From 903277ce2f1501d31ea8fb03731a30b382ddd1a5 Mon Sep 17 00:00:00 2001
From: WAKAYAMA Shirou <shirou.faw@gmail.com>
Date: Wed, 4 May 2016 22:39:44 +0900
Subject: [PATCH] [process]windows: implement process.MemoryInfo (but no swap)

---
 process/process_windows.go       | 45 ++++++++++++++++++++++++++++++++++++++--
 process/process_windows_386.go   | 16 ++++++++++++++
 process/process_windows_amd64.go | 16 ++++++++++++++
 3 files changed, 75 insertions(+), 2 deletions(-)
 create mode 100644 process/process_windows_386.go
 create mode 100644 process/process_windows_amd64.go

diff --git a/process/process_windows.go b/process/process_windows.go
index 3176cde..e5852ae 100644
--- a/process/process_windows.go
+++ b/process/process_windows.go
@@ -23,6 +23,11 @@ const (
 	MaxPathLength = 260
 )
 
+var (
+	modpsapi                 = syscall.NewLazyDLL("psapi.dll")
+	procGetProcessMemoryInfo = modpsapi.NewProc("GetProcessMemoryInfo")
+)
+
 type SystemProcessInformation struct {
 	NextEntryOffset   uint64
 	NumberOfThreads   uint64
@@ -75,7 +80,7 @@ type Win32_Process struct {
 		PeakPageFileUsage     uint32
 		PeakVirtualSize       uint64
 		PeakWorkingSetSize    uint32
-		PrivatePageCount      uint64
+			PrivatePageCount      uint64
 		ReadOperationCount    uint64
 		ReadTransferCount     uint64
 		Status                *string
@@ -234,7 +239,17 @@ func (p *Process) CPUAffinity() ([]int32, error) {
 	return nil, common.ErrNotImplementedError
 }
 func (p *Process) MemoryInfo() (*MemoryInfoStat, error) {
-	return nil, common.ErrNotImplementedError
+	mem, err := getMemoryInfo(p.Pid)
+	if err != nil {
+		return nil, err
+	}
+
+	ret := &MemoryInfoStat{
+		RSS: mem.WorkingSetSize,
+		VMS: mem.PagefileUsage,
+	}
+
+	return ret, nil
 }
 func (p *Process) MemoryInfoEx() (*MemoryInfoExStat, error) {
 	return nil, common.ErrNotImplementedError
@@ -355,3 +370,29 @@ func getProcInfo(pid int32) (*SystemProcessInformation, error) {
 
 	return &sysProcInfo, nil
 }
+
+func getMemoryInfo(pid int32) (PROCESS_MEMORY_COUNTERS, error) {
+	var mem PROCESS_MEMORY_COUNTERS
+	c, err := syscall.OpenProcess(syscall.PROCESS_QUERY_INFORMATION, false, uint32(pid))
+	if err != nil {
+		return mem, err
+	}
+	defer syscall.CloseHandle(c)
+	if err := getProcessMemoryInfo(c, &mem); err != nil {
+		return mem, err
+	}
+
+	return mem, err
+}
+
+func getProcessMemoryInfo(h syscall.Handle, mem *PROCESS_MEMORY_COUNTERS) (err error) {
+	r1, _, e1 := syscall.Syscall(procGetProcessMemoryInfo.Addr(), 3, uintptr(h), uintptr(unsafe.Pointer(mem)), uintptr(unsafe.Sizeof(*mem)))
+	if r1 == 0 {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
diff --git a/process/process_windows_386.go b/process/process_windows_386.go
new file mode 100644
index 0000000..68f3153
--- /dev/null
+++ b/process/process_windows_386.go
@@ -0,0 +1,16 @@
+// +build windows
+
+package process
+
+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
+}
diff --git a/process/process_windows_amd64.go b/process/process_windows_amd64.go
new file mode 100644
index 0000000..df286df
--- /dev/null
+++ b/process/process_windows_amd64.go
@@ -0,0 +1,16 @@
+// +build windows
+
+package process
+
+type PROCESS_MEMORY_COUNTERS struct {
+	CB                         uint32
+	PageFaultCount             uint32
+	PeakWorkingSetSize         uint64
+	WorkingSetSize             uint64
+	QuotaPeakPagedPoolUsage    uint64
+	QuotaPagedPoolUsage        uint64
+	QuotaPeakNonPagedPoolUsage uint64
+	QuotaNonPagedPoolUsage     uint64
+	PagefileUsage              uint64
+	PeakPagefileUsage          uint64
+}