Read kMDItemWhereFroms in Go

wherefroms.go

package main

/*
#include <stdlib.h>
#include <sys/xattr.h>
*/
import "C"

import (
	"fmt"
	"os"
	"unsafe"

	"howett.net/plist"
)

var key = C.CString("com.apple.metadata:kMDItemWhereFroms")

func main() {
	if len(os.Args) != 2 {
		fmt.Printf("Usage: %s <path>\n", os.Args[0])
		return
	}
	path := os.Args[1]
	cpath := C.CString(path)
	defer C.free(unsafe.Pointer(cpath))
	nbytes, err := C.getxattr(cpath, key, nil, 0, 0, 0)
	if nbytes == -1 {
		fmt.Printf("getxattr failed: %s\n", err)
		return
	}
	if nbytes == 0 {
		fmt.Printf("No data\n")
		return
	}
	fmt.Printf("Got %d bytes\n", nbytes)
	mem := make([]byte, nbytes)
	size2, err := C.getxattr(cpath, key, unsafe.Pointer(&mem[0]), C.size_t(nbytes), 0, 0)

	if size2 != nbytes {
		fmt.Printf("Size mismatch\n")
		return
	}

	fmt.Printf("Got '%s'\n", mem)

	var urls []string
	format, err := plist.Unmarshal(mem, &urls)
	fmt.Printf("Result format:%d err:%v urls:%+v\n", format, err, urls)

}