buildroot/package/pkg-python.mk
Samuel Martin 05754fa01d pkg-python: support host-python dependency different from the python in the target
Some packages need a host-python interpreter with a version different
from the one installed in the target to run some build scripts (eg.
scons requires python2 to run, to build any kind of packages even if
the python interpreter selected for the target is python3).

In such cases, we need to add the right host-python dependency to the
package using the host-python-package infrastructure, and we also want
to invoke the right host python interpreter during the build steps.

This patch adds a *_NEEDS_HOST_PYTHON variable that can be set either
to 'python2' or 'python3'. This variable can be set by any package
using the host-python-package infrastructure to force the python
interpreter for the build. This variable also takes care of setting
the right host-python dependency.

This *_NEEDS_HOST_PYTHON variable only affects packages using the
host-python-package infrastructure.

If some configure/build/install commands are overloaded in the *.mk
file, the right python interpreter should be explicitly called.

If the package defines some tool variable (eg.: SCONS), the variable
should explicitly call the right python interpreter.

[Thomas:
 - fixes to the commit log and documentation suggested by Yann
 - rename the variable from <pkg>_FORCE_HOST_PYTHON to
   <pkg>_NEEDS_HOST_PYTHON, as suggested by Yann
 - do not allow any other value than python2 and python3 in
   <pkg>_NEEDS_HOST_PYTHON, as suggested by Yann.]

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Cc: Gustavo Zacarias <gustavo@zacarias.com.ar>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2014-04-05 16:38:25 +02:00

260 lines
8.8 KiB
Makefile

################################################################################
# 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="$(TARGET_CROSS)gcc -shared" \
PYTHONPATH="$(if $(BR2_PACKAGE_PYTHON3),$(PYTHON3_PATH),$(PYTHON_PATH))" \
_python_sysroot=$(STAGING_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="$(if $(BR2_PACKAGE_PYTHON3),$(PYTHON3_PATH),$(PYTHON_PATH))" \
_python_sysroot=$(STAGING_DIR) \
_python_prefix=/usr \
_python_exec_prefix=/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)"
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 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
$$(error "$(2)_SETUP_TYPE must be set")
endif
endif
# Distutils
ifeq ($$($(2)_SETUP_TYPE),distutils)
ifeq ($(4),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 = $$(HOST_PKG_PYTHON_DISTUTILS_INSTALL_OPT)
endif
# Setuptools
else ifeq ($$($(2)_SETUP_TYPE),setuptools)
ifeq ($(4),target)
$(2)_BASE_ENV = $$(PKG_PYTHON_SETUPTOOLS_ENV)
$(2)_BASE_BUILD_TGT = build
$(2)_BASE_BUILD_OPT =
$(2)_BASE_INSTALL_OPT = $$(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
else
$$(error "Invalid $(2)_SETUP_TYPE. Valid options are 'distutils' or 'setuptools'")
endif
# The below statement intends to calculate the dependencies of host
# packages by derivating them from the dependencies of the
# corresponding target package, after adding the 'host-' prefix in
# front of the dependencies.
#
# However it must be repeated from inner-generic-package, as we need
# to exclude the python, host-python and host-python-setuptools
# packages, which are added below in the list of dependencies
# depending on the package characteristics, and shouldn't be derived
# automatically from the dependencies of the corresponding target
# package.
$(2)_DEPENDENCIES ?= $(filter-out host-python host-python3 host-python-setuptools host-toolchain $(1),$(patsubst host-host-%,host-%,$(addprefix host-,$($(3)_DEPENDENCIES))))
# Target packages need both the python interpreter on the target (for
# runtime) and the python interpreter on the host (for
# compilation). However, host packages only need the python
# interpreter on the host, whose version may be enforced by setting
# the *_NEEDS_HOST_PYTHON variable.
#
# So:
# - for target packages, we always depend on the default python interpreter
# (the one selected by the config);
# - for host packages:
# - if *_NEEDS_HOST_PYTHON is not set, then we depend on use the default
# interperter;
# - otherwise, we depend on the one requested by *_NEEDS_HOST_PYTHON.
#
ifeq ($(4),target)
$(2)_DEPENDENCIES += $(if $(BR2_PACKAGE_PYTHON3),host-python3 python3,host-python python)
else
ifeq ($($(2)_NEEDS_HOST_PYTHON),)
$(2)_DEPENDENCIES += $(if $(BR2_PACKAGE_PYTHON3),host-python3,host-python)
else
ifeq ($($(2)_NEEDS_HOST_PYTHON),python2)
$(2)_DEPENDENCIES += host-python
else ifeq ($($(2)_NEEDS_HOST_PYTHON),python3)
$(2)_DEPENDENCIES += host-python3
else
$$(error Incorrect value '$($(2)_NEEDS_HOST_PYTHON)' for $(2)_NEEDS_HOST_PYTHON)
endif
endif # ($($(2)_NEEDS_HOST_PYTHON),)
endif # ($(4),target)
# Setuptools based packages will need host-python-setuptools (both
# host and target). 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 ($$($(2)_SETUP_TYPE),setuptools)
ifneq ($(2),HOST_PYTHON_SETUPTOOLS)
$(2)_DEPENDENCIES += host-python-setuptools
endif
endif
# Python interpreter to use for building the package.
#
# We may want to specify the python interpreter toi be used for building a
# package, especially for host-packages (target packages must be built using
# the same version of the interpreter as the one installed on the target).
#
# So:
# - for target packages, we always use the default python interpreter (which
# is the same version as the one built and installed on the target);
# - for host packages:
# - if *_NEEDS_HOST_PYTHON is not set, then we use use the default
# interperter;
# - otherwise, we use the one requested by *_NEEDS_HOST_PYTHON.
#
ifeq ($(4),target)
$(2)_PYTHON_INTERPRETER = $(HOST_DIR)/usr/bin/python
else
ifeq ($($(2)_NEEDS_HOST_PYTHON),)
$(2)_PYTHON_INTERPRETER = $(HOST_DIR)/usr/bin/python
else
$(2)_PYTHON_INTERPRETER = $(HOST_DIR)/usr/bin/$($(2)_NEEDS_HOST_PYTHON)
endif
endif
#
# Build step. Only define it if not already defined by the package .mk
# file.
#
ifndef $(2)_BUILD_CMDS
define $(2)_BUILD_CMDS
(cd $$($$(PKG)_BUILDDIR)/; \
$$($$(PKG)_BASE_ENV) $$($$(PKG)_ENV) \
$$($(2)_PYTHON_INTERPRETER) 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) \
$$($(2)_PYTHON_INTERPRETER) setup.py install \
$$($$(PKG)_BASE_INSTALL_OPT) $$($$(PKG)_INSTALL_OPT))
endef
endif
#
# Target installation step. Only define it if not already defined by
# the package .mk file.
#
ifndef $(2)_INSTALL_TARGET_CMDS
define $(2)_INSTALL_TARGET_CMDS
(cd $$($$(PKG)_BUILDDIR)/; \
$$($$(PKG)_BASE_ENV) $$($$(PKG)_ENV) \
$$($(2)_PYTHON_INTERPRETER) 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))
endef
################################################################################
# python-package -- the target generator macro for Python packages
################################################################################
python-package = $(call inner-python-package,$(pkgname),$(call UPPERCASE,$(pkgname)),$(call UPPERCASE,$(pkgname)),target)
host-python-package = $(call inner-python-package,host-$(pkgname),$(call UPPERCASE,host-$(pkgname)),$(call UPPERCASE,$(pkgname)),host)