chore: remove depend of gopsutil

component/memory/memory_freebsd.go

@@ -0,0 +1,97 @@
+package memory
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+const (
+	CTLKern          = 1
+	KernProc         = 14
+	KernProcPID      = 1
+)
+
+func CallSyscall(mib []int32) ([]byte, uint64, error) {
+	mibptr := unsafe.Pointer(&mib[0])
+	miblen := uint64(len(mib))
+
+	// get required buffer size
+	length := uint64(0)
+	_, _, err := unix.Syscall6(
+		unix.SYS___SYSCTL,
+		uintptr(mibptr),
+		uintptr(miblen),
+		0,
+		uintptr(unsafe.Pointer(&length)),
+		0,
+		0)
+	if err != 0 {
+		var b []byte
+		return b, length, err
+	}
+	if length == 0 {
+		var b []byte
+		return b, length, err
+	}
+	// get proc info itself
+	buf := make([]byte, length)
+	_, _, err = unix.Syscall6(
+		unix.SYS___SYSCTL,
+		uintptr(mibptr),
+		uintptr(miblen),
+		uintptr(unsafe.Pointer(&buf[0])),
+		uintptr(unsafe.Pointer(&length)),
+		0,
+		0)
+	if err != 0 {
+		return buf, length, err
+	}
+
+	return buf, length, nil
+}
+
+func parseKinfoProc(buf []byte) (KinfoProc, error) {
+	var k KinfoProc
+	br := bytes.NewReader(buf)
+	err := binary.Read(br, binary.LittleEndian, &k)
+	return k, err
+}
+
+func getKProc(pid int32) (*KinfoProc, error) {
+	mib := []int32{CTLKern, KernProc, KernProcPID, pid}
+
+	buf, length, err := CallSyscall(mib)
+	if err != nil {
+		return nil, err
+	}
+	if length != sizeOfKinfoProc {
+		return nil, errors.New("unexpected size of KinfoProc")
+	}
+
+	k, err := parseKinfoProc(buf)
+	if err != nil {
+		return nil, err
+	}
+	return &k, nil
+}
+
+func GetMemoryInfo(pid int32) (*MemoryInfoStat, error) {
+	k, err := getKProc(pid)
+	if err != nil {
+		return nil, err
+	}
+	v, err := unix.Sysctl("vm.stats.vm.v_page_size")
+	if err != nil {
+		return nil, err
+	}
+	pageSize := binary.LittleEndian.Uint16([]byte(v))
+
+	return &MemoryInfoStat{
+		RSS: uint64(k.Rssize) * uint64(pageSize),
+		VMS: uint64(k.Size),
+	}, nil
+}