git-foreach

#!/bin/bash
#
# See $desc, below, for program description
#
# Copyright (c) 2017 Red Hat, Inc.
#
# Author(s):
#   Jeff Cody <jcody@redhat.com>
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; under version 2 of the license
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, see <http://www.gnu.org/licenses/gpl-2.0.html>.
#

set -C -u -e
set -o pipefail

desc="
$0 iterates through a git commit range, and performs the
specified command on each commit."


# default range is the last commit
def_range="HEAD^!"
def_log="output-$$.log"
def_logdir=""
def_cmd="./scripts/checkpatch.pl <(git format-patch -s --stdout HEAD^!)"
def_showerr="y"

showerr=""
cmd=""

logfile=$def_log
range=`git config foreach.range || true`
logdir=`git config foreach.logdir || true`
cmd=`git config foreach.cmd || true`
showerr=`git config foreach.showerr || true`

if [[ -z "$range" ]]
then
    range=$def_range
    git config foreach.range $range || true
fi
if [[ -z "$logdir" ]]
then
    logdir=$def_logdir
    git config foreach.logdir "$logdir" || true
fi
if [[ -z "$cmd" ]]
then
    cmd=$def_cmd
    git config foreach.cmd "$cmd" || true
fi
if [[ -z "$showerr" ]]
then
    showerr=$def_showerr
    git config foreach.showerr $showerr || true
fi

usage() {
    echo ""
    echo "$0 [OPTIONS]"
    echo "$desc"
    echo ""
    echo "OPTIONS:"
    echo "      -r git range
            optional; default is '$range'
"
    echo "      -d log dir
            optional; default is '$logdir'
"
    echo "      -l log filename
            optional; default is output-PROCID, where PROCID is the bash process id
            note: you may specify a full path for the log filename here, and exclude the
            -d option.
"
    echo "      -c cmd
            cmd to run; default is '$cmd'
"
    echo "      -n 
            don't print or stop on errors; default for showing errors is '$showerr'
"
    echo "      -h help"
}

while getopts ":r:l:d:c:hn" opt
do
    case $opt in
        r) range=$OPTARG
            ;;
        d) logdir=$OPTARG
            ;;
        l) logfile=$OPTARG
            ;;
        c) cmd=$OPTARG
            ;;
        n) showerr='n'
            ;;
        h) usage
           exit
            ;;
        \?) echo "Unknown option: -$OPTARG" >&2
            usage
            exit 1
            ;;
    esac
done

# append a '/' to logdir if $logdir was specified without one
[[ -n "$logdir" ]] && [[ ${logdir:${#logdir}-1} != "/" ]] && logdir="${logdir}/"

logfile="${logdir}${logfile}"

head=`git rev-parse --abbrev-ref=strict HEAD`
if [ HEAD = "$head" ]
then
    # we're at a detached head, get hash
    head=`git rev-parse HEAD`
fi


total=`git rev-list "$range" |wc -l`

echo "log output: $logfile"

date > "$logfile"
echo "git foreach loop, executing '$cmd' for $range." >> "$logfile"
echo "-------------------------------------------------------------" >> "$logfile"
echo "" | tee -a "$logfile"

# we want to cleanup and return the git tree back to the previous head
trap cleanup EXIT

cleanup() {
    echo ""
    echo -n "Cleaning up..."
    git checkout $head > /dev/null 2>&1
    echo "done."
}

cnt=1
# don't pipe the git job into read, to avoid subshells
while read hash
do
    txt=`git log --pretty=tformat:"%h: %s" $hash^!`
    echo "${cnt}/${total}: commit: $txt" | tee -a "$logfile"
    let cnt=$cnt+1;
    echo "####################" >> "$logfile"
    git checkout $hash          >> "$logfile" 2>&1 && \
        eval $cmd                2>&1 | tee -a "$logfile" ||
    (
        S=$?
        if [[ "$showerr" == "y" ]]
        then
            # don't complain for SIGINT, SIGTERM, SIGQUIT
            if [ $S -ne 130 ] && [ $S -ne 131 ] && [ $S -ne 143 ]
            then
                echo "" | tee -a "$logfile"
                echo "ERROR: foreach cmd on $hash failed!" | tee -a "$logfile"
                git show --stat $hash | tee -a "$logfile"
            fi
            exit 1
        fi
    )
done < <(git log $range --pretty=tformat:"%H" --reverse)

echo "
All patches in $range executed on  successfully!" | tee -a "$logfile"
exit 0