This is a guide to explain various useful variables in Userland component

Makefiles.  To distinguish these from the Makefile(s) that are part of each

component distribution, the latter will be referred to as native Makefiles.

The following are the basics that just about every Makefile should have.

* COMPONENT_NAME is typically a short name (e.g., vim).

* COMPONENT_VERSION is typically numbers separated by dots (e.g. 7.3).

* COMPONENT_SRC is where the archive is extracted.  A common value for this is

  "$(COMPONENT_NAME)-$(COMPONENT_VERSION)".

* COMPONENT_PROJECT_URL is the general web site for the component.

* COMPONENT_ARCHIVE is the base name of the archive to be downloaded.  A common

  value for this is "$(COMPONENT_SRC).tar.gz".

* COMPONENT_ARCHIVE_HASH is typically "sha256:" followed by the first output

  field of `sha256sum $(COMPONENT_ARCHIVE)`.

* COMPONENT_ARCHIVE_URL is where the archive can be downloaded from.  This is

  typically constructed from $(COMPONENT_PROJECT_URL) and $(COMPONENT_ARCHIVE).

* COMPONENT_SIG_URL is the URL where the PGP signature for $(COMPONENT_ARCHIVE)

  can be found.  This can be used in addition to the hash in

  $(COMPONENT_ARCHIVE_HASH) to verify the correctness of the archive.  If

  COMPONENT_SIG_URL is present, then COMPONENT_ARCHIVE_HASH needn't be, but its

  presence is strongly encouraged to ensure that the archive contents don't

  change silently.  Note that when merging, because

  $WS/tools/.gnupg/pubring.gpg is a binary file, you will have to choose

  the parent or child version.  Pick one, then run:

	for cset in $(hg log -r 'parents()' -T '{node} '); do

		hg cat -r $cset $WS/tools/.gnupg/pubring.gpg | \

			gpg2 --homedir=$WS/tools/.gnupg --import;

	done

  before you 'hg commit' your merge.

* COMPONENT_BUGDB is the lower-case rendering of the BugDB cat/subcat.

* REQUIRED_PACKAGES is a list of packages required to build or run the

  component and its tests.

* GIT_REPO can be used in place of COMPONENT_ARCHIVE_URL to pull the component

  source from the GIT repository referenced in the value.

* GIT_REV is the tag or changeset that you wish to pull from GIT.

* HG_REPO can be used in place of COMPONENT_ARCHIVE_URL to pull the component

  source from the Mercurial repository referenced in the value.

* HG_REV is the tag or changeset that you wish to pull from Mercurial.

* SVN_REPO can be used in place of COMPONENT_ARCHIVE_URL to pull the component

  source from the Subversion repository referenced in the value.

* SVN_REV is the tag or changeset that you wish to pull from Subversion.

When using a source code management system as the canonical source for a

component, the build automatically generates a source archive for the

component by pulling the source from the SCM and creating a tarball from

the pulled source.  This allows us to automatically store a copy of the

canonical source that we build from in our source archive cache and not

continually hammer on the component's SCM repo.  The source archive name

is automatically generated from the COMPONENT_NAME, COMPONENT_VERSION,

and {GIT|HG|SVN}_REV values.  Also, the source is archived and unpacked

in a directory using these values.   You should also define a hash for

this tarball in your Makefile similar to what you do with downloaded

source archives.

These two are both initialized in make-rules/shared-macros.mk rather than any

component-level Makefile, but are frequently referenced from the latter.

* COMPONENT_DIR is the top-level directory of the given component in question.

* SOURCE_DIR is set to $(COMPONENT_DIR)/$(COMPONENT_SRC).

Additional pre/post configure, build, or install actions can be specified in

a component Makefile by setting them in one of the following macros.  None of

these have default values.  These are mostly used for miscellaneous set-up or

clean-up tweaks as their names suggest.

* COMPONENT_PRE_CONFIGURE_ACTION is used by several components to clone a

  source directory.

* COMPONENT_POST_CONFIGURE_ACTION

* COMPONENT_PRE_BUILD_ACTION

* COMPONENT_POST_BUILD_ACTION

* COMPONENT_PRE_INSTALL_ACTION

* COMPONENT_POST_INSTALL_ACTION

* COMPONENT_PRE_TEST_ACTION

* COMPONENT_POST_TEST_ACTION

If component specific make targets need to be used for build or install or

test, they can be specified via the following.

* COMPONENT_BUILD_TARGETS is not usually set because the default target of most

  open source software is the equivalent of a 'build' target.  This needs to be

  set when building the software requires a different target than the default.

  You should not override make macros here, but in COMPONENT_BUILD_ARGS.

* COMPONENT_INSTALL_TARGETS has a default value of "install".  Very few

  components need to alter this.

* COMPONENT_TEST_TARGETS has a default value of "check".  Several components

  need to set this to "test".

* COMPONENT_BUILD_ARGS is probably the mostly useful variable here for solving

  subtle build issues.  When you need to override a MACRO set in the native

  Makefile of a component, do so by adding something like:

     COMPONENT_BUILD_ARGS += MKDIR="$(MKDIR)"

  Quoting is often important because values with white-space can be split up,

  yielding the wrong results.

* COMPONENT_BUILD_ENV is for when you just need to override things in the

  calling environment, like PATH.

* COMPONENT_INSTALL_ARGS is mainly used for altering target directories;

  there are also COMPONENT_INSTALL_ARGS.$(BITS) versions.

* COMPONENT_INSTALL_ENV is mainly used for altering target directories.

* COMPONENT_PUBLISH_ENV is so far only used to work around Python issues when

  used by "pkgdepend generate", though the variable may be extended in the

  future for general "gmake publish" usage.

* COMPONENT_TEST_ARGS is little used.

* COMPONENT_TEST_ENV is mainly used for altering PATH and friends.

If your component needs to do some kind of cleanup after a "gmake test" run,

such as kill processes after doing a "gmake test" run, then this can be done

by setting COMPONENT_TEST_CLEANUP.

If you have created master test results file(s) for your component in the

COMPONENT_TEST_RESULTS_DIR directory, then in order to successfully compare

your test results against that master results file, you might need to

normalize some of the test output lines. This is done via a set of regular

expressions that are applied to the test results. There are some global

default ones in the COMPONENT_TEST_TRANSFORMS definition in shared-macros.mk,

but your component Makefile might have to += some more for specific transforms

that need to be applied to the test output for just this component.

* SKIP_TEST_AT_TOP_LEVEL inclusion of this variable in a component Makefile

  will cause that component's tests to be skipped when running "gmake test"

  at the top level.  It's often used for excluding long-running tests 

  that may slow down comprehensive component testing.  

* COMPONENT_POST_UNPACK_ACTION is for making minor alterations to the unpacked

  source directory before any patching has taken place.  It should almost never

  be used.

* COMPONENT_PREP_ACTION is used to make alterations to the unpacked and patched

  source.  It should be used with care.

For components that have a configure target, the following macros are used to

control the options and arguments passed:

* If BITS is set before shared-macros.mk is included, the default directories

  used for various configure options as documented below will change.  For

  example:

  if BITS=64 explicitly:

  	32-bit binaries -> $(CONFIGURE_PREFIX)/bin/$(MACH32)

	32-bit libraries -> $(CONFIGURE_PREFIX)/lib

  	64-bit binaries -> $(CONFIGURE_PREFIX)/bin

	64-bit libraries -> $(CONFIGURE_PREFIX)/lib/$(MACH64)

  if BITS=32 explicitly or BITS is unspecified:

  	32-bit binaries -> $(CONFIGURE_PREFIX)/bin

	32-bit libraries -> $(CONFIGURE_PREFIX)/lib

  	64-bit binaries -> $(CONFIGURE_PREFIX)/bin/$(MACH64)

	64-bit libraries -> $(CONFIGURE_PREFIX)/lib/$(MACH64)

* CC_FOR_BUILD is included in CONFIGURE_ENV by default to ensure that 32-bit

  and 64-bit host detection works as expected for autoconf-based components by

  specifying the exact compiler and relevant $(CC_BITS) for the current build.

  It can be set to "" to omit it from CONFIGURE_ENV.

* CONFIGURE_CPPFLAGS contains the default set of CPPFLAGS to be included in

  CONFIGURE_ENV.  It can be set to "" to omit it from CONFIGURE_ENV.

* CONFIGURE_DEFAULT_DIRS should be "yes" or "no".  A value of "yes" (the

  default) will trigger the following being passed to CONFIGURE_OPTIONS as

  parameters to corresponding options.

  * CONFIGURE_BINDIR.$(BITS) is the value for the --bindir= option.

  * CONFIGURE_LIBDIR.$(BITS) is the value for the --libdir= option.

  * CONFIGURE_MANDIR.$(BITS) is the value for the --mandir= option.

  * CONFIGURE_SBINDIR.$(BITS) is the value for the --sbindir= option.

* CONFIGURE_ENV is mainly used for passing CFLAGS and other common Makefile

  variables to configure.  When should this be used as opposed to

  CONFIGURE_OPTIONS and COMPONENT_BUILD_{ARGS,ENV}?  In general, you want

  to tell configure how to build the software using CONFIGURE_OPTIONS.  But

  sometimes you need to pass values in via the calling environment.  On rare

  occasions, you still need to do things like override MACRO settings in the

  generated Makefiles with COMPONENT_BUILD_ARGS.

* CONFIGURE_LOCALEDIR is a cousin of the other *DIR variables above, but

  rarely used and hence not triggered by CONFIGURE_DEFAULT_DIRS.

* CONFIGURE_OPTIONS is extremely useful, possibly our most used "add-on"

  variable, for passing various options to configure.  These tend to vary per

  component, but --enable-foo and --disable-foo for various values of foo are

  quite common.

* CONFIGURE_PREFIX is the prefix for the various *DIR variables above.  Its

  default is "/usr"; set it if some other value (e.g., "/usr/gnu") is needed.

* CONFIGURE_SCRIPT should be set if the default "$(SOURCE_DIR)/configure" is

  unsuitable for whatever reason.

To override or otherwise modify the default compilation flags used for

components, the following macros are provided:

* CFLAGS by default contains the preferred set of compilation flags for most

  components, which usually includes optimization flags, language mode,

  alignment flags, and multi-threading flags for the current COMPILER.

  CFLAGS.$(COMPILER) and CFLAGS.$(COMPILERS).$(BITS) versions are also

  available for specifying additional flags or overriding the default.

* CXXFLAGS by default contains the preferred set of compilation flags for most

  C++ components, which usually includes optimization flags, language mode,

  alignment flags, and multi-threading flags for the current COMPILER.

  CXXFLAGS.$(COMPILER) and CXXFLAGS.$(COMPILERS).$(BITS) versions are also

  available for specifying additional flags or overriding the default.

* gcc_OPT has a default value of "-O3".  Bugs in the optimizer have been found

  which have required altering this to "-O2".

* studio_OPT has a default value of "-xO4".  Occasional bugs in the optimizer

  have been found which have required altering this to "-xO3".

* There are also gcc_OPT.$(MACH).$(BITS) and studio_OPT.$(MACH).$(BITS)

  versions of the above available if greater specificity is needed.

For components that use pkg-config, the following macros are provided:

* PKG_CONFIG_PATH contains the default system paths to use when looking for

  pkg-config configuration files.  To specify additional paths to be searched,

  use PKG_CONFIG_PATHS as follows:

  PKG_CONFIG_PATHS += /path/to/pc/files

Finally, for control of packaging-related operations and values used during

publication, the following variables are available:

* All variables named after the pattern COMPONENT_%(COMPONENT_NAME_%), such

  as COMPONENT_ARCHIVE_URL, COMPONENT_ARCHIVE_URL_1, etc.  Refer to ips.mk

  PKG_MACROS and PKG_VARS for a complete list.

* DQ, SQ, Q: a set of convenience macros that expand to ", ', and "

  respectively; $(Q) (or $Q) is simply the default quote with a short name

  for convenience.  For use with values in package manifests where the

  substituted value may contain whitespace.  For example:

  set name=pkg.human-version value=$(DQ)$(HUMAN_VERSION)$(DQ)

* PKG_MACROS: the list of makefile macros that should be exported as defines

  for use in package manifests and pkgmogrify transform files.  Whitespace is

  NOT supported; use of PKG_VARS is strongly preferred for this reason.  The

  expected form each of entry is a key-value pair as follows:

     PKG_MACROS += NAME=NO-WHITESPACE-VALUE

* PKG_VARS: the list of variables that should be exported as defines for use in

  package manifests and pkgmogrify transform files.  This list should generally

  only be added to, not redefined, as follows:

     PKG_VARS += VARIABLE_NAME

  Variable values may contain whitespace, although the value must be quoted

  appropriately in the package manifest if they do.  Variables must be assigned

  before the inclusion of ips.mk.  Values containing whitespace should not be

  quoted when declared in the Makefile; they should only be quoted using the

  appropriate macros in the package manifest.  Values cannot currently contain

  any characters that require shell escaping such as ", ', or *.

* PYVER is defined when processing package manifest files whose name end in

  -PYVER.p5m.  The package manifest will be processed for each version found in

  PYTHON_VERSIONS.  MAYBE_PYVER_SPACE (e.g. '2.7 ') and MAYBE_SPACE_PYVER

  (e.g. ' 2.7') are derived from PYVER if defined.  If PYVER is not defined

  (such as when a generic unversioned Python package manifest is being

  created), these are defined as ''.  perl and ruby follow the same pattern

  and define PERLVER, PERL_VERSIONS, MAYBE_SPACE_PERLVER, MAYBE_PERLVER_SPACE

  and RUBY_VERSION, RUBY_VERSIONS, MAYBE_RUBY_VERSION_SPACE,

  MAYBE_SPACE_RUBY_VERSION respectively.

* TPNO is the Third Party number (i.e., a numeric value): the License

  Technology from the Product Lifecycle Suite tool.  This should be used

  in the common case when there is just one TPNO for a component.  We

  recommend that this be near the top of any Makefile, just below the

  various COMPONENT_foo definitions.

* TPNO_foo is for the rare case (~3% of components) when a component has

  more than one TPNO.  Each one should have a separate short but descriptive

  name substituted for "foo".  This likewise should be near the top of any

  Makefile, just below the various COMPONENT_foo definitions, and it must

  also be before the inclusion of ips.mk.  All variables named after the

  pattern TPNO_% are automatically available for use in package manifests

  and pkgmogrify transform files.

* PKGREPO_REMOVE_BEFORE_PUBLISH allows automatic removal of previously

  published components from PKG_REPO (including obsolete and renamed

  versions). When set as PKGREPO_REMOVE_BEFORE_PUBLISH=yes removal

  occurs immediately prior to pkgsend. default: "no"

---

Now switching from explaining the function of specific variables to a more

general discussion about how to use them to solve problems.  One method that

has served time and again is adding a level of indirection.  For example,

when Python 3 came along, we decided to build it 64-bit only, which meant

its various modules also needed to be built 64-bit only.  But many of them

had BUILD_32_and_64 in their native Makefile.  So how to tweak that macro

to do one thing for Python 2.x but another for 3.x?  JBeck spent an entire

day trying various combinations that seemed right, but none of them worked.

Then Norm pointed out that changing PYTHON_VERSIONS from "3.4 2.7 2.6" to

$(PYTHON3_VERSIONS) and $(PYTHON2_VERSIONS) which in turn were "3.4" and

"2.7 2.6" would do the trick.  I.e., adding a level of indirection solved

the problem, as it allowed $(PYTHON_VERSIONS) to be used to specify 64-bit

macros but $(PYTHON2_VERSIONS) to specify 32-bit macros.  There are many

other places where constructs like this are used.