+ # Single patch is named [PATCH] but if there are prefix, it could be
+ # [PATCH prefix], so handle everything that doesn't have a /
+ # character which is used as separator between current patch number
+ # and total patch number
+ one_patch_series = True
+ break
+
+ if cmd == "prep-perpatch-check-cmd" and not one_patch_series:
+ for line in patch:
+ ref = re_ref.match(line)
+ if ref:
+ break
+
+ if not ref:
+ print("Failed to find ref to cover letter (References:)...")
+ sys.exit(-2)
+
+ ref = ref.group(1)
+ series_check = pathlib.Path(f".tmp-{ref}")
+
+ patch = "".join(patch)
+
+ if cmd == "send-auto-cc-cmd":
+ # Patches to BitBake documentation should also go to yocto-docs mailing list
+ project_paths = {
+ "yocto-docs": ["bitbake/doc/*"],
+ }
+ else:
+ project_paths = {
+ "bitbake": ["bitbake/*"],
+ "yocto-docs": ["documentation/*"],
+ "poky": [
+ "meta-poky/*",
+ "meta-yocto-bsp/*",
+ "README.hardware.md",
+ "README.poky.md",
+ ],
+ }
+
+ # List of projects touched by this patch
+ projs = []
+
+ # Any file not matched by any path in project_paths means it is from
+ # OE-Core.
+ # When matching some path in project_paths, remove the matched files from
+ # that list.
+ files_left = subprocess.check_output(["lsdiff", "--strip-match=1", "--strip=1"],
+ input=patch, text=True)
+ files_left = set(files_left)
+
+ for proj, proj_paths in project_paths.items():
+ lsdiff_args = [f"--include={path}" for path in proj_paths]
+ files = subprocess.check_output(["lsdiff", "--strip-match=1", "--strip=1"] + lsdiff_args,
+ input=patch, text=True)
+ if len(files):
+ files_left = files_left - set(files)
+ projs.append(proj)
+ continue
+
+ # Handle patches made with --no-prefix
+ files = subprocess.check_output(["lsdiff"] + lsdiff_args,
+ input=patch, text=True)
+ if len(files):
+ files_left = files_left - set(files)
+ projs.append(proj)
+
+ # Catch-all for everything not poky-specific or in bitbake/yocto-docs
+ if len(files_left) and cmd != "send-auto-cc-cmd":
+ projs.append("openembedded-core")
+
+ if cmd == "prep-perpatch-check-cmd":
+ if len(projs) > 1:
+ print(f"Diff spans more than one project ({', '.join(sorted(projs))}), split into multiple commits...")
+ sys.exit(-3)
+
+ # No need to check other patches in the series as there aren't any
+ if one_patch_series:
+ sys.exit(0)
+
+ # This should be replaced once b4 supports prep-perseries-check-cmd (or something similar)
+
+ if series_check.exists():
+ # NOT race-free if b4 decides to parallelize prep-perpatch-check-cmd
+ series_projs = series_check.read_text().split('\n')
+ else:
+ series_projs = []
+
+ series_projs += projs
+ uniq_series_projs = set(series_projs)
+ # NOT race-free, if b4 decides to parallelize prep-perpatch-check-cmd
+ series_check.write_text('\n'.join(uniq_series_projs))
+
+ if len(uniq_series_projs) > 1:
+ print(f"Series spans more than one project ({', '.join(sorted(uniq_series_projs))}), split into multiple series...")
+ sys.exit(-4)
+ else: # send-auto-cc-cmd / send-auto-to-cmd
+ ml_projs = {
+ "bitbake": "bitbake-devel@lists.openembedded.org",
+ "yocto-docs": "docs@lists.yoctoproject.org",
+ "poky": "poky@lists.yoctoproject.org",
+ "openembedded-core": "openembedded-core@lists.openembedded.org",
+ }
+
+ print("\n".join([ml_projs[ml] for ml in projs]))
+
+ sys.exit(0)
+finally:
+ # Last patch in the series, cleanup tmp file
+ if subject and ref and series_check.exists():
+ series_check.unlink()