Add support for kernel module generation in Makefile. Introduce variables and rules for building, installing, and uninstalling kernel modules.

Author: congwang-mk

src/main.ml

@@ -1005,6 +1005,37 @@ let compile_source input_file output_dir _verbose generate_makefile btf_vmlinux_
 
       let python_flags = if has_python_imports then " $(shell python3-config --cflags) $(shell python3-config --libs --embed 2>/dev/null || python3-config --libs)" else "" in
 
+      (* Check if kernel module was generated *)
+      let has_kernel_module = match kernel_module_code with | Some _ -> true | None -> false in
+      
+      (* Kernel module variables and targets *)
+      let kernel_module_vars = if has_kernel_module then
+        sprintf {|
+# Kernel module files
+KERNEL_MODULE_SRC = %s.mod.c
+KERNEL_MODULE_OBJ = %s.mod.ko|} base_name base_name
+      else "" in
+      
+      let kernel_module_target = if has_kernel_module then " $(KERNEL_MODULE_OBJ)" else "" in
+      
+      let kernel_module_rules = if has_kernel_module then
+        sprintf {|
+# Build kernel module
+$(KERNEL_MODULE_OBJ): $(KERNEL_MODULE_SRC)
+	@echo "Building kernel module..."
+	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
+	
+# Install kernel module (requires root)
+install-module: $(KERNEL_MODULE_OBJ)
+	sudo insmod $(KERNEL_MODULE_OBJ)
+	
+# Remove kernel module (requires root) 
+uninstall-module:
+	sudo rmmod %s || true|} base_name
+      else "" in
+      
+      let kernel_module_clean = if has_kernel_module then " $(KERNEL_MODULE_OBJ) modules.order Module.symvers .*.cmd" else "" in
+      
       let makefile_content = Printf.sprintf {|# Multi-Program eBPF Makefile
 # Generated by KernelScript compiler
 
@@ -1018,7 +1049,7 @@ BPF_INCLUDES = -I/usr/include -I/usr/include/x86_64-linux-gnu
 
 # Userspace compilation flags
 CFLAGS = -Wall -Wextra -O2 -fPIC
-LIBS = -lbpf -lelf -lz
+LIBS = -lbpf -lelf -lz%s
 
 # Object files
 BPF_OBJ = %s.ebpf.o
@@ -1030,7 +1061,7 @@ BPF_SRC = %s.ebpf.c
 USERSPACE_SRC = %s.c
 
 # Default target
-all:%s $(BPF_OBJ) $(SKELETON_H) $(USERSPACE_BIN)
+all:%s $(BPF_OBJ) $(SKELETON_H) $(USERSPACE_BIN)%s
 
 # Compile eBPF C to object file
 $(BPF_OBJ): $(BPF_SRC)
@@ -1044,11 +1075,11 @@ $(SKELETON_H): $(BPF_OBJ)
 # Compile userspace program (link with shared libraries)
 $(USERSPACE_BIN): $(USERSPACE_SRC) $(SKELETON_H)%s
 	$(CC) $(CFLAGS) -o $@ $< $(LIBS)%s%s
-
+%s
 %s
 # Clean generated files
 clean:
-	rm -f $(BPF_OBJ) $(SKELETON_H) $(USERSPACE_BIN)%s
+	rm -f $(BPF_OBJ) $(SKELETON_H) $(USERSPACE_BIN)%s%s
 
 # Build just the eBPF object without skeleton (for testing)
 ebpf-only: $(BPF_OBJ)
@@ -1060,25 +1091,42 @@ run: $(USERSPACE_BIN)
 # Help target
 help:
 	@echo "Available targets:"
-	@echo "  all            - Build eBPF program and userspace coordinator"
+	@echo "  all            - Build eBPF program and userspace coordinator%s"
 	@echo "  ebpf-only      - Build just the eBPF object file"
-	@echo "  clean          - Clean all generated files"
+%s	@echo "  clean          - Clean all generated files"
 	@echo "  run            - Run the userspace program (requires sudo)"
 
-.PHONY: all clean run ebpf-only help
-|} base_name base_name base_name base_name base_name 
-       shared_lib_deps shared_lib_deps
+.PHONY: all clean run ebpf-only help%s
+|} kernel_module_vars base_name base_name base_name base_name base_name 
+       shared_lib_deps kernel_module_target shared_lib_deps
        (if shared_lib_targets = "" then "" else (" " ^ String.concat " " (List.map (fun import -> "./" ^ import.Import_resolver.module_name ^ ".so") ks_imports)))
        python_flags
+       kernel_module_rules 
        shared_lib_rules 
-       (if shared_lib_targets = "" then "" else (" " ^ shared_lib_targets)) in
+       (if shared_lib_targets = "" then "" else (" " ^ shared_lib_targets)) 
+       kernel_module_clean
+       (if has_kernel_module then " and kernel module" else "")
+       (if has_kernel_module then sprintf {|	@echo "  install-module - Install kernel module (requires root)"
+	@echo "  uninstall-module - Remove kernel module (requires root)"
+|} else "")
+       (if has_kernel_module then " install-module uninstall-module" else "") in
 
       let makefile_path = actual_output_dir ^ "/Makefile" in
       let oc = open_out makefile_path in
       output_string oc makefile_content;
       close_out oc;
 
-      Printf.printf "📄 Generated Makefile: %s/Makefile\n" actual_output_dir
+      Printf.printf "📄 Generated Makefile: %s/Makefile\n" actual_output_dir;
+      
+      (* Generate Kbuild file if kernel module exists *)
+      if has_kernel_module then (
+        let kbuild_content = sprintf "obj-m += %s.mod.o\n" base_name in
+        let kbuild_path = actual_output_dir ^ "/Kbuild" in
+        let kbuild_oc = open_out kbuild_path in
+        output_string kbuild_oc kbuild_content;
+        close_out kbuild_oc;
+        Printf.printf "📄 Generated Kbuild: %s/Kbuild\n" actual_output_dir
+      )
     );
 
       Printf.printf "\n✨ Compilation completed successfully!\n";