From: Leandro Lucarella <llucarella@integratech.com.ar>
Date: Thu, 17 Sep 2009 13:30:56 +0000 (-0300)
Subject: Initial import of the all mighty make based build system
X-Git-Url: https://git.llucax.com/software/makeit.git/commitdiff_plain/a4419536621943012477a48fc1fc5b1c730a2834?ds=sidebyside

Initial import of the all mighty make based build system

This is a test/example of a nice make based build system that support
automatic dependencies, variants, separated build directory, automatic
generation of pre-compiled header, subproject embedding and some other
goodies.

The only important file is Lib.mak, all the rest is just an usage example
and/or test.
---

a4419536621943012477a48fc1fc5b1c730a2834
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..567609b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+build/
diff --git a/Build.mak b/Build.mak
new file mode 100644
index 0000000..0f18c0b
--- /dev/null
+++ b/Build.mak
@@ -0,0 +1,15 @@
+
+# Include sub-directories makefiles
+
+C := subproj
+include $T/subproj/Build.mak
+
+C := lib1
+include $T/lib1/Build.mak
+
+C := lib2
+include $T/lib2/Build.mak
+
+C := prog
+include $T/prog/Build.mak
+
diff --git a/Config.mak b/Config.mak
new file mode 100644
index 0000000..e76a8a9
--- /dev/null
+++ b/Config.mak
@@ -0,0 +1,10 @@
+
+# Use debug flavor by default
+F := dbg
+
+# C compiler
+CC := gcc
+
+# Use precompiled headers
+GCH := 1
+
diff --git a/Lib.mak b/Lib.mak
new file mode 100644
index 0000000..259a659
--- /dev/null
+++ b/Lib.mak
@@ -0,0 +1,243 @@
+
+ifndef Lib.mak.included
+Lib.mak.included := 1
+
+# These variables should be provided by the includer Makefile:
+# P should be the project name, mostly used to handle include directories
+# T should be the path to the top-level directory.
+# C should be the path to the current directory.
+
+# Load top-level directory local configuration
+sinclude $T/Config.mak
+
+# Verbosity flag (empty show nice messages, 1 be verbose)
+# honour make -s flag
+override V := $(if $(findstring s,$(MAKEFLAGS)),1,$V)
+
+# Flavor (variant), should be one of "dbg", "opt" or "cov"
+F ?= opt
+
+# Use C++ linker by default
+LINKER := $(CXX)
+
+# Use precompiled headers if non-empty
+GCH ?=
+
+
+# Directories
+##############
+
+# Use absolute paths to avoid problems with automatic dependencies when
+# building from subdirectories
+T := $(abspath $T)
+
+# Name of the current directory, relative to $T
+R := $(subst $T,,$(patsubst $T/%,%,$(CURDIR)))
+
+# Base directory where to put variants
+D ?= $T/build
+
+# Generated files top directory
+G ?= $D/$F
+
+# Objects (and other garbage like precompiled headers and dependency files)
+# directory
+O ?= $G/obj
+
+# Binaries directory
+B ?= $G/bin
+
+# Libraries directory
+L ?= $G/lib
+
+# Includes directory
+I ?= $G/include
+
+# Generated includes directory
+J ?= $G/geninc
+
+
+# Functions
+############
+
+# Find sources files and get the corresponding object names
+# The first argument should be the sources extension ("c" or "cpp" typically)
+# It expects the variable $T and $O to be defined as commented previously in
+# this file. $C should be defined to the path to the current directory relative
+# to the top-level.
+find_objects = $(patsubst $T/%.$1,$O/%.o,$(shell find $T/$C -name '*.$1'))
+
+# Abbreviate a file name. Cut the leading part of a file if it match to the $T
+# directory, so it can be displayed as if it were a relative directory. Take
+# just one argument, the file name.
+abbr = $(addprefix $(shell echo $R | sed 's|/\?\([^/]\+\)/\?|../|g'),\
+		$(subst $T,.,$(patsubst $T/%,%,$1)))
+
+# Execute a command printing a nice message if $V is empty
+# The first argument is mandatory and it's the command to execute. The second
+# and third arguments are optional and are the target name and command name to
+# pretty print.
+vexec = $(if $V,,\
+		echo '   $(notdir $(if $3,$(strip $3),$(firstword $1))) \
+				$(call abbr,$(if $2,$(strip $2),$@))' ; )$1
+
+# Same as vexec but it silence the echo command (prepending a @).
+exec = $(if $V,,@)$(call vexec,$1,$2,$3)
+
+# Compile a source file to an object, generating pre-compiled headers and
+# dependencies. The pre-compiled headers are generated only if the system
+# includes change. This function is designed to be used as a command in a rule.
+# It takes one argument only, the type of file to compile (typically "c" or
+# "cpp"). What to compile and the output files are built using the automatic
+# variables from a rule.
+define compile
+$(if $(GCH),\
+@if test -f $O/$*.d; then \
+	tmp=`mktemp`; \
+	h=`awk -F: '!$$0 {f = 1} $$0 && f {print $$1}' $O/$*.d`; \
+	grep -h '^#include <' $(call abbr,$<) $$h | sort -u > "$$tmp"; \
+	if diff -q -w "$(call abbr,$O/$*.$1.h)" "$$tmp" > /dev/null 2>&1; \
+	then \
+		rm "$$tmp"; \
+	else \
+		mv "$$tmp" "$(call abbr,$O/$*.$1.h)"; \
+		$(call vexec,$(COMPILE.$1) -o "$O/$*.$1.h.gch" "$O/$*.$1.h",\
+				$O/$*.$1.h.gch); \
+	fi \
+else \
+	touch "$(call abbr,$O/$*.$1.h)"; \
+fi \
+)
+$(call exec,$(COMPILE.$1) -o $@ -MMD -MP $(if $(GCH),-include $O/$*.$1.h) $<)
+endef
+
+# Link object files to build an executable. The objects files are taken from
+# the prerequisite files ($O/%.o). If in the prerequisite files are shared
+# objects ($L/lib%.so), they are included as libraries to link to (-l%). This
+# function is designed to be used as a command in a rule. The ouput name is
+# taken from the rule automatic variables. If an argument is provided, it's
+# included in the link command line. The variable LINKER is used to link the
+# executable; for example, if you want to link a C++ executable, you should use
+# LINKER := $(CXX).
+link = $(call exec,$(LINKER) $(LDFLAGS) $(TARGET_ARCH) -o $@ $1 \
+		$(patsubst $L/lib%.so,-l%,$(filter %.so,$^)) \
+		$(foreach obj,$(filter %.o,$^),$(obj)))
+
+
+# Overrided flags
+##################
+
+# Warn about everything
+override CPPFLAGS += -Wall
+
+# Use the includes directories to search for includes
+override CPPFLAGS += -I$I -I$J
+
+# Be standard compilant
+override CFLAGS += -std=c99 -pedantic
+override CXXFLAGS += -std=c++98 -pedantic
+
+# Use the generated library directory to for libraries
+override LDFLAGS += -L$L -Wall
+
+# Make sure the generated libraries can be found
+export LD_LIBRARY_PATH := $L:$(LD_LIBRARY_PATH)
+
+
+# Variant flags
+################
+
+ifeq ($F,dbg)
+override CPPFLAGS += -ggdb -DDEBUG
+endif
+
+ifeq ($F,opt)
+override CPPFLAGS += -O2 -DNDEBUG
+endif
+
+ifeq ($F,cov)
+override CPPFLAGS += -ggdb -pg --coverage
+override LDFLAGS += -pg --coverage
+endif
+
+
+# Automatic rebuilding when flags or commands changes
+######################################################
+
+# Re-compile C files if one of this variables changes
+COMPILE.c.FLAGS := $(CC) ~ $(CPPFLAGS) ~ $(CFLAGS) ~ $(TARGET_ARCH)
+
+# Re-compile C++ files if one of this variables changes
+COMPILE.cpp.FLAGS := $(CXX) ~ $(CPPFLAGS) ~ $(CXXFLAGS) ~ $(TARGET_ARCH)
+
+# Re-link binaries and libraries if one of this variables changes
+LINK.o.FLAGS := $(LD) ~ $(LDFLAGS) ~ $(TARGET_ARCH)
+
+
+# Default rules
+################
+
+$O/%.o: $T/%.c $G/compile-c-flags
+	$(call compile,c)
+
+$O/%.o: $T/%.cpp $G/compile-cpp-flags
+	$(call compile,cpp)
+
+$B/%: $G/link-o-flags
+	$(call link)
+
+$L/%.so: override CFLAGS += -fPIC
+$L/%.so: override CXXFLAGS += -fPIC
+$L/%.so: $G/link-o-flags
+	$(call link,-shared)
+
+.PHONY: clean
+clean:
+	$(call exec,$(RM) -r $D,$D)
+
+
+# Automatic dependency handling
+################################
+
+sinclude $(shell test -d $O && find $O -name '*.d')
+
+
+# Create build directory structure
+###################################
+
+# Create a file with flags used to trigger rebuilding when they change. The
+# first argument is the name of the file where to store the flags, the second
+# are the flags and the third argument is a text to be displayed if the flags
+# have changed.  This should be used as a rule action or something where
+# a shell script is expected.
+gen_rebuild_flags = if test x"$2" != x"`cat $1 2>/dev/null`"; then \
+		test -f $1 && echo "$3"; \
+		echo "$2" > $1 ; fi
+
+# Create $O, $B, $L, $I and $J directories and replicate the directory
+# structure of the project into $O. Create one symlink "last" to the current
+# build directory and another to use as include directory.  It update the flags
+# files to detect flag and/or compiler changes to force a rebuild.
+#
+# NOTE: the second mkdir can yield no arguments if the project don't have any
+#       subdirectories, that's why the current directory "." is included, so it
+#       won't show an error message in case of no subdirectories.
+setup_build_dir__ := $(shell \
+	mkdir -p $O $B $L $I $J; \
+	mkdir -p . $(addprefix $O,$(patsubst $T%,%,\
+			$(shell find $T -type d -not -path '$D*'))); \
+	$(call gen_rebuild_flags,$G/compile-c-flags, \
+			$(COMPILE.c.FLAGS),C compiler or flags;); \
+	$(call gen_rebuild_flags,$G/compile-cpp-flags, \
+			$(COMPILE.cpp.FLAGS),C++ compiler or flags;); \
+	$(call gen_rebuild_flags,$G/link-o-flags, \
+			$(LINK.o.FLAGS),linker or link flags;); \
+	test -L $I/$P || ln -s $T $I/$P; \
+	test -L $D/last || ln -s $F $D/last )
+
+# Print any generated message (if verbose)
+$(if $V,,$(if $(setup_build_dir__), \
+	$(info !! Something changed: $(setup_build_dir__) \
+			re-building affected files...)))
+
+endif
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..f78a4f0
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,10 @@
+
+# Top-level directory
+T := .
+
+# Default goal for building this directory
+.DEFAULT_GOAL := all
+
+# Include the top-level makefile
+include $T/Toplevel.mak
+
diff --git a/README b/README
new file mode 100644
index 0000000..083dea7
--- /dev/null
+++ b/README
@@ -0,0 +1,27 @@
+
+This is a test/example for a nice Make based build system.
+
+The Config.mak should not be saved to the repositories usually, but in this
+case it is because part of this demonstration is to show how to customize the
+build system through Config.mak, and specially to show how a project can be
+"embedded" into another tweaking the Config.mak.
+
+lib1 is a standalone C library compiled into a shared object.  lib2 is another
+shared library which uses lib1 and subproj, which is a standalone project
+"embedded" into this one. subproj produces another standalone shared object.
+Finally, prog is a program which uses lib1 and lib2.
+
+Every project have it's copy of Lib.mak and it's own Toplevel.mak, which has
+some global permanent configuration (which doesn't depends on users taste, it
+just have information about the project, like it's name, and does the work to
+include Lib.mak, etc.). Lib.mak shouldn't be modified ever (unless you're
+hacking the build system) and Toplevel.mak should be changes very rarely.
+
+Then each directory containing some library or program to build (or directories
+to include) has a Build.mak, which has only the logic to build the
+programs/libraries. A well-known Makefile is added to each directory where you
+want to be able to do "make", just for convenience. This Makefile should be
+created once, with the default target to build and path to the top-level
+directory and never touched again. Build.mak should be changes only to add new
+programs or libraries to build.
+
diff --git a/Toplevel.mak b/Toplevel.mak
new file mode 100644
index 0000000..bcf2b56
--- /dev/null
+++ b/Toplevel.mak
@@ -0,0 +1,15 @@
+
+# Project name
+P := remake
+
+# Include the build system library
+include $T/Lib.mak
+
+# Include the Build.mak for this directory
+include $T/Build.mak
+
+# Phony rule to make all the targets (sub-makefiles can append targets to build
+# to the $(all) variable).
+.PHONY: all
+all: $(all)
+
diff --git a/lib1/Build.mak b/lib1/Build.mak
new file mode 100644
index 0000000..7661dc4
--- /dev/null
+++ b/lib1/Build.mak
@@ -0,0 +1,7 @@
+
+$L/liblib1.so: LINKER := $(CC)
+$L/liblib1.so: $(call find_objects,c)
+
+.PHONY: lib1
+lib1: $L/liblib1.so
+
diff --git a/lib1/Makefile b/lib1/Makefile
new file mode 100644
index 0000000..fe10532
--- /dev/null
+++ b/lib1/Makefile
@@ -0,0 +1,10 @@
+
+# Top-level directory
+T := ..
+
+# Include the top-level build
+include $T/Toplevel.mak
+
+# Default goal for building this directory
+.DEFAULT_GOAL := $L/liblib1.so
+
diff --git a/lib1/lib1.c b/lib1/lib1.c
new file mode 100644
index 0000000..e7212f4
--- /dev/null
+++ b/lib1/lib1.c
@@ -0,0 +1,9 @@
+
+#include "lib1.h"
+#include <stdio.h>
+
+void lib1(void)
+{
+	printf("lib1()\n");
+}
+
diff --git a/lib1/lib1.h b/lib1/lib1.h
new file mode 100644
index 0000000..2aafe60
--- /dev/null
+++ b/lib1/lib1.h
@@ -0,0 +1,11 @@
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void lib1(void);
+
+#ifdef __cplusplus
+}
+#endif
+
diff --git a/lib2/Build.mak b/lib2/Build.mak
new file mode 100644
index 0000000..02841c5
--- /dev/null
+++ b/lib2/Build.mak
@@ -0,0 +1,6 @@
+
+$L/liblib2.so: $(call find_objects,cpp) $L/liblib1.so $L/libsubproj.so
+
+.PHONY: lib2
+lib2: $L/liblib2.so
+
diff --git a/lib2/Makefile b/lib2/Makefile
new file mode 100644
index 0000000..99f8aad
--- /dev/null
+++ b/lib2/Makefile
@@ -0,0 +1,10 @@
+
+# Top-level directory
+T := ..
+
+# Include the top-level build
+include $T/Toplevel.mak
+
+# Default goal for building this directory
+.DEFAULT_GOAL := $L/liblib2.so
+
diff --git a/lib2/lib2.cpp b/lib2/lib2.cpp
new file mode 100644
index 0000000..d5c07c4
--- /dev/null
+++ b/lib2/lib2.cpp
@@ -0,0 +1,15 @@
+
+#include "lib2.h"
+
+#include <remake/subproj/subproj.h>
+#include <remake/lib1/lib1.h>
+
+#include <stdio.h>
+
+void lib2(void)
+{
+	printf("lib2()\n");
+	lib1();
+	subproj();
+}
+
diff --git a/lib2/lib2.h b/lib2/lib2.h
new file mode 100644
index 0000000..80dab51
--- /dev/null
+++ b/lib2/lib2.h
@@ -0,0 +1,3 @@
+
+void lib2(void);
+
diff --git a/prog/Build.mak b/prog/Build.mak
new file mode 100644
index 0000000..d3a59ed
--- /dev/null
+++ b/prog/Build.mak
@@ -0,0 +1,8 @@
+
+$B/prog: $(call find_objects,cpp) $L/liblib1.so $L/liblib2.so
+
+.PHONY: prog
+prog: $B/prog
+
+all += prog
+
diff --git a/prog/Makefile b/prog/Makefile
new file mode 100644
index 0000000..717a34e
--- /dev/null
+++ b/prog/Makefile
@@ -0,0 +1,10 @@
+
+# Top-level directory
+T := ..
+
+# Default goal for building this directory
+.DEFAULT_GOAL := prog
+
+# Include the top-level build
+include $T/Toplevel.mak
+
diff --git a/prog/main.cpp b/prog/main.cpp
new file mode 100644
index 0000000..19ec21f
--- /dev/null
+++ b/prog/main.cpp
@@ -0,0 +1,15 @@
+
+#include <remake/lib1/lib1.h>
+#include <remake/lib2/lib2.h>
+
+#include <iostream>
+
+int main()
+{
+	std::cout << "prog:main() start\n";
+	lib1();
+	lib2();
+	std::cout << "prog:main() end\n";
+	return 0;
+}
+
diff --git a/subproj/Build.mak b/subproj/Build.mak
new file mode 100644
index 0000000..01d8779
--- /dev/null
+++ b/subproj/Build.mak
@@ -0,0 +1,9 @@
+
+$L/libsubproj.so: LINKER := $(CC)
+$L/libsubproj.so: $(call find_objects,c)
+
+.PHONY: subproj
+subproj: $L/libsubproj.so
+
+all += subproj
+
diff --git a/subproj/Config.mak b/subproj/Config.mak
new file mode 100644
index 0000000..d7624aa
--- /dev/null
+++ b/subproj/Config.mak
@@ -0,0 +1,10 @@
+
+# Use the container project top-level directory as ours
+T := ..
+
+# Include the "parent" project config
+sinclude $T/Toplevel.mak
+
+# Include the "parent" project config
+.DEFAULT_GOAL := subproj
+
diff --git a/subproj/Lib.mak b/subproj/Lib.mak
new file mode 120000
index 0000000..f07a38e
--- /dev/null
+++ b/subproj/Lib.mak
@@ -0,0 +1 @@
+../Lib.mak
\ No newline at end of file
diff --git a/subproj/Makefile b/subproj/Makefile
new file mode 100644
index 0000000..f78a4f0
--- /dev/null
+++ b/subproj/Makefile
@@ -0,0 +1,10 @@
+
+# Top-level directory
+T := .
+
+# Default goal for building this directory
+.DEFAULT_GOAL := all
+
+# Include the top-level makefile
+include $T/Toplevel.mak
+
diff --git a/subproj/Toplevel.mak b/subproj/Toplevel.mak
new file mode 100644
index 0000000..4738f47
--- /dev/null
+++ b/subproj/Toplevel.mak
@@ -0,0 +1,18 @@
+
+# Project name
+P := subproj
+
+# Load top-level directory local configuration
+sinclude $T/Config.mak
+
+# Include the build system library
+include $T/Lib.mak
+
+# Include the Build.mak for this directory
+include $T/Build.mak
+
+# Phony rule to make all the targets (sub-makefiles can append targets to build
+# to the $(all) variable).
+.PHONY: all
+all: $(all)
+
diff --git a/subproj/subproj.c b/subproj/subproj.c
new file mode 100644
index 0000000..2188e52
--- /dev/null
+++ b/subproj/subproj.c
@@ -0,0 +1,9 @@
+
+#include "subproj.h"
+#include <stdio.h>
+
+void subproj(void)
+{
+	printf("subproj()\n");
+}
+
diff --git a/subproj/subproj.h b/subproj/subproj.h
new file mode 100644
index 0000000..d29126c
--- /dev/null
+++ b/subproj/subproj.h
@@ -0,0 +1,11 @@
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void subproj(void);
+
+#ifdef __cplusplus
+}
+#endif
+