NetBSD/share/mk/bsd.README

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# $NetBSD: bsd.README,v 1.82 2001/11/01 07:17:17 lukem Exp $
# @(#)bsd.README 8.2 (Berkeley) 4/2/94
This is the README file for the new make "include" files for the BSD
source tree. The files are installed in /usr/share/mk, and are, by
convention, named with the suffix ".mk".
Note, this file is not intended to replace reading through the .mk
files for anything tricky.
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RANDOM THINGS WORTH KNOWING:
The files are simply C-style #include files, and pretty much behave like
you'd expect. The syntax is slightly different in that a single '.' is
used instead of the hash mark, i.e. ".include <bsd.prog.mk>".
One difference that will save you lots of debugging time is that inclusion
of the file is normally done at the *end* of the Makefile. The reason for
this is because .mk files often modify variables and behavior based on the
values of variables set in the Makefile. To make this work, remember that
the FIRST target found is the target that is used, i.e. if the Makefile has:
a:
echo a
a:
echo a number two
the command "make a" will echo "a". To make things confusing, the SECOND
variable assignment is the overriding one, i.e. if the Makefile has:
a= foo
a= bar
b:
echo ${a}
the command "make b" will echo "bar". This is for compatibility with the
way the V7 make behaved.
It's fairly difficult to make the BSD .mk files work when you're building
multiple programs in a single directory. It's a lot easier to split up the
programs than to deal with the problem. Most of the agony comes from making
the "obj" directory stuff work right, not because we switched to a new version
of make. So, don't get mad at us, figure out a better way to handle multiple
architectures so we can quit using the symbolic link stuff. (Imake doesn't
count.)
The file .depend in the source directory is expected to contain dependencies
for the source files. This file is read automatically by make after reading
the Makefile.
The variable DESTDIR works as before. It's not set anywhere but will change
the tree where the file gets installed.
The profiled libraries are no longer built in a different directory than
the regular libraries. A new suffix, ".po", is used to denote a profiled
object, and ".so" denotes a shared (position-independent) object.
The following variables that control how things are made/installed that
are not set by default. These should not be set by Makefiles; they're for
the user to define in MAKECONF (see bsd.own.mk, below) or on the make(1)
command line:
BUILD If defined, 'make install' checks that the targets in the
source directories are up-to-date and remakes them if they
are out of date, instead of blindly trying to install
out of date or non-existent targets.
UPDATE If defined, 'make install' only installs targets that are
more recently modified in the source directories that their
installed counterparts.
UNPRIVILEGED If defined, don't set the owner/group/mode when installing
files or directories. This allows a non-root "make install".
MKCATPAGES If "no", don't build or install the catman pages.
MKDOC If "no", don't build or install the documentation.
MKINFO If "no", don't build or install Info documentation from
Texinfo source files.
MKLINT If "no", don't build or install the lint libraries.
MKMAN If "no", don't build or install the man or catman pages.
Also acts as "MKCATPAGES=no"
MKNLS If "no", don't build or install the NLS files and locale
definition files.
MKOBJ If "no", don't enable the rule which creates objdirs.
"yes" by default.
MKOBJDIRS If "no", don't create objdirs during a "make build".
"no" by default.
MKPIC If "no", don't build or install shared libraries.
MKPICINSTALL If "no", don't install the *_pic.a libraries.
MKPROFILE If "no", don't build or install the profiling libraries.
MKSHARE If "no", act as "MKCATPAGES=no MKDOC=no MKINFO=no MKMAN=no
MKNLS=no". I.e, don't build catman pages, documentation,
Info documentation, man pages, NLS files, ...
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The include file <sys.mk> has the default rules for all makes, in the BSD
environment or otherwise. You probably don't want to touch this file.
If you intend to run a cross build, you will need to supply the following
host tools, and configure the following variables properly:
OBJCOPY objcopy - copy and translate object files
STRIP strip - Discard symbols from object files
CONFIG config - build kernel compilation directories
RPCGEN rpcgen - Remote Procedure Call (RPC) protocol compiler
MKLOCALE mklocale - make LC_CTYPE locale files
MTREE mtree - build directory tree from a spec file
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The include file <bsd.man.mk> handles installing manual pages and their
links.
It has a two targets:
maninstall:
Install the manual page sources and their links.
catinstall:
Install the preformatted manual pages and their links.
It sets/uses the following variables:
MANDIR Base path for manual installation.
MANGRP Manual group.
MANOWN Manual owner.
MANMODE Manual mode.
MANSUBDIR Subdirectory under the manual page section, i.e. "/vax"
or "/tahoe" for machine specific manual pages.
MAN The manual pages to be installed (use a .1 - .9 suffix).
MLINKS List of manual page links (using a .1 - .9 suffix). The
linked-to file must come first, the linked file second,
and there may be multiple pairs. The files are soft-linked.
The include file <bsd.man.mk> includes a file named "../Makefile.inc" if
it exists.
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The include file <bsd.own.mk> contains source tree configuration parameters,
such as the owners, groups, etc. for both manual pages and binaries, and
a few global "feature configuration" parameters.
It has no targets.
To get system-specific configuration parameters, bsd.own.mk will try to
include the file specified by the "MAKECONF" variable. If MAKECONF is not
set, or no such file exists, the system make configuration file, /etc/mk.conf
is included. These files may define any of the variables described below.
bsd.own.mk sets the following variables, if they are not already defined
(defaults are in brackets):
BSDSRCDIR The real path to the system sources, so that 'make obj'
will work correctly. [/usr/src]
BSDOBJDIR The real path to the system 'obj' tree, so that 'make obj'
will work correctly. [/usr/obj]
BINGRP Binary group. [wheel]
BINOWN Binary owner. [root]
BINMODE Binary mode. [555]
NONBINMODE Mode for non-executable files. [444]
MANDIR Base path for manual installation. [/usr/share/man/cat]
MANGRP Manual group. [wheel]
MANOWN Manual owner. [root]
MANMODE Manual mode. [${NONBINMODE}]
MANINSTALL Manual installation type: maninstall, catinstall, or both
LDSTATIC Control program linking; if set blank, link everything
dynamically. If set to "-static", link everything statically.
If not set, programs link according to their makefile.
LIBDIR Base path for library installation. [/usr/lib]
LINTLIBDIR Base path for lint(1) library installation. [/usr/libdata/lint]
LIBGRP Library group. [${BINGRP}]
LIBOWN Library owner. [${BINOWN}]
LIBMODE Library mode. [${NONBINMODE}]
DOCDIR Base path for system documentation (e.g. PSD, USD, etc.)
installation. [/usr/share/doc]
HTMLDOCDIR Base path for html system documentation installation.
[/usr/share/doc/html]
DOCGRP Documentation group. [wheel]
DOCOWN Documentation owner. [root]
DOCMODE Documentation mode. [${NONBINMODE}]
NLSDIR Base path for National Language Support files installation.
[/usr/share/nls]
NLSGRP National Language Support files group. [wheel]
NLSOWN National Language Support files owner. [root]
NLSMODE National Language Support files mode. [${NONBINMODE}]
STRIPFLAG The flag passed to the install program to cause the binary
to be stripped. This is to be used when building your
own install script so that the entire system can be made
stripped/not-stripped using a single knob. [-s]
COPY The flag passed to the install program to cause the binary
to be copied rather than moved. This is to be used when
building our own install script so that the entire system
can either be installed with copies, or with moves using
a single knob. [-c]
Additionally, the following variables may be set by bsd.own.mk or in a
make configuration file to modify the behaviour of the system build
process (default values are in brackets along with comments, if set by
bsd.own.mk):
MKCRYPTO If set to "no", no cryptography support will be built
into the system. Defaults to "yes".
NOCRYPTO If set, it is equivalent to setting MKCRYPTO to "no".
MKCRYPTO_IDEA If set to "yes", IDEA support will be built into
libcrypto_idea.a. Defaults to "no".
MKCRYPTO_RC5 If set to "yes", RC5 support will be built into
libcrypto_rc5.a. Defaults to "no".
MKKERBEROS If set to "no", disables building Kerberos (v4 or v5)
support into various system utilities that support it.
Defaults to "yes". NOTE: This does not affect the
building of the Kerberos libraries or infrastructure
programs themselves. To completely disable Kerberos,
set MKCRYPTO to "no".
NOKERBEROS If set, it is equivalent to setting MKKERBEROS to "no".
SKEY Compile in support for S/key authentication. [yes, set
unconditionally]
MANZ Compress manual pages at installation time.
SYS_INCLUDE Copy or symlink kernel include files into /usr/include.
Possible values are "symlinks" or "copies" (which is
the same as the variable being unset).
NOPROFILE Do not build profiled versions of system libraries
NOPIC Do not build PIC versions of system libraries, and
do not build shared libraries. [set if ${MACHINE_ARCH}
is "sh3" and ${OBJECT_FMT} is "COFF", unset otherwise.]
NOLINT Do not build lint libraries.
OBJECT_FMT Object file format. [set to "ELF" on architectures that
use ELF -- currently if ${MACHINE_ARCH} is "alpha",
"mipsel", "mipseb", "powerpc", "sparc", "sparc64",
"i386" and some m68k machines, or set to "a.out" on
other architectures].
MKSOFTFLOAT If "yes", build with options to enable the compiler to
generate output containing library calls for floating
point and possibly soft-float library support. Defaults
to "no".
bsd.own.mk is generally useful when building your own Makefiles so that
they use the same default owners etc. as the rest of the tree.
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The include file <bsd.prog.mk> handles building programs from one or
more source files, along with their manual pages. It has a limited number
of suffixes, consistent with the current needs of the BSD tree.
It has eight targets:
all:
build the program and its manual page
clean:
remove the program, any object files and the files a.out,
Errs, errs, mklog, and ${PROG}.core.
cleandir:
remove all of the files removed by the target clean, as
well as .depend, tags, and any manual pages.
`distclean' is a synonym for `cleandir'.
depend:
make the dependencies for the source files, and store
them in the file .depend.
includes:
install any header files.
install:
install the program and its manual pages; if the Makefile
does not itself define the target install, the targets
beforeinstall and afterinstall may also be used to cause
actions immediately before and after the install target
is executed.
lint:
run lint on the source files
tags:
create a tags file for the source files.
It sets/uses the following variables:
BINGRP Binary group.
BINOWN Binary owner.
BINMODE Binary mode.
CLEANFILES Additional files to remove for the clean and cleandir targets.
COPTS Additional flags to the compiler when creating C objects.
CPPFLAGS Additional flags to the C pre-processor
LDADD Additional loader objects. Usually used for libraries.
For example, to load with the compatibility and utility
libraries, use:
LDADD+=-lutil -lcompat
LDFLAGS Additional loader flags.
LINKS The list of binary links; should be full pathnames, the
linked-to file coming first, followed by the linked
file. The files are hard-linked. For example, to link
/bin/test and /bin/[, use:
LINKS= ${DESTDIR}/bin/test ${DESTDIR}/bin/[
SYMLINKS The list of symbolic links; should be full pathnames.
Syntax is identical to LINKS. Note that DESTDIR is not
automatically included in the link.
MAN Manual pages (should end in .1 - .9). If no MAN variable is
defined, "MAN=${PROG}.1" is assumed.
PROG The name of the program to build. If not supplied, nothing
is built.
PROGNAME The name that the above program will be installed as, if
different from ${PROG}.
SRCS List of source files to build the program. If SRCS is not
defined, it's assumed to be ${PROG}.c.
DPADD Additional dependencies for the program. Usually used for
libraries. For example, to depend on the compatibility and
utility libraries use:
DPADD+=${LIBCOMPAT} ${LIBUTIL}
The following libraries are predefined for DPADD:
LIBCRT0?= ${DESTDIR}/usr/lib/crt0.o
LIBC?= ${DESTDIR}/usr/lib/libc.a
LIBC_PIC?= ${DESTDIR}/usr/lib/libc_pic.a
LIBCOMPAT?= ${DESTDIR}/usr/lib/libcompat.a
LIBCRYPT?= ${DESTDIR}/usr/lib/libcrypt.a
LIBCURSES?= ${DESTDIR}/usr/lib/libcurses.a
LIBDBM?= ${DESTDIR}/usr/lib/libdbm.a
LIBDES?= ${DESTDIR}/usr/lib/libdes.a
LIBEDIT?= ${DESTDIR}/usr/lib/libedit.a
LIBFORM?= ${DESTDIR}/usr/lib/libform.a
LIBGCC?= ${DESTDIR}/usr/lib/libgcc.a
LIBGNUMALLOC?= ${DESTDIR}/usr/lib/libgnumalloc.a
LIBINTL?= ${DESTDIR}/usr/lib/libintl.a
LIBIPSEC?= ${DESTDIR}/usr/lib/libipsec.a
LIBKDB?= ${DESTDIR}/usr/lib/libkdb.a
LIBKRB?= ${DESTDIR}/usr/lib/libkrb.a
LIBKVM?= ${DESTDIR}/usr/lib/libkvm.a
LIBL?= ${DESTDIR}/usr/lib/libl.a
LIBM?= ${DESTDIR}/usr/lib/libm.a
LIBMENU?= ${DESTDIR}/usr/lib/libmenu.a
LIBMP?= ${DESTDIR}/usr/lib/libmp.a
LIBNTP?= ${DESTDIR}/usr/lib/libntp.a
LIBPC?= ${DESTDIR}/usr/lib/libpc.a
LIBPCAP?= ${DESTDIR}/usr/lib/libpcap.a
LIBPLOT?= ${DESTDIR}/usr/lib/libplot.a
LIBPOSIX?= ${DESTDIR}/usr/lib/libposix.a
LIBRESOLV?= ${DESTDIR}/usr/lib/libresolv.a
LIBRPCSVC?= ${DESTDIR}/usr/lib/librpcsvc.a
LIBSKEY?= ${DESTDIR}/usr/lib/libskey.a
LIBTERMCAP?= ${DESTDIR}/usr/lib/libtermcap.a
LIBTELNET?= ${DESTDIR}/usr/lib/libtelnet.a
LIBUTIL?= ${DESTDIR}/usr/lib/libutil.a
LIBWRAP?= ${DESTDIR}/usr/lib/libwrap.a
LIBY?= ${DESTDIR}/usr/lib/liby.a
LIBZ?= ${DESTDIR}/usr/lib/libz.a
SHAREDSTRINGS If defined, a new .c.o rule is used that results in shared
strings, using xstr(1). Note that this will not work with
parallel makes.
STRIPFLAG The flag passed to the install program to cause the binary
to be stripped.
SUBDIR A list of subdirectories that should be built as well.
Each of the targets will execute the same target in the
subdirectories.
SCRIPTS A list of interpreter scripts [file.{sh,csh,pl,awk,...}].
These are installed exactly like programs.
SCRIPTSNAME The name that the above program will be installed as, if
different from ${SCRIPTS}. These can be further specialized
by setting SCRIPTSNAME_<script>.
FILES A list of files to install. The installation is controlled
by the FILESNAME, FILESOWN, FILESGRP, FILESMODE, FILESDIR
variables that can be further specialized by FILES<VAR>_<file>
The include file <bsd.prog.mk> includes the file named "../Makefile.inc"
if it exists, as well as the include file <bsd.man.mk>.
Some simple examples:
To build foo from foo.c with a manual page foo.1, use:
PROG= foo
.include <bsd.prog.mk>
To build foo from foo.c with a manual page foo.2, add the line:
MAN= foo.2
If foo does not have a manual page at all, add the line:
MKMAN= no
If foo has multiple source files, add the line:
SRCS= a.c b.c c.c d.c
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The include file <bsd.subdir.mk> contains the default targets for building
subdirectories. It has the same eight targets as <bsd.prog.mk>: all,
clean, cleandir, depend, includes, install, lint, and tags. For all of
the directories listed in the variable SUBDIR, the specified directory
will be visited and the target made. There is also a default target which
allows the command "make subdir" where subdir is any directory listed in
the variable SUBDIR.
As a special case, the use of a token .WAIT as an entry in SUBDIR acts
as a synchronization barrier when multiple make jobs are run; subdirs
before the .WAIT must complete before any subdirs after .WAIT are
started. See make(1) for some caveats on use of .WAIT and other
special sources.
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The include file <bsd.links.mk> handles the LINKS and SYMLINKS variables
and is included from from bsd.lib.mk and bsd.prog.mk.
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The include file <bsd.files.mk> handles the FILES variables and is included
from bsd.lib.mk and bsd.prog.mk.
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The include file <bsd.inc.mk> defines the includes target and uses two
variables:
INCS The list of include files
INCSDIR The location to install the include files.
INCSNAME Target name of the include file, if only one; same as
FILESNAME, but for include files.
INCSNAME_<file> The name file <file> should be installed as, if not <file>,
same as FILESNAME_<file>, but for include files.
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The include file <bsd.kinc.mk> defines the many targets (includes,
subdirectories, etc.), and is used by kernel makefiles to handle
include file installation. It is intended to be included alone, by
kernel Makefiles. Please see bsd.kinc.mk for more details, and keep
the documentation in that file up to date.
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The include file <bsd.info.mk> is used to generate and install GNU Info
documentation from respective Texinfo source files. It defines three
implicit targets (.txi.info, .texi.info, and .texinfo.info), and uses the
following variables:
TEXINFO List of Texinfo source files. Info documentation will
consist of single files with the extension replaced by
.info.
INFOFLAGS Flags to pass to makeinfo. []
INSTALL_INFO Name of install-info program. [install-info]
MAKEINFO Name of makeinfo program. [makeinfo]
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The include file <bsd.sys.mk> is used by <bsd.prog.mk> and
<bsd.lib.mk>. It contains overrides that are used when building
the NetBSD source tree. For instance, if "PARALLEL" is defined by
the program/library Makefile, it includes a set of rules for lex and
yacc that allow multiple lex and yacc targets to be built in parallel.
Other variables of note (incomplete list):
WARNS Crank up gcc warning options; the distinct levels are:
WARNS=1
WARNS=2
WARNS=3
FORMAT_AUDIT If FORMAT_AUDIT is set, and WFORMAT is set and > 1, turn on
WFORMAT -Wnetbsd-format-audit for extra-stringent format checking.
WFORMAT belongs in individual makefiles and/or
Makefile.inc files. (set WFORMAT=1 in individual
makefiles if a program is not security critical and is
doing bizarre things with format strings which would
be even uglier if rewritten) FORMAT_AUDIT should go in
mk.conf if you're doing format-string auditing.
FORMAT_AUDIT may go away in time.
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The include file <bsd.lib.mk> has support for building libraries. It has
the same eight targets as <bsd.prog.mk>: all, clean, cleandir, depend,
includes, install, lint, and tags. Additionally, it has a checkver target
which checks for installed shared object libraries whose version is greater
that the version of the source. It has a limited number of suffixes,
consistent with the current needs of the BSD tree.
It sets/uses the following variables:
LIB The name of the library to build.
LIBDIR Target directory for libraries.
LINTLIBDIR Target directory for lint libraries.
LIBGRP Library group.
LIBOWN Library owner.
LIBMODE Library mode.
LDADD Additional loader objects.
MAN The manual pages to be installed (use a .1 - .9 suffix).
MKLINKLIB If "no", act as "MKPICINSTALL=no MKPROFILE=no".
Also:
- don't install the .a libraries
- don't install _pic.a libraries on PIC systems
- don't build .a libraries on PIC systems
- don't install the .so symlink on ELF systems
I.e, only install the shared library (and the .so.major
symlink on ELF).
MKPICLIB If "no", don't build _pic.a libraries, and build the
shared object libraries from the .a libraries. A
symlink is installed in ${DESTDIR}/usr/lib for the
_pic.a library pointing to the .a library.
NOCHECKVER_<library>
NOCHECKVER If set, disables checking for installed shared object
libraries with versions greater than the source. A
particular library name, without the "lib" prefix, may
be appended to the variable name to disable the check for
only that library.
SRCS List of source files to build the library. Suffix types
.s, .c, and .f are supported. Note, .s files are preferred
to .c files of the same name. (This is not the default for
versions of make.)
The include file <bsd.lib.mk> includes the file named "../Makefile.inc"
if it exists, as well as the include file <bsd.man.mk>.
It has rules for building profiled objects; profiled libraries are
built by default.
Libraries are ranlib'd when made.
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The include file <bsd.obj.mk> defines targets related to the creation
and use of separated object and source directories.
If an environment variable named MAKEOBJDIRPREFIX is set, make(1) uses
${MAKEOBJDIRPREFIX}${.CURDIR} as the name of the object directory if
it exists. Otherwise make(1) looks for the existence of a
subdirectory (or a symlink to a directory) of the source directory
into which built targets should be placed. If an environment variable
named MAKEOBJDIR is set, make(1) uses its value as the name of the
object directory; failing that, make first looks for a subdirectory
named "obj.${MACHINE}", and if that doesn't exist, it looks for "obj".
Object directories are not created automatically by make(1) if they
don't exist; you need to run a separate "make obj". (This will happen
during a top-level build if "MKOBJDIRS" is set to a value other than
"no"). When the source directory is a subdirectory of ${BSDSRCDIR} --
and this is determined by a simple string prefix comparison -- object
directories are created in a separate object directory tree, and a
symlink to the object directory in that tree is created in the source
directory; otherwise, "make obj" assumes that you're not in the main
source tree and that it's not safe to use a separate object tree.
Several variables used by <bsd.obj.mk> control exactly what
directories and links get created during a "make obj":
MAKEOBJDIR If set, this is the component name of the object
directory.
OBJMACHINE If this is set but MAKEOBJDIR is not set, creates
object directories or links named "obj.${MACHINE}";
otherwise, just creates ones named "obj".
USR_OBJMACHINE If set, and the current directory is a subdirectory of
${BSDSRCDIR}, create object directory in the
corresponding subdirectory of ${BSDOBJDIR}.${MACHINE};
otherwise, create it in the corresponding subdirectory
of ${BSDOBJDIR}
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The include file <bsd.kernobj.mk> defines variables related to the
location of kernel sources and object directories.
KERNSRCDIR Is the location of the top of the kernel src.
It defaults to ${BSDSRCDIR}/sys, but the top-level
Makefile.inc sets it to ${ABSTOP}/sys (ABSTOP is the
absolute path to the directory where the top-level
Makefile.inc was found.
KERNARCHDIR Is the location of the machine dependent kernel
sources. It defaults to arch/${MACHINE}
KERNCONFDIR Is where the configuration files for kernels are
found; default is ${KERNSRCDIR}/${KERNARCHDIR}/conf.
KERNOBJDIR Is the kernel build directory. The kernel GENERIC for
instance will be compiled in ${KERNOBJDIR}/GENERIC.
The default value is
${MAKEOBJDIRPREFIX}${KERNSRCDIR}/${KERNARCHDIR}/compile
if it exists or the target 'obj' is being made.
Otherwise the default is
${KERNSRCDIR}/${KERNARCHDIR}/compile.
It is important that Makefiles (such as those under src/distrib) that
wish to find compiled kernels use bsd.kernobj.mk and ${KERNOBJDIR}
rather than make assumptions about the location of the compiled kernel.
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