From f16948640707400e1e3d2246f5483135d4801701 Mon Sep 17 00:00:00 2001
From: Jan De Dobbeleer <jan.de.dobbeleer@gmail.com>
Date: Sat, 27 Feb 2021 18:53:44 +0100
Subject: [PATCH] fix: windows arm support

---
 process/process_windows_arm64.go | 104 +++++++++++++++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 process/process_windows_arm64.go

diff --git a/process/process_windows_arm64.go b/process/process_windows_arm64.go
new file mode 100644
index 00000000..ddaf1954
--- /dev/null
+++ b/process/process_windows_arm64.go
@@ -0,0 +1,104 @@
+//go:build windows && arm64
+// +build windows,arm64
+
+package process
+
+import (
+	"errors"
+	"syscall"
+	"unsafe"
+
+	"github.com/shirou/gopsutil/internal/common"
+)
+
+type PROCESS_MEMORY_COUNTERS struct {
+	CB                         uint32
+	PageFaultCount             uint32
+	PeakWorkingSetSize         uint32
+	WorkingSetSize             uint32
+	QuotaPeakPagedPoolUsage    uint32
+	QuotaPagedPoolUsage        uint32
+	QuotaPeakNonPagedPoolUsage uint32
+	QuotaNonPagedPoolUsage     uint32
+	PagefileUsage              uint32
+	PeakPagefileUsage          uint32
+}
+
+func queryPebAddress(procHandle syscall.Handle, is32BitProcess bool) (uint64, error) {
+	if is32BitProcess {
+		//we are on a 32-bit process reading an external 32-bit process
+		var info processBasicInformation32
+
+		ret, _, _ := common.ProcNtQueryInformationProcess.Call(
+			uintptr(procHandle),
+			uintptr(common.ProcessBasicInformation),
+			uintptr(unsafe.Pointer(&info)),
+			uintptr(unsafe.Sizeof(info)),
+			uintptr(0),
+		)
+		if int(ret) >= 0 {
+			return uint64(info.PebBaseAddress), nil
+		}
+	} else {
+		//we are on a 32-bit process reading an external 64-bit process
+		if common.ProcNtWow64QueryInformationProcess64.Find() == nil { //avoid panic
+			var info processBasicInformation64
+
+			ret, _, _ := common.ProcNtWow64QueryInformationProcess64.Call(
+				uintptr(procHandle),
+				uintptr(common.ProcessBasicInformation),
+				uintptr(unsafe.Pointer(&info)),
+				uintptr(unsafe.Sizeof(info)),
+				uintptr(0),
+			)
+			if int(ret) >= 0 {
+				return info.PebBaseAddress, nil
+			}
+		}
+	}
+
+	//return 0 on error
+	return 0, errors.New("could not query PEB address")
+}
+
+func readProcessMemory(h syscall.Handle, is32BitProcess bool, address uint64, size uint) []byte {
+	if is32BitProcess {
+		var read uint
+
+		buffer := make([]byte, size)
+
+		ret, _, _ := common.ProcNtReadVirtualMemory.Call(
+			uintptr(h),
+			uintptr(address),
+			uintptr(unsafe.Pointer(&buffer[0])),
+			uintptr(size),
+			uintptr(unsafe.Pointer(&read)),
+		)
+		if int(ret) >= 0 && read > 0 {
+			return buffer[:read]
+		}
+	} else {
+		//reading a 64-bit process from a 32-bit one
+		if common.ProcNtWow64ReadVirtualMemory64.Find() == nil { //avoid panic
+			var read uint64
+
+			buffer := make([]byte, size)
+
+			ret, _, _ := common.ProcNtWow64ReadVirtualMemory64.Call(
+				uintptr(h),
+				uintptr(address&0xFFFFFFFF), //the call expects a 64-bit value
+				uintptr(address>>32),
+				uintptr(unsafe.Pointer(&buffer[0])),
+				uintptr(size), //the call expects a 64-bit value
+				uintptr(0),    //but size is 32-bit so pass zero as the high dword
+				uintptr(unsafe.Pointer(&read)),
+			)
+			if int(ret) >= 0 && read > 0 {
+				return buffer[:uint(read)]
+			}
+		}
+	}
+
+	//if we reach here, an error happened
+	return nil
+}