# Phil's multiplatform makefile template
# With auto-incrementing build number and automatic version.h generation
# Version 1.4, 2009-01-27
#
# The latest version of this Makefile can be found at http://www.philpem.me.uk/
#
#
# Copyright (c) 2009 Philip Pemberton <code@philpem.me.uk>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
#
#
# Instructions for use:
#   Run 'make init' to create the required directories
#   Add your source files to the 'SOURCES' list, and change the TARGET filename
#   Set the desired build type and platform in the BUILD_TYPE and PLATFORM
#     variables respectively
#   Set your project type (C only, or C++) in the SRC_TYPE variable
#   Add any libraries you need to link against to the 'LIB' list
#   Run 'make'
#
# Object files are created in the 'obj' subdirectory, from source code in the
# 'src' directory. Dependency files are created in the 'dep' directory from
# the same source code the object files are created from.
#
# Supported targets are:
#   all                 Build everything.
#   update-revision     Increment the build number without building anything.
#   clean-versioninfo   Delete src/version.h (will be rebuilt on the next
#                       'make all').
#   init                Initialise the build system for a new project.
#                       WARNING: overwrites .buildnum and src/version.h.in!
#   cleandep            Delete all dependency files.
#   clean               Delete all dependency, intermediate and target files.
#   tidy                Delete all dependency and intermediate files, leaving
#                       the target file intact.
#
# If you want to reset the build number to zero, delete '.buildnum'. This
# should be done whenever the major or minor version changes. Excluding
# .buildnum from version control may also be a good idea, depending on how
# you want your build numbers to work.
#
# The BUILD_TYPE variable contains the current build type. There are two
# supported build types:
#   debug       Debug mode - object files are compiled with debug information
#               and the target is left unstripped.
#   release     Release mode - object files are not compiled with debug info,
#               and the target is fed through strip to remove redundant
#               data.
#
# The PLATFORM variable contains the current target platform. There are two
# supported platforms:
#   linux       GNU/Linux with GNU Compiler Collection
#   win32       Windows 32-bit with MinGW
#
# The EXTSRC variable is used to specify other files to build. It is typically
# used to specify platform or build-type specific source files, e.g.
#
# ifeq ($(BUILD_TYPE),debug-memwatch)
#   CFLAGS += -g -ggdb
#   CPPFLAGS += -DMEMWATCH
#   INCPATH += ./memwatch
#   EXTSRC += memwatch/memwatch.c
# endif
#
# (example taken from one of my projects that allowed the use of Memwatch to
#  track down memory allocation/deallocation bugs)
#

####
# Build configuration
####

# version information -- major.minor.extra
# note that VER_EXTRA can be overridden on the command line, e.g.:
# make VER_EXTRA=12345 all
VER_MAJOR	= 0
VER_MINOR	= 0
VER_EXTRA	?= 

# build platform: win32 or linux
PLATFORM	?=	linux
# build type: release or debug
BUILD_TYPE	?=	debug

# target executable
TARGET		=	test

# source files that produce object files
SRC			=	main.cpp

# source type - either "c" or "cpp" (C or C++)
SRC_TYPE	=	cpp

# additional object files that don't necessarily include source
EXT_OBJ		=
# libraries to link in -- these will be specified as "-l" parameters, the -l
# is prepended automatically
LIB			=
# library paths -- where to search for the above libraries
LIBPATH		=
# include paths -- where to search for #include files (in addition to the
# standard paths
INCPATH		=
# garbage files that should be deleted on a 'make clean' or 'make tidy'
GARBAGE		=

# extra dependencies - files that we don't necessarily know how to build, but
# that are required for building the application; e.g. object files or
# libraries in sub or parent directories
EXTDEP		=

####
# Win32 target-specific settings
####
ifeq ($(strip $(PLATFORM)),win32)
	# windows executables have a .exe suffix
	TARGET := $(addsuffix .exe,$(TARGET))
	# console mode application
	EXT_CFLAGS = -mconsole
endif


####
# Tool setup
####
MAKE	=	make
CC		=	gcc
CXX		=	g++
CFLAGS	=	-Wall -pedantic -std=gnu99 $(EXT_CFLAGS)
CXXFLAGS=	-Wall -pedantic $(EXT_CXXFLAGS)
LDFLAGS	=	$(EXT_LDFLAGS)
RM		=	rm
STRIP	=	strip

###############################################################################
# You should not need to touch anything below here, unless you're adding a new
# platform or build type (or changing the version string format)
###############################################################################

####
# A quick sanity check on the platform type
####
ifneq ($(PLATFORM),linux)
ifneq ($(PLATFORM),win32)
    $(error Platform '$(PLATFORM)' not supported. Supported platforms are: linux, win32)
endif
endif

####
# Version info generation
####
# get the current build number
VER_BUILDNUM	= $(shell cat .buildnum)

# there are two ways to get the SVN rev - use svnversion, or use svn info
# then pipe through awk. which one you use is up to you.
VER_SVNREV		= $(shell LANG=C svn info 2>/dev/null || echo 'Revision: 0' | awk '/^Revision:/ { print$$2 }' )
#VER_SVNREV		= $(shell svnversion .)

# if the version string is "exported", then the CSD was not checked out of SVN
# note that if the CSD is not an SVN checkout, then @@svnrev@@ will be set to
# zero.
ifeq ($(VER_SVNREV),exported)
    VER_SVNREV	= 0
endif

# start creating the revision string
VER_FULLSTR		= $(VER_MAJOR).$(VER_MINOR).$(VER_BUILDNUM)$(VER_EXTRA)

# if this is an SVN release, include the SVN revision in the version string
ifneq ($(VER_SVNREV),0)
    VER_FULLSTR	+= (svn $(VER_SVNREV))
endif


####
# Build-type specific configuration
####
ifeq ($(BUILD_TYPE),debug)
	CFLAGS		+= -g -ggdb
	CXXFLAGS	+= -g -ggdb
else
 ifeq ($(BUILD_TYPE),release)
	CFLAGS		+= -O2
	CXXFLAGS	+= -O2
 else
 	$(error Unsupported build type: '$(BUILD_TYPE)')
 endif
endif

####
# rules
####

# object files
OBJ		=	$(addprefix obj/, $(addsuffix .o, $(basename $(SRC))) $(EXT_OBJ)) $(addsuffix .o, $(basename $(EXTSRC)))

# dependency files
DEPFILES =	$(addprefix dep/, $(addsuffix .d, $(basename $(SRC))) $(EXT_OBJ)) $(addsuffix .d, $(basename $(EXTSRC)))

# path commands
LIBLNK	=	$(addprefix -l, $(LIB))
LIBPTH	=	$(addprefix -L, $(LIBPATH))
INCPTH	=	$(addprefix -I, $(INCPATH))

CPPFLAGS +=	$(INCPTH)

####
# Make sure there is at least one object file to be linked in
####
ifeq ($(strip $(OBJ)),)
    $(error Unable to build: no object or source files specified in Makefile)
endif

####
# targets
####
.PHONY:	default all update-revision versionheader clean-versioninfo init cleandep clean tidy

all:	update-revision
	@$(MAKE) versionheader
	$(MAKE) $(TARGET)

# increment the current build number
NEWBUILD=$(shell expr $(VER_BUILDNUM) + 1)
update-revision:
	@echo $(NEWBUILD) > .buildnum

versionheader:
	@sed -e 's/@@date@@/$(shell LC_ALL=C date)/g'			\
		 -e 's/@@time@@/$(shell LC_ALL=C date +%T)/g'		\
		 -e 's/@@whoami@@/$(shell whoami)/g'				\
		 -e 's/@@hostname@@/$(shell hostname)/g'			\
		 -e 's|@@compiler@@|$(shell $(CC) $(CFLAGS) -v 2>&1 | tail -n 1 | sed -e "s;|;/;")|g'	\
		 -e 's/@@majorver@@/$(VER_MAJOR)/g'					\
		 -e 's/@@minorver@@/$(VER_MINOR)/g'					\
		 -e 's/@@extraver@@/$(subst \",,$(VER_EXTRA))/g'	\
		 -e 's/@@buildnum@@/$(VER_BUILDNUM)/g'				\
		 -e 's/@@buildtype@@/$(BUILD_TYPE)/g'				\
		 -e 's/@@svnrev@@/$(VER_SVNREV)/g'					\
		 -e 's/@@fullverstr@@/$(VER_FULLSTR)/g'				\
		 -e 's/@@cflags@@/$(CFLAGS)/g'						\
		 < src/version.h.in > src/version.h

# version.h creation stuff based on code from the Xen makefile
clean-versioninfo:
	@if [ ! -r src/version.h -o -O src/version.h ]; then \
		rm -f src/version.h; \
	fi
	@echo 0 > .buildnum

# initialise the build system for a new project
init:
	@mkdir -p src dep obj
	@echo 0 > .buildnum
	@echo '#define VER_COMPILE_DATE	"@@date@@"'				> src/version.h.in
	@echo '#define VER_COMPILE_TIME	"@@time@@"'				>> src/version.h.in
	@echo '#define VER_COMPILE_BY		"@@whoami@@"'		>> src/version.h.in
	@echo '#define VER_COMPILE_HOST	"@@hostname@@"'			>> src/version.h.in
	@echo '#define VER_COMPILER		"@@compiler@@"'			>> src/version.h.in
	@echo '#define VER_BUILD_TYPE		"@@buildtype@@"'	>> src/version.h.in
	@echo '#define VER_CFLAGS			"@@cflags@@"'		>> src/version.h.in
	@echo ''												>> src/version.h.in
	@echo '#define VER_MAJOR			@@majorver@@'		>> src/version.h.in
	@echo '#define VER_MINOR			@@minorver@@'		>> src/version.h.in
	@echo '#define VER_BUILDNUM		@@buildnum@@'			>> src/version.h.in
	@echo '#define VER_EXTRA			"@@extraver@@"'		>> src/version.h.in
	@echo '#define VER_SVNREV			@@svnrev@@'			>> src/version.h.in
	@echo ''												>> src/version.h.in
	@echo '#define VER_FULLSTR			"@@fullverstr@@"'	>> src/version.h.in
	@echo ''												>> src/version.h.in
	@echo Build system initialised

# remove the dependency files
cleandep:
	-rm $(DEPFILES)

# remove the dependency files and any target or intermediate build files
clean:	cleandep clean-versioninfo
	-rm $(OBJ) $(TARGET) $(GARBAGE)

# remove any dependency or intermediate build files
tidy:	cleandep clean-versioninfo
	-rm $(OBJ) $(GARBAGE)

#################################

$(TARGET):	$(OBJ) $(EXTDEP)
ifeq ($(SRC_TYPE),c)
	$(CC) $(CXXFLAGS) $(LDFLAGS) $(OBJ) $(LIBPTH) $(LIBLNK) -o $@
else
	$(CXX) $(CXXFLAGS) $(LDFLAGS) $(OBJ) $(LIBPTH) $(LIBLNK) -o $@
endif
ifeq ($(BUILD_TYPE),release)
	$(STRIP) $(TARGET)
endif

###
# extra rules
# example:
#src/parser.c:	src/parser.h

####
# make object files from C source files
obj/%.o:	src/%.c
	$(CC) -c $(CFLAGS) $(CPPFLAGS) $< -o $@

##
# make object files from C++ source files
obj/%.o:	src/%.cc
	$(CXX) -c $(CXXFLAGS) $(CPPFLAGS) $< -o $@

obj/%.o:	src/%.cpp
	$(CXX) -c $(CXXFLAGS) $(CPPFLAGS) $< -o $@

###
# make C files from yacc/bison source
src/%.h src/%.c:	src/%.y
	$(YACC) $(YFLAGS) -d $<
	mv -f y.tab.c $*.c
	mv -f y.tab.h $*.h

###
# make C files from lex/flex source
src/%.c:	src/%.l
	$(LEX) $(LFLAGS) -o$@ $<

###
# make dependencies for our source files
dep/%.d:	src/%.c
	$(CC) -MM $(CPPFLAGS) $< > $@.$$$$; \
		sed 's,\($*\)\.o[ :]*,obj/\1.o $@ : ,g' < $@.$$$$ > $@; \
		rm -f $@.$$$$

dep/%.d:	src/%.cpp
	$(CXX) -MM $(CPPFLAGS) $< > $@.$$$$; \
		sed 's,\($*\)\.o[ :]*,obj/\1.o $@ : ,g' < $@.$$$$ > $@; \
		rm -f $@.$$$$

dep/%.d:	src/%.cc
	$(CXX) -MM $(CPPFLAGS) $< > $@.$$$$; \
		sed 's,\($*\)\.o[ :]*,obj/\1.o $@ : ,g' < $@.$$$$ > $@; \
		rm -f $@.$$$$

####
# pull in the dependency files, but only for 'make $(TARGET)'
####

ifeq ($(MAKECMDGOALS),$(TARGET))
  -include $(DEPFILES)
endif