Reads a list of patch file names from standard input and uses “git apply” to get them added as individual commits into a Git repository.

git-apply-patch-set

#! /bin/bash

set -e

declare -r NL='
'

# extract_patch_info filename.patch
#
# Sets the PATCH_{AUTHOR,DATE,MESSAGE,GIT_ID} globals according to the
# information extracted from a given patch. Unknown fields are left
# empty.
#
extract_patch_info ()
{
	PATCH_AUTHOR=''
	PATCH_DATE=''
	PATCH_MESSAGE=''
	PATCH_GIT_ID=''

	local -r S_HEADERS=1
	local -r S_MESSAGE=2
	local -r S_EMPTY=3

	local state=${S_HEADERS}

	local line
	while read -r line ; do
		if [[ ${state} -eq ${S_HEADERS} ]] ; then
			if [[ ${line} = commit\ * ]] ; then
				read -r line PATCH_GIT_ID <<< "${line}"
			elif [[ ${line} = Author:* ]] ; then
				read -r line PATCH_AUTHOR <<< "${line}"
			elif [[ ${line} = Date:* ]] ; then
				read -r line PATCH_DATE <<< "${line}"
			elif [[ ${line} = diff\ * ]] ; then
				# Diff reached, no more info to extract
				return
			elif [[ ${line} =~ ^[[:space:]]*$ ]] ; then
				# Empty line reached, start reading commit message
				state=${S_MESSAGE}
			fi
		elif [[ ${state} -eq ${S_MESSAGE} ]] ; then
			if [[ ${line} =~ ^[[:space:]]*$ ]] ; then
				# Got an empty line
				state=${S_EMPTY}
			else
				# Part of the message+
				PATCH_MESSAGE="${PATCH_MESSAGE}${line}${NL}"
			fi
		elif [[ ${state} -eq ${S_EMPTY} ]] ; then
			if [[ ${line} = diff\ * ]] ; then
				# Diff reached, no more info to extract
				return
			else
				# Still reading part of the message
				PATCH_MESSAGE="${PATCH_MESSAGE}${NL}${line}${NL}"
				state=${S_MESSAGE}
			fi
		else
			# XXX This is kind of an invalid state... bail out, maybe a warning
			# should also be displayed, or maybe the entire operation aborted.
			return
		fi
	done < "$1"
}


while read -r patch ; do
	extract_patch_info "${patch}"
	echo "${patch} (${PATCH_GIT_ID})"
	git apply  --index "${patch}" "$@"
	git commit --author="${PATCH_AUTHOR}" \
               --date="${PATCH_DATE}" \
	           --message="${PATCH_MESSAGE}"
done