# This Makefile fragment (since dpkg 1.16.1) defines the following package
# information variables:
#
#   DEB_SOURCE: source package name.
#   DEB_VERSION: package's full version (epoch + upstream vers. + revision).
#   DEB_VERSION_EPOCH_UPSTREAM: package's version without the Debian revision.
#   DEB_VERSION_UPSTREAM_REVISION: package's version without the Debian epoch.
#   DEB_VERSION_UPSTREAM: package's upstream version.
#   DEB_DISTRIBUTION: distribution(s) listed in the current debian/changelog
#     entry.
#
#   SOURCE_DATE_EPOCH: source release date as seconds since the epoch, as
#     specified by <https://reproducible-builds.org/specs/source-date-epoch/>
#     (since dpkg 1.18.8).
#     If it is undefined, the date of the latest changelog entry is used.
#     In both cases, the value is exported.

ifndef dpkg_pkg_info_mk_included
dpkg_pkg_info_mk_included = yes

dpkg_parsechangelog_run = $(eval $(shell dpkg-parsechangelog | sed -n '\
  s/^Distribution: \(.*\)/$$(eval DEB_DISTRIBUTION:=\1)/p;\
  s/^Source: \(.*\)/$$(eval DEB_SOURCE:=\1)/p;\
  s/^Version: \([0-9]*:\)\{0,1\}\([^-]*\)\(\(.*\)-[^-]*\)\{0,1\}$$/\
    $$(eval DEB_VERSION:=\1\2\3)\
    $$(eval DEB_VERSION_EPOCH_UPSTREAM:=\1\2\4)\
    $$(eval DEB_VERSION_UPSTREAM_REVISION:=\2\3)\
    $$(eval DEB_VERSION_UPSTREAM:=\2\4)/p;\
  s/^Timestamp: \(.*\)/$$(eval SOURCE_DATE_EPOCH?=\1)/p'))

ifdef SOURCE_DATE_EPOCH
  dpkg_lazy_eval ?= $(eval $(1) = $(2)$$($(1)))
  $(call dpkg_lazy_eval,DEB_DISTRIBUTION,$$(dpkg_parsechangelog_run))
  $(call dpkg_lazy_eval,DEB_SOURCE,$$(dpkg_parsechangelog_run))
  $(call dpkg_lazy_eval,DEB_VERSION,$$(dpkg_parsechangelog_run))
  $(call dpkg_lazy_eval,DEB_VERSION_EPOCH_UPSTREAM,$$(dpkg_parsechangelog_run))
  $(call dpkg_lazy_eval,DEB_VERSION_UPSTREAM,$$(dpkg_parsechangelog_run))
  $(call dpkg_lazy_eval,DEB_UPSTREAM_REVISION,$$(dpkg_parsechangelog_run))
else
  # We need to compute the values right now.
  $(dpkg_parsechangelog_run)
endif
export SOURCE_DATE_EPOCH

endif # dpkg_pkg_info_mk_included