Add support for overlays

overlays are a way to help users to integrate their own ports tree
with the official ports tree without having to maintain clone of the
official tree and remerge on regular basis.

The ports tree will lookup in the overlays (in the order the are listed in
OVERLAY variable) for the dependencies and the USES. It will use the first
found.

in order to use it the user have to declare his overlays that way in their
make.conf:
OVERLAYS= overlay1 overlay2 overlay3

Reviewed by:	manu
Approved by:	swills
Differential Revision:	https://reviews.freebsd.org/D21468

4 files changed, 54 insertions, 14 deletions

diff --git a/Mk/Scripts/depends-list.sh b/Mk/Scripts/depends-list.sh
index ce4f4b75a094..843bedd03958 100644
--- a/Mk/Scripts/depends-list.sh
+++ b/Mk/Scripts/depends-list.sh
@@ -37,7 +37,7 @@ while getopts "fmrw" FLAG; do
 done
 shift $((OPTIND-1))
 
-validate_env PORTSDIR dp_PKGNAME
+validate_env PORTSDIR dp_OVERLAYS dp_PKGNAME
 if [ ${recursive} -eq 1 -o ${requires_wrkdir} -eq 1 ]; then
 	validate_env dp_MAKE
 	# Cache command executions to avoid looking them up again in every
@@ -65,16 +65,25 @@ check_dep() {
 
 		case "${2}" in
 		/*) d=${2} ;;
-		*) d=${PORTSDIR}/${2} ;;
+		*) for overlay in ${dp_OVERLAYS} ${PORTSDIR}; do
+			d=${overlay}/${2}
+			f=
+			case "${d}" in
+			*@*/*) ;; # Ignore @ in the path which would not be a flavor
+			*@*)
+				f=${d##*@}
+				d=${d%@*}
+				;;
+			esac
+			if [ -f ${d}/Makefile ]; then
+				if [ -n $f ]; then
+					export FLAVOR=$f
+				fi
+				break
+			fi
+		done
 		esac
 
-		case "${d}" in
-		*@*/*) ;; # Ignore @ in the path which would not be a flavor
-		*@*)
-			export FLAVOR=${d##*@}
-			d=${d%@*}
-			;;
-		esac
 		if [ ${flavors} -eq 1 -a -n "${FLAVOR:-}" ]; then
 			port_display="${d}@${FLAVOR}"
 		else
diff --git a/Mk/Scripts/do-depends.sh b/Mk/Scripts/do-depends.sh
index 163570052a54..af93ec646a74 100644
--- a/Mk/Scripts/do-depends.sh
+++ b/Mk/Scripts/do-depends.sh
@@ -11,7 +11,7 @@ validate_env dp_RAWDEPENDS dp_DEPTYPE dp_DEPENDS_TARGET dp_DEPENDS_PRECLEAN \
 	dp_DEPENDS_CLEAN dp_DEPENDS_ARGS dp_USE_PACKAGE_DEPENDS \
 	dp_USE_PACKAGE_DEPENDS_ONLY dp_PKG_ADD dp_PKG_INFO dp_WRKDIR \
 	dp_PKGNAME dp_STRICT_DEPENDS dp_LOCALBASE dp_LIB_DIRS dp_SH \
-	dp_SCRIPTSDIR PORTSDIR dp_MAKE dp_MAKEFLAGS
+	dp_SCRIPTSDIR PORTSDIR dp_MAKE dp_MAKEFLAGS dp_OVERLAYS
 
 [ -n "${DEBUG_MK_SCRIPTS}" -o -n "${DEBUG_MK_SCRIPTS_DO_DEPENDS}" ] && set -x
 
@@ -125,7 +125,15 @@ for _line in ${dp_RAWDEPENDS} ; do
 
 	case "${origin}" in
 	/*) ;;
-	*) origin="${PORTSDIR}/${origin}" ;;
+	*)
+		for overlay in ${dp_OVERLAYS} ${PORTSDIR}; do
+			orig="${overlay}/${origin}"
+			if [ -f "${orig}/Makefile" ]; then
+				break
+			fi
+		done
+		origin="${orig}"
+		;;
 	esac
 	case "${origin}" in
 	*@*/*) ;; # Ignore @ in the path which would not be a flavor
diff --git a/Mk/bsd.port.mk b/Mk/bsd.port.mk
index b6d630ead0b5..fb88ab5614d4 100644
--- a/Mk/bsd.port.mk
+++ b/Mk/bsd.port.mk
@@ -1029,6 +1029,7 @@ STAGEDIR?=	${WRKDIR}/stage
 NOTPHONY?=
 FLAVORS?=
 FLAVOR?=
+OVERLAYS?=
 # Disallow forced FLAVOR as make argument since we cannot change it to the
 # proper default.
 .if empty(FLAVOR) && !empty(.MAKEOVERRIDES:MFLAVOR)
@@ -1450,7 +1451,17 @@ ${_f}_ARGS:=	${f:C/^[^\:]*(\:|\$)//:S/,/ /g}
 .endif
 .endfor
 .for f in ${USES}
-.include "${USESDIR}/${f:C/\:.*//}.mk"
+.undef _usefound
+.for udir in ${OVERLAYS:C,$,/Mk/Uses,} ${USESDIR}
+_usefile=	${udir}/${f:C/\:.*//}.mk
+.if exists(${_usefile}) && !defined(_usefound)
+_usefound=
+.include "${_usefile}"
+.endif
+.endfor
+.if !defined(_usefound)
+ERROR+=	"Unkonwn USES=${f:C/\:.*//}"
+.endif
 .endfor
 
 .if !empty(FLAVORS)
@@ -1962,7 +1973,17 @@ ${_f}_ARGS:=	${f:C/^[^\:]*(\:|\$)//:S/,/ /g}
 .endif
 .endfor
 .for f in ${_USES_POST}
-.include "${USESDIR}/${f:C/\:.*//}.mk"
+.undef _usefound
+.for udir in ${OVERLAYS:C,$,/Mk/Uses,} ${USESDIR}
+_usefile=	${udir}/${f:C/\:.*//}.mk
+.if exists(${_usefile}) && !defined(_usefound)
+_usefound=
+.include "${_usefile}"
+.endif
+.endfor
+.if !defined(_usefound)
+ERROR+=	"Unkonwn USES=${f:C/\:.*//}"
+.endif
 .endfor
 
 .if defined(PORTNAME)
@@ -3964,6 +3985,7 @@ ${deptype:tl}-depends:
 		dp_SH="${SH}" \
 		dp_SCRIPTSDIR="${SCRIPTSDIR}" \
 		PORTSDIR="${PORTSDIR}" \
+		dp_OVERLAYS="${OVERLAYS}" \
 		dp_MAKE="${MAKE}" \
 		dp_MAKEFLAGS='${.MAKEFLAGS}' \
 		${SH} ${SCRIPTSDIR}/do-depends.sh
@@ -4018,6 +4040,7 @@ DEPENDS-LIST= \
 			dp_PKGNAME="${PKGNAME}" \
 			dp_PKG_INFO="${PKG_INFO}" \
 			dp_SCRIPTSDIR="${SCRIPTSDIR}" \
+			dp_OVERLAYS="${OVERLAYS}" \
 			${SH} ${SCRIPTSDIR}/depends-list.sh \
 			${DEPENDS_SHOW_FLAVOR:D-f}
 
diff --git a/Mk/bsd.sanity.mk b/Mk/bsd.sanity.mk
index 04542537d798..c3490ea1bab9 100644
--- a/Mk/bsd.sanity.mk
+++ b/Mk/bsd.sanity.mk
@@ -58,7 +58,7 @@ ERROR+=	"${a} is unsupported, please use ${${a}_ALT}"
 
 # Warnings only when DEVELOPER=yes
 
-.if exists(${.CURDIR}/../../Mk/bsd.port.mk)
+.if exists(${.CURDIR}/../../Mk/bsd.port.mk) || ${OVERLAYS:tA:M${.CURDIR:H:H}} == ${.CURDIR:H:H}
 .if ${.CURDIR:H:T} != ${PKGCATEGORY}
 DEV_ERROR+=	"The first entry in CATEGORIES should be the directory where the port lives"
 .endif