container: support hostprocess containers and expose kubernetes labels (#1911)

internal/headers/hcn/syscall.go

@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: Apache-2.0
+//
+// Copyright The Prometheus Authors
+// 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.
+
+//go:build windows
+
+package hcn
+
+import (
+	"encoding/json"
+	"fmt"
+	"unsafe"
+
+	"github.com/prometheus-community/windows_exporter/internal/headers/guid"
+	"github.com/prometheus-community/windows_exporter/internal/headers/hcs"
+	"golang.org/x/sys/windows"
+)
+
+//nolint:gochecknoglobals
+var (
+	modComputeNetwork = windows.NewLazySystemDLL("computenetwork.dll")
+
+	procHcnEnumerateEndpoints      = modComputeNetwork.NewProc("HcnEnumerateEndpoints")
+	procHcnOpenEndpoint            = modComputeNetwork.NewProc("HcnOpenEndpoint")
+	procHcnQueryEndpointProperties = modComputeNetwork.NewProc("HcnQueryEndpointProperties")
+	procHcnCloseEndpoint           = modComputeNetwork.NewProc("HcnCloseEndpoint")
+)
+
+// EnumerateEndpoints enumerates the endpoints.
+//
+// https://learn.microsoft.com/en-us/virtualization/api/hcn/reference/hcnenumerateendpoints
+func EnumerateEndpoints() ([]guid.GUID, error) {
+	var (
+		endpointsJSON *uint16
+		errorRecord   *uint16
+	)
+
+	r1, _, _ := procHcnEnumerateEndpoints.Call(
+		0,
+		uintptr(unsafe.Pointer(&endpointsJSON)),
+		uintptr(unsafe.Pointer(&errorRecord)),
+	)
+
+	windows.CoTaskMemFree(unsafe.Pointer(errorRecord))
+	result := windows.UTF16PtrToString(endpointsJSON)
+
+	if r1 != 0 {
+		return nil, fmt.Errorf("HcnEnumerateEndpoints failed: HRESULT 0x%X: %w", r1, hcs.Win32FromHResult(r1))
+	}
+
+	var endpoints []guid.GUID
+
+	if err := json.Unmarshal([]byte(result), &endpoints); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal JSON: %w", err)
+	}
+
+	return endpoints, nil
+}
+
+// OpenEndpoint opens an endpoint.
+//
+// https://learn.microsoft.com/en-us/virtualization/api/hcn/reference/hcnopenendpoint
+func OpenEndpoint(id guid.GUID) (Endpoint, error) {
+	var (
+		endpoint    Endpoint
+		errorRecord *uint16
+	)
+
+	r1, _, _ := procHcnOpenEndpoint.Call(
+		uintptr(unsafe.Pointer(&id)),
+		uintptr(unsafe.Pointer(&endpoint)),
+		uintptr(unsafe.Pointer(&errorRecord)),
+	)
+
+	windows.CoTaskMemFree(unsafe.Pointer(errorRecord))
+
+	if r1 != 0 {
+		return 0, fmt.Errorf("HcnOpenEndpoint failed: HRESULT 0x%X: %w", r1, hcs.Win32FromHResult(r1))
+	}
+
+	return endpoint, nil
+}
+
+// QueryEndpointProperties queries the properties of an endpoint.
+//
+// https://learn.microsoft.com/en-us/virtualization/api/hcn/reference/hcnqueryendpointproperties
+func QueryEndpointProperties(endpoint Endpoint, propertyQuery *uint16) (EndpointProperties, error) {
+	var (
+		resultDocument *uint16
+		errorRecord    *uint16
+	)
+
+	r1, _, _ := procHcnQueryEndpointProperties.Call(
+		uintptr(endpoint),
+		uintptr(unsafe.Pointer(&propertyQuery)),
+		uintptr(unsafe.Pointer(&resultDocument)),
+		uintptr(unsafe.Pointer(&errorRecord)),
+	)
+
+	windows.CoTaskMemFree(unsafe.Pointer(errorRecord))
+
+	result := windows.UTF16PtrToString(resultDocument)
+	windows.CoTaskMemFree(unsafe.Pointer(resultDocument))
+
+	if r1 != 0 {
+		return EndpointProperties{}, fmt.Errorf("HcsGetComputeSystemProperties failed: HRESULT 0x%X: %w", r1, hcs.Win32FromHResult(r1))
+	}
+
+	var properties EndpointProperties
+
+	if err := json.Unmarshal([]byte(result), &properties); err != nil {
+		return EndpointProperties{}, fmt.Errorf("failed to unmarshal JSON: %w", err)
+	}
+
+	return properties, nil
+}
+
+// CloseEndpoint close a handle to an Endpoint.
+//
+// https://learn.microsoft.com/en-us/virtualization/api/hcn/reference/hcncloseendpoint
+func CloseEndpoint(endpoint Endpoint) {
+	_, _, _ = procHcnCloseEndpoint.Call(uintptr(endpoint))
+}