windows_exporter/sysinfoapi/sysinfoapi.go
Ben Ridley 71054ac429 Replace the CS collector with native WinAPI calls to sysinfoapi
Signed-off-by: Ben Ridley <benridley29@gmail.com>
2021-03-18 16:18:47 -07:00

113 lines
3.6 KiB
Go

// Copyright 2020 Prometheus Team
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package sysinfoapi wraps some WinAPI sysinfoapi functions used by the exporter to produce metrics.
// It is fairly opinionated for the exporter's internal use, and is not intended to be a
// generic wrapper for the WinAPI's sysinfoapi.
package sysinfoapi
import (
"unicode/utf16"
"unsafe"
"golang.org/x/sys/windows"
)
// WinProcInfo is a wrapper for
type WinProcInfo struct {
WReserved uint16
WProcessorArchitecture uint16
}
// WinSystemInfo is a wrapper for LPSYSTEM_INFO
type WinSystemInfo struct {
Arch WinProcInfo
DwPageSize uint32
LpMinimumApplicationAddress *byte
LpMaximumApplicationAddress *byte
DwActiveProcessorMask *uint32
DwNumberOfProcessors uint32
DwProcessorType uint32
DwAllocationGranularity uint32
WProcessorLevel uint16
WProcessorRevision uint16
}
// WinComputerNameFormat is a wrapper for COMPUTER_NAME_FORMAT
type WinComputerNameFormat int
// Definitions for WinComputerNameFormat constants
const (
ComputerNameNetBIOS WinComputerNameFormat = iota
ComputerNameDNSHostname
ComputerNameDNSDomain
ComputerNameDNSFullyQualified
ComputerNamePhysicalNetBIOS
ComputerNamePhysicalDNSHostname
ComputerNamePhysicalDNSDomain
ComputerNamePhysicalDNSFullyQualified
ComputerNameMax
)
// WinMemoryStatus is a wrapper for LPMEMORYSTATUSEX
type WinMemoryStatus struct {
dwLength uint32
dwMemoryLoad uint32
ullTotalPhys uint64
ullAvailPhys uint64
ullTotalPageFile uint64
ullAvailPageFile uint64
ullTotalVirtual uint64
ullAvailVirtual uint64
ullAvailExtendedVirtual uint64
}
var (
kernel32 = windows.NewLazySystemDLL("kernel32.dll")
procGetSystemInfo = kernel32.NewProc("GetSystemInfo")
procGlobalMemoryStatusEx = kernel32.NewProc("GlobalMemoryStatusEx")
procGetComputerNameExW = kernel32.NewProc("GetComputerNameExW")
)
// GetNumLogicalProcessors returns the number of logical processes provided by sysinfoapi's GetSystemInfo function.
func GetNumLogicalProcessors() int {
var sysInfo WinSystemInfo
pInfo := uintptr(unsafe.Pointer(&sysInfo))
procGetSystemInfo.Call(pInfo)
return int(sysInfo.DwNumberOfProcessors)
}
// GetPhysicalMemory returns the system's installed physical memory provided by sysinfoapi's GlobalMemoryStatusEx function.
func GetPhysicalMemory() (int, error) {
var wm WinMemoryStatus
wm.dwLength = (uint32)(unsafe.Sizeof(wm))
r1, _, err := procGlobalMemoryStatusEx.Call(uintptr(unsafe.Pointer(&wm)))
if r1 != 1 {
return 0, err
}
return int(wm.ullTotalPhys), nil
}
// GetComputerName provides the requested computer name provided by sysinfoapi's GetComputerNameEx function.
func GetComputerName(f WinComputerNameFormat) (string, error) {
size := 4096
var buffer [4096]uint16
r1, _, err := procGetComputerNameExW.Call(uintptr(f), uintptr(unsafe.Pointer(&buffer)), uintptr(unsafe.Pointer(&size)))
if r1 == 0 {
return "", err
}
bytes := buffer[0:size]
out := utf16.Decode(bytes)
return string(out), nil
}