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Code: Select all

compile src/test1.c to obj/test1.o if out of date:

compile($src,$trg){
	exec([$CC $CFLAGS -c $src -o $trg]);
};

default(){
	if older("obj/test1.o","src/test1.c") { //if test1.o is older than test1.c
		compile("src/test1.c","obj/test1.o");
	} else {
		exec("echo \"Target is up to date\" ");
	}
}

..continuation to also link obj/test1.o to test1

link($objs,$trg){
	exec([$CC $LDFLAGS -o $trg $objs]);
}

default(){
	string $objs;
	if older("obj/test1.o","src/test1.c") { //if test1.o is older than test1.c
		compile("src/test1.c","obj/test1.o");
	} else {
		exec("echo \"Target is up to date\" ");
	}
	$objs=concat($objs,"obj/test1.o ");
	$objs=concat($objs,"objs/other_objects.o ");
	link($objs,"bin/test1");
	
}

complicated example to compile all .c files in src/ to .o files in objs/
and then link them all(only if out of date though) (using compile and link from before)
for example, it contains files: main.c test.c foo.c no.f


default(){
	string $cfiles;
	string $objfiles;
	cd("src/");
	$cfiles=file_glob("*.c"); //this is so we get main.c not src/main.c
	cd("..");
	for_each($cfiles," ") = $this_file{ //for each element in cfiles seperated by " ". Put current element in this_file
		string $this_obj;
		$this_obj=glob_replace($this_file,"*.c","*.o"); //replace main.c with main.o, *.c with *.o
		$this_obj=concat("objs/",$this_obj); //make it so it's objs/main.o
		$this_file=concat("src/",$this_file); //make it so it's src/main.c
		if(older($this_obj,$this_file)){
			compile($this_file,$this_obj);
		}
		$objfiles=concat($objfiles,$this_obj);
	}
	link($objfiles,"bin/a.out");
}

Code: Select all

Everything for this is quite easy.. Ok. More complicated example(this might take me a while to write lol)
We have a kernel. It can be compiled for i386, ppc, or amd64. It all depends on an environmental variable ARCH
Source files are in src/
src has all system independent files in it. Also, it has i386, ppc, and amd64 directories which have the
arch. dependent code. For each target, they all need the system independent and they need only their
arch. dependent files. include/ has some common header files to all of them. src/ has some header files as
does all of the arch. directories. 
When compiled, the files need to not interfere with each other, so they must go in obj/ obj/i386 etc
When linked to output file, they need to go to bin/kernel_ARCH

Let's get hacking.

#include <common_funcs.jfi> //source of compile and link from above

import $ARCH; //import from environmental variable.
string $objs;
string $srcs;
string $headers; //declare all of these global variables.

get_arch_sources(){ //get arch srcs and headers
	cd("src");
	$srcs=concat($srcs,file_glob([$ARCH/*.c]));
	$headers=concat($headers,file_glob([$ARCH/*.h]));
	cd("..");
}

get_common_sources(){ //get common srcs and headers
	cd("src");
	$srcs=concat($srcs,file_glob("*.c"));
	$headers=concat($headers,file_glob("*.h"));
	cd("..");
}

compile_async($src,$trg){
   exec_async([$CC $CFLAGS -c $src -o $trg]); //executes a file asynchronously. We don't wait on the process to finish.
};

default(){
	bool $need_compile;
	$need_compile=false;
	if(notequal($ARCH,"i386") | notequal($ARCH,"amd64") | notequal($ARCH,"ppc")){
		exec([echo "$ARCH is not a supported target"]);
	}
	get_common_sources();
	get_arch_sources();
	for_each($srcs," ") = $this_file{ //for each element in cfiles separated by " ". Put current element in this_file
		string $this_obj;
		$this_obj=glob_replace($this_file,"*.c","*.o"); //replace main.c with main.o, *.c with *.o
		$this_obj=concat("objs/",$this_obj); //make it so it's objs/main.o
		$this_file=concat("src/",$this_file); //make it so it's src/main.c
		for_each($headers," ") = $this_header){
			if(older($this_obj,$this_file) OR older($this_obj,$this_header)){
				$need_compile=true;
			}
		}
		if($need_compile){
			compile_async($this_file,$this_obj);
		}
		$objs=concat($objs,$this_obj);
		
		
	}
	wait_async(); //This will wait on all async processes to finish.
	//This is so everything is compiled before we link it.
	string $outname;
	$outname=concat("bin/kernel_",$ARCH);
	link($objs,$outname);
}