package: introduce Python package infrastructure

[Peter: fix s/BUILD_TYPE/SETUP_TYPE/ typo in manual as noted by Samuel]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

1 files changed, 219 insertions, 0 deletions

diff --git a/package/pkg-python.mk b/package/pkg-python.mk
new file mode 100644
index 000000000..e436f22aa
--- /dev/null
+++ b/package/pkg-python.mk
@@ -0,0 +1,219 @@
+################################################################################
+# Python package infrastructure
+#
+# This file implements an infrastructure that eases development of
+# package .mk files for Python packages. It should be used for all
+# packages that use Python setup.py/setuptools as their build system.
+#
+# See the Buildroot documentation for details on the usage of this
+# infrastructure
+#
+# In terms of implementation, this Python infrastructure requires the
+# .mk file to only specify metadata informations about the package:
+# name, version, download URL, etc.
+#
+# We still allow the package .mk file to override what the different
+# steps are doing, if needed. For example, if <PKG>_BUILD_CMDS is
+# already defined, it is used as the list of commands to perform to
+# build the package, instead of the default Python behaviour. The
+# package can also define some post operation hooks.
+#
+################################################################################
+
+# Target distutils-based packages
+PKG_PYTHON_DISTUTILS_ENV = \
+	PATH="$(TARGET_PATH)" \
+	CC="$(TARGET_CC)" \
+	CFLAGS="$(TARGET_CFLAGS)" \
+	LDFLAGS="$(TARGET_LDFLAGS)" \
+	LDSHARED="$(TARGET_CROSS)gcc -shared" \
+	CROSS_COMPILING=yes \
+	_python_sysroot=$(STAGING_DIR) \
+	_python_srcdir=$(PYTHON_DIR) \
+	_python_prefix=/usr \
+	_python_exec_prefix=/usr
+
+PKG_PYTHON_DISTUTILS_BUILD_OPT = \
+	--executable=/usr/bin/python
+
+PKG_PYTHON_DISTUTILS_INSTALL_OPT = \
+	--prefix=$(TARGET_DIR)/usr
+
+# Host distutils-based packages
+HOST_PKG_PYTHON_DISTUTILS_ENV = \
+	PATH="$(HOST_PATH)"
+
+HOST_PKG_PYTHON_DISTUTILS_INSTALL_OPT = \
+	--prefix=$(HOST_DIR)/usr
+
+# Target setuptools-based packages
+PKG_PYTHON_SETUPTOOLS_ENV = \
+	PATH="$(TARGET_PATH)" \
+	PYTHONPATH="$(TARGET_DIR)/usr/lib/python$(PYTHON_VERSION_MAJOR)/site-packages" \
+	PYTHONXCPREFIX="$(STAGING_DIR)/usr/"
+
+PKG_PYTHON_SETUPTOOLS_INSTALL_OPT = \
+	--prefix=$(TARGET_DIR)/usr \
+	--executable=/usr/bin/python \
+	--single-version-externally-managed \
+	--root=/
+
+# Host setuptools-based packages
+HOST_PKG_PYTHON_SETUPTOOLS_ENV = \
+	PATH="$(HOST_PATH)" \
+	PYTHONXCPREFIX="$(HOST_DIR)/usr/"
+
+HOST_PKG_PYTHON_SETUPTOOLS_INSTALL_OPT = \
+	--prefix=$(HOST_DIR)/usr
+
+################################################################################
+# inner-python-package -- defines how the configuration, compilation
+# and installation of a Python package should be done, implements a
+# few hooks to tune the build process and calls the generic package
+# infrastructure to generate the necessary make targets
+#
+#  argument 1 is the lowercase package name
+#  argument 2 is the uppercase package name, including an HOST_ prefix
+#             for host packages
+#  argument 3 is the uppercase package name, without the HOST_ prefix
+#             for host packages
+#  argument 4 is the package directory prefix
+#  argument 5 is the type (target or host)
+################################################################################
+
+define inner-python-package
+
+$(2)_SRCDIR	= $$($(2)_DIR)/$($(2)_SUBDIR)
+$(2)_BUILDDIR	= $$($(2)_SRCDIR)
+
+$(2)_ENV         ?=
+$(2)_BUILD_OPT   ?=
+$(2)_INSTALL_OPT ?=
+
+ifndef $(2)_SETUP_TYPE
+ ifdef $(3)_SETUP_TYPE
+  $(2)_SETUP_TYPE = $($(3)_SETUP_TYPE)
+ else
+  $$(error "$(1): Unknown or undefined <pkg>_SETUP_TYPE")
+ endif
+endif
+
+# Distutils
+ifeq ($$($(2)_SETUP_TYPE),distutils)
+ifeq ($(5),target)
+$(2)_BASE_ENV         = $$(PKG_PYTHON_DISTUTILS_ENV)
+$(2)_BASE_BUILD_TGT   = build
+$(2)_BASE_BUILD_OPT   = $$(PKG_PYTHON_DISTUTILS_BUILD_OPT)
+$(2)_BASE_INSTALL_OPT = $$(PKG_PYTHON_DISTUTILS_INSTALL_OPT)
+else
+$(2)_BASE_ENV         = $$(HOST_PKG_PYTHON_DISTUTILS_ENV)
+$(2)_BASE_BUILD_TGT   = build
+$(2)_BASE_BUILD_OPT   =
+$(2)_BASE_INSTALL_OPT = $$(HOST_PKG_PYTHON_DISTUTILS_INSTALL_OPT)
+endif
+# Setuptools
+else ifeq ($$($(2)_SETUP_TYPE),setuptools)
+ifeq ($(5),target)
+$(2)_BASE_ENV         = $$(PKG_PYTHON_SETUPTOOLS_ENV)
+$(2)_BASE_BUILD_TGT   = build -x
+$(2)_BASE_BUILD_OPT   =
+$(2)_BASE_INSTALL_OPT = $$(PKG_PYTHON_SETUPTOOLS_INSTALL_OPT)
+else
+$(2)_BASE_ENV         = $$(HOST_PKG_PYTHON_SETUPTOOLS_ENV)
+$(2)_BASE_BUILD_TGT   = build
+$(2)_BASE_BUILD_OPT   =
+$(2)_BASE_INSTALL_OPT = $$(HOST_PKG_PYTHON_SETUPTOOLS_INSTALL_OPT)
+endif
+endif
+
+# The below statement intends to calculate the dependencies of host
+# packages by derivating them from the dependencies of the
+# corresponding target package, after adding the 'host-' prefix in
+# front of the dependencies.
+#
+# However it must be repeated from inner-generic-package, as we need
+# to exclude the python, host-python, host-python-setuptools and
+# host-distutilscross packages, which are added below in the list of
+# dependencies depending on the package characteristics, and shouldn't
+# be derived automatically from the dependencies of the corresponding
+# target package. For example, target packages need
+# host-python-distutilscross, but not host packages.
+$(2)_DEPENDENCIES ?= $(filter-out host-python host-python-setuptools host-python-distutilscross $(1),$(patsubst host-host-%,host-%,$(addprefix host-,$($(3)_DEPENDENCIES))))
+
+# Target packages need both the python interpreter on the target (for
+# runtime) and the python interpreter on the host (for
+# compilation). However, host packages only need the python
+# interpreter on the host.
+ifeq ($(5),target)
+$(2)_DEPENDENCIES += host-python python
+else
+$(2)_DEPENDENCIES += host-python
+endif
+
+# Setuptools based packages will need host-python-setuptools (both
+# host and target) and host-python-distutilscross (only target
+# packages). We need to have a special exclusion for the
+# host-setuptools package itself: it is setuptools-based, but
+# shouldn't depend on host-setuptools (because it would otherwise
+# depend on itself!).
+ifeq ($$($(2)_SETUP_TYPE),setuptools)
+ifneq ($(2),HOST_PYTHON_SETUPTOOLS)
+$(2)_DEPENDENCIES += host-python-setuptools
+ifeq ($(5),target)
+$(2)_DEPENDENCIES += host-python-distutilscross
+endif
+endif
+endif
+
+#
+# Build step. Only define it if not already defined by the package .mk
+# file.
+#
+ifndef $(2)_BUILD_CMDS
+define $(2)_BUILD_CMDS
+	(cd $$($$(PKG)_BUILDDIR)/; \
+		$$($$(PKG)_BASE_ENV) $$($$(PKG)_ENV) \
+		$(HOST_DIR)/usr/bin/python setup.py \
+		$$($$(PKG)_BASE_BUILD_TGT) \
+		$$($$(PKG)_BASE_BUILD_OPT) $$($$(PKG)_BUILD_OPT))
+endef
+endif
+
+#
+# Host installation step. Only define it if not already defined by the
+# package .mk file.
+#
+ifndef $(2)_INSTALL_CMDS
+define $(2)_INSTALL_CMDS
+	(cd $$($$(PKG)_BUILDDIR)/; \
+		$$($$(PKG)_BASE_ENV) $$($$(PKG)_ENV) \
+		$(HOST_DIR)/usr/bin/python setup.py install \
+		$$($$(PKG)_BASE_INSTALL_OPT) $$($$(PKG)_INSTALL_OPT))
+endef
+endif
+
+#
+# Target installation step. Only define it if not already defined by
+# the package .mk file.
+#
+ifndef $(2)_INSTALL_TARGET_CMDS
+define $(2)_INSTALL_TARGET_CMDS
+	(cd $$($$(PKG)_BUILDDIR)/; \
+		$$($$(PKG)_BASE_ENV) $$($$(PKG)_ENV) \
+		$(HOST_DIR)/usr/bin/python setup.py install \
+		$$($$(PKG)_BASE_INSTALL_OPT) $$($$(PKG)_INSTALL_OPT))
+endef
+endif
+
+# Call the generic package infrastructure to generate the necessary
+# make targets
+$(call inner-generic-package,$(1),$(2),$(3),$(4),$(5))
+
+endef
+
+################################################################################
+# python-package -- the target generator macro for Python packages
+################################################################################
+
+python-package = $(call inner-python-package,$(call pkgname),$(call UPPERCASE,$(call pkgname)),$(call UPPERCASE,$(call pkgname)),$(call pkgparentdir),target)
+host-python-package = $(call inner-python-package,host-$(call pkgname),$(call UPPERCASE,host-$(call pkgname)),$(call UPPERCASE,$(call pkgname)),$(call pkgparentdir),host)