lsmod.go

/ Aaron Eppert - 2017
// golang wrapper around libkmod with lsmod as an example
//
package main

/*
#cgo pkg-config: libkmod
#include <libkmod.h>
*/
import "C"
import (
	"errors"
	"fmt"
)

func lsmod() error {
	ctx := C.kmod_new(nil, nil)

	if ctx == nil {
		return errors.New("Could not obtain kmod context")
	}

	var list *C.struct_kmod_list
	errVal := C.kmod_module_new_from_loaded(ctx, &list)
	if errVal < 0 {
		C.kmod_unref(ctx)
		return errors.New("Could not get list of modules")
	}

	fmt.Println("Module                  Size  Used by")

	for itr := list; itr != nil; itr = C.kmod_list_next(list, itr) {
		mod := C.kmod_module_get_module(itr)
		name := C.kmod_module_get_name(mod)
		useCount := C.kmod_module_get_refcnt(mod)
		size := C.kmod_module_get_size(mod)

		fmt.Printf("%-19s %8v  %d", C.GoString(name), size, useCount)

		holders := C.kmod_module_get_holders(mod)
		first := true

		if holders != nil {
			for hitr := holders; hitr != nil; hitr = C.kmod_list_next(holders, hitr) {
				hm := C.kmod_module_get_module(hitr)

				if !first {
					fmt.Printf(",")
				} else {
					fmt.Printf(" ")
					first = false
				}

				fmt.Printf("%s", C.GoString(C.kmod_module_get_name(hm)))
				C.kmod_module_unref(hm)
			}
		}

		fmt.Println()
		C.kmod_module_unref_list(holders)
		C.kmod_module_unref(mod)
	}

	C.kmod_module_unref_list(list)
	C.kmod_unref(ctx)

	return nil
}

func main() {
	err := lsmod()
	if err != nil {
		fmt.Println(err)
	}
}