1 files changed, 499 insertions, 0 deletions
diff --git a/vendor/github.com/Microsoft/hcsshim/internal/jobobject/jobobject.go b/vendor/github.com/Microsoft/hcsshim/internal/jobobject/jobobject.go
new file mode 100644
index 000000000..9c2726416
--- /dev/null
+++ b/vendor/github.com/Microsoft/hcsshim/internal/jobobject/jobobject.go
@@ -0,0 +1,499 @@
+package jobobject
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sync"
+	"unsafe"
+
+	"github.com/Microsoft/hcsshim/internal/queue"
+	"github.com/Microsoft/hcsshim/internal/winapi"
+	"golang.org/x/sys/windows"
+)
+
+// This file provides higher level constructs for the win32 job object API.
+// Most of the core creation and management functions are already present in "golang.org/x/sys/windows"
+// (CreateJobObject, AssignProcessToJobObject, etc.) as well as most of the limit information
+// structs and associated limit flags. Whatever is not present from the job object API
+// in golang.org/x/sys/windows is located in /internal/winapi.
+//
+// https://docs.microsoft.com/en-us/windows/win32/procthread/job-objects
+
+// JobObject is a high level wrapper around a Windows job object. Holds a handle to
+// the job, a queue to receive iocp notifications about the lifecycle
+// of the job and a mutex for synchronized handle access.
+type JobObject struct {
+	handle     windows.Handle
+	mq         *queue.MessageQueue
+	handleLock sync.RWMutex
+}
+
+// JobLimits represents the resource constraints that can be applied to a job object.
+type JobLimits struct {
+	CPULimit           uint32
+	CPUWeight          uint32
+	MemoryLimitInBytes uint64
+	MaxIOPS            int64
+	MaxBandwidth       int64
+}
+
+type CPURateControlType uint32
+
+const (
+	WeightBased CPURateControlType = iota
+	RateBased
+)
+
+// Processor resource controls
+const (
+	cpuLimitMin  = 1
+	cpuLimitMax  = 10000
+	cpuWeightMin = 1
+	cpuWeightMax = 9
+)
+
+var (
+	ErrAlreadyClosed = errors.New("the handle has already been closed")
+	ErrNotRegistered = errors.New("job is not registered to receive notifications")
+)
+
+// Options represents the set of configurable options when making or opening a job object.
+type Options struct {
+	// `Name` specifies the name of the job object if a named job object is desired.
+	Name string
+	// `Notifications` specifies if the job will be registered to receive notifications.
+	// Defaults to false.
+	Notifications bool
+	// `UseNTVariant` specifies if we should use the `Nt` variant of Open/CreateJobObject.
+	// Defaults to false.
+	UseNTVariant bool
+}
+
+// Create creates a job object.
+//
+// If options.Name is an empty string, the job will not be assigned a name.
+//
+// If options.Notifications are not enabled `PollNotifications` will return immediately with error `errNotRegistered`.
+//
+// If `options` is nil, use default option values.
+//
+// Returns a JobObject structure and an error if there is one.
+func Create(ctx context.Context, options *Options) (_ *JobObject, err error) {
+	if options == nil {
+		options = &Options{}
+	}
+
+	var jobName *winapi.UnicodeString
+	if options.Name != "" {
+		jobName, err = winapi.NewUnicodeString(options.Name)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	var jobHandle windows.Handle
+	if options.UseNTVariant {
+		oa := winapi.ObjectAttributes{
+			Length:     unsafe.Sizeof(winapi.ObjectAttributes{}),
+			ObjectName: jobName,
+			Attributes: 0,
+		}
+		status := winapi.NtCreateJobObject(&jobHandle, winapi.JOB_OBJECT_ALL_ACCESS, &oa)
+		if status != 0 {
+			return nil, winapi.RtlNtStatusToDosError(status)
+		}
+	} else {
+		var jobNameBuf *uint16
+		if jobName != nil && jobName.Buffer != nil {
+			jobNameBuf = jobName.Buffer
+		}
+		jobHandle, err = windows.CreateJobObject(nil, jobNameBuf)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	defer func() {
+		if err != nil {
+			windows.Close(jobHandle)
+		}
+	}()
+
+	job := &JobObject{
+		handle: jobHandle,
+	}
+
+	// If the IOCP we'll be using to receive messages for all jobs hasn't been
+	// created, create it and start polling.
+	if options.Notifications {
+		mq, err := setupNotifications(ctx, job)
+		if err != nil {
+			return nil, err
+		}
+		job.mq = mq
+	}
+
+	return job, nil
+}
+
+// Open opens an existing job object with name provided in `options`. If no name is provided
+// return an error since we need to know what job object to open.
+//
+// If options.Notifications is false `PollNotifications` will return immediately with error `errNotRegistered`.
+//
+// Returns a JobObject structure and an error if there is one.
+func Open(ctx context.Context, options *Options) (_ *JobObject, err error) {
+	if options == nil || (options != nil && options.Name == "") {
+		return nil, errors.New("no job object name specified to open")
+	}
+
+	unicodeJobName, err := winapi.NewUnicodeString(options.Name)
+	if err != nil {
+		return nil, err
+	}
+
+	var jobHandle windows.Handle
+	if options != nil && options.UseNTVariant {
+		oa := winapi.ObjectAttributes{
+			Length:     unsafe.Sizeof(winapi.ObjectAttributes{}),
+			ObjectName: unicodeJobName,
+			Attributes: 0,
+		}
+		status := winapi.NtOpenJobObject(&jobHandle, winapi.JOB_OBJECT_ALL_ACCESS, &oa)
+		if status != 0 {
+			return nil, winapi.RtlNtStatusToDosError(status)
+		}
+	} else {
+		jobHandle, err = winapi.OpenJobObject(winapi.JOB_OBJECT_ALL_ACCESS, false, unicodeJobName.Buffer)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	defer func() {
+		if err != nil {
+			windows.Close(jobHandle)
+		}
+	}()
+
+	job := &JobObject{
+		handle: jobHandle,
+	}
+
+	// If the IOCP we'll be using to receive messages for all jobs hasn't been
+	// created, create it and start polling.
+	if options != nil && options.Notifications {
+		mq, err := setupNotifications(ctx, job)
+		if err != nil {
+			return nil, err
+		}
+		job.mq = mq
+	}
+
+	return job, nil
+}
+
+// helper function to setup notifications for creating/opening a job object
+func setupNotifications(ctx context.Context, job *JobObject) (*queue.MessageQueue, error) {
+	job.handleLock.RLock()
+	defer job.handleLock.RUnlock()
+
+	if job.handle == 0 {
+		return nil, ErrAlreadyClosed
+	}
+
+	ioInitOnce.Do(func() {
+		h, err := windows.CreateIoCompletionPort(windows.InvalidHandle, 0, 0, 0xffffffff)
+		if err != nil {
+			initIOErr = err
+			return
+		}
+		ioCompletionPort = h
+		go pollIOCP(ctx, h)
+	})
+
+	if initIOErr != nil {
+		return nil, initIOErr
+	}
+
+	mq := queue.NewMessageQueue()
+	jobMap.Store(uintptr(job.handle), mq)
+	if err := attachIOCP(job.handle, ioCompletionPort); err != nil {
+		jobMap.Delete(uintptr(job.handle))
+		return nil, fmt.Errorf("failed to attach job to IO completion port: %w", err)
+	}
+	return mq, nil
+}
+
+// PollNotification will poll for a job object notification. This call should only be called once
+// per job (ideally in a goroutine loop) and will block if there is not a notification ready.
+// This call will return immediately with error `ErrNotRegistered` if the job was not registered
+// to receive notifications during `Create`. Internally, messages will be queued and there
+// is no worry of messages being dropped.
+func (job *JobObject) PollNotification() (interface{}, error) {
+	if job.mq == nil {
+		return nil, ErrNotRegistered
+	}
+	return job.mq.ReadOrWait()
+}
+
+// UpdateProcThreadAttribute updates the passed in ProcThreadAttributeList to contain what is necessary to
+// launch a process in a job at creation time. This can be used to avoid having to call Assign() after a process
+// has already started running.
+func (job *JobObject) UpdateProcThreadAttribute(attrList *windows.ProcThreadAttributeListContainer) error {
+	job.handleLock.RLock()
+	defer job.handleLock.RUnlock()
+
+	if job.handle == 0 {
+		return ErrAlreadyClosed
+	}
+
+	if err := attrList.Update(
+		winapi.PROC_THREAD_ATTRIBUTE_JOB_LIST,
+		unsafe.Pointer(&job.handle),
+		unsafe.Sizeof(job.handle),
+	); err != nil {
+		return fmt.Errorf("failed to update proc thread attributes for job object: %w", err)
+	}
+
+	return nil
+}
+
+// Close closes the job object handle.
+func (job *JobObject) Close() error {
+	job.handleLock.Lock()
+	defer job.handleLock.Unlock()
+
+	if job.handle == 0 {
+		return ErrAlreadyClosed
+	}
+
+	if err := windows.Close(job.handle); err != nil {
+		return err
+	}
+
+	if job.mq != nil {
+		job.mq.Close()
+	}
+	// Handles now invalid so if the map entry to receive notifications for this job still
+	// exists remove it so we can stop receiving notifications.
+	if _, ok := jobMap.Load(uintptr(job.handle)); ok {
+		jobMap.Delete(uintptr(job.handle))
+	}
+
+	job.handle = 0
+	return nil
+}
+
+// Assign assigns a process to the job object.
+func (job *JobObject) Assign(pid uint32) error {
+	job.handleLock.RLock()
+	defer job.handleLock.RUnlock()
+
+	if job.handle == 0 {
+		return ErrAlreadyClosed
+	}
+
+	if pid == 0 {
+		return errors.New("invalid pid: 0")
+	}
+	hProc, err := windows.OpenProcess(winapi.PROCESS_ALL_ACCESS, true, pid)
+	if err != nil {
+		return err
+	}
+	defer windows.Close(hProc)
+	return windows.AssignProcessToJobObject(job.handle, hProc)
+}
+
+// Terminate terminates the job, essentially calls TerminateProcess on every process in the
+// job.
+func (job *JobObject) Terminate(exitCode uint32) error {
+	job.handleLock.RLock()
+	defer job.handleLock.RUnlock()
+	if job.handle == 0 {
+		return ErrAlreadyClosed
+	}
+	return windows.TerminateJobObject(job.handle, exitCode)
+}
+
+// Pids returns all of the process IDs in the job object.
+func (job *JobObject) Pids() ([]uint32, error) {
+	job.handleLock.RLock()
+	defer job.handleLock.RUnlock()
+
+	if job.handle == 0 {
+		return nil, ErrAlreadyClosed
+	}
+
+	info := winapi.JOBOBJECT_BASIC_PROCESS_ID_LIST{}
+	err := winapi.QueryInformationJobObject(
+		job.handle,
+		winapi.JobObjectBasicProcessIdList,
+		uintptr(unsafe.Pointer(&info)),
+		uint32(unsafe.Sizeof(info)),
+		nil,
+	)
+
+	// This is either the case where there is only one process or no processes in
+	// the job. Any other case will result in ERROR_MORE_DATA. Check if info.NumberOfProcessIdsInList
+	// is 1 and just return this, otherwise return an empty slice.
+	if err == nil {
+		if info.NumberOfProcessIdsInList == 1 {
+			return []uint32{uint32(info.ProcessIdList[0])}, nil
+		}
+		// Return empty slice instead of nil to play well with the caller of this.
+		// Do not return an error if no processes are running inside the job
+		return []uint32{}, nil
+	}
+
+	if err != winapi.ERROR_MORE_DATA {
+		return nil, fmt.Errorf("failed initial query for PIDs in job object: %w", err)
+	}
+
+	jobBasicProcessIDListSize := unsafe.Sizeof(info) + (unsafe.Sizeof(info.ProcessIdList[0]) * uintptr(info.NumberOfAssignedProcesses-1))
+	buf := make([]byte, jobBasicProcessIDListSize)
+	if err = winapi.QueryInformationJobObject(
+		job.handle,
+		winapi.JobObjectBasicProcessIdList,
+		uintptr(unsafe.Pointer(&buf[0])),
+		uint32(len(buf)),
+		nil,
+	); err != nil {
+		return nil, fmt.Errorf("failed to query for PIDs in job object: %w", err)
+	}
+
+	bufInfo := (*winapi.JOBOBJECT_BASIC_PROCESS_ID_LIST)(unsafe.Pointer(&buf[0]))
+	pids := make([]uint32, bufInfo.NumberOfProcessIdsInList)
+	for i, bufPid := range bufInfo.AllPids() {
+		pids[i] = uint32(bufPid)
+	}
+	return pids, nil
+}
+
+// QueryMemoryStats gets the memory stats for the job object.
+func (job *JobObject) QueryMemoryStats() (*winapi.JOBOBJECT_MEMORY_USAGE_INFORMATION, error) {
+	job.handleLock.RLock()
+	defer job.handleLock.RUnlock()
+
+	if job.handle == 0 {
+		return nil, ErrAlreadyClosed
+	}
+
+	info := winapi.JOBOBJECT_MEMORY_USAGE_INFORMATION{}
+	if err := winapi.QueryInformationJobObject(
+		job.handle,
+		winapi.JobObjectMemoryUsageInformation,
+		uintptr(unsafe.Pointer(&info)),
+		uint32(unsafe.Sizeof(info)),
+		nil,
+	); err != nil {
+		return nil, fmt.Errorf("failed to query for job object memory stats: %w", err)
+	}
+	return &info, nil
+}
+
+// QueryProcessorStats gets the processor stats for the job object.
+func (job *JobObject) QueryProcessorStats() (*winapi.JOBOBJECT_BASIC_ACCOUNTING_INFORMATION, error) {
+	job.handleLock.RLock()
+	defer job.handleLock.RUnlock()
+
+	if job.handle == 0 {
+		return nil, ErrAlreadyClosed
+	}
+
+	info := winapi.JOBOBJECT_BASIC_ACCOUNTING_INFORMATION{}
+	if err := winapi.QueryInformationJobObject(
+		job.handle,
+		winapi.JobObjectBasicAccountingInformation,
+		uintptr(unsafe.Pointer(&info)),
+		uint32(unsafe.Sizeof(info)),
+		nil,
+	); err != nil {
+		return nil, fmt.Errorf("failed to query for job object process stats: %w", err)
+	}
+	return &info, nil
+}
+
+// QueryStorageStats gets the storage (I/O) stats for the job object.
+func (job *JobObject) QueryStorageStats() (*winapi.JOBOBJECT_IO_ATTRIBUTION_INFORMATION, error) {
+	job.handleLock.RLock()
+	defer job.handleLock.RUnlock()
+
+	if job.handle == 0 {
+		return nil, ErrAlreadyClosed
+	}
+
+	info := winapi.JOBOBJECT_IO_ATTRIBUTION_INFORMATION{
+		ControlFlags: winapi.JOBOBJECT_IO_ATTRIBUTION_CONTROL_ENABLE,
+	}
+	if err := winapi.QueryInformationJobObject(
+		job.handle,
+		winapi.JobObjectIoAttribution,
+		uintptr(unsafe.Pointer(&info)),
+		uint32(unsafe.Sizeof(info)),
+		nil,
+	); err != nil {
+		return nil, fmt.Errorf("failed to query for job object storage stats: %w", err)
+	}
+	return &info, nil
+}
+
+// QueryPrivateWorkingSet returns the private working set size for the job. This is calculated by adding up the
+// private working set for every process running in the job.
+func (job *JobObject) QueryPrivateWorkingSet() (uint64, error) {
+	pids, err := job.Pids()
+	if err != nil {
+		return 0, err
+	}
+
+	openAndQueryWorkingSet := func(pid uint32) (uint64, error) {
+		h, err := windows.OpenProcess(windows.PROCESS_QUERY_LIMITED_INFORMATION, false, pid)
+		if err != nil {
+			// Continue to the next if OpenProcess doesn't return a valid handle (fails). Handles a
+			// case where one of the pids in the job exited before we open.
+			return 0, nil
+		}
+		defer func() {
+			_ = windows.Close(h)
+		}()
+		// Check if the process is actually running in the job still. There's a small chance
+		// that the process could have exited and had its pid re-used between grabbing the pids
+		// in the job and opening the handle to it above.
+		var inJob int32
+		if err := winapi.IsProcessInJob(h, job.handle, &inJob); err != nil {
+			// This shouldn't fail unless we have incorrect access rights which we control
+			// here so probably best to error out if this failed.
+			return 0, err
+		}
+		// Don't report stats for this process as it's not running in the job. This shouldn't be
+		// an error condition though.
+		if inJob == 0 {
+			return 0, nil
+		}
+
+		var vmCounters winapi.VM_COUNTERS_EX2
+		status := winapi.NtQueryInformationProcess(
+			h,
+			winapi.ProcessVmCounters,
+			uintptr(unsafe.Pointer(&vmCounters)),
+			uint32(unsafe.Sizeof(vmCounters)),
+			nil,
+		)
+		if !winapi.NTSuccess(status) {
+			return 0, fmt.Errorf("failed to query information for process: %w", winapi.RtlNtStatusToDosError(status))
+		}
+		return uint64(vmCounters.PrivateWorkingSetSize), nil
+	}
+
+	var jobWorkingSetSize uint64
+	for _, pid := range pids {
+		workingSet, err := openAndQueryWorkingSet(pid)
+		if err != nil {
+			return 0, err
+		}
+		jobWorkingSetSize += workingSet
+	}
+
+	return jobWorkingSetSize, nil
+}