pkgbase: Unify pkg ABI handling for pkgbase targets

Right now, to get the pkg ABI we either use PKG_ABI, derived from
newvers.sh, or use an ABI file from the staged world.  This
inconsistency is confusing and can cause problems.

Switch to a single source of truth: use an ABI file from the worldstage
dir to get the ABI of pkgbase packages.  In particular, we do not need
to know the ABI until staging is done.  More specifically:
- use a shell command to define PKG_ABI,
- replace inline uses of ABI_FILE,
- run sign-packages in a subshell (this was already done for the
  update-packages target) so that the staging targets are done before we
  try to evaluate the ABI.

Reviewed by:	manu
MFC after:	1 month
Sponsored by:	Innovate UK
Differential Revision:	https://reviews.freebsd.org/D46287

Makefile.inc1

@@ -1994,6 +1994,10 @@ REPODIR?=	${OBJROOT}repo
 PKG_FORMAT?=	tzst
 PKG_REPO_SIGNING_KEY?=	# empty
 PKG_OUTPUT_DIR?=	${PKG_VERSION}
+PKG_ABI_FILE?=	${WSTAGEDIR}/usr/bin/uname
+.if make(create-*-packages*) || make(real-update-packages) || make(real-sign-packages)
+PKG_ABI!=	${PKG_CMD} -o ABI_FILE=${PKG_ABI_FILE} config ABI
+.endif
 
 .ORDER:		stage-packages create-packages
 .ORDER:		create-packages create-world-packages
@@ -2006,12 +2010,6 @@ _pkgbootstrap: .PHONY
 	@env ASSUME_ALWAYS_YES=YES pkg bootstrap
 .endif
 
-#
-# Determine PKG_ABI from newvers.sh if not already set.
-#
-.if !defined(PKG_ABI) && (make(create-world-packages-jobs) || make(create-kernel-packages*) || make(real-update-packages) || make (create-source-packages) || make(sign-packages))
-PKG_ABI=${_TYPE}:${MAJOR_REVISION}:${TARGET_ARCH}
-.endif
 PKG_BIN_VERSION!=${PKG_CMD} --version </dev/null 2>/dev/null |\
     awk -F. '/^[0-9.]+$$/ {print $$1 * 10000 + $$2 * 100 + $$3}'
 .if ${PKG_BIN_VERSION} < 11700
@@ -2021,8 +2019,7 @@ PKG_EXT=	pkg
 .endif
 
 .if !defined(PKG_VERSION_FROM) && make(real-update-packages)
-.if defined(PKG_ABI)
-.if exists(${REPODIR}/${PKG_ABI})
+.if exists(${PKG_ABI_FILE}) && exists(${REPODIR}/${PKG_ABI})
 PKG_VERSION_FROM!=/usr/bin/readlink ${REPODIR}/${PKG_ABI}/latest
 PKG_VERSION_FROM_DIR=	${REPODIR}/${PKG_ABI}/${PKG_VERSION_FROM}
 BRANCH_EXT_FROM=	${PKG_VERSION_FROM:C/.*([[:alpha:]][^\.]*).*/\1/}
@@ -2032,7 +2029,6 @@ PKG_VERSION_FROM_DIR=
 BRANCH_EXT_FROM=
 .endif
 .endif
-.endif
 
 PKGMAKEARGS+=	PKG_VERSION=${PKG_VERSION} \
 		NO_INSTALLEXTRAKERNELS=${NO_INSTALLEXTRAKERNELS}
@@ -2204,7 +2200,7 @@ create-world-package-${pkgname}: .PHONY
 	@if [ "${pkgname}" == "runtime" ]; then \
 		sed -i '' -e "s/%VCS_REVISION%/${VCS_REVISION}/" ${WSTAGEDIR}/${pkgname}.ucl ; \
 	fi
-	${PKG_CMD} -o ABI_FILE=${WSTAGEDIR}/usr/bin/uname -o ALLOW_BASE_SHLIBS=yes \
+	${PKG_CMD} -o ABI=${PKG_ABI} -o ALLOW_BASE_SHLIBS=yes \
 		-o OSVERSION="${SRCRELDATE}" \
 		create -f ${PKG_FORMAT} -M ${WSTAGEDIR}/${pkgname}.ucl \
 		-p ${WSTAGEDIR}/${pkgname}.plist \
@@ -2306,7 +2302,7 @@ create-kernel-packages-extra-flavor${flavor:C,^""$,${_default_flavor},}-${_kerne
 		/name/ { printf("===> Creating %s-", $$2); next } \
 		/version/ {print $$2; next } ' \
 		${KSTAGEDIR}/kernel.${_kernel}/kernel.${_kernel}${flavor}.ucl ; \
-	${PKG_CMD} -o ABI_FILE=${WSTAGEDIR}/usr/bin/uname -o ALLOW_BASE_SHLIBS=yes \
+	${PKG_CMD} -o ABI=${PKG_ABI} -o ALLOW_BASE_SHLIBS=yes \
 		-o OSVERSION="${SRCRELDATE}" \
 		create -f ${PKG_FORMAT} \
 		-M ${KSTAGEDIR}/kernel.${_kernel}/kernel.${_kernel}${flavor}.ucl \
@@ -2318,20 +2314,22 @@ create-kernel-packages-extra-flavor${flavor:C,^""$,${_default_flavor},}-${_kerne
 . endfor
 .endif
 
-sign-packages:	_pkgbootstrap .PHONY
+sign-packages:	.PHONY
+	${_+_}@cd ${.CURDIR}; \
+		${MAKE} -f Makefile.inc1 PKG_VERSION=${PKG_VERSION} real-sign-packages
+
+real-sign-packages:	_pkgbootstrap .PHONY
 	printf "version = 2;\n" > ${WSTAGEDIR}/meta
 .if ${PKG_BIN_VERSION} < 11700
 	printf "packing_format = \"${PKG_FORMAT}\";\n" >> ${WSTAGEDIR}/meta
 .endif
-	@[ -L "${REPODIR}/$$(${PKG_CMD} -o ABI_FILE=${WSTAGEDIR}/usr/bin/uname config ABI)/latest" ] && \
-		unlink ${REPODIR}/$$(${PKG_CMD} -o ABI_FILE=${WSTAGEDIR}/usr/bin/uname config ABI)/latest ; \
-	${PKG_CMD} -o ABI_FILE=${WSTAGEDIR}/usr/bin/uname repo \
-		-o OSVERSION="${SRCRELDATE}" \
+	@[ -L "${REPODIR}/${PKG_ABI}/latest" ] && unlink ${REPODIR}/${PKG_ABI}/latest; \
+	${PKG_CMD} -o ABI=${PKG_ABI} repo -o OSVERSION="${SRCRELDATE}" \
 		-m ${WSTAGEDIR}/meta \
-		-o ${REPODIR}/$$(${PKG_CMD} -o ABI_FILE=${WSTAGEDIR}/usr/bin/uname config ABI)/${PKG_VERSION} \
-		${REPODIR}/$$(${PKG_CMD} -o ABI_FILE=${WSTAGEDIR}/usr/bin/uname config ABI)/${PKG_VERSION} \
+		-o ${REPODIR}/${PKG_ABI}/${PKG_VERSION} \
+		${REPODIR}/${PKG_ABI}/${PKG_VERSION} \
 		${PKG_REPO_SIGNING_KEY} ; \
-	cd ${REPODIR}/$$(${PKG_CMD} -o ABI_FILE=${WSTAGEDIR}/usr/bin/uname config ABI); \
+	cd ${REPODIR}/${PKG_ABI}; \
 	ln -s ${PKG_OUTPUT_DIR} latest
 
 #