1#!/bin/sh
2# From Gerrit Code Review 2.13.5-2617-gba50ae91fd
3#
4# Part of Gerrit Code Review (https://www.gerritcodereview.com/)
5#
6# Copyright (C) 2009 The Android Open Source Project
7#
8# Licensed under the Apache License, Version 2.0 (the "License");
9# you may not use this file except in compliance with the License.
10# You may obtain a copy of the License at
11#
12# http://www.apache.org/licenses/LICENSE-2.0
13#
14# Unless required by applicable law or agreed to in writing, software
15# distributed under the License is distributed on an "AS IS" BASIS,
16# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17# See the License for the specific language governing permissions and
18# limitations under the License.
19#
20
21unset GREP_OPTIONS
22
23CHANGE_ID_AFTER="Bug|Depends-On|Issue|Test|Feature|Fixes|Fixed"
24MSG="$1"
25
26# Check for, and add if missing, a unique Change-Id
27#
28add_ChangeId() {
29	clean_message=`sed -e '
30		/^diff --git .*/{
31			s///
32			q
33		}
34		/^Signed-off-by:/d
35		/^#/d
36	' "$MSG" | git stripspace`
37	if test -z "$clean_message"
38	then
39		return
40	fi
41
42	# Do not add Change-Id to temp commits
43	if echo "$clean_message" | head -1 | grep -q '^\(fixup\|squash\)!'
44	then
45		return
46	fi
47
48	if test "false" = "`git config --bool --get gerrit.createChangeId`"
49	then
50		return
51	fi
52
53	# Does Change-Id: already exist? if so, exit (no change).
54	if grep -i '^Change-Id:' "$MSG" >/dev/null
55	then
56		return
57	fi
58
59	id=`_gen_ChangeId`
60	T="$MSG.tmp.$$"
61	AWK=awk
62	if [ -x /usr/xpg4/bin/awk ]; then
63		# Solaris AWK is just too broken
64		AWK=/usr/xpg4/bin/awk
65	fi
66
67	# Get core.commentChar from git config or use default symbol
68	commentChar=`git config --get core.commentChar`
69	commentChar=${commentChar:-#}
70
71	# How this works:
72	# - parse the commit message as (textLine+ blankLine*)*
73	# - assume textLine+ to be a footer until proven otherwise
74	# - exception: the first block is not footer (as it is the title)
75	# - read textLine+ into a variable
76	# - then count blankLines
77	# - once the next textLine appears, print textLine+ blankLine* as these
78	#   aren't footer
79	# - in END, the last textLine+ block is available for footer parsing
80	$AWK '
81	BEGIN {
82		# while we start with the assumption that textLine+
83		# is a footer, the first block is not.
84		isFooter = 0
85		footerComment = 0
86		blankLines = 0
87	}
88
89	# Skip lines starting with commentChar without any spaces before it.
90	/^'"$commentChar"'/ { next }
91
92	# Skip the line starting with the diff command and everything after it,
93	# up to the end of the file, assuming it is only patch data.
94	# If more than one line before the diff was empty, strip all but one.
95	/^diff --git / {
96		blankLines = 0
97		while (getline) { }
98		next
99	}
100
101	# Count blank lines outside footer comments
102	/^$/ && (footerComment == 0) {
103		blankLines++
104		next
105	}
106
107	# Catch footer comment
108	/^\[[a-zA-Z0-9-]+:/ && (isFooter == 1) {
109		footerComment = 1
110	}
111
112	/]$/ && (footerComment == 1) {
113		footerComment = 2
114	}
115
116	# We have a non-blank line after blank lines. Handle this.
117	(blankLines > 0) {
118		print lines
119		for (i = 0; i < blankLines; i++) {
120			print ""
121		}
122
123		lines = ""
124		blankLines = 0
125		isFooter = 1
126		footerComment = 0
127	}
128
129	# Detect that the current block is not the footer
130	(footerComment == 0) && (!/^\[?[a-zA-Z0-9-]+:/ || /^[a-zA-Z0-9-]+:\/\//) {
131		isFooter = 0
132	}
133
134	{
135		# We need this information about the current last comment line
136		if (footerComment == 2) {
137			footerComment = 0
138		}
139		if (lines != "") {
140			lines = lines "\n";
141		}
142		lines = lines $0
143	}
144
145	# Footer handling:
146	# If the last block is considered a footer, splice in the Change-Id at the
147	# right place.
148	# Look for the right place to inject Change-Id by considering
149	# CHANGE_ID_AFTER. Keys listed in it (case insensitive) come first,
150	# then Change-Id, then everything else (eg. Signed-off-by:).
151	#
152	# Otherwise just print the last block, a new line and the Change-Id as a
153	# block of its own.
154	END {
155		unprinted = 1
156		if (isFooter == 0) {
157			print lines "\n"
158			lines = ""
159		}
160		changeIdAfter = "^(" tolower("'"$CHANGE_ID_AFTER"'") "):"
161		numlines = split(lines, footer, "\n")
162		for (line = 1; line <= numlines; line++) {
163			if (unprinted && match(tolower(footer[line]), changeIdAfter) != 1) {
164				unprinted = 0
165				print "Change-Id: I'"$id"'"
166			}
167			print footer[line]
168		}
169		if (unprinted) {
170			print "Change-Id: I'"$id"'"
171		}
172	}' "$MSG" > "$T" && mv "$T" "$MSG" || rm -f "$T"
173}
174_gen_ChangeIdInput() {
175	echo "tree `git write-tree`"
176	if parent=`git rev-parse "HEAD^0" 2>/dev/null`
177	then
178		echo "parent $parent"
179	fi
180	echo "author `git var GIT_AUTHOR_IDENT`"
181	echo "committer `git var GIT_COMMITTER_IDENT`"
182	echo
183	printf '%s' "$clean_message"
184}
185_gen_ChangeId() {
186	_gen_ChangeIdInput |
187	git hash-object -t commit --stdin
188}
189
190
191add_ChangeId
192