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 * Properties of Specific Makefile.rules::
173 * Running OMK under Windows OS::
174 * Interfacing OMK to popular IDEs::
178 @node Basic Concepts, Invoking OMK, OMK User's Manual, OMK User's Manual
179 @section Basic Concepts
181 The main concept of OMK is very simple. In the root directory of the
182 projects resides a file called @file{Makefile.rules}. This file contains
183 all compilation rules needed for compilation of a particular
184 project. There are different @file{Makefile.rules} for different
185 platforms (Unix, RTEMS, system-less, ...). In every subdirectory a
186 @file{Makefile.omk} is stored. This file determines what should be done
187 in the respective directory (e.g. compile a program from several source
188 files). Its syntax is very simple -- see the following sections.
190 Since make searches by default for a @file{Makefile} and not for
191 @file{Makefile.rules} or @file{Makefile.omk}, there must be a small
192 generic @file{Makefile} in every directory, whose task is only to find
193 @file{Makefile.rules} in the actual or any parent directory and include
194 it. This search is performed only once at the beginning of compilation.
196 @c TODO: Pavel's note about qmake.
198 The compilation process itself is comprised of several passes. Every
199 pass traverses the whole directory structure@footnote{In future, we are
200 planning some optimization that allows OMK to traverse the directories
201 only once and thus decrease compilation time.} and does a particular
202 task in every directory of the project. Typically, these passes are:
204 @anchor{include-pass}
206 This pass takes all include files marked for ``export'' and copies
207 (or links) them to the @file{include} directory under
208 @file{_compiled} directory. @xref{Header Files}.
210 Also, during this pass, automatically generated header file are
211 generated according to the current
212 configuration. @xref{Configuration and Conditional Compilation}.
214 During this pass, all include files are in place, so all libraries
217 Finally, programs can be compiled and linked against libraries
218 created in the previous pass.
221 The results of compilation are stored under the @file{_compiled}
222 directory. This directory is structured as a classical Unix file-system
223 (it contains directories like @file{bin}, @file{lib} and @file{include})
224 and can be directly copied to the target device or to some directory on
225 a host computer (e.g. @file{/usr/local}).
227 Besides @file{_compiled} directory, there in a @file{_build}
228 directory. Under this directory are stored some temporary files and
229 intermediate compilation products (object files, dependency files etc.).
231 In the next section, we provide an overview of methods, how to invoke
232 OMK from command line. Section @ref{Interfacing OMK to popular IDEs}
233 covers running of OMK from popular IDEs.
235 Sections @ref{Compiling Programs} through @ref{Configuration and
236 Conditional Compilation} deals with the content of
237 @file{Makefile.omk}. Its syntax in usual cases compatible to GNU
238 Automake's @file{Makefile.am} syntax. Also, the scheme for naming
239 variables was inspired by Automake so most OMK variables have the name
240 like @samp{@var{target}_@var{TYPE}}.
242 @node Invoking OMK, Compiling Programs, Basic Concepts, OMK User's Manual
243 @section Invoking OMK
245 Before using OMK for the first time, you have to call:
247 @command{make default-config}
249 @noindent See @ref{Configuration and Conditional Compilation} for
250 details. If you forget to do this, OMK will notice you.
252 To compile the whole project or only some subtree of the project, call
256 @noindent in the appropriate directory.
258 To clean files in @file{_build} directory but not in @file{_compiled}
264 To clean the compilation completely, you can either remove
265 @file{_compiled} and @file{_build} directories manually, or call
267 @command{make distclean}
269 @noindent which does the same. This command removes these directories
270 even if you call it from a subdirectory.
272 To debug compilation problems, you can use @code{V} variable (see
278 You can also set values of some other variables on command line for
279 temporary change something. The example below compiles the code
280 temporarily with debugging information:
282 @command{make CFLAGS="-g -O0 -Wall"}
285 If your project uses an alternative make-system (e.g. Automake or custom
286 makefiles), it might be useful for you to use the command:
288 @command{make omkize}
290 @noindent This will find all @file{Makefile.omk} files in all subdirectories
291 and copies generic @file{Makefile} from the root directory to that
292 subdirectories. This way you can easily switch your project to use OMK.
298 If this variable equals to @samp{1}, the whole command lines for all
299 executed commands are displayed. When not set or zero, only short
300 messages are printed. Value of @samp{2} displays the whole command lines
301 as with @samp{1} and in addition directory navigation messages are
305 @node Compiling Programs, Libraries, Invoking OMK, OMK User's Manual
306 @section Compiling Programs
308 To tell OMK to compile a program, you need to set some variables in
309 @file{Makefile.omk} (usually) in the directory where program sources are
312 In the example bellow a program @command{test} will be compiled from
313 source @file{test.c}.
316 @verbatiminclude ../tests/programs/Makefile.omk
319 @noindent The variables are:
321 @anchor{bin_PROGRAMS}
323 Contains a list of names (whitespace separated) of programs to be
324 compiled in this directory.
327 @defvar test_PROGRAMS
328 Almost the same as @ref{bin_PROGRAMS}, but resulting binaries are
329 stored in @file{bin-tests} directory instead of @file{bin}. This
330 variable is intended for various test programs not to be mixed with
334 @defvar utils_PROGRAMS
335 Almost the same as @ref{bin_PROGRAMS}, but resulting binaries are
336 stored in @file{bin-utils} directory instead of @file{bin}. This
337 variable is intended for various development utilities not to be mixed
338 with the final product.
342 For every program name @var{xxx} in @code{bin_PROGRAMS},
343 @code{test_PROGRAMS} or @code{utils_PROGRAMS}, this variable contains
344 a list of sources that are needed to compile the program. OMK uses an
345 extension of the filename to determine the compiler to compile this
350 This variable contains a list of libraries the program @var{xxx} will
359 This variable contains a list of libraries all programs in this
360 directory needs to be linked to.
364 Directives passed to the C or C++ compiler with additional directories
365 to be searched for header files. In most cases you need to specify an
366 absolute path. To specify a directory relative to the source
367 directory, you can use the @code{$(SOURCES_DIR)} variable, which
368 refers to the directory, where @file{Makefile.omk} is located. This
369 variable applies to all compilations invoked in the current directory.
372 INCLUDES = -I$(SOURCES_DIR)/my_include_dir
377 Directives passed to the C or C++ compiler with preprocessor macro
378 definitions. This variable applies to all compilations invoked in the
387 @c FIXME: INCLUDES variable should not be set by rtlinux rules.
389 @node Libraries, Multiple Directories, Compiling Programs, OMK User's Manual
393 With OMK, you can easily create statically or dynamically linked
394 libraries. The way of creating libraries is very similar to how programs
395 are created. @xref{Compiling Programs}.
397 In @file{Makefile.omk}, you specify several variables, which defines how
398 the libraries should be compiled. In the example below the library
399 @samp{mylib} is created from two sources @file{funca.c} and
400 @file{funcb.c}. Interface of this library is defined in
401 @file{myfunc.h}. Therfore, we export this header for use by other
405 @verbatiminclude ../tests/libraries/Makefile.omk
408 @noindent Variables for use with libraries are:
410 @defvar lib_LIBRARIES
411 Specifies a list of statically linked libraries to be compiled.
414 @defvar shared_LIBRARIES
415 Specifies a list of dynamically linked libraries to be compiled.
419 For every library name @var{xxx} in @code{lib_LIBRARIES} or
420 @code{shared_LIBRARIES}, this variable contains a list of sources that
421 are needed to compile the library. OMK uses an extension of the
422 filename to determine the compiler to compile this source.
429 @node Header Files, , Libraries, Libraries
430 @subsection Header Files
432 C and C++ libraries are not very useful without header files. OMK
433 provides several variables that specify activities on header files.
435 During compilation, header files are copied (or linked) from source
436 directories to the @file{_compiled} tree
437 (see @ref{include-pass}). Libraries and programs are then compiled against
440 @anchor{include_HEADERS}
441 @defvar include_HEADERS
442 Specifies the list of header files to be exported for use by other
443 libraries/programs. The files are exported directly to the
444 @file{include} directory even if the file is located in a subdirectory
445 (like @file{sci_regs.h} in the example below)
448 include_HEADERS = regs.h periph/sci_regs.h
452 @defvar nobase_include_HEADERS
453 Similar to @ref{include_HEADERS}, but the directory prefix is always
454 kept. To include the file exported by this variable, use
455 @code{#include <@var{prefix}/@var{header.h}>}.
458 @defvar renamed_include_HEADERS
459 Exports the header files under different name. The form of the items
460 in this whitespace separated list is: @var{real name}@code{->}@var{new
464 renamed_include_HEADERS = orte_config_omk_win32.h->orte_config.h
469 If this variable equals to @samp{y}, symbolic links to headers in
470 source directories are used in @file{_compiled} tree instead of
473 Normally, the header files are copied into @file{_compiled} directory
474 to be prepared for transfer into target location afterwards. Copying
475 ensures that resulting libraries are in correspondence with the header
476 files even if the header is changed by a developer but the library is
479 @c Another reason for having single include directory for the whole
480 @c project is tat every component knows where to find header files of
483 On the other side, the copying could make problems during
484 development. Most @acronym{IDE}s, allows you to jump directly to the
485 place, where an error is reported by the compiler. If the error is in
486 a header file, IDE opens you the copy of the header file. If you
487 correct the error there, after the next compilation, your header file
488 will be overwritten by the old version from your source tree.
490 This option is not typically used in @file{Makefile.omk}, but in the
491 top level configuration file @file{config.omk} or on command line.
494 @node Multiple Directories, Dependency Tracking, Libraries, OMK User's Manual
495 @section Multiple Directories
497 OMK is probably most useful in projects consisting of multiple
498 directories. For such projects, it is not easy to write from scratch
499 classic Makefiles that provides all the needed features.
501 You can instruct OMK to descend to a (sub)directory by setting the
502 @code{SUBDIRS} variable in @file{Makefile.omk}.
505 This variable contains a list of directories, in which compilation
506 must be also invoked. Usually, names of subdirectories are used, but
507 you can use any path specification here.
509 Compilation is invoked in these directories before it is invoked in
510 the current directory.
512 @c TODO: Write tests for this.
514 @defvar ALL_OMK_SUBDIRS
515 This variable is set by OMK and can be used as the value of
516 @code{SUBDIRS} variable. It contains a list of all direct
517 subdirectories, which contain @file{Makefile.omk}. This is especially
518 useful if you are combining several projects or components
519 together. In the root directory of your project, you just create
520 symbolic links the components from other projects and all the linked
521 directories automatically appears as the value of this variable.
524 SUBDIRS = $(ALL_OMK_SUBDIRS)
528 @node Dependency Tracking, Configuration and Conditional Compilation, Multiple Directories, OMK User's Manual
529 @section Dependency Tracking
531 OMK automatically handles tracking of dependencies of files in compiled
532 projects. It uses gcc's @option{-M@var{x}} options to do this for object
533 files. This way, whenever you change some header file, OMK recompiles
534 only those files, where the changed header was really included.
536 Dependencies are also maintained for libraries and binaries. To find the
537 dependencies, OMK parses linker map files, so a change to some library
538 causes recompilation of all programs using that library.
540 @node Configuration and Conditional Compilation, Advanced OMK Features, Dependency Tracking, OMK User's Manual
541 @section Configuration and Conditional Compilation
543 In many projects, it is necessary to configure a compilation process. By
544 this configuring we mean, setting some parameters that influence the
545 output of compilation process. In GNU projects, @command{configure}
546 script is usually responsible for configuration. User provides some
547 parameters to @command{configure}, which is run before compilation, and
548 this script does all steps needed to configure the sources and
549 make-system in the desired way.
551 OMK has its own configuration mechanism, which is described in this
552 section. For future releases, we plan that this mechanism can make use
553 of GNU Autoconf, but currently there is no directly integrated support
556 In every directory you can specify some configuration parameters, which
557 can be modified by a user. Then, when @command{make default-config} is
558 run, all these parameters are found and together with their default
559 values are stored as makefile variables in
560 @file{config.omk-default}. This file is included during compilation, so
561 if you don't specify other values, these defaults are used. If you are
562 not satisfied with these defaults, you can override the values of
563 parameters in @file{config.omk}. This file is also included during
564 compilation and variables mentioned there takes precedence over those
565 specified in @file{config.omk-default}. Both @file{config.omk} and
566 @file{config.omk-default} have to be stored in the same directory as
567 @file{Makefile.rules}.
569 Besides overriding the default values of configuration parameters,
570 @file{config.omk} can also be used as a common place to store some
571 global settings that applies to the whole project, e.g. the compiler to
572 use or common compiler flags.
574 @subsection Specifying Configuration Parameters
576 To specify names and default values of configuration parameters use the
577 @code{default_CONFIG} variable in @file{Makefile.omk}.
579 @defvar default_CONFIG
580 This variable contains a list of configuration parameters and their
581 default values. The format of every item in this list is
582 @var{CONFIG_xxxx}=@var{value}. You can name the parameter as you want,
583 but it is good practice to start the name with @samp{CONFIG_} prefix.
585 OMK can automatically generate header files, with C preprocessor macro
586 definitions according to the OMK's configuration parameters. The
587 actual content of generated header files depends on the form of the
588 @var{value}. The possible forms are:
591 @item @samp{y}, @samp{n} or @samp{x}
592 This defines boolean parameters. If the value of the parameter is
593 @samp{y}, the @samp{#define CONFIG_@var{xxx} 1} is generated, if it is
594 @samp{n}, no @code{#define} is generated.
596 @samp{x} is a special value called @emph{recessive 'n'}. The meaning
597 is that this parameter influences the component in the current
598 directory (i.e. the corresponding @code{#define} will be included in
599 @code{LOCAL_CONFIG_H}; see @ref{LOCAL_CONFIG_H}) but the default value
600 is not specified here. If the default value is not specified anywhere,
601 the behavior is the same as if @samp{n} is specified.
603 Numeric parameters. The define looks like @samp{#define CONFIG_@var{xxx} @var{number}}
605 Text without quotes. The define looks like @samp{#define CONFIG_@var{xxx} @var{text}}
607 Text with quotes. The define looks like @samp{#define CONFIG_@var{xxx} "@var{text}"}
611 @noindent Example of using @code{default_CONFIG}. @file{Makefile.omk} reads like:
613 @verbatiminclude ../tests/config/default/Makefile.omk
615 @noindent and @file{subdir/Makefile.omk} like:
617 @verbatiminclude ../tests/config/default/subdir/Makefile.omk
620 @noindent After running @command{make default-config}, the content of
621 @file{config.omk-default} will be:
623 @verbatiminclude ../tests/config/default/config.omk-correct
626 @subsection Using Configuration Parameters
628 Configuration parameters can be used in two ways:
631 as variables in @file{Makefile.omk} and
633 as C/C++ preprocessor macros in OMK generated header files.
636 @noindent For the first use, your @file{Makefile.omk} may contain something like:
638 SUBDIRS = arch/$(CONFIG_ARCH)
640 ifeq ($(CONFIG_DEBUG),y)
641 DEFS += -DUSE_SIMULATOR
645 @noindent For the second use, there are several variables that control
646 the generation of header files with configuration values. These
647 variables are described here:
649 @anchor{LOCAL_CONFIG_H}
650 @defvar LOCAL_CONFIG_H
651 The value of this variable is the name of a header file, which will
652 contain all configuration parameters declared in the current directory
653 by @code{default_CONFIG}. This header file is accessible only by files
654 in the current directory and it should be included like @code{#include
657 In @file{Makefile.omk}, the use of this variable can look like this:
660 LOCAL_CONFIG_H = myconfig.h
664 @defvar config_include_HEADERS
665 This variable is similar to @code{LOCAL_CONFIG_H}. One difference is
666 that the generated header file is accessible to all sub-projects in
667 all directories, not only to the files in the same directory (the
668 header is stored in @file{_compiled} tree). The second difference is
669 that you have to specify, which configuration parameters you want to
670 appear in the header file.
674 This variable determines the configuration parameters that should be
675 stored in a header file specified by
676 @code{config_include_HEADERS}. The @var{xxx} in the name of this
677 variable needs to be the same as the base name (without extension) of
681 @noindent Example of using @code{config_include_HEADERS}:
683 default_CONFIG = CONFIG_LINCAN=y CONFIG_LINCANRTL=n CONFIG_LINCANVME=n
684 config_include_HEADERS = global.h
685 global_DEFINES = CONFIG_OC_LINCAN CONFIG_OC_LINCANRTL
688 @noindent Here, we include only two out of the three configuration
689 parameters defined in the current @file{Makefile.omk}. It is also
690 possible to include configuration parameters defined in a different
693 @subsection Common Variables
695 It is common practice to use @file{config.omk} to store project-wide
696 settings. Here is the list of variables, which are commonly set here
697 (but they can also be set elsewhere, e.g. in @file{Makefile.omk}).
699 You can easily ``reconfigure'' your project by changing the
700 @file{config.omk} file. It is useful to have several configurations
701 stored in different files and let @file{config.omk} be a symbolic link
702 to the desired configuration.
706 The name of C compiler.
708 Command line options for C compiler.
710 The name of C++ compiler.
712 Additional parameters (besides @code{CFLAGS}) to by passed to C++
716 @node Advanced OMK Features, Properties of Specific Makefile.rules, Configuration and Conditional Compilation, OMK User's Manual
717 @section Advanced OMK Features
719 In this section we list several OMK features, which are more complicated
720 or rarely used so they were omitted in previous sections.
724 The @file{_compiled} directory can be shared between multiple projects
725 (by using symbolic links).
728 If you work on a bigger project, you usually don't need to rebuild the
729 whole project and call @command{make} only in a
730 subdirectory. Sometimes, it might be useful to rebuild the whole
731 project. You can either change working directory to the root of your
732 project and call @command{make} there or, as a shortcut, you can use
733 @code{W} variable (see @ref{W}) to compile everything directly from a
740 Searching for @file{Makefile.rules} works such way, that if you get
741 into sources directory over symbolic links, OMK is able to unwind your
742 steps back. This implies you can make links to component directories
743 on read-only media, copy @file{Makefile.rules}, @file{Makefile} and
744 top-level @file{Makefile.omk}, adjust @file{Makefile.omk} to contain
745 only required components and then call @command{make} in the top
746 directory or even in read-only directories after changing working
747 directory from your tree to readonly media.
753 If this variable equals to @samp{1}, the @b{whole} project is
754 (re)compiled, even if @command{make} is called from a subdirectory.
758 @node Properties of Specific Makefile.rules, Running OMK under Windows OS, Advanced OMK Features, OMK User's Manual
759 @section Properties of Specific Makefile.rules
761 In previous sections, general properties of @file{Makefile.rules} were
762 documented. This section contains documentation to features found only
763 in some particular @file{Makefile.rules}.
771 @node Linux, System-Less, Properties of Specific Makefile.rules, Properties of Specific Makefile.rules
774 This @file{Makefile.rules} is used not only for Linux as the name
775 sugest, but also for other Unices and even for Windows.
778 The name of the operating system (OS) where make was invoked.
782 Should specify the name of OS where the resulting binary should be
783 used. If not specified manually, it equals to BUILD_OS.
788 @node System-Less, RTEMS, Linux, Properties of Specific Makefile.rules
789 @subsection System-Less
791 @node RTEMS, , System-Less, Properties of Specific Makefile.rules
795 @node Running OMK under Windows OS, Interfacing OMK to popular IDEs, Properties of Specific Makefile.rules, OMK User's Manual
796 @section Running OMK under Windows OS
798 @node Interfacing OMK to popular IDEs, Troubleshooting, Running OMK under Windows OS, OMK User's Manual
799 @section Interfacing OMK to popular IDEs
803 KDevelop has support for custom build systems. To use KDevelop to
804 develop projects using OMK follow these steps. These steps are valid for
805 version 3.5.0 of KDevelop, but for previous versions it doesn't differ
810 Import project to KDevelop (from menu choose @emph{Project---Import
811 existing project}). Select the type of project to @emph{Generic C
812 Application (Custom Buildsystem)}.
818 Then answer to following dialogs as you want.
823 @image{kdevelop3} @image{kdevelop4}
827 If you are working only on some small part of the bigger project, you
828 usually don't want to recompile the whole project every time. In
829 @emph{Project---Project Options}, you can specify the subdirectory where to
836 If you want to switch between several configurations easily (see also
837 @ref{Configuration and Conditional Compilation}), in the same dialog
838 you can add @option{-e} to make options. This makes environment variables
839 have higher precedence than those in @file{config.omk-default}. Then,
840 you can define several environments with different
841 @code{CONFIG_@var{xxx}} variables and their values.
847 You can easily switch the configurations from @emph{Build---Make
857 @subsection Emacs, VIM, etc.
859 Since OMK compilation is started by executing @command{make} command,
860 many common editors can work easily with OMK.
862 Under Emacs, you can use @command{compile} or @command{recompile}
863 commands as you are used to do.
865 @node Troubleshooting, , Interfacing OMK to popular IDEs, OMK User's Manual
866 @section Troubleshooting
870 If you rename some file or directory and then you can't compile your
871 project, call @command{make clean} in the directory with errors. The
872 reason for this behavior is that OMK remembers dependencies of every
873 file. After renaming something, the original name is still stored in
874 dependencies, but make doesn't know how to create this non-existent
878 Sometimes, you may want to compile one file the same way as OMK does
879 it, but run the compilation manually from command line. For example,
880 you want to debug some preprocessor macros and you only want to
881 produce preprocessed source instead of object file.
883 To compile something manually, you can run OMK with @command{make
884 V=2}. This will print all commands executed together with directory
885 navigation messages. Find the command you want to execute manually in
886 the output. To run it, you need to change the working directory to the
887 correct one in the @file{_build} tree. The correct directory can be
888 found in make output on the line @samp{Entering directory} preceding
892 @node Original README, OMK Development, OMK User's Manual, Top
893 @chapter Original README
895 Since this manual still doesn't cover all aspects of OMK, we include
896 here a @file{README.rules} file, which was written for the first version
899 @b{Important notice:} This make system uses features found in recent
900 versions of GNU Make program. If you encounter problems with package
901 building, check, that you use correct version of Make program. The
902 Make older than version 3.80, could not be used. Even Make version
903 3.80 has annoying bug which causes building fail with misleading
904 message "virtual memory exhausted". Please, upgrade at least to
905 version 3.81 of GNU Make.
907 There is list of features which we want to solve with our make system:
910 Central @file{Makefile.rules} for most of components of a bigger project.
912 FIXME (our CAN framework includes more libraries common with our other
913 projects, we need to separate some utility libraries etc.)
915 The rules in more spread Makefiles are way to the hell (update for
916 different kernel, RT-Linux etc would be nightmare in other case).
918 Make system should allow to freely move cross-dependant components in
919 directory structure without need to update users of moved component (I
920 hate somethink like @option{-I../../sched/rtlshwq/include} in CAN makefiles for
921 example. If a component is renamed or version is added to then name,
922 all Makefiles in CAN will require update).
924 Make system should be able to compile mutually cross-dependant
925 libraries and should ensure, that change in one component sources or
926 headers would result in relink or rebuild in components linked against
927 that library or including modified header file.
929 Make system has to enable compilation out of OCERA full source tree
930 (we would lost many users of particular components in other case).
932 Compile should be able to do all above work without need to install
933 any files before successful finish of build.
935 Because we use some libraries for RT-Linux build and user-space build,
936 we need to solve how to compile from same sources to both targets.
938 The build system should allow to call make for particular source
939 subdirectory. Time of recursive make through all subdirectories is
942 Make system should enable to build out of sources tree (else clean or
943 working with CVS sandbox gets fussy and simultaneous multiple targets
946 It would be good, if there is a possibility to call make from
947 read-only media sources.
949 Make system should store results of build in some separate directory
950 structure to simple install and testing.
952 Makefiles in sources directories should be simple.
955 There is probably only one alternative fully supporting above requirements
956 and it is GNU Autoheader...Automake...Autoconf... system.
957 But it is complicated and requires big amount of support files.
958 It would be acceptable if it could be easily used for OCERA framework.
959 But there are important show stoppers for that system:
962 It would require deep revision of all OCERA CVS contents and agreement
963 on this would be problematic
965 This system is not well prepared for dual compilation for Linux and
966 RT-Linux sub-targets. It would mean many changes in default autoconf
967 setup to support this. Probably simplest way would be to rebuild GCC
968 tool chain for something like i586-elf-rtlinux. This would require
969 even more space for OCERA development.
972 The problem calls for some solution, which would have minimal impact
973 on other components and would be elegant and would be maintainable
974 and small, because our main goal is components development and not
975 make systems development.
977 There is result of our trial. It is OMK make system.
978 The @file{Makefile} and @file{Makefile.omk} files should be in all source
979 directories. Common @file{Makefile.rules} file is required in the toplevel
980 sources directory. Alternatively this file could be moved
981 to link tree pointing into readonly media or can be anywhere
982 else if @code{MAKERULES_DIR} and @code{SOURCES_DIR} are specified.
984 @c !!! tohle tam nejak zmizelo, mozna by to chtelo skontrolovat, ze to
985 @c sedi s aktualnim stavem
988 Syntax of Makefile.omk files is for usual cases compatible
989 to Automake's Makefile.am descriptions. There are specific targets
990 for RT-Linux and Linux kernel related stuff
992 Makefile.omk user defined variables
995 list of subdirectories intended for make from actual directory
997 list of the user-space libraries
998 @item shared_LIBRARIES
999 list of the user-space shared libraries
1000 @item kernel_LIBRARIES
1001 list of the kernel-space libraries
1002 @item rtlinux_LIBRARIES
1003 list of the RT-Linux kernel-space libraries
1004 @item include_HEADERS
1005 list of the user-space header files
1006 @item nobase_include_HEADERS
1007 headers copied even with directory part
1008 @item kernel_HEADERS
1009 list of the kernel-space header files
1010 @item rtlinux_HEADERS
1011 list of the RT-Linux kernel-space header files
1013 list of the require binary programs
1014 @item utils_PROGRAMS
1015 list of the development utility programs
1016 @item kernel_MODULES
1017 list of the kernel side modules/applications
1018 @item rtlinux_MODULES
1019 list of RT-Linux the kernel side modules/applications
1021 list of specific target sources
1023 additional include directories and defines for user-space
1024 @item kernel_INCLUDES
1025 additional include directories and defines for kernel-space
1026 @item rtlinux_INCLUDES
1027 additional include directories and defines for RT-Linux
1028 @item default_CONFIG
1029 list of default config assignments CONFIG_XXX=y/n ...
1032 The Makefile is same for all sources directories and is only 14 lines
1033 long. It is there only for convenience reasons to enable call "make"
1034 from local directory. It contains code which locates
1035 @file{Makefile.rules} in actual or any parent directory. With standard
1036 BASH environment it works such way, that if you get into sources
1037 directory over symbolic links, it is able to unwind yours steps back
1038 => you can make links to readonly media component directories, copy
1039 @file{Makefile.rules}, Makefile and toplevel Makefile.omk, adjust
1040 Makefile.omk to contain only required components and then call make in
1041 top or even directories after crossing from your tree to readonly
1044 The system compiles all files out of source directories. The actual
1045 version of system is adapted even for OCERA tree mode if
1046 @code{OCERA_DIR} variable is defined in @file{Makefile.rules}
1048 There are next predefined directory name components, which can be
1052 @item BUILD_DIR_NAME = _build
1053 prefix of directory, where temporary build files are stored
1054 @item COMPILED_DIR_NAME = _compiled
1055 prefix of directory, where final compilation results are stored
1056 @item GROUP_DIR_NAME = yyy
1057 this is used for separation of build sub-trees in OCERA environment
1058 where more @file{Makefile.rules} is spread in the tree
1061 Next directories are used:
1064 @item KERN_BUILD_DIR := $(MAKERULES_DIR)/$(BUILD_DIR_NAME)/kern
1065 directory to store intermediate files for kernel-space targets
1066 @item USER_BUILD_DIR := $(MAKERULES_DIR)/$(BUILD_DIR_NAME)/user
1067 directory to store intermediate files for user-space targets
1069 @item USER_INCLUDE_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/include
1070 directory to store exported include files which should be installed later
1071 on user-space include path
1072 @item USER_LIB_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/lib
1073 same for user-pace libraries
1074 @item USER_UTILS_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/bin-utils
1075 utilities for testing, which would not probably be installed
1076 @item USER_BIN_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/bin
1077 binaries, which should go into directory on standard system PATH
1078 (/usr/local/bin, /usr/bin or $(prefix)/bin)
1080 @item KERN_INCLUDE_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/include-kern
1081 directory to store exported include files which should be installed later
1082 on kernel-space include path
1083 @item KERN_LIB_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/lib-kern
1084 same for kernel-pace libraries
1085 @item KERN_MODULES_DIR := $(MAKERULES_DIR)/$(COMPILED_DIR_NAME)/modules
1086 builded modules for Linux kernel or RT-Linux system
1089 There is more recursive passes through directories to enable
1090 mutual dependant libraries and binaries to compile.
1091 Next passes are defined
1094 @item default-config
1095 generates @file{config.omk-default} or xxx-default (FIXME) configuration file
1097 checks and creates required build directories
1099 copies header files to @code{USER_INCLUDE_DIR} and @code{KERN_INCLUDE_DIR}
1101 builds objects in USER_BUILD_DIR/@var{relative path} and creates libraries
1103 @item binary-pass and utils-pass
1104 links respective binaries in USER_@{BIN,UTILS@}_DIR directory. If some
1105 object file is missing it compiles it in USER_BUILD_DIR/@var{relative path}
1106 @item kernel-lib-pass
1107 builds libraries for kernel space targets
1109 builds kernel modules
1112 The amount of passes is relatively high and consumes some time. But
1113 only other way to support all required features is to assemble one big
1114 toplevel Makefile, which would contain all components and targets
1117 Drawbacks of designed make system
1120 the system is not as fast as we would like
1122 it lacks Autoconf and configure extensive support for many systems
1123 from UNIX to DOS and WINDOWS
1125 it does not contain support for checking existence of target
1126 libraries and functionalities as GNU Autoconf
1128 it is heavily dependant on GNU MAKE program. But it would not be big
1129 problem, because even many commercial applications distribute GNU MAKE
1130 with them to be able to work in non-friendly systems
1132 the key drawback is dependence on recent MAKE version 3.80 and better
1133 and even version 3.80 of MAKE has important bug, which has been
1134 corrected in newer sources (FIXME)
1137 The last point is critical. I have not noticed it first, because
1138 I use Slackware-9.2 and it contains latest released version
1139 of MAKE (version 3.80).
1140 The problem appears when I have tried to build bigger libraries.
1141 There is bug in version 3.80, which results in misleading
1142 error "Virtual memory exhausted". It is known bug with ID 1517
1145 * long prerequisite inside eval(call()) => vm exhausted, Paul D. Smith
1149 I have optimized some rules to not push memory to the edge,
1150 but there could be still issues with 3.80 version.
1152 I have downloaded latest MAKE CVS sources. The compilation required
1153 separate lookup and download for .po files and full Autoheader... cycle.
1154 I have put together package similar to release. Only ./configure --prefix=...
1155 and make is required. CVS sources contains version 3.81beta1.
1156 You can download prepared sources archive from
1157 @indicateurl{http://paulandlesley.org/make/make-3.81beta1.tar.bz2}
1158 Or you can get our local copy from
1159 @indicateurl{http://cmp.felk.cvut.cz/~pisa/can/make-3.81beta1.tar.gz}
1161 The archive contains even "make" binary build by me, which should work
1162 on other Linux distributions as well. Older version of MAKE (3.79.x
1163 released about year 2000) found on Mandrake and RedHat are not
1164 sufficient and do not support eval feature. I do not expect, that
1165 Debian would be more up-to-date or contain fixes to MAKE vm exhausted
1168 The local CTU archive with our CAN components prepared for inclusion
1169 into OCERA SF CVS could be found in my "can" directory
1171 @indicateurl{http://cmp.felk.cvut.cz/~pisa/can/ocera-can-031212.tar.gz}
1173 The code should build for user-space with new make on most of Linux distros
1174 when make is updated.
1176 If you want to test compile for RT-Linux targets, line
1179 #RTL_DIR := /home/cvs/ocera/ocera-build/kernel/rtlinux
1182 in @file{Makefile.rules} has to be activated and updated
1183 to point RT-Linux directory containing "rtl.mk".
1184 There is only one library ("ulutrtl") and test utility compiled for RT-Linux
1185 (@file{can/utils/ulut/ul_rtlchk.c}).
1187 The next line, if enabled, controls compilation in OCERA project tree
1190 #OCERA_DIR := $(shell ( cd -L $(MAKERULES_DIR)/../../.. ; pwd -L ) )
1193 The LinCAN driver has been updated to compile out of source directories.
1195 Please, check, if you could compile CAN package and help us with integration
1196 into OCERA SF CVS. Send your comments and objections.
1198 The OMK system has been adapted to support actual OCERA configuration process.
1199 I am not happy with ocera.mk mix of defines and poor two or three rules,
1200 but OMK is able to overcome that.
1202 The OMK system has integrated rules (default-config) to build default
1203 configuration file. The file is named @file{config.omk-default} for
1204 the stand-alone compilation. The name corresponds to OCERA config +
1205 "-default" if OCERA_DIR is defined. This file contains statements
1206 from all @code{default_CONFIG} lines in all @file{Makefile.omk}. The
1207 file should be used for building of own @file{config.omk} file, or as
1208 list for all options if Kconfig is used.
1210 @c @chapter OMK Reference
1212 @node OMK Development, Variable Index, Original README, Top
1213 @chapter OMK Development
1217 @node Variable Index, , OMK Development, Top
1218 @unnumbered Variable Index
1222 @c @node Concept Index, , Variable Index, Top
1223 @c @unnumbered Concept Index