dotcloud/docker

package meminfo

import (
    "unsafe"

    "golang.org/x/sys/windows"
)

var (
    modkernel32 = windows.NewLazySystemDLL("kernel32.dll")

    procGlobalMemoryStatusEx = modkernel32.NewProc("GlobalMemoryStatusEx")
)

// https://msdn.microsoft.com/en-us/library/windows/desktop/aa366589(v=vs.85).aspx
// https://msdn.microsoft.com/en-us/library/windows/desktop/aa366770(v=vs.85).aspx
type memorystatusex struct {
    dwLength                uint32
    dwMemoryLoad            uint32
    ullTotalPhys            uint64
    ullAvailPhys            uint64
    ullTotalPageFile        uint64
    ullAvailPageFile        uint64
    ullTotalVirtual         uint64
    ullAvailVirtual         uint64
    ullAvailExtendedVirtual uint64
}

// readMemInfo retrieves memory statistics of the host system and returns a
// Memory type.
func readMemInfo() (*Memory, error) {
    msi := &memorystatusex{
        dwLength: 64,
    }
    r1, _, _ := procGlobalMemoryStatusEx.Call(uintptr(unsafe.Pointer(msi)))
    if r1 == 0 {
        return &Memory{}, nil
    }
    return &Memory{
        MemTotal:  int64(msi.ullTotalPhys),
        MemFree:   int64(msi.ullAvailPhys),
        SwapTotal: int64(msi.ullTotalPageFile),
        SwapFree:  int64(msi.ullAvailPageFile),
    }, nil
}