swap.go

package main

/*
#include <sys/types.h>
#include <sys/swap.h>
#include <unistd.h>
*/
import "C"

import (
	"fmt"
	"unsafe"

	"github.com/davecgh/go-spew/spew"
)

type Swapent struct {
	se_dev      C.dev_t
	se_flags    int
	se_nblks    int
	se_inuse    int
	se_priority int
	sw_path     []byte
	//	se_path     [C.PATH_MAX]C.char // not quite right but we don't use this field
}

func main() {
	swap()
}

func swap() error {
	nswap := C.swapctl(C.SWAP_NSWAP, unsafe.Pointer(uintptr(0)), 0)

	// If there are no swap devices, nothing to do here.
	if nswap == 0 {
		return nil
	}

	swdev := make([]Swapent, nswap)
	spew.Dump(swdev)

	fmt.Printf("nswap: %v\n", nswap)

	rnswap := C.swapctl(C.SWAP_STATS, unsafe.Pointer(&swdev), nswap)
	if rnswap == 0 {
		return nil
	}

	fmt.Println(swdev[0].se_nblks)
	for i := 0; i < int(nswap); i++ {
		spew.Dump(swdev)
		//		if swdev[i].se_flags&C.SWF_ENABLE == 1 {
		//
		//		}
	}

	return nil
}

/*
static int
swapmode(int *used, int *total)
{
	struct swapent *swdev;
	int nswap, rnswap, i;

	nswap = swapctl(SWAP_NSWAP, 0, 0);
	if (nswap == 0)
		return 0;

	swdev = calloc(nswap, sizeof(*swdev));
	if (swdev == NULL)
		return 0;

	rnswap = swapctl(SWAP_STATS, swdev, nswap);
	if (rnswap == -1) {
		free(swdev);
		return 0;
	}

	*total = *used = 0;
	for (i = 0; i < nswap; i++) {
		if (swdev[i].se_flags & SWF_ENABLE) {
			*used += (swdev[i].se_inuse / (1024 / DEV_BSIZE));
			*total += (swdev[i].se_nblks / (1024 / DEV_BSIZE));
		}
	}
	free(swdev);
	return 1;
}
*/