[source] build: add defaults for PKG_SOURCE, PKG_SOURCE_SUBDIR, PKG_VERSION

[LEDE Commits]

nbd pushed a commit to source.git, branch master:
https://git.lede-project.org/ffb0181a8731847ea0d02d6e158adf3d7d95c382

commit ffb0181a8731847ea0d02d6e158adf3d7d95c382
Author: Felix Fietkau <nbd at nbd.name>
AuthorDate: Wed Dec 21 16:39:56 2016 +0100

    build: add defaults for PKG_SOURCE, PKG_SOURCE_SUBDIR, PKG_VERSION
    
    This makes it easier to unify versioning of git based package downloads.
    PKG_SOURCE_DATE along with an 8-character abbreviation of the git hash
    is used as PKG_VERSION, PKG_RELEASE should be used like normal packages.
    
    Signed-off-by: Felix Fietkau <nbd at nbd.name>
---
 include/download.mk   | 6 ++++++
 include/host-build.mk | 3 ++-
 include/package.mk    | 3 ++-
 rules.mk              | 2 ++
 4 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/include/download.mk b/include/download.mk
index 63ded7e..09b929b 100644
--- a/include/download.mk
+++ b/include/download.mk
@@ -9,6 +9,12 @@
 OPENWRT_GIT = http://git.openwrt.org
 LEDE_GIT = https://git.lede-project.org
 
+ifdef PKG_SOURCE_VERSION
+PKG_VERSION ?= $(if $(PKG_SOURCE_DATE),$(PKG_SOURCE_DATE)-)$(call version_abbrev,$(PKG_SOURCE_VERSION))
+PKG_SOURCE_SUBDIR ?= $(PKG_NAME)-$(PKG_VERSION)
+PKG_SOURCE ?= $(PKG_SOURCE_SUBDIR).tar.xz
+endif
+
 DOWNLOAD_RDEP=$(STAMP_PREPARED) $(HOST_STAMP_PREPARED)
 
 # Try to guess the download method from the URL
diff --git a/include/host-build.mk b/include/host-build.mk
index e11e3ed..f6ca3ff 100644
--- a/include/host-build.mk
+++ b/include/host-build.mk
@@ -5,6 +5,8 @@
 # See /LICENSE for more information.
 #
 
+include $(INCLUDE_DIR)/download.mk
+
 HOST_BUILD_DIR ?= $(BUILD_DIR_HOST)/$(PKG_NAME)$(if $(PKG_VERSION),-$(PKG_VERSION))
 HOST_INSTALL_DIR ?= $(HOST_BUILD_DIR)/host-install
 HOST_BUILD_PARALLEL ?=
@@ -35,7 +37,6 @@ HOST_STAMP_INSTALLED:=$(HOST_BUILD_PREFIX)/stamp/.$(PKG_NAME)_installed
 
 override MAKEFLAGS=
 
-include $(INCLUDE_DIR)/download.mk
 include $(INCLUDE_DIR)/quilt.mk
 include $(INCLUDE_DIR)/autotools.mk
 
diff --git a/include/package.mk b/include/package.mk
index f51232f..41401dd 100644
--- a/include/package.mk
+++ b/include/package.mk
@@ -9,6 +9,8 @@ __package_mk:=1
 
 all: $(if $(DUMP),dumpinfo,$(if $(CHECK),check,compile))
 
+include $(INCLUDE_DIR)/download.mk
+
 PKG_BUILD_DIR ?= $(BUILD_DIR)/$(PKG_NAME)$(if $(PKG_VERSION),-$(PKG_VERSION))
 PKG_INSTALL_DIR ?= $(PKG_BUILD_DIR)/ipkg-install
 PKG_BUILD_PARALLEL ?=
@@ -92,7 +94,6 @@ endif
 
 PKG_INSTALL_STAMP:=$(PKG_INFO_DIR)/$(PKG_DIR_NAME).$(if $(BUILD_VARIANT),$(BUILD_VARIANT),default).install
 
-include $(INCLUDE_DIR)/download.mk
 include $(INCLUDE_DIR)/quilt.mk
 include $(INCLUDE_DIR)/package-defaults.mk
 include $(INCLUDE_DIR)/package-dumpinfo.mk
diff --git a/rules.mk b/rules.mk
index 41e0ef2..b1d9926 100644
--- a/rules.mk
+++ b/rules.mk
@@ -55,6 +55,8 @@ __tr_template = $(__tr_head)$$(1)$(__tr_tail)
 $(eval toupper = $(call __tr_template,$(chars_lower),$(chars_upper)))
 $(eval tolower = $(call __tr_template,$(chars_upper),$(chars_lower)))
 
+version_abbrev = $(if $(if $(CHECK),,$(DUMP)),$(1),$(shell printf '%.8s' $(1)))
+
 _SINGLE=export MAKEFLAGS=$(space);
 CFLAGS:=
 ARCH:=$(subst i486,i386,$(subst i586,i386,$(subst i686,i386,$(call qstrip,$(CONFIG_ARCH)))))