git hooks: update commit-msg to Gerrit 2.16.15

This mainly replaces the whole AWK code with the git helper
"interpret-trailers", which was added in git v2.2 end of 2014.

It also moves the argument checks from the original Gerrit hook
to the front of our tests to verify the script arguments.

Change-Id: I38c831bf7c9d399419a598d6966e48166d31ea6f
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/87369
Tested-by: Jenkins
Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>

1 files changed, 39 insertions, 165 deletions

diff --git a/.git-hooks/commit-msg b/.git-hooks/commit-msg
index 027c37510ff6..eebca62cb6f7 100755
--- a/.git-hooks/commit-msg
+++ b/.git-hooks/commit-msg
@@ -1,6 +1,5 @@
 #!/bin/sh
 #
-# An example hook script to check the commit log message.
 # Called by git-commit with one argument, the name of the file
 # that has the commit message.  The hook should exit with non-zero
 # status after issuing an appropriate message if it wants to stop the
@@ -8,14 +7,17 @@
 #
 # To enable this hook, make this file executable.
 
-# Uncomment the below to add a Signed-off-by line to the message.
-# SOB=$(git var GIT_AUTHOR_IDENT | sed -n 's/^\(.*>\).*$/Signed-off-by: \1/p')
-# grep -qs "^$SOB" "$1" || echo "$SOB" >> "$1"
+# avoid [[ which is not POSIX sh.
 
-# This example catches duplicate Signed-off-by lines.
+if test "$#" != 1 ; then
+    echo "$0 requires an argument."
+    exit 1
+fi
 
-base_dir=$(dirname $0)
-MSG="$1"
+if test ! -f "$1" ; then
+    echo "file does not exist: $1"
+    exit 1
+fi
 
 abort() {
     cp $1 $1.save
@@ -30,7 +32,7 @@ EOF
 
 test "" = "$(grep '^Signed-off-by: ' "$1" |
          sort | uniq -c | sed -e '/^[         ]*1[         ]/d')" || {
-        abort "$1" "Duplicate Signed-off-by lines."
+    abort "$1" "Duplicate Signed-off-by lines."
 }
 
 # Check that the first line exists, and is not an asterisk
@@ -74,11 +76,9 @@ if [ -n "`grep '^#[^[:blank:]]' $1`" ] ; then
     abort "$1" "Possible accidental comment in the commit message (leading # without space)."
 fi
 
-
-#------------------ copied gerrit commit-msg hook to handle ChangeId -->
-# From Gerrit Code Review 2.3
+# From Gerrit Code Review 2.16.15
 #
-# Part of Gerrit Code Review (http://code.google.com/p/gerrit/)
+# Part of Gerrit Code Review (https://www.gerritcodereview.com/)
 #
 # Copyright (C) 2009 The Android Open Source Project
 #
@@ -93,169 +93,43 @@ fi
 # 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.
-#
-
-CHANGE_ID_AFTER="Bug|Issue"
-
-# Check for, and add if missing, a unique Change-Id
-#
-add_ChangeId() {
-        clean_message=`sed -e '
-                /^diff --git .*/{
-                        s///
-                        q
-                }
-                /^Signed-off-by:/d
-                /^#/d
-        ' "$MSG" | git stripspace`
-        if test -z "$clean_message"
-        then
-                return
-        fi
-
-        if test "false" = "`git config --bool --get gerrit.createChangeId`"
-        then
-                return
-        fi
-
-        # Does Change-Id: already exist? if so, exit (no change).
-        if grep -i '^Change-Id:' "$MSG" >/dev/null
-        then
-                return
-        fi
-
-        id=`_gen_ChangeId`
-        T="$MSG.tmp.$$"
-        AWK=awk
-        if [ -x /usr/xpg4/bin/awk ]; then
-                # Solaris AWK is just too broken
-                AWK=/usr/xpg4/bin/awk
-        fi
-
-        # How this works:
-        # - parse the commit message as (textLine+ blankLine*)*
-        # - assume textLine+ to be a footer until proven otherwise
-        # - exception: the first block is not footer (as it is the title)
-        # - read textLine+ into a variable
-        # - then count blankLines
-        # - once the next textLine appears, print textLine+ blankLine* as these
-        #   aren't footer
-        # - in END, the last textLine+ block is available for footer parsing
-        $AWK '
-        BEGIN {
-                # while we start with the assumption that textLine+
-                # is a footer, the first block is not.
-                isFooter = 0
-                footerComment = 0
-                blankLines = 0
-        }
-
-        # Skip lines starting with "#" without any spaces before it.
-        /^#/ { next }
 
-        # Skip the line starting with the diff command and everything after it,
-        # up to the end of the file, assuming it is only patch data.
-        # If more than one line before the diff was empty, strip all but one.
-        /^diff --git / {
-                blankLines = 0
-                while (getline) { }
-                next
-        }
-
-        # Count blank lines outside footer comments
-        /^$/ && (footerComment == 0) {
-                blankLines++
-                next
-        }
-
-        # Catch footer comment
-        /^\[[a-zA-Z0-9-]+:/ && (isFooter == 1) {
-                footerComment = 1
-        }
-
-        /]$/ && (footerComment == 1) {
-                footerComment = 2
-        }
+# Do not create a change id if requested
+if test "false" = "`git config --bool --get gerrit.createChangeId`" ; then
+    exit 0
+fi
 
-        # We have a non-blank line after blank lines. Handle this.
-        (blankLines > 0) {
-                print lines
-                for (i = 0; i < blankLines; i++) {
-                        print ""
-                }
+# $RANDOM will be undefined if not using bash, so don't use set -u
+random=$( (whoami ; hostname ; date; cat $1 ; echo $RANDOM) | git hash-object --stdin)
+dest="$1.tmp.${random}"
 
-                lines = ""
-                blankLines = 0
-                isFooter = 1
-                footerComment = 0
-        }
+trap 'rm -f "${dest}"' EXIT
 
-        # Detect that the current block is not the footer
-        (footerComment == 0) && (!/^\[?[a-zA-Z0-9-]+:/ || /^[a-zA-Z0-9-]+:\/\//) {
-                isFooter = 0
-        }
+if ! git stripspace --strip-comments < "$1" > "${dest}" ; then
+    echo "cannot strip comments from $1"
+    exit 1
+fi
 
-        {
-                # We need this information about the current last comment line
-                if (footerComment == 2) {
-                        footerComment = 0
-                }
-                if (lines != "") {
-                        lines = lines "\n";
-                }
-                lines = lines $0
-        }
+if test ! -s "${dest}" ; then
+    echo "file is empty: $1"
+    exit 1
+fi
 
-        # Footer handling:
-        # If the last block is considered a footer, splice in the Change-Id at the
-        # right place.
-        # Look for the right place to inject Change-Id by considering
-        # CHANGE_ID_AFTER. Keys listed in it (case insensitive) come first,
-        # then Change-Id, then everything else (eg. Signed-off-by:).
-        #
-        # Otherwise just print the last block, a new line and the Change-Id as a
-        # block of its own.
-        END {
-                unprinted = 1
-                if (isFooter == 0) {
-                        print lines "\n"
-                        lines = ""
-                }
-                changeIdAfter = "^(" tolower("'"$CHANGE_ID_AFTER"'") "):"
-                numlines = split(lines, footer, "\n")
-                for (line = 1; line <= numlines; line++) {
-                        if (unprinted && match(tolower(footer[line]), changeIdAfter) != 1) {
-                                unprinted = 0
-                                print "Change-Id: I'"$id"'"
-                        }
-                        print footer[line]
-                }
-                if (unprinted) {
-                        print "Change-Id: I'"$id"'"
-                }
-        }' "$MSG" > "$T" && mv "$T" "$MSG" || rm -f "$T"
-}
-_gen_ChangeIdInput() {
-        echo "tree `git write-tree`"
-        if parent=`git rev-parse "HEAD^0" 2>/dev/null`
-        then
-                echo "parent $parent"
-        fi
-        echo "author `git var GIT_AUTHOR_IDENT`"
-        echo "committer `git var GIT_COMMITTER_IDENT`"
-        echo
-        printf '%s' "$clean_message"
-}
-_gen_ChangeId() {
-        _gen_ChangeIdInput |
-        git hash-object -t commit --stdin
-}
+# Avoid the --in-place option which only appeared in Git 2.8
+# Avoid the --if-exists option which only appeared in Git 2.15
+if ! git -c trailer.ifexists=doNothing interpret-trailers \
+        --trailer "Change-Id: I${random}" < "$1" > "${dest}" ; then
+    echo "cannot insert change-id line in $1"
+    exit 1
+fi
 
+if ! mv "${dest}" "$1" ; then
+    echo "cannot mv ${dest} to $1"
+    exit 1
+fi
 
-add_ChangeId
 #------------------ copied gerrit commit-msg hook to handle ChangeId <--
 
-
 exit 0
 
 # vi:set shiftwidth=4 expandtab: