468 lines
13 KiB
Plaintext
468 lines
13 KiB
Plaintext
mk-files
|
|
********
|
|
|
|
The term ``mk-files`` refers to a collection of ``*.mk`` files.
|
|
|
|
You need bmake_ or a *recent* NetBSD_ make.
|
|
If in doubt use bmake_.
|
|
|
|
Introduction
|
|
============
|
|
|
|
Many years ago, when building large software projects, I used GNU make
|
|
(or my own patched version of it), and had developed a set of macros
|
|
to simplify developing complex build trees.
|
|
|
|
Since the early 90's my main development machines, run BSD
|
|
(NetBSD_ to be precise), and the BSD source tree is good example of a
|
|
large software project. It quickly became clear that
|
|
``/usr/share/mk/*.mk`` were a great model, but were quite tightly
|
|
linked to building the BSD tree.
|
|
|
|
Much as I liked using NetBSD, my customers were more likely to be
|
|
using SunOS, HP-UX etc, so I started on bmake_ and a portable collection
|
|
of mk-files (mk.tar.gz_). NetBSD provided much of the original structure.
|
|
|
|
Since then I've added a lot of features to NetBSD's make and hence to
|
|
bmake which is kept closely in sync. The mk-files however have
|
|
diverged quite a bit, though ideas are still picked up from NetBSD.
|
|
|
|
Basics
|
|
------
|
|
|
|
The BSD build model is very simple. A directory produces one
|
|
component, which is generally either a library or a program.
|
|
Library makefiles include ``lib.mk`` and programs include ``prog.mk``
|
|
and they *do the right thing*.
|
|
|
|
A simple library makefile might look like::
|
|
|
|
LIB = sig
|
|
|
|
SRCS = \
|
|
sigaction.c \
|
|
sigcompat.c \
|
|
sighdl.c
|
|
|
|
.include <lib.mk>
|
|
|
|
a simple program makefile::
|
|
|
|
PROG = cat
|
|
|
|
SRCS = cat.c
|
|
|
|
.include <prog.mk>
|
|
|
|
in such cases even the ``SRCS`` line is unnecessary as ``prog.mk``
|
|
will default it to ``${PROG}.c``.
|
|
|
|
It is the sensible use of defaults and the plethora of macro modifiers
|
|
provided by bmake_ that allow simple makefiles such as the above
|
|
*just work* on many different systems.
|
|
|
|
|
|
mk-files
|
|
========
|
|
|
|
This section provides a brief description of some of the ``*.mk``
|
|
files.
|
|
|
|
sys.mk
|
|
------
|
|
|
|
When bmake starts, it looks for ``sys.mk`` and reads it before doing
|
|
anything else. Thus, this is the place to setup the environment for
|
|
everyone else.
|
|
|
|
In this distribution, sys.mk avoids doing anything platform dependent.
|
|
It is quite short, and includes a number of other files (which may or
|
|
may not exists)
|
|
|
|
sys.env.mk
|
|
If it exists, is expected to do things like conditioning the
|
|
environment. Since it will only be included by the initial
|
|
instance of bmake, it should ``.export`` anything that
|
|
sub-makes might need.
|
|
|
|
examples/sys.clean-env.mk
|
|
An example of how to clean the environment.
|
|
See the file for all the details::
|
|
|
|
.if ${MAKE_VERSION} >= 20100606 && ${.MAKE.LEVEL} == 0
|
|
# we save any env var that starts with these
|
|
MAKE_SAVE_ENV_PREFIX += SB MK MAKE MACHINE NEED_ CCACHE DISTCC USE_ SSH
|
|
MAKE_SAVE_ENV_VARS += \
|
|
PATH HOME USER LOGNAME \
|
|
SRCTOP OBJTOP OBJROOT \
|
|
${_env_vars}
|
|
|
|
_env_vars != env | egrep '^(${MAKE_SAVE_ENV_PREFIX:ts|})' | sed 's,=.*,,'; echo
|
|
_export_list =
|
|
.for v in ${MAKE_SAVE_ENV_VARS:O:u}
|
|
.if !empty($v)
|
|
_export_list += $v
|
|
$v := ${$v}
|
|
.endif
|
|
.endfor
|
|
# now clobber the environment
|
|
.unexport-env
|
|
|
|
# list of vars that we handle specially below
|
|
_tricky_env_vars = MAKEOBJDIR
|
|
# export our selection - sans tricky ones
|
|
.export ${_export_list:${_tricky_env_vars:${M_ListToSkip}}}
|
|
|
|
# this next bit may need tweaking
|
|
.if defined(MAKEOBJDIR)
|
|
srctop := ${SRCTOP:U${SB_SRC:U${SB}/src}}
|
|
objroot := ${OBJROOT:U${SB_OBJROOT:U${SB}/${SB_OBJPREFIX}}}
|
|
# we'll take care of MACHINE below
|
|
objtop := ${OBJTOP:U${objroot}${MACHINE}}
|
|
.if !empty(objtop)
|
|
# we would normally want something like (/bin/sh):
|
|
# MAKEOBJDIR="\${.CURDIR:S,${SRCTOP},${OBJROOT}\${MACHINE},}"
|
|
# the $$ below is how we achieve the same result here.
|
|
# since everything saved from the environment above
|
|
# has run through := we need to compensate for ${MACHINE}
|
|
MAKEOBJDIR = $${.CURDIR:S,${srctop},${objtop:S,${MACHINE},\${MACHINE},},}
|
|
|
|
# export these as-is, and do not track...
|
|
.export-env ${_tricky_env_vars}
|
|
# now evaluate for ourselves
|
|
.for v in ${_tricky_env_vars}
|
|
$v := ${$v}
|
|
.endfor
|
|
|
|
.endif
|
|
.endif
|
|
.endif
|
|
|
|
|
|
host-target.mk
|
|
Is used to set macros like ``HOST_TARGET``, ``HOST_OS`` and
|
|
``host_os`` which are used to find the next step.
|
|
|
|
sys/\*.mk
|
|
Platform specific additions, such as ``Darwin.mk`` or ``SunOS.mk``
|
|
set things like ``HOST_LIBEXT = .dylib`` for Darwin or
|
|
``SHLIB_FULLVERSION = ${SHLIB_MAJOR}`` for SunOS 5.
|
|
If there is no OS specific file, ``sys/Generic.mk`` is used.
|
|
|
|
local.sys.mk
|
|
Any ``local.*.mk`` file is not part of the distribution.
|
|
This provides a hook for sites to do extra setup without
|
|
having to edit the distributed files.
|
|
|
|
|
|
The above arrangement makes it easy for the mk files to be part of a
|
|
src tree on an NFS volume and to allow building on multiple platforms.
|
|
|
|
lib.mk
|
|
------
|
|
|
|
This file is used to build a number of different libraries from the
|
|
same SRCS.
|
|
|
|
lib${LIB}.a
|
|
An archive lib of ``.o`` files, this is the default
|
|
|
|
lib${LIB}_p.a
|
|
A profiled lib of ``.po`` files.
|
|
Still an archive lib, but all the objects are built with
|
|
profiling in mind - hence the different extension.
|
|
It is skipped if ``MKPROFILE`` is "no".
|
|
|
|
lib${LIB}_pic.a
|
|
An archive of ``.so`` objects compiled for relocation.
|
|
On NetBSD this is the input to ``lib${LIB}.${LD_so}``, it is
|
|
skipped if ``MKPICLIB`` is "no".
|
|
|
|
lib${LIB}.${LD_so}
|
|
A shared library. The value of ``LD_so`` is very platform
|
|
specific. For example::
|
|
|
|
# SunOS 5 and most other ELF systems
|
|
libsslfd.so.1
|
|
|
|
# Darwin
|
|
libsslfd.1.dylib
|
|
|
|
This library will only be built if ``SHLIB_MAJOR`` has
|
|
a value, and ``MKPIC`` is not set to "no".
|
|
|
|
There is a lot of platform specific tweaking in ``lib.mk``, largely the
|
|
result of the original distributions trying to avoid interfering with
|
|
the system's ``sys.mk``.
|
|
|
|
libnames.mk
|
|
-----------
|
|
|
|
This is included by both ``prog.mk`` and ``lib.mk`` and tries to
|
|
include ``*.libnames.mk`` of which:
|
|
|
|
local.libnames.mk
|
|
does not exist unless you create it. It is a handy way for you
|
|
to customize without touching the distributed files.
|
|
For example, on a test machine I needed to build openssl but
|
|
not install it, so put the following in ``local.libnames.mk``::
|
|
|
|
.if ${host_os} == "sunos"
|
|
LIBCRYPTO = ${OBJTOP}/openssl/lib/crypto/libcrypto${DLIBEXT}
|
|
LIBSSL = ${OBJTOP}/openssl/lib/ssl/libssl${DLIBEXT}
|
|
INCLUDES_libcrypto = -I${OBJ_libcrypto}
|
|
.endif
|
|
|
|
The makefile created an openssl dir in ``${OBJ_libcrypto}`` to
|
|
gather all the headers. dpadd.mk_ did the rest.
|
|
|
|
sjg.libnames.mk
|
|
not part of the mk-files distribution.
|
|
|
|
host.libnames.mk
|
|
contains logic to find any libs named in ``HOST_LIBS`` in
|
|
``HOST_LIBDIRS``.
|
|
|
|
Each file above gets an opportunity to define things like::
|
|
|
|
LIBSSLFD ?= ${OBJTOP}/ssl/lib/sslfd/libsslfd${DLIBEXT}
|
|
INCLUDES_libsslfd = -I${SRC_libsslfd}/h -I${OBJ_libslfd}
|
|
|
|
these are used by dpadd.mk_ and will be explained below.
|
|
|
|
dpadd.mk
|
|
--------
|
|
|
|
This file looks like line noise, and is best considered read-only.
|
|
However it provides some very useful functionality, which simplifies the build.
|
|
|
|
Makefiles can use the LIB* macros defined via libnames.mk_ or anywhere
|
|
else in various ways::
|
|
|
|
# indicate that we need to include headers from LIBCRYPTO
|
|
# this would result in ${INCLUDES_libcrypto} being added to CFLAGS.
|
|
SRC_LIBS += ${LIBCRYPTO}
|
|
|
|
# indicate that libsslfd must be built already.
|
|
# it also has the same effect as SRC_LIBS
|
|
DPADD += ${LIBSSLFD}
|
|
|
|
# indicate that not only must libsslfd be built,
|
|
# but that we need to link with it.
|
|
# this is almost exactly equivalent to
|
|
# DPADD += ${LIBSSLFD}
|
|
# LDADD += -L${LIBSSLFD:H} -lsslfd
|
|
# and mostly serves to ensure that DPADD and LDADD are in sync.
|
|
DPLIBS += ${LIBSSLFD}
|
|
|
|
Any library (referenced by its full path) in any of the above, is
|
|
added to ``DPMAGIC_LIBS`` with the following results, for each lib *foo*.
|
|
|
|
SRC_libfoo
|
|
Is set to indicate where the src for libfoo is.
|
|
By default it is derived from ``LIBFOO`` by replacing
|
|
``${OBJTOP}`` with ``${SRCTOP}``.
|
|
|
|
OBJ_libfoo
|
|
Not very exciting, is just the dir where libfoo lives.
|
|
|
|
INCLUDES_libfoo
|
|
What to add to ``CFLAGS`` to find the public headers.
|
|
The default varies. If ``${SRC_libfoo}/h`` exists, it is assumed
|
|
to be the home of all public headers and thus the default is
|
|
``-I${SRC_libfoo}/h``
|
|
|
|
Otherwise we make no assumptions and the default is
|
|
``-I${SRC_libfoo} -I${OBJ_libfoo}``
|
|
|
|
LDADD_libfoo
|
|
This only applies to libs reference via ``DPLIBS``.
|
|
The default is ``-lfoo``, ``LDADD_*`` provides a hook to
|
|
instantiate other linker flags at the appropriate point
|
|
without losing the benfits of ``DPLIBS``.
|
|
|
|
prog.mk
|
|
-------
|
|
|
|
Compiles the specified SRCS and links them and the nominated libraries
|
|
into a program. Prog makefiles usually need to list the libraries
|
|
that need to be linked. We prefer use of ``DPLIBS`` but the more
|
|
traditional ``DPADD`` and ``LDADD`` work just as well.
|
|
That is::
|
|
|
|
DPLIBS += ${LIBCRYPTO}
|
|
|
|
is equivalent to::
|
|
|
|
DPADD += ${LIBCRYPTO}
|
|
LDADD += -lcrypto
|
|
|
|
obj.mk
|
|
------
|
|
|
|
One of the cool aspects of BSD make, is its support for separating
|
|
object files from the src tree. This is also the source of much
|
|
confusion to some.
|
|
|
|
Traditionally one had to do a separate ``make obj`` pass through the
|
|
tree. If ``MKOBJDIRS`` is "auto", we include auto.obj.mk_.
|
|
|
|
auto.obj.mk
|
|
-----------
|
|
|
|
This leverages the ``.OBJDIR`` target introduced some years ago to
|
|
NetBSD make, to automatically create the desired object dir.
|
|
|
|
subdir.mk
|
|
---------
|
|
|
|
This is the traditional means of walking the tree. A makefile sets
|
|
``SUBDIR`` to the list of sub-dirs to visit.
|
|
|
|
If ``SUBDIR_MUST_EXIST`` is set, missing directories cause an error,
|
|
otherwise a warning is issued. If you don't even want the warning,
|
|
set ``MISSING_DIR=continue``.
|
|
|
|
Traditionally, ``subdir.mk`` prints clue as it visits each subdir::
|
|
|
|
===> ssl
|
|
===> ssl/lib
|
|
===> ssl/lib/sslfd
|
|
|
|
you can suppress that - or enhance it by setting ``ECHO_DIR``::
|
|
|
|
# suppress subdir noise
|
|
ECHO_DIR=:
|
|
# print time stamps
|
|
ECHO_DIR=echo @ `date "+%s [%Y-%m-%d %T] "`
|
|
|
|
links.mk
|
|
--------
|
|
|
|
Provides rules for processing lists of ``LINKS`` and ``SYMLINKS``.
|
|
Each is expected to be a list of ``link`` and ``target`` pairs
|
|
(``link`` -> ``target``).
|
|
|
|
The logic is generally in a ``_*_SCRIPT`` which is referenced in a
|
|
``_*_USE`` (``.USE``) target.
|
|
|
|
The ``_BUILD_*`` forms are identical, but do not use ``${DESTDIR}``
|
|
and so are useful for creating symlinks during the build phase.
|
|
For example::
|
|
|
|
SYMLINKS += ${.CURDIR}/${MACHINE_ARCH}/include machine
|
|
header_links: _BUILD_SYMLINKS_USE
|
|
|
|
md.o: header_links
|
|
|
|
would create a symlink called ``machine`` in ``${.OBJDIR}`` pointing to
|
|
``${.CURDIR}/${MACHINE_ARCH}/include`` before compiling ``md.o``
|
|
|
|
|
|
autoconf.mk
|
|
-----------
|
|
|
|
Deals with running (or generating) GNU autoconf ``configure`` scripts.
|
|
|
|
dep.mk
|
|
------
|
|
|
|
Deals with collecting dependencies. Another useful feature of BSD
|
|
make is the separation of this sort of information into a ``.depend``
|
|
file. ``MKDEP`` needs to point to a suitable tool (like mkdeps.sh_)
|
|
|
|
If ``USE_AUTODEP_MK`` is "yes" includes autodep.mk_
|
|
|
|
autodep.mk
|
|
----------
|
|
|
|
Leverages the ``-MD`` feature of recent GCC to collect dependency
|
|
information as a side effect of compilation. With this GCC puts
|
|
dependency info into a ``.d`` file.
|
|
|
|
Unfortunately GCC bases the name of the ``.d`` file on the name of the
|
|
input rather than the output file, which causes problems when the same
|
|
source is compiled different ways. The latest GCC supports ``-MF`` to
|
|
name the ``.d`` file and ``-MT`` to control the name to put as the
|
|
dependent.
|
|
|
|
Recent bmake allows dependencies for the ``.END`` target (run at the
|
|
end if everything was successful), and ``autodep.mk`` uses this to
|
|
post process the ``.d`` files into ``.depend``.
|
|
|
|
auto.dep.mk
|
|
-----------
|
|
|
|
A much simpler implementation than autodep.mk_ it uses
|
|
``-MF ${.TARGET:T}.d``
|
|
to avoid possible conflicts during parallel builds.
|
|
This precludes the use of suffix rules to drive ``make depend``, so
|
|
dep.mk_ handles that if specifically requested.
|
|
|
|
own.mk
|
|
------
|
|
|
|
Normally included by ``init.mk`` (included by ``lib.mk`` and
|
|
``prog.mk`` etc), sets macros for default ownership etc.
|
|
|
|
It includes ``${MAKECONF}`` if it is defined and exists.
|
|
|
|
man.mk
|
|
------
|
|
|
|
Deals with man pages.
|
|
|
|
warnings.mk
|
|
-----------
|
|
|
|
This provides a means of fine grained control over warnings on a per
|
|
``${MACHINE}`` or even file basis.
|
|
|
|
A makefile sets ``WARNINGS_SET`` to name a list of warnings
|
|
and individual ``W_*`` macros can be used to tweak them.
|
|
For example::
|
|
|
|
WARNINGS_SET = HIGH
|
|
W_unused_sparc = -Wno-unused
|
|
|
|
would add all the warnings in ``${HIGH_WARNINGS}`` to CFLAGS, but
|
|
on sparc, ``-Wno-unused`` would replace ``-Wunused``.
|
|
|
|
You should never need to edit ``warnings.mk``, it will include
|
|
``warnings-sets.mk`` if it exists and you use that to make any local
|
|
customizations.
|
|
|
|
Meta mode
|
|
=========
|
|
|
|
The 20110505 and later versions of ``mk-files`` include a number of
|
|
makefile contributed by Juniper Networks, Inc.
|
|
These allow the latest version of bmake_ to run in `meta mode`_.
|
|
|
|
.. _`meta mode`: bmake-meta-mode.htm
|
|
|
|
Install
|
|
=======
|
|
|
|
You can use the content of mk.tar.gz_ without installing at all.
|
|
|
|
The script ``install-mk`` takes care of copying ``*.mk`` into a
|
|
destination directory, and unless told not to, create ``bsd.*.mk`` links
|
|
for ``lib.mk`` etc.
|
|
|
|
If you just want to create the ``bsd.*.mk`` links in the directory
|
|
where you unpacked the tar file, you can::
|
|
|
|
./mk/install-mk ./mk
|
|
|
|
------
|
|
|
|
.. _bmake: bmake.htm
|
|
.. _NetBSD: http://www.netbsd.org/
|
|
.. _mkdeps.sh: http://www.crufty.net/ftp/pub/sjg/mkdeps.sh
|
|
.. _mk.tar.gz: http://www.crufty.net/ftp/pub/sjg/mk.tar.gz
|
|
|
|
:Author: sjg@crufty.net
|
|
:Revision: $Id: mk-files.txt,v 1.15 2011/06/08 07:06:18 sjg Exp $
|
|
:Copyright: Crufty.NET
|