1 \input texinfo @c -*-texinfo-*-
3 @setfilename omk-manual
4 @settitle OMK: Ocera Make System
8 Manual for Ocera Make System (OMK)
10 Copyright @copyright{} 2007 Michal Sojka, Pavel Pisa
14 @title Ocera Make System Manual
16 @vskip 0pt plus 1filll
23 @node Top, Overview of OMK, (dir), (dir)
24 @top Ocera Make System
38 @node Overview of OMK, OMK User's Manual, Top, Top
42 OMK is an advanced make system written entirely in GNU make. Compiling
43 software using OMK requires only GNU make binary and standard UNIX
44 utilities (@command{sh}, @command{sed}, @command{cmp} and
45 @command{tr}@footnote{@command{tr} is needed only for OMK to be
46 compatible with MinGW.}) installed. OMK aims to be developer friendly;
47 to use OMK, you do not need to understand (sometimes) cryptic syntax of
50 You can use OMK on all platforms where you can run GNU Make including
51 Cygwin and MinGW. MS DOS was not tested.
57 @c Easy to use for beginners.
59 @c Automatic handling of dependencies.
61 @c Supported host platforms: all Un*x operating system including Linux,
62 @c Cygwin, MS DOS and maybe others.
71 @node Why to Use OMK?, Quick Start, Overview of OMK, Overview of OMK
72 @section Why to Use OMK?
74 Here we list some of OMK features, which we think are important for
75 choosing of a make system.
80 Makefile in source directories are usually very @b{simple}.
82 There is only @b{one} @file{Makefile.rules} for most of components of
85 OMK greatly simplifies compilation of projects, where source files are
86 spread between @b{multiple directories}.
88 OMK handles properly @b{dependencies} of source files and libraries,
89 so it is not necessary to recompile the whole project if only several
92 OMK allows to freely @b{move} cross-dependant components @b{in
93 directory structure} without the need to update users of moved
94 component. I hate something like
95 @option{-I../../sched/rtlshwq/include} in makefiles for example. If a
96 component is renamed or version is added to the name, many Makefiles
97 in the project would require an update.
99 The above feature is very helpful in @b{combining components}
100 (libraries) from different projects/developers to a single project by
101 simply creating symbolic links to external components.
103 Compilation of an OMK based projects don't require to install any
104 files before successful finish of build.
106 OMK allows to call @command{make} for a particular subdirectory in the
109 Under OMK all products of compilation are stored @b{out of source
110 directories}. This simplifies work with version control systems and
111 helps when simultaneous compilation for multiple targets/platforms is
116 @node Quick Start, History, Why to Use OMK?, Overview of OMK
119 If you get some sources, which are distributed with OMK, usually the
120 following commands are sufficient to compile the whole project.
129 @noindent To use OMK in your own project, follow these steps:
133 Take appropriate @file{Makefile.rules}, put it together with leaf
134 @file{Makefile} to the root directory of your project.
136 Create @file{Makefile.omk} files in all directories you want to
137 compile something. Please refer to @ref{OMK User's Manual} to learn
138 what to write in @file{Makefile.omk} files.
140 Run @command{make omkize} in the root directory.
143 @noindent Your project is now ready to compile.
146 @node History, , Quick Start, Overview of OMK
149 OMK was originally written by Pavel Pisa as a solution to have one
150 common make system for OCERA project, where we needed to compile
151 user-space programs, Linux kernel modules and RT Linux modules in one
152 package. Although this system was not accepted for the whole OCERA
153 project. Several individual developers (mostly from Czech Technical
154 University) liked it and started to use it.
156 As a number of projects using OMK grew it was necessary to modularize
157 the make system to support more ``targets''. Michal Sojka took care
158 about the process of modularization.
160 @node OMK User's Manual, Original README, Overview of OMK, Top
161 @chapter OMK User's Manual
166 * Compiling Programs::
168 * Multiple Directories::
169 * Dependency Tracking::
170 * Configuration and Conditional Compilation::
171 * Advanced OMK Features::
172 * Running OMK under Windows OS::
173 * Interfacing OMK to popular IDEs::
177 @node Basic Concepts, Invoking OMK, OMK User's Manual, OMK User's Manual
178 @section Basic Concepts
180 The main concept of OMK is very simple. In the root directory of the
181 projects resides a file called @file{Makefile.rules}. This file contains
182 all compilation rules needed for compilation of a particular
183 project. There are different @file{Makefile.rules} for different
184 platforms (Unix, RTEMS, system-less, ...). In every subdirectory a
185 @file{Makefile.omk} is stored. This file determines what should be done
186 in the respective directory (e.g. compile a program from several source
187 files). Its syntax is very simple -- see the following sections.
189 Since make searches by default for a @file{Makefile} and not for
190 @file{Makefile.rules} or @file{Makefile.omk}, there must be a small
191 generic @file{Makefile} in every directory, whose task is only to find
192 @file{Makefile.rules} in the actual or any parent directory and include
193 it. This search is performed only once at the beginning of compilation.
195 @c TODO: Pavel's note about qmake.
197 The compilation process itself is comprised of several passes. Every
198 pass traverses the whole directory structure@footnote{In future, we are
199 planning some optimization that allows OMK to traverse the directories
200 only once and thus decrease compilation time.} and does a particular
201 task in every directory of the project. Typically, these passes are:
203 @anchor{include-pass}
205 This pass takes all include files marked for ``export'' and copies
206 (or links) them to the @file{include} directory under
207 @file{_compiled} directory. @xref{Header Files}.
209 Also, during this pass, automatically generated header file are
210 generated according to the current
211 configuration. @xref{Configuration and Conditional Compilation}.
213 During this pass, all include files are in place, so all libraries
216 Finally, programs can be compiled and linked against libraries
217 created in the previous pass.
220 The results of compilation are stored under the @file{_compiled}
221 directory. This directory is structured as a classical Unix file-system
222 (it contains directories like @file{bin}, @file{lib} and @file{include})
223 and can be directly copied to the target device or to some directory on
224 a host computer (e.g. @file{/usr/local}).
226 Besides @file{_compiled} directory, there in a @file{_build}
227 directory. Under this directory are stored some temporary files and
228 intermediate compilation products (object files, dependency files etc.).
230 In the next section, we provide an overview of methods, how to invoke
231 OMK from command line. Section @ref{Interfacing OMK to popular IDEs}
232 covers running of OMK from popular IDEs.
234 Sections @ref{Compiling Programs} through @ref{Configuration and
235 Conditional Compilation} deals with the content of
236 @file{Makefile.omk}. Its syntax in usual cases compatible to GNU
237 Automake's @file{Makefile.am} syntax. Also, the scheme for naming
238 variables was inspired by Automake so most OMK variables have the name
239 like @samp{@var{target}_@var{TYPE}}.
241 @node Invoking OMK, Compiling Programs, Basic Concepts, OMK User's Manual
242 @section Invoking OMK
244 Before using OMK for the first time, you have to call:
246 @command{make default-config}
248 @noindent See @ref{Configuration and Conditional Compilation} for
249 details. If you forget to do this, OMK will notice you.
251 To compile the whole project or only some subtree of the project, call
255 @noindent in the appropriate directory.
257 To clean files in @file{_build} directory but not in @file{_compiled}
263 To clean the compilation completely, you can either remove
264 @file{_compiled} and @file{_build} directories manually, or call
266 @command{make distclean}
268 @noindent which does the same. This command removes these directories
269 even if you call it from a subdirectory.
271 To debug compilation problems, you can use @code{V} variable (see
277 You can also set values of some other variables on command line for
278 temporary change something. The example below compiles the code
279 temporarily with debugging information:
281 @command{make CFLAGS="-g -O0 -Wall"}
287 If this variable equals to @samp{1}, the whole command lines for all
288 executed commands are displayed. Otherwise, only short messages are
292 @node Compiling Programs, Libraries, Invoking OMK, OMK User's Manual
293 @section Compiling Programs
295 To tell OMK to compile a program, you need to set some variables in
296 @file{Makefile.omk} (usually) in the directory where program sources are
299 In the example bellow a program @command{test} will be compiled from
300 source @file{test.c}.
303 @verbatiminclude ../tests/programs/Makefile.omk
306 @noindent The variables are:
309 Contains a list of names (whitespace separated) of programs to be
310 compiled in this directory.
314 For every program name @var{xxx} in @code{bin_PROGRAMS}, this variable
315 contains a list of sources that are needed to compile the
316 executable. OMK uses an extension of the filename to determine the
317 compiler to compile this source.
321 This variable contains a list of libraries the program @var{xxx} will
330 This variable contains a list of libraries all programs in this
331 directory needs to be linked to.
335 Directives passed to the C or C++ compiler with additional directories
336 to be searched for header files. In most cases you need to specify an
337 absolute path. To specify a directory relative to the source
338 directory, you can use the @code{$(SOURCES_DIR)} variable, which
339 refers to the directory, where @file{Makefile.omk} is located. This
340 variable applies to all compilations invoked in the current directory.
343 INCLUDES = -I$(SOURCES_DIR)/my_include_dir
348 Directives passed to the C or C++ compiler with preprocessor macro
349 definitions. This variable applies to all compilations invoked in the
358 @c FIXME: INCLUDES variable should not be set by rtlinux rules.
360 @node Libraries, Multiple Directories, Compiling Programs, OMK User's Manual
364 With OMK, you can easily create statically or dynamically linked
365 libraries. The way of creating libraries is very similar to how programs
366 are created. @xref{Compiling Programs}.
368 In @file{Makefile.omk}, you specify several variables, which defines how
369 the libraries should be compiled. In the example below the library
370 @samp{mylib} is created from two sources @file{funca.c} and
371 @file{funcb.c}. Interface of this library is defined in
372 @file{myfunc.h}. Therfore, we export this header for use by other
376 @verbatiminclude ../tests/libraries/Makefile.omk
379 @noindent Variables for use with libraries are:
381 @defvar lib_LIBRARIES
382 Specifies a list of statically linked libraries to be compiled.
385 @defvar shared_LIBRARIES
386 Specifies a list of dynamically linked libraries to be compiled.
390 For every library name @var{xxx} in @code{lib_LIBRARIES} or
391 @code{shared_LIBRARIES}, this variable contains a list of sources that
392 are needed to compile the library. OMK uses an extension of the
393 filename to determine the compiler to compile this source.
400 @node Header Files, , Libraries, Libraries
401 @subsection Header Files
403 C and C++ libraries are not very useful without header files. OMK
404 provides several variables that specify activities on header files.
406 During compilation, header files are copied (or linked) from source
407 directories to the @file{_compiled} tree
408 (see @ref{include-pass}). Libraries and programs are then compiled against
411 @anchor{include_HEADERS}
412 @defvar include_HEADERS
413 Specifies the list of header files to be exported for use by other
414 libraries/programs. The files are exported directly to the
415 @file{include} directory even if the file is located in a subdirectory
416 (like @file{sci_regs.h} in the example below)
419 include_HEADERS = regs.h periph/sci_regs.h
423 @defvar nobase_include_HEADERS
424 Similar to @ref{include_HEADERS}, but the directory prefix is always
425 kept. To include the file exported by this variable, use
426 @code{#include <@var{prefix}/@var{header.h}>}.
429 @defvar renamed_include_HEADERS
430 Exports the header files under different name. The form of the items
431 in this whitespace separated list is: @var{real name}@code{->}@var{new
435 renamed_include_HEADERS = orte_config_omk_win32.h->orte_config.h
440 If this variable equals to @samp{y}, symbolic links to headers in
441 source directories are used in @file{_compiled} tree instead of
444 Normally, the header files are copied into @file{_compiled} directory
445 to be prepared for transfer into target location afterwards. Copying
446 ensures that resulting libraries are in correspondence with the header
447 files even if the header is changed by a developer but the library is
450 @c Another reason for having single include directory for the whole
451 @c project is tat every component knows where to find header files of
454 On the other side, the copying could make problems during
455 development. Most @acronym{IDE}s, allows you to jump directly to the
456 place, where an error is reported by the compiler. If the error is in
457 a header file, IDE opens you the copy of the header file. If you
458 correct the error there, after the next compilation, your header file
459 will be overwritten by the old version from your source tree.
461 This option is not typically used in @file{Makefile.omk}, but in the
462 top level configuration file @file{config.omk} or on command line.
465 @node Multiple Directories, Dependency Tracking, Libraries, OMK User's Manual
466 @section Multiple Directories
468 OMK is probably most useful in projects consisting of multiple
469 directories. For such projects, it is not easy to write from scratch
470 classic Makefiles that provides all the needed features.
472 You can instruct OMK to descend to a (sub)directory by setting the
473 @code{SUBDIRS} variable in @file{Makefile.omk}.
476 This variable contains a list of directories, in which compilation
477 must be also invoked. Usually, names of subdirectories are used, but
478 you can use any path specification here.
480 Compilation is invoked in these directories before it is invoked in
481 the current directory.
483 @c TODO: Write tests for this.
485 @defvar ALL_OMK_SUBDIRS
486 This variable is set by OMK and can be used as the value of
487 @code{SUBDIRS} variable. It contains a list of all direct
488 subdirectories, which contain @file{Makefile.omk}. This is especially
489 useful if you are combining several projects or components
490 together. In the root directory of your project, you just create
491 symbolic links the components from other projects and all the linked
492 directories automatically appears as the value of this variable.
495 SUBDIRS = $(ALL_OMK_SUBDIRS)
499 @node Dependency Tracking, Configuration and Conditional Compilation, Multiple Directories, OMK User's Manual
500 @section Dependency Tracking
502 OMK automatically handles tracking of dependencies of files in compiled
503 projects. It uses gcc's @option{-M@var{x}} options to do this for object
504 files. This way, whenever you change some header file, OMK recompiles
505 only those files, where the changed header was really included.
507 Dependencies are also maintained for libraries and binaries. To find the
508 dependencies, OMK parses linker map files, so a change to some library
509 causes recompilation of all programs using that library.
511 @node Configuration and Conditional Compilation, Advanced OMK Features, Dependency Tracking, OMK User's Manual
512 @section Configuration and Conditional Compilation
514 In many projects, it is necessary to configure a compilation process. By
515 this configuring we mean, setting some parameters that influence the
516 output of compilation process. In GNU projects, @command{configure}
517 script is usually responsible for configuration. User provides some
518 parameters to @command{configure}, which is run before compilation, and
519 this script does all steps needed to configure the sources and
520 make-system in the desired way.
522 OMK has its own configuration mechanism, which is described in this
523 section. For future releases, we plan that this mechanism can make use
524 of GNU Autoconf, but currently there is no directly integrated support
527 In every directory you can specify some configuration parameters, which
528 can be modified by a user. Then, when @command{make default-config} is
529 run, all these parameters are found and together with their default
530 values are stored as makefile variables in
531 @file{config.omk-default}. This file is included during compilation, so
532 if you don't specify other values, these defaults are used. If you are
533 not satisfied with these defaults, you can override the values of
534 parameters in @file{config.omk}. This file is also included during
535 compilation and variables mentioned there takes precedence over those
536 specified in @file{config.omk-default}. Both @file{config.omk} and
537 @file{config.omk-default} have to be stored in the same directory as
538 @file{Makefile.rules}.
540 Besides overriding the default values of configuration parameters,
541 @file{config.omk} can also be used as a common place to store some
542 global settings that applies to the whole project, e.g. the compiler to
543 use or common compiler flags.
545 @subsection Specifying Configuration Parameters
547 To specify names and default values of configuration parameters use the
548 @code{default_CONFIG} variable in @file{Makefile.omk}.
550 @defvar default_CONFIG
551 This variable contains a list of configuration parameters and their
552 default values. The format of every item in this list is
553 @var{CONFIG_xxxx}=@var{value}. You can name the parameter as you want,
554 but it is good practice to start the name with @samp{CONFIG_} prefix.
556 OMK can automatically generate header files, with C preprocessor macro
557 definitions according to the OMK's configuration parameters. The
558 actual content of generated header files depends on the form of the
559 @var{value}. The possible forms are:
562 @item @samp{y}, @samp{n} or @samp{x}
563 This defines boolean parameters. If the value of the parameter is
564 @samp{y}, the @samp{#define CONFIG_@var{xxx} 1} is generated, if it is
565 @samp{n}, no @code{#define} is generated.
567 @samp{x} is a special value called @emph{recessive 'n'}. The meaning
568 is that this parameter influences the component in the current
569 directory (i.e. the corresponding @code{#define} will be included in
570 @code{LOCAL_CONFIG_H}; see @ref{LOCAL_CONFIG_H}) but the default value
571 is not specified here. If the default value is not specified anywhere,
572 the behavior is the same as if @samp{n} is specified.
574 Numeric parameters. The define looks like @samp{#define CONFIG_@var{xxx} @var{number}}
576 Text without quotes. The define looks like @samp{#define CONFIG_@var{xxx} @var{text}}
578 Text with quotes. The define looks like @samp{#define CONFIG_@var{xxx} "@var{text}"}
582 @noindent Example of using @code{default_CONFIG}. @file{Makefile.omk} reads like:
584 @verbatiminclude ../tests/config/default/Makefile.omk
586 @noindent and @file{subdir/Makefile.omk} like:
588 @verbatiminclude ../tests/config/default/subdir/Makefile.omk
591 @noindent After running @command{make default-config}, the content of
592 @file{config.omk-default} will be:
594 @verbatiminclude ../tests/config/default/config.omk-correct
597 @subsection Using Configuration Parameters
599 Configuration parameters can be used in two ways:
602 as variables in @file{Makefile.omk} and
604 as C/C++ preprocessor macros in OMK generated header files.
607 @noindent For the first use, your @file{Makefile.omk} may contain something like:
609 SUBDIRS = arch/$(CONFIG_ARCH)
611 ifeq ($(CONFIG_DEBUG),y)
612 DEFS += -DUSE_SIMULATOR
616 @noindent For the second use, there are several variables that control
617 the generation of header files with configuration values. These
618 variables are described here:
620 @anchor{LOCAL_CONFIG_H}
621 @defvar LOCAL_CONFIG_H
622 The value of this variable is the name of a header file, which will
623 contain all configuration parameters declared in the current directory
624 by @code{default_CONFIG}. This header file is accessible only by files
625 in the current directory and it should be included like @code{#include
628 In @file{Makefile.omk}, the use of this variable can look like this:
631 LOCAL_CONFIG_H = myconfig.h
635 @defvar config_include_HEADERS
636 This variable is similar to @code{LOCAL_CONFIG_H}. One difference is
637 that the generated header file is accessible to all sub-projects in
638 all directories, not only to the files in the same directory (the
639 header is stored in @file{_compiled} tree). The second difference is
640 that you have to specify, which configuration parameters you want to
641 appear in the header file.
645 This variable determines the configuration parameters that should be
646 stored in a header file specified by
647 @code{config_include_HEADERS}. The @var{xxx} in the name of this
648 variable needs to be the same as the base name (without extension) of
652 @noindent Example of using @code{config_include_HEADERS}:
654 default_CONFIG = CONFIG_LINCAN=y CONFIG_LINCANRTL=n CONFIG_LINCANVME=n
655 config_include_HEADERS = global.h
656 global_DEFINES = CONFIG_OC_LINCAN CONFIG_OC_LINCANRTL
659 @noindent Here, we include only two out of the three configuration
660 parameters defined in the current @file{Makefile.omk}. It is also
661 possible to include configuration parameters defined in a different
664 @subsection Common Variables
666 It is common practice to use @file{config.omk} to store project-wide
667 settings. Here is the list of variables, which are commonly set here
668 (but they can also be set elsewhere, e.g. in @file{Makefile.omk}).
670 You can easily ``reconfigure'' your project by changing the
671 @file{config.omk} file. It is useful to have several configurations
672 stored in different files and let @file{config.omk} be a symbolic link
673 to the desired configuration.
677 The name of C compiler.
679 Command line options for C compiler.
681 The name of C++ compiler.
683 Additional parameters (besides @code{CFLAGS}) to by passed to C++
687 @node Advanced OMK Features, Running OMK under Windows OS, Configuration and Conditional Compilation, OMK User's Manual
688 @section Advanced OMK Features
690 In this section we list several OMK features, which are more complicated
691 or rarely used so they were omitted in previous sections.
695 The @file{_compiled} directory can be shared between multiple projects
696 (by using symbolic links).
699 If you work on a bigger project, you usually don't need to rebuild the
700 whole project and call @command{make} only in a
701 subdirectory. Sometimes, it might be useful to rebuild the whole
702 project. You can either change working directory to the root of your
703 project and call @command{make} there or, as a shortcut, you can use
704 @code{W} variable (see @ref{W}) to compile everything directly from a
711 Searching for @file{Makefile.rules} works such way, that if you get
712 into sources directory over symbolic links, OMK is able to unwind your
713 steps back. This implies you can make links to component directories
714 on read-only media, copy @file{Makefile.rules}, @file{Makefile} and
715 top-level @file{Makefile.omk}, adjust @file{Makefile.omk} to contain
716 only required components and then call @command{make} in the top
717 directory or even in read-only directories after changing working
718 directory from your tree to readonly media.
724 If this variable equals to @samp{1}, the @b{whole} project is
725 (re)compiled, even if @command{make} is called from a subdirectory.
731 @node Running OMK under Windows OS, Interfacing OMK to popular IDEs, Advanced OMK Features, OMK User's Manual
732 @section Running OMK under Windows OS
734 @node Interfacing OMK to popular IDEs, Troubleshooting, Running OMK under Windows OS, OMK User's Manual
735 @section Interfacing OMK to popular IDEs
739 KDevelop has support for custom build systems. To use KDevelop to
740 develop projects using OMK follow these steps. These steps are valid for
741 version 3.5.0 of KDevelop, but for previous versions it doesn't differ
746 Import project to KDevelop (from menu choose @emph{Project---Import
747 existing project}). Select the type of project to @emph{Generic C
748 Application (Custom Buildsystem)}.
754 Then answer to following dialogs as you want.
759 @image{kdevelop3} @image{kdevelop4}
763 If you are working only on some small part of the bigger project, you
764 usually don't want to recompile the whole project every time. In
765 @emph{Project---Project Options}, you can specify the subdirectory where to
772 If you want to switch between several configurations easily (see also
773 @ref{Configuration and Conditional Compilation}), in the same dialog
774 you can add @option{-e} to make options. This makes environment variables
775 have higher precedence than those in @file{config.omk-default}. Then,
776 you can define several environments with different
777 @code{CONFIG_@var{xxx}} variables and their values.
783 You can easily switch the configurations from @emph{Build---Make
793 @subsection Emacs, VIM, etc.
795 Since OMK compilation is started by executing @command{make} command,
796 many common editors can work easily with OMK.
798 Under Emacs, you can use @command{compile} or @command{recompile}
799 commands as you are used to do.
801 @node Troubleshooting, , Interfacing OMK to popular IDEs, OMK User's Manual
802 @section Troubleshooting
804 Renaming of some file => dependency problems.
806 Manual compilation ... V=1
808 @node Original README, OMK Development, OMK User's Manual, Top
809 @chapter Original README
811 Since this manual still doesn't cover all aspects of OMK, we include
812 here a @file{README.rules} file, which was written for the first version
815 @b{Important notice:} This make system uses features found in recent
816 versions of GNU Make program. If you encounter problems with package
817 building, check, that you use correct version of Make program. The
818 Make older than version 3.80, could not be used. Even Make version
819 3.80 has annoying bug which causes building fail with misleading
820 message "virtual memory exhausted". Please, upgrade at least to
821 version 3.81 of GNU Make.
823 There is list of features which we want to solve with our make system:
826 Central @file{Makefile.rules} for most of components of a bigger project.
828 FIXME (our CAN framework includes more libraries common with our other
829 projects, we need to separate some utility libraries etc.)
831 The rules in more spread Makefiles are way to the hell (update for
832 different kernel, RT-Linux etc would be nightmare in other case).
834 Make system should allow to freely move cross-dependant components in
835 directory structure without need to update users of moved component (I
836 hate somethink like @option{-I../../sched/rtlshwq/include} in CAN makefiles for
837 example. If a component is renamed or version is added to then name,
838 all Makefiles in CAN will require update).
840 Make system should be able to compile mutually cross-dependant
841 libraries and should ensure, that change in one component sources or
842 headers would result in relink or rebuild in components linked against
843 that library or including modified header file.
845 Make system has to enable compilation out of OCERA full source tree
846 (we would lost many users of particular components in other case).
848 Compile should be able to do all above work without need to install
849 any files before successful finish of build.
851 Because we use some libraries for RT-Linux build and user-space build,
852 we need to solve how to compile from same sources to both targets.
854 The build system should allow to call make for particular source
855 subdirectory. Time of recursive make through all subdirectories is
858 Make system should enable to build out of sources tree (else clean or
859 working with CVS sandbox gets fussy and simultaneous multiple targets
862 It would be good, if there is a possibility to call make from
863 read-only media sources.
865 Make system should store results of build in some separate directory
866 structure to simple install and testing.
868 Makefiles in sources directories should be simple.
871 There is probably only one alternative fully supporting above requirements
872 and it is GNU Autoheader...Automake...Autoconf... system.
873 But it is complicated and requires big amount of support files.
874 It would be acceptable if it could be easily used for OCERA framework.
875 But there are important show stoppers for that system:
878 It would require deep revision of all OCERA CVS contents and agreement
879 on this would be problematic
881 This system is not well prepared for dual compilation for Linux and
882 RT-Linux sub-targets. It would mean many changes in default autoconf
883 setup to support this. Probably simplest way would be to rebuild GCC
884 tool chain for something like i586-elf-rtlinux. This would require
885 even more space for OCERA development.
888 The problem calls for some solution, which would have minimal impact
889 on other components and would be elegant and would be maintainable
890 and small, because our main goal is components development and not
891 make systems development.
893 There is result of our trial. It is OMK make system.
894 The @file{Makefile} and @file{Makefile.omk} files should be in all source
895 directories. Common @file{Makefile.rules} file is required in the toplevel
896 sources directory. Alternatively this file could be moved
897 to link tree pointing into readonly media or can be anywhere
898 else if @code{MAKERULES_DIR} and @code{SOURCES_DIR} are specified.
900 @c !!! tohle tam nejak zmizelo, mozna by to chtelo skontrolovat, ze to
901 @c sedi s aktualnim stavem
904 Syntax of Makefile.omk files is for usual cases compatible
905 to Automake's Makefile.am descriptions. There are specific targets
906 for RT-Linux and Linux kernel related stuff
908 Makefile.omk user defined variables
911 list of subdirectories intended for make from actual directory
913 list of the user-space libraries
914 @item shared_LIBRARIES
915 list of the user-space shared libraries
916 @item kernel_LIBRARIES
917 list of the kernel-space libraries
918 @item rtlinux_LIBRARIES
919 list of the RT-Linux kernel-space libraries
920 @item include_HEADERS
921 list of the user-space header files
922 @item nobase_include_HEADERS
923 headers copied even with directory part
925 list of the kernel-space header files
926 @item rtlinux_HEADERS
927 list of the RT-Linux kernel-space header files
929 list of the require binary programs
931 list of the development utility programs
933 list of the kernel side modules/applications
934 @item rtlinux_MODULES
935 list of RT-Linux the kernel side modules/applications
937 list of specific target sources
939 additional include directories and defines for user-space
940 @item kernel_INCLUDES
941 additional include directories and defines for kernel-space
942 @item rtlinux_INCLUDES
943 additional include directories and defines for RT-Linux
945 list of default config assignments CONFIG_XXX=y/n ...
948 The Makefile is same for all sources directories and is only 14 lines
949 long. It is there only for convenience reasons to enable call "make"
950 from local directory. It contains code which locates
951 @file{Makefile.rules} in actual or any parent directory. With standard
952 BASH environment it works such way, that if you get into sources
953 directory over symbolic links, it is able to unwind yours steps back
954 => you can make links to readonly media component directories, copy
955 @file{Makefile.rules}, Makefile and toplevel Makefile.omk, adjust
956 Makefile.omk to contain only required components and then call make in
957 top or even directories after crossing from your tree to readonly
960 The system compiles all files out of source directories. The actual
961 version of system is adapted even for OCERA tree mode if
962 @code{OCERA_DIR} variable is defined in @file{Makefile.rules}
964 There are next predefined directory name components, which can be
968 @item BUILD_DIR_NAME = _build
969 prefix of directory, where temporary build files are stored
970 @item COMPILED_DIR_NAME = _compiled
971 prefix of directory, where final compilation results are stored
972 @item GROUP_DIR_NAME = yyy
973 this is used for separation of build sub-trees in OCERA environment
974 where more @file{Makefile.rules} is spread in the tree
977 Next directories are used:
980 @item KERN_BUILD_DIR := $(MAKERULES_DIR)/$(BUILD_DIR_NAME)/kern
981 directory to store intermediate files for kernel-space targets
982 @item USER_BUILD_DIR := $(MAKERULES_DIR)/$(BUILD_DIR_NAME)/user
983 directory to store intermediate files for user-space targets
985 @item USER_INCLUDE_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/include
986 directory to store exported include files which should be installed later
987 on user-space include path
988 @item USER_LIB_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/lib
989 same for user-pace libraries
990 @item USER_UTILS_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/bin-utils
991 utilities for testing, which would not probably be installed
992 @item USER_BIN_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/bin
993 binaries, which should go into directory on standard system PATH
994 (/usr/local/bin, /usr/bin or $(prefix)/bin)
996 @item KERN_INCLUDE_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/include-kern
997 directory to store exported include files which should be installed later
998 on kernel-space include path
999 @item KERN_LIB_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/lib-kern
1000 same for kernel-pace libraries
1001 @item KERN_MODULES_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/modules
1002 builded modules for Linux kernel or RT-Linux system
1005 There is more recursive passes through directories to enable
1006 mutual dependant libraries and binaries to compile.
1007 Next passes are defined
1010 @item default-config
1011 generates @file{config.omk-default} or xxx-default (FIXME) configuration file
1013 checks and creates required build directories
1015 copies header files to @code{USER_INCLUDE_DIR} and @code{KERN_INCLUDE_DIR}
1017 builds objects in USER_BUILD_DIR/@var{relative path} and creates libraries
1019 @item binary-pass and utils-pass
1020 links respective binaries in USER_@{BIN,UTILS@}_DIR directory. If some
1021 object file is missing it compiles it in USER_BUILD_DIR/@var{relative path}
1022 @item kernel-lib-pass
1023 builds libraries for kernel space targets
1025 builds kernel modules
1028 The amount of passes is relatively high and consumes some time. But
1029 only other way to support all required features is to assemble one big
1030 toplevel Makefile, which would contain all components and targets
1033 Drawbacks of designed make system
1036 the system is not as fast as we would like
1038 it lacks Autoconf and configure extensive support for many systems
1039 from UNIX to DOS and WINDOWS
1041 it does not contain support for checking existence of target
1042 libraries and functionalities as GNU Autoconf
1044 it is heavily dependant on GNU MAKE program. But it would not be big
1045 problem, because even many commercial applications distribute GNU MAKE
1046 with them to be able to work in non-friendly systems
1048 the key drawback is dependence on recent MAKE version 3.80 and better
1049 and even version 3.80 of MAKE has important bug, which has been
1050 corrected in newer sources (FIXME)
1053 The last point is critical. I have not noticed it first, because
1054 I use Slackware-9.2 and it contains latest released version
1055 of MAKE (version 3.80).
1056 The problem appears when I have tried to build bigger libraries.
1057 There is bug in version 3.80, which results in misleading
1058 error "Virtual memory exhausted". It is known bug with ID 1517
1061 * long prerequisite inside eval(call()) => vm exhausted, Paul D. Smith
1065 I have optimized some rules to not push memory to the edge,
1066 but there could be still issues with 3.80 version.
1068 I have downloaded latest MAKE CVS sources. The compilation required
1069 separate lookup and download for .po files and full Autoheader... cycle.
1070 I have put together package similar to release. Only ./configure --prefix=...
1071 and make is required. CVS sources contains version 3.81beta1.
1072 You can download prepared sources archive from
1073 @indicateurl{http://paulandlesley.org/make/make-3.81beta1.tar.bz2}
1074 Or you can get our local copy from
1075 @indicateurl{http://cmp.felk.cvut.cz/~pisa/can/make-3.81beta1.tar.gz}
1077 The archive contains even "make" binary build by me, which should work
1078 on other Linux distributions as well. Older version of MAKE (3.79.x
1079 released about year 2000) found on Mandrake and RedHat are not
1080 sufficient and do not support eval feature. I do not expect, that
1081 Debian would be more up-to-date or contain fixes to MAKE vm exhausted
1084 The local CTU archive with our CAN components prepared for inclusion
1085 into OCERA SF CVS could be found in my "can" directory
1087 @indicateurl{http://cmp.felk.cvut.cz/~pisa/can/ocera-can-031212.tar.gz}
1089 The code should build for user-space with new make on most of Linux distros
1090 when make is updated.
1092 If you want to test compile for RT-Linux targets, line
1095 #RTL_DIR := /home/cvs/ocera/ocera-build/kernel/rtlinux
1098 in @file{Makefile.rules} has to be activated and updated
1099 to point RT-Linux directory containing "rtl.mk".
1100 There is only one library ("ulutrtl") and test utility compiled for RT-Linux
1101 (@file{can/utils/ulut/ul_rtlchk.c}).
1103 The next line, if enabled, controls compilation in OCERA project tree
1106 #OCERA_DIR := $(shell ( cd -L $(MAKERULES_DIR)/../../.. ; pwd -L ) )
1109 The LinCAN driver has been updated to compile out of source directories.
1111 Please, check, if you could compile CAN package and help us with integration
1112 into OCERA SF CVS. Send your comments and objections.
1114 The OMK system has been adapted to support actual OCERA configuration process.
1115 I am not happy with ocera.mk mix of defines and poor two or three rules,
1116 but OMK is able to overcome that.
1118 The OMK system has integrated rules (default-config) to build default
1119 configuration file. The file is named @file{config.omk-default} for
1120 the stand-alone compilation. The name corresponds to OCERA config +
1121 "-default" if OCERA_DIR is defined. This file contains statements
1122 from all @code{default_CONFIG} lines in all @file{Makefile.omk}. The
1123 file should be used for building of own @file{config.omk} file, or as
1124 list for all options if Kconfig is used.
1126 @c @chapter OMK Reference
1128 @node OMK Development, Variable Index, Original README, Top
1129 @chapter OMK Development
1133 @node Variable Index, , OMK Development, Top
1134 @unnumbered Variable Index
1138 @c @node Concept Index, , Variable Index, Top
1139 @c @unnumbered Concept Index