Index: head/Mk/Scripts/smart_makepatch.sh
===================================================================
--- head/Mk/Scripts/smart_makepatch.sh
+++ head/Mk/Scripts/smart_makepatch.sh
@@ -0,0 +1,251 @@
+#!/bin/sh
+# MAINTAINER: portmgr@FreeBSD.org
+# $FreeBSD$
+
+# This script regenerates patches.  It conserves existing comments and
+# file names, even if the file name does not meet any current or
+# previous convention.  It will keep multiple patches in the same file
+# rather than splitting them into individual files.
+#
+# If a generated patch was not present before, it will create a file
+# name where forward slashes are replaced with an underscore and
+# underscores are appended by another underscore.
+#
+# Limitations:
+# 1) If a file is modified by multiple patches, it will be regenerated
+#    as a single patch.  That means if two multi-patch files modified
+#    the same source file, when regenerated, the source file's patch
+#    will only appear in one of patch file.
+# 2) It's possible that trailing garbage at the end of a patch in a
+#    multipatch file might corrupt the comment (or be interpreted as
+#    a comment) of the following patch.  (garbage in, garbage out)
+#
+# Reminder
+# Don't forget to disable post-patch targets before regenerating patches
+# if those targets modify source files (e.g. with sed).  You may also
+# want to disable EXTRA_PATCHES as well if that is being used.
+
+
+if [ -z "${PATCHDIR}" -o -z "${PATCH_WRKSRC}" -o -z "${WRKDIR}" ]; then
+	echo "WRKDIR, PATCHDIR, and PATCH_WRKSRC required in environment." >&2
+	exit 1
+fi
+
+WORKAREA=${WRKDIR}/.makepatch-tmp
+PATCHMAP=${WORKAREA}/pregen.map
+COMMENTS=${WORKAREA}/comments
+REGENNED=${WORKAREA}/regenerated
+DESTDIR=${WORKAREA}/staged
+SAVEDIR=${WORKAREA}/archived-patches
+
+case "${STRIP_COMPONENTS}" in
+	[123456789])	;;
+	1[0123456789])	;;
+	*)		STRIP_COMPONENTS=0
+esac
+
+strip_path() {
+	local raw_name=$1
+	if [ "${STRIP_COMPONENTS}" = "0" ]; then
+		echo ${raw_name}
+	else
+		echo ${raw_name} | awk -v sc=${STRIP_COMPONENTS} -F "/" \
+		'{ for (x = sc + 1; x <= NF; x++) { \
+			slash = (x>sc+1) ? "/" : ""; \
+			printf ("%s%s", slash, $x); \
+		   }}'
+	fi
+}
+
+std_patch_filename() {
+	local sans_cwd=$(echo $1 | sed 's|^\.\/||')
+	local raw_name=$(strip_path ${sans_cwd})
+	echo patch-$(echo ${raw_name} | sed -e 's|_|&&|g; s|/|_|g')
+}
+
+patchdir_files_list() {
+	if [ -d "${PATCHDIR}" ]; then
+		(cd ${PATCHDIR} && \
+			find * -type f -name "patch-*" -maxdepth 0 \
+			2>/dev/null | sed -e '/\.orig$/d'
+		)
+	fi;
+}
+
+valid_name() {
+	local current_patch_name=$1
+	local first_target=$(echo $2 | sed 's|^\.\/||')
+	local result=$3
+	local testres
+	local lps
+	for lps in __ - + ; do
+		testres=patch-$(echo ${first_target} | sed -e "s|/|${lps}|g")
+		if [ "${testres}" = "${current_patch_name}" ]; then
+			result=${testres}
+			break
+		fi
+	done
+	echo ${result}
+}
+
+map_existing_patches() {
+	mkdir -p ${WORKAREA}
+	: > ${PATCHMAP}
+	local target
+	local future_name
+	local std_target
+	local P
+	local t
+	for P in ${old_patch_list}; do
+		target=$(cd ${PATCHDIR} && \
+			grep "^+++ " ${P} | awk '{print $2}'
+		)
+		# For single patches, we honor previous separators, but use
+		# a standard patch name if the current patch name does not
+		# conform.  However, if two or more patches are contained in
+		# single file, then we do *NOT* rename the file
+		future_name=
+		for t in ${target}; do
+			if [ -n "${future_name}" ]; then
+				future_name=${P}
+				break;
+			fi
+			std_target=$(std_patch_filename ${t})
+			future_name=$(valid_name ${P} ${t} ${std_target})
+		done
+		for t in ${target}; do
+			std_target=$(std_patch_filename ${t})
+			echo "${future_name}	${std_target}" >> ${PATCHMAP}
+		done
+	done
+}
+
+extract_comment_from_patch() {
+	local existing_patch=${PATCHDIR}/$1
+	local contains=$(grep "^+++ " ${existing_patch} | awk '{x++; print x}')
+	local rawname
+	local fname
+	local num
+	for num in ${contains}; do
+		rawname=$(grep "^+++ " ${existing_patch} | \
+			awk -v num=${num} '{x++; if (x==num) print $2}')
+		fname=$(std_patch_filename $rawname)
+		awk -v num=${num} '\
+		BEGIN { done=0; x=0; hunk=0; looking=(num==1) } \
+		{ \
+		    if (!done) { \
+		        if ($1 == "@@") { \
+		            split ($3,a,","); \
+		            hc = a[2]; \
+		            hunk = 1;
+		        } else if (hunk) { \
+		            first=substr($1,1,1); \
+		            if (first == "-") { hc++ } else { hc-- } \
+		            if (hc == 0) {hunk = 0} \
+		        } \
+			if ($1 == "---") { \
+			   x++; \
+			   if (x == num) { done = 1 } \
+			   if (x + 1 == num) { looking = 1 } \
+			} else if (!hunk && looking) { \
+		            if ($1!="diff" && $1!="index" && $1!="+++") {\
+		                print $0 \
+		            } \
+		        } \
+		    } \
+		}' ${existing_patch} > ${COMMENTS}/${fname}
+	done
+}
+
+extract_comments() {
+	mkdir -p ${COMMENTS}
+	rm -f ${COMMENTS}/*
+	local P
+	for P in ${old_patch_list}; do
+		extract_comment_from_patch ${P}
+	done
+}
+
+regenerate_patches() {
+	mkdir -p ${REGENNED}
+	rm -f ${REGENNED}/*
+	[ ! -d "${PATCH_WRKSRC}" ] && return
+
+	local F
+	local NEW
+	local OUT
+	local ORIG
+	local new_list=
+	new_list=$(cd ${PATCH_WRKSRC} && \
+		find -s * -type f -name '*.orig' 2>/dev/null)
+	(cd ${PATCH_WRKSRC} && for F in ${new_list}; do
+		ORIG=${F#./}
+		NEW=${ORIG%.orig}
+		cmp -s ${ORIG} ${NEW} && continue
+		OUT=${REGENNED}/$(std_patch_filename ${NEW})
+		TZ=UTC diff -udp ${ORIG} ${NEW} | sed \
+			-e '/^---/s|\.[0-9]* +0000$| UTC|' \
+			-e '/^+++/s|\([[:blank:]][-0-9:.+]*\)*$||' \
+			> ${OUT} || true
+	done)
+}
+
+get_patch_name() {
+	awk -v name=$1 '\
+	{ if ($2 == name) \
+	  { \
+	      if (!done) { print $1 }; \
+	      done = 1; \
+	  } \
+	} \
+	END { if (!done) print name }' ${PATCHMAP}
+}
+
+stage_patches() {
+	mkdir -p ${DESTDIR}
+	rm -f ${DESTDIR}/*
+	local P
+	local name
+	local patch_list=$(cd ${REGENNED} && find * -name "patch-*" 2>/dev/null)
+	for P in ${patch_list}; do
+		name=$(get_patch_name ${P})
+		[ -e ${COMMENTS}/${P} ] && cat ${COMMENTS}/${P} \
+			>> ${DESTDIR}/${name}
+		if [ "${P}" = "${name}" ]; then
+			echo "Generated ${P}"
+		else
+			echo "Generated ${P} >> ${name} (legacy)"
+		fi
+		cat ${REGENNED}/${P} >> ${DESTDIR}/${name}
+	done
+}
+
+conserve_old_patches() {
+	mkdir -p ${SAVEDIR}
+	rm -f ${SAVEDIR}/*
+	[ -z "${old_patch_list}" ] && return
+
+	local P
+	for P in ${old_patch_list}; do
+		mv ${PATCHDIR}/${P} ${SAVEDIR}/${P}
+	done
+	echo "The previous patches have been placed here:"
+	echo ${SAVEDIR}
+}
+
+install_regenerated_patches() {
+	local testdir=$(find ${DESTDIR} -empty)
+	if [ -z "${testdir}" ]; then
+		mkdir -p ${PATCHDIR}
+		find ${DESTDIR} -type f -exec mv {} ${PATCHDIR}/ \;
+	fi
+}
+
+old_patch_list=$(patchdir_files_list)
+
+map_existing_patches
+extract_comments
+regenerate_patches
+stage_patches
+conserve_old_patches
+install_regenerated_patches
Index: head/Mk/bsd.port.mk
===================================================================
--- head/Mk/bsd.port.mk
+++ head/Mk/bsd.port.mk
@@ -1114,44 +1114,12 @@
 
 .else
 
-# Look for files named "*.orig" under ${PATCH_WRKSRC} and (re-)generate
-# ${PATCHDIR}/patch-* files from them.  By popular demand, we currently
-# use '_' (underscore) to replace path separators in patch file names.
-#
-# If a file name happens to contain character which is also a separator
-# replacement character, it will be doubled in the resulting patch name.
-#
-# To minimize gratuitous patch renames, newly generated patches will be
-# written under existing file names when they use any of the previously
-# common path separators ([-+_]) or legacy double underscore (__).
-
 .if !target(makepatch)
-PATCH_PATH_SEPARATOR=	_
 makepatch:
-	@${MKDIR} ${PATCHDIR}
-	@(cd ${PATCH_WRKSRC}; \
-		for f in `${FIND} -s . -type f -name '*.orig'`; do \
-			ORIG=$${f#./}; \
-			NEW=$${ORIG%.orig}; \
-			cmp -s $${ORIG} $${NEW} && continue; \
-			! for _lps in `${ECHO} _ - + | ${SED} -e \
-				's|${PATCH_PATH_SEPARATOR}|__|'`; do \
-					PATCH=`${ECHO} $${NEW} | ${SED} -e "s|/|$${_lps}|g"`; \
-					test -f "${PATCHDIR}/patch-$${PATCH}" && break; \
-			done || ${ECHO} $${_SEEN} | ${GREP} -q /$${PATCH} && { \
-				PATCH=`${ECHO} $${NEW} | ${SED} -e \
-					's|${PATCH_PATH_SEPARATOR}|&&|g' -e \
-					's|/|${PATCH_PATH_SEPARATOR}|g'`; \
-				_SEEN=$${_SEEN}/$${PATCH}; \
-			}; \
-			OUT=${PATCHDIR}/patch-$${PATCH}; \
-			${ECHO} ${DIFF} -udp $${ORIG} $${NEW} '>' $${OUT}; \
-			TZ=UTC ${DIFF} -udp $${ORIG} $${NEW} | ${SED} -e \
-				'/^---/s|\.[0-9]* +0000$$| UTC|' -e \
-				'/^+++/s|\([[:blank:]][-0-9:.+]*\)*$$||' \
-					> $${OUT} || ${TRUE}; \
-		done \
-	)
+	@${SETENV} WRKDIR=${WRKDIR} PATCHDIR=${PATCHDIR} \
+		PATCH_WRKSRC=${PATCH_WRKSRC} \
+		STRIP_COMPONENTS="${PATCH_STRIP:S/-p//}" \
+		${SH} ${SCRIPTSDIR}/smart_makepatch.sh
 .endif