CONCERTO README
===================

What is it?
-------------------
Concerto is a simple single-pass, non-recursive, full dependency-managed Makefile system.

How it works
-------------------
Concerto looks for sub-makefiles called concerto.mak in the directories (and their corresponding subdirectories) specified by the `DIRECTORIES` variable. It will "include" each module's concerto.mak file into the overall build and resolve all build related macros associated with that module. In this way, it is "single pass" in that all concerto.mak makefiles are read once. The Concerto Build System makefiles like the `prelude.mak` and `finale.mak` (and submakefiles therein) are read once per module. These are used to define the make-target macros needed to establish the *full* depedency tree of the entire build system. 

Build System Files:
-------------------

* `definitions.mak` - useful macros for finding source files
* `rules.mak` - internal top level file. Include this in your Makefile. 
* `os.mak` - determines host os
* `machine.mak` - determines host cpu
* `target.mak` - determines target variables and build system include paths, variables. This can be replaced (see above).
* `scm.mak` - tries to extract SCM version information (SVN/GIT)
* `prelude.mak` and `finale.mak` - generates non-recursive build system macros and variables per module.
* `compilers/*` - Compiler specific files
* `os/*` - OS specific installing/removing rules
* `tools/*` - tools specific rules.
* `components/*` - contains rules to build with components that do not work well with standard package management tools like pkg-config
* `shell.mak` - Contains shell macros per OS.
* `combo.mak` and `combo_filters.mak` - contains rules to simulatenously build on multiple compilers. 
* `packages.mak` - contains package management rules per OS.

How to use it
-------------------
* Download or copy the concerto folder to somewhere on your build system from `git clone https://github.com/emrainey/Concerto`
* Create a Makefile at the top of you project consisting of the following:

Top Level Makefile per project

    # Path to concerto install or use environment variable
    CONCERTO_ROOT ?= ../concerto
    # [OPTIONAL] if DIRECTORIES is not specified concerto assumes "source"
    DIRECTORIES  := src docs
    # [OPTIONAL] BUILD_TARGET is used to reflect specific needs of your build system.
    # if not specified concerto's default target.mak is used instead
    BUILD_TARGET := $(abspath .)/target.mak
    # [REQUIRED] This calls concerto
    include $(CONCERTO_ROOT)/rules.mak

How to auto-download if Concerto is not present
    
    # Path to concerto install or use environment variable
    CONCERTO_ROOT ?= ../concerto
    # [OPTIONAL] check to see if the path really exists to CONCERTO_ROOT, if it does not, execute a shell command to pull it down with git
    $(if $(realpath $(CONCERTO_ROOT)),,$(call $($(shell git clone http://github.com/emrainey/Concerto $(CONCERTO_ROOT)))))
    ...
    # This calls concerto
    include $(CONCERTO_ROOT)/rules.mak


What's in the concerto.mak
-------------------
`concerto.mak` files can contain the following (although it is normally shorter):

    _MODULE=<optional module name>
    include $(PRELUDE)
    TARGET=<name of the object created>
    TARGETTYPE=<exe|library|dsmo|prebuilt|jar>
    CSOURCES=<list of C files>
    CPPSOURCES=<list of C++ files>
    ASSEMBLY=<list of .S Files>
    KCSOURCES=<list of KernelC .k files>
    IDIRS+=<include directories>
    DEFS+=<defines>
    STATIC_LIBS=<static libraries within the build system>
    SHARED_LIBS=<shared libraries within the build system>
    SYS_STATIC_LIBS=<static libraries outside the build system>
    SYS_SHARED_LIBS=<shared libraries outside the build system>
    LINKER_FILES=<list of linker files within the build system>
    PREBUILT=<It specifies a single resource to be copied into the target output, only used with the prebuilt TARGETTYPE>
    include $(FINALE)

A typical `concerto.mak` is shorter:

    include $(PRELUDE)
    TARGET=mytest
    TARGETTYPE=exe
    SYS_STATIC_LIBS+=some_system_lib
    CSOURCES=main.c
    include $(FINALE)

Internal Variables
-------------------
The following variables and macros are available for use in a `concerto.mak` file.

* `_MODULE` - the name of the module (if not defined, the containing folder name will be used).
* `TARGET` - the name of the component to build. Prefixes and postfixes will be added by the build system, do not add them yourself.
* `TARGETTYPE` - possible values are:
 + exe - binary executable
 + library - static library
 + dsmo - dynamic shared library
 + prebuilt - a prebuilt binary
 + jar - a Java jar file
 + doxygen - A doxygen build
 + deb - A debian package (control file is required)
* `SYS_SHARED_LIBS` - dynamic libraries for which no dependencies are generated (which implies that they are outside the build system).
* `SYS_STATIC_LIBS` - static libraries for which no dependencies are generated (which implies that they are outside the build system). 
* `SHARED_LIBS` - dynamic libraries for which dependencies are generated (which implies that they are inside the build system).
* `STATIC_LIBS` - static libraries for which dependencies are generated (which implies that they are inside the build system).
* `ASSEMBLY` - S files which must be in the same folder.
* `CSOURCES` - C files which must be in the same folder.
* `CPPSOURCES` - C++ files which must be in the same folder.
* `JSOURCES` - Java files for Jar targets
* `IDIRS` - include directories
* `LDIRS` - library link paths
* `DEFS` - #defines to pass to the compiler

Useful Macros
------------------
    
    # list of files with extension .ext in "dir" and any sub-directory of "dir"
    $(call all-type-files-in,<ext>,<dir>)
    # list of files with extension .ext that exist inside this module (including any sub-directories)
    $(call all-type-files,<ext>)
    # list of c files c that exist inside this module (including any sub-directories)
    $(call all-c-files)
    # list of c files c that exist in dir (including any sub-directories). dir is relative to the module directory
    $(call all-c-files-in,<dir>)
    
See `definitions.mak` and `shell.mak` for other supported file extensions.

External Variables
------------------
The preceding variables can be set in the command shell and `make` will import them.

* `NO_OPTIMIZE=1` - disables optimization in the compiler. The target build will be built follow normal debugging flags on this platform.
* `CHECK_MISRA=1` - it enables misra compliance checking however it is compiler dependant
* `KEEP_ASM=1` - it keeps generated assembly listings however it is compiler dependant
* `KEEP_VCC=1` - keep generated VCOP-C code however this is for ARP32/VCOP compiler only
* `BUILD_DEBUG=1` - turns on explicit build output from each command
* `TARGET_PLATFORM` - indicates the platform to build for (assumes 'PC' if not set).
* `TARGET_OS` = LINUX __or__ Windows_NT __or__ DARWIN __or__ QNX
* `TARGET_CPU` = ARM __or__ X86 __or__ X86_64 __or__ c64t  __or__ c67x
* `TARGET_BUILD` = debug __or__ release __or__ production - used to generate debuggable components, optimized components or finale builds.
* `HOST_OS` = LINUX __or__ Windows_NT 
* `HOST_CPU` = X86  __or__ X86_64
* `HOST_PLATFORM` = PC (ususally)

Supported Platforms and Targets:
--------------------------------

Host Environments:
* LINUX
* DARWIN
* WINDOWS (NT or later)
* CYGWIN

Target Environments:
* LINUX
* DARWIN
* WINDOWS (NT or later)
* CYGWIN
* QNX 

Target CPUs:
* ARM
* X86
* X86_64
* TI DSPs


Windows Builds
--------------

When building on Windows, you need to install MinGW to get the GNU Make for Windows. Add the path to MinGW's bin/ folder to your `PATH` variable. You may want to rename or copy it from _mingw32-make.exe_ to _make.exe_.

Available Build System Targets
------------------------------

Concerto provides the following useful rules:

`make scrub` This will delete the build output directory
`make targets` Lists all targets defined by concerto.mak files
`make <target>` This will build the specified target and any of its dependencies
`make <target>_clean` Cleans out the specified target
`make clean` Cleans out all build artifacts for all targets
`make vars` Outputs the module variables as concerto thinks they are. Useful for debugging.

Build System Layout
-------------------
The typical folder layout (the default configuration) is:

_project_folder_/

+ _Makefile_
+ include/
+ source/_any depth of folders_/_concerto.mak_
+ out/$(TARGET_PLATFORM)/$(TARGET_CPU)/$(TARGET_OS)/$(TARGET_BUILD)/_components_

Multiproject Builds:
--------------------
For multiproject builds the layout is just all _project_folder_ folders as peers within a parent folder which will have the `out` folder as a child. The `Makefile` for a multiproject build simply notes the subdirs of the build.

    DIRECTORIES := someproject/source someproject/docs
    DIRECTORIES += otherproject/source otherproject/docs

Concerto has to be careful to make sure no `_MODULES` are named the same in these two projects, so it alters the `_MODULE` name to guarentee uniqueness (otherwise you would have two components share the same output folder for intermediate objects and you may be compiler/linker collisions and very odd behavior).