String manipulation in makefiles - makefile

I've replaced my many .sh files from my previous question with a makefile, of sorts. I don't know much about makefiles, admittedly, but this seems to work:
MainPackage=jnitest
Main=SimpleJNITest
cFileName=rtm_simple
targetDir=classes
libDir=lib
srcDir=src
jdkDir="/home/user/local/java/jdk1.7.0_65"
java="$(jdkDir)/bin/java"
javah="$(jdkDir)/bin/javah"
javac="$(jdkDir)/bin/javac"
JAVAC_FLAGS=-d "$(targetDir)" -sourcepath "$(srcDir)" -cp "$(targetDir):$(libDir)/*"
JAVAH_FLAGS=-d "$(ccodeDir)" -cp "$(targetDir)" -jni
JAVA_FLAGS=-Djava.library.path="$(LD_LIBRARY_PATH):$(libDir)" -cp "$(targetDir):$(libDir)/*"
ccodeDir=$(srcDir)/ccode
CC=gcc
CC_FLAGS=-g -shared -fpic -I "$(jdkDir)/include" -I "$(jdkDir)/include/linux"
cFile="$(ccodeDir)/$(cFileName).c"
soFile="$(libDir)/lib$(cFileName).so"
dirs:
mkdir -p "$(targetDir)"
mkdir -p "$(libDir)"
java: dirs
$(javac) $(JAVAC_FLAGS) "$(srcDir)/$(MainPackage)/$(Main).java"
header:
$(javah) $(JAVAH_FLAGS) "$(MainPackage).$(Main)"
c:
$(CC) $(CC_FLAGS) $(cFile) -o $(soFile)
all:
$(MAKE) java
$(MAKE) header
$(MAKE) c
run:
$(java) $(JAVA_FLAGS) "$(MainPackage).$(Main)"
clean:
rm -rf classes
rm -rf lib
rm -f $(ccodeDir)/$(MainPackage)_$(Main).h
My problem, now, lies with MainPackage=jnitest.
So long as MainPackage is a single word, everything is fine.
However, when it is not, I'll be needing it once in slash notation for
$(javac) $(JAVAC_FLAGS) "$(srcDir)/$(MainPackage)/$(Main).java"
and once in dot notation for
$(java) $(JAVA_FLAGS) "$(MainPackage).$(Main)"
In bash, you could do something like
MainPackage_slashed=$(echo "$MainPackage" | tr '.' '/')
How do I insert one such transformation into a makefile?

You're looking for the subst function, see the GNU make manual.
Example:
foo=x.y.z
bar=$(subst .,/,$(foo))
$(info $(bar))
prints x/y/z.

You will need to use shell function in your Makefile like this:
MainPackage_slashed := $(shell echo "$(MainPackage)" | tr '.' '/')

Related

make rule for files in subdirectory with the working directory set to this subdirectory

I have some source files in a subdirectory:
$ ls subdir
foo.x bar.x other_file
Now I want to create a rule like
subdir/%.y: subdir/%.x
cmd $< -a option -o $#
just that cmd needs the working directory set to subdir.
I want something that if subdir/bar.y is required it is generated like
cd subdir && cmd bar.x -a option -o bar.y
Is there for example a way to say $< and $# but without the leading subdir/?
If you're using GNU make, you can use $(notdir $<) and $(notdir $#) to get the filenames without a directory. And you can use $(dir $#) to get the directory part:
subdir/%.y: subdir/%.x
cd $(dir $#) && cmd $(notdir $<) -a option -o $(notdir $#)
Or hardcode subdir, if you prefer.
You can use the F or D suffix for the file and directory part respectively.
subdir/%.y: subdir/%.x
cd $(#D) && cmd $(<F) -a option -o $(#F)
See the manual for details.
What about using $(patsubst) ?
subdir/%.y: subdir/%.x
cd subdir && cmd $(patsubst subdir/%,%,$<) -a option -o $(patsubst subdir/%,%,$#)
Or, the equivalent but simpler:
subdir/%.y: subdir/%.x
cd subdir && cmd $(<:subdir/%=%) -a option -o $(#:subdir/%=%)

Expanding dependency's dirname for Makefile wildcard

Following on from Build script to Makefile, which lives in this upstream location. I want to include the Javascript examples that are included into this generated HTML document as dependencies.
INFILES = $(shell find . -name "index.src.html")
OUTFILES = $(INFILES:.src.html=.html)
TEMP:= $(shell mktemp -u /tmp/specs.XXXXXX)
all: $(OUTFILES)
# Problem line:
%.html: %.src.html $(wildcard contacts/*js)
#echo Dependencies: $^
cd $(#D) && m4 -PEIinc index.src.html > $(TEMP)
anolis --max-depth=3 $(TEMP) $#
rm -f $(TEMP)
clean:
rm -f $(OUTFILES)
PHONY: all clean
I want $(wildcard contacts/*js) to be $(wildcard $(#D)/*js) or $(wildcard $(dirname %)/*js), but nothing I've tried works. There must be some sort of keyword to get the parent directory of the target or dependency so I can reference the javascript dependencies.
AFAIK, using $(#D) and other automatic variables inside list of prerequisites can only be achieved using secondary expansion feature of GNU Make.
Thus, your problem probably can be solved as follows:
.SECONDEXPANSION:
%.html: %.src.html $$(wildcard $$(#D)/*js)
However, I'm not sure whether it will work with pattern rules.

Setting target variable for the name of the makefile from a subdirectory

How can I have the variable for $(MAKEFILE) be defined during target execution?
Basically I have a few make files in subdirectories that are named for a specific platform "Makefile.aix" and just Makefile in all other directories. I would like to set a variable for $(MAKEFILE) that gets defined in each subdirectory. Code would look something like this.
MAKEFILE = Makefile
SUBDIR = ./sub ./sub2
ifneq ($(wildcard Makefile),)
MAKEFILE = Makefile
else
MAKEFILE = Makefile.$(PLATFORM)
endif
all:;
#for i in $(SUBDIR);\
do (\
echo Making $$i ...;\
cd $$i;\
make -f $(MAKEFILE)\
); done
Is there just one Makefile.$(PLATFORM) in each subdirectory, or are there several, for different platforms?
In the first case, you could do something like this:
SUBDIR = ./sub ./sub2
define script
cd $(1); \
$(MAKE) -f Makefile*
endef
all:
$(foreach dir, $(SUBDIR), $(call script,$(dir)))
(The empty line inside the define is significant. It can be omitted, if you add a semicolon at the end of the line $(MAKE) ..., leading to one long command line, containing the commands for all directories, which will then be executed in one chunk.)
An alternative script would be (just a matter of personal preference which you like better):
define script
$(MAKE) -C $(1) -f $(notdir $(wildcard $(1)/Makefile*))
endef
If there are several Makefile.$(PLATFORM) files in a directory it becomes more difficult. I'll have to think about that one some more.
UPDATE: In response to your comment, something like this should work:
define script
$(MAKE) -C $(1) -f $(notdir $(wildcard $(1)/Makefile $(1)/Makefile.$(PLATFORM)))
endef
Following your logic, I'd propose update do () section with:
do (\
echo Making $$i ...;\
cd $$i;\
if [ -f Makefile.$(PLATFORM) ] \
then\
make -f Makefile.$(PLATFORM) \
else\
make -f Makefile\
fi\
); done
This is actually not a make style, but I can't suggest anything better without specific of your project
You can do most of this, including the loop over directories, using GNU make's built-in functions. Put the following in a central place, say $(TOP_DIR)/mk/subdir.mk:
makefile-for-dir = \
$(if $(wildcard $(1)/Makefile),Makefile,Makefile.$(PLATFORM))
make-recursive = \
$(foreach _d,$(1),$(MAKE) -C $(_d) -f $(call makefile-for-dir,$(_d)) && ) :
In each makefile that start recursive makes, use
include $(TOP_DIR)/mk/subdir.mk
SUBDIRS = dir1 dir2 dir3
.PHONY: all
all:
+#$(call make-recursive,$(SUBDIRS))

Using sed in a makefile; how to escape variables?

I am writing a generic makefile to build static libraries. It seems to work well so far, except for the line calling sed:
# Generic makefile to build a static library
ARCH = linux
CFLAGS = -O3 -Wall
SOURCES = src
BUILD_DIR = build/$(ARCH)
TARGET = $(BUILD_DIR)/libz.a
CFILES = $(foreach dir,$(SOURCES),$(wildcard $(dir)/*.c))
OBJECTS = $(addprefix $(BUILD_DIR)/,$(CFILES:.c=.o))
# Pull in the dependencies if they exist
# http://scottmcpeak.com/autodepend/autodepend.html
-include $(OBJECTS:.o=.dep)
default: create-dirs $(TARGET)
$(TARGET): $(OBJECTS)
$(AR) -rc $(TARGET) $^
$(BUILD_DIR)/%.o: %.c
$(CC) $(CFLAGS) -c $< -o $#
$(CC) -M $(CFLAGS) $*.c > $(BUILD_DIR)/$*.tmp
sed s/.*:/$(BUILD_DIR)\\/$*.o:/ $(BUILD_DIR)/$*.tmp > $(BUILD_DIR)/$*.dep
#rm $(BUILD_DIR)/$*.tmp
.PHONY: create-dirs
create-dirs:
#for p in $(SOURCES); do mkdir -p $(BUILD_DIR)/$$p; done
.PHONY: clean
clean:
rm -fr $(BUILD_DIR)
sed is used to replace the path/name of the object file with the full path of where the object actually is. e.g. 'src/foo.o:' is replaced with 'build/linux/src/foo.o:' in this example.
$(BUILD_DIR) and $* in the replacement string both contain forward slashes when expanded - how do I pass them to sed?
Note: This might have been answered here before, but I am so far unable to apply those answers to my specific problem!
You can use anything else than forward slashes as separator in sed. E.g. sed s~foo~bar~g
You can use double quotes " (at least in the shell), and variables will still be expanded: echo "Hello $PLANET"
If you want the path to expand into a file you use
sed -i "s/TO_REPLACE/$(subst, /,\/,${PATH_VARIABLE})/g" filename.txt
If your variable PATH_VARIABLE looked like /opt/path/user/home/etc
it will now inflate to:
\ /opt\ /path\ /user\ /home\ /etc
This should allow sed to insert the ' / ' correctly.
-Matt

how to prevent "directory already exists error" in a makefile when using mkdir

I need to generate a directory in my makefile and I would like to not get the "directory already exists error" over and over even though I can easily ignore it.
I mainly use mingw/msys but would like something that works across other shells/systems too.
I tried this but it didn't work, any ideas?
ifeq (,$(findstring $(OBJDIR),$(wildcard $(OBJDIR) )))
-mkdir $(OBJDIR)
endif
Looking at the official make documentation, here is a good way to do it:
OBJDIR := objdir
OBJS := $(addprefix $(OBJDIR)/,foo.o bar.o baz.o)
$(OBJDIR)/%.o : %.c
$(COMPILE.c) $(OUTPUT_OPTION) $<
all: $(OBJS)
$(OBJS): | $(OBJDIR)
$(OBJDIR):
mkdir -p $(OBJDIR)
You should see here the usage of the | pipe operator, defining an order only prerequisite.
Meaning that the $(OBJDIR) target should be existent (instead of more recent) in order to build the current target.
Note that I used mkdir -p. The -p flag was added compared to the example of the docs.
See other answers for another alternative.
On UNIX Just use this:
mkdir -p $(OBJDIR)
The -p option to mkdir prevents the error message if the directory exists.
You can use the test command:
test -d $(OBJDIR) || mkdir $(OBJDIR)
Here is a trick I use with GNU make for creating compiler-output directories. First define this rule:
%/.d:
mkdir -p $(#D)
touch $#
Then make all files that go into the directory dependent on the .d file in that directory:
obj/%.o: %.c obj/.d
$(CC) $(CFLAGS) -c -o $# $<
Note use of $< instead of $^.
Finally prevent the .d files from being removed automatically:
.PRECIOUS: %/.d
Skipping the .d file, and depending directly on the directory, will not work, as the directory modification time is updated every time a file is written in that directory, which would force rebuild at every invocation of make.
If having the directory already exist is not a problem for you, you could just redirect stderr for that command, getting rid of the error message:
-mkdir $(OBJDIR) 2>/dev/null
Inside your makefile:
target:
if test -d dir; then echo "hello world!"; else mkdir dir; fi
On Windows
if not exist "$(OBJDIR)" mkdir $(OBJDIR)
On Unix | Linux
if [ ! -d "$(OBJDIR)" ]; then mkdir $(OBJDIR); fi
ifeq "$(wildcard $(MY_DIRNAME) )" ""
-mkdir $(MY_DIRNAME)
endif
$(OBJDIR):
mkdir $#
Which also works for multiple directories, e.g..
OBJDIRS := $(sort $(dir $(OBJECTS)))
$(OBJDIRS):
mkdir $#
Adding $(OBJDIR) as the first target works well.
It works under mingw32/msys/cygwin/linux
ifeq "$(wildcard .dep)" ""
-include $(shell mkdir .dep) $(wildcard .dep/*)
endif
If you explicitly ignore the return code and dump the error stream then your make will ignore the error if it occurs:
mkdir 2>/dev/null || true
This should not cause a race hazard in a parallel make - but I haven't tested it to be sure.
A little simpler than Lars' answer:
something_needs_directory_xxx : xxx/..
and generic rule:
%/.. : ;#mkdir -p $(#D)
No touch-files to clean up or make .PRECIOUS :-)
If you want to see another little generic gmake trick, or if you're interested in non-recursive make with minimal scaffolding, you might care to check out Two more cheap gmake tricks and the other make-related posts in that blog.

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