编写基于清单的事件
必须先注册提供程序,然后才能将事件写入跟踪会话。 注册提供程序会告知 ETW 提供程序已准备好将事件写入跟踪会话。 一个进程最多可以注册 1,024 个提供程序 GUID;但是,应将进程注册的提供程序数限制为一个或两个。
在 Windows Vista 之前: 进程可以注册的提供程序数没有限制。
若要注册基于清单的提供程序,请调用 EventRegister 函数。 函数注册提供程序的 GUID,并标识 ETW 在控制器启用或禁用提供程序时调用的可选回调。
在提供程序退出之前,调用 EventUnregister 函数以从 ETW 中删除提供程序的注册。 EventRegister 函数返回传递给 EventUnregister 函数的注册句柄。
当会话启用或禁用提供程序时,基于清单的提供程序不必实现 EnableCallback 函数即可接收通知。 回调是可选的,用于提供信息;注册提供程序时,无需指定或实现回调。 基于清单的提供程序只需编写事件,ETW 将决定是否将事件记录到跟踪会话。 如果事件需要执行大量工作来生成事件的数据,则可能需要先调用 EventEnabled 或 EventProviderEnabled 函数,以验证在执行工作之前,事件是否将写入会话。
通常,如果提供程序要求控制器传递提供程序定义的筛选器数据 (看到 EnableCallback 的 FilterData 参数) 提供程序,或者提供程序使用它在注册自己时指定的上下文信息 (看到 EventRegister) 的 CallbackContext 参数,则实现回调。
基于清单 的提供程序调用 EventWrite 或 EventWriteString 函数将事件写入会话。 如果事件数据是字符串,或者如果未为提供程序定义清单,并且事件数据是单个字符串,请调用 EventWriteString 函数来编写事件。 对于包含数值或复杂数据类型的事件数据,调用 EventWrite 函数来记录事件。
以下示例演示如何准备使用 EventWrite 函数写入的事件数据。 该示例引用为 基于清单的提供程序发布事件架构中定义的事件。
#include <windows.h>
#include <stdio.h>
#include <evntprov.h>
#include "provider.h" // Generated from manifest
#define SUNDAY 0X1
#define MONDAY 0X2
#define TUESDAY 0X4
#define WEDNESDAY 0X8
#define THURSDAY 0X10
#define FRIDAY 0X20
#define SATURDAY 0X40
enum TRANSFER_TYPE {
Download = 1,
Upload,
UploadReply
};
#define MAX_NAMEDVALUES 5 // Maximum array size
#define MAX_PAYLOAD_DESCRIPTORS 9 + (2 * MAX_NAMEDVALUES)
typedef struct _namedvalue {
LPWSTR name;
USHORT value;
} NAMEDVALUE, *PNAMEDVALUE;
void wmain(void)
{
DWORD status = ERROR_SUCCESS;
REGHANDLE RegistrationHandle = NULL;
EVENT_DATA_DESCRIPTOR Descriptors[MAX_PAYLOAD_DESCRIPTORS];
DWORD i = 0;
// Data to load into event descriptors
USHORT Scores[3] = {45, 63, 21};
ULONG pImage = (ULONG)&Scores;
DWORD TransferType = Upload;
DWORD Day = MONDAY | TUESDAY;
LPWSTR Path = L"c:\\path\\folder\\file.ext";
BYTE Cert[11] = {0x2, 0x4, 0x8, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x0, 0x1};
PBYTE Guid = (PBYTE) &ProviderGuid;
USHORT ArraySize = MAX_NAMEDVALUES;
BOOL IsLocal = TRUE;
NAMEDVALUE NamedValues[MAX_NAMEDVALUES] = {
{L"Bill", 1},
{L"Bob", 2},
{L"William", 3},
{L"Robert", 4},
{L"", 5}
};
status = EventRegister(
&ProviderGuid, // GUID that identifies the provider
NULL, // Callback not used
NULL, // Context noot used
&RegistrationHandle // Used when calling EventWrite and EventUnregister
);
if (ERROR_SUCCESS != status)
{
wprintf(L"EventRegister failed with %lu\n", status);
goto cleanup;
}
// Load the array of data descriptors for the TransferEvent event.
// Add the data to the array in the order of the <data> elements
// defined in the event's template.
EventDataDescCreate(&Descriptors[i++], &pImage, sizeof(ULONG));
EventDataDescCreate(&Descriptors[i++], Scores, sizeof(Scores));
EventDataDescCreate(&Descriptors[i++], Guid, sizeof(GUID));
EventDataDescCreate(&Descriptors[i++], Cert, sizeof(Cert));
EventDataDescCreate(&Descriptors[i++], &IsLocal, sizeof(BOOL));
EventDataDescCreate(&Descriptors[i++], Path, (ULONG)(wcslen(Path) + 1) * sizeof(WCHAR));
EventDataDescCreate(&Descriptors[i++], &ArraySize, sizeof(USHORT));
// If your event contains a structure, you should write each member
// of the structure separately. If the structure contained integral data types
// such as DWORDs and the data types were aligned on an 8-byte boundary, you
// could use the following call to write the structure, however, you are
// encouraged to write the members separately.
//
// EventDataDescCreate(&EvtData, struct, sizeof(struct));
//
// Because the array of structures in this example contains both strings
// and numbers, you must write each member of the structure separately.
for (int j = 0; j < MAX_NAMEDVALUES; j++)
{
EventDataDescCreate(&Descriptors[i++], NamedValues[j].name, (ULONG)(wcslen(NamedValues[j].name)+1) * sizeof(WCHAR) );
EventDataDescCreate(&Descriptors[i++], &(NamedValues[j].value), sizeof(USHORT) );
}
EventDataDescCreate(&Descriptors[i++], &Day, sizeof(DWORD));
EventDataDescCreate(&Descriptors[i++], &TransferType, sizeof(DWORD));
// Write the event. You do not have to verify if your provider is enabled before
// writing the event. ETW will write the event to any session that enabled
// the provider. If no session enabled the provider, the event is not
// written. If you need to perform extra work to write an event that you
// would not otherwise do, you may want to call the EventEnabled function
// before performing the extra work. The EventEnabled function tells you if a
// session has enabled your provider, so you know if you need to perform the
// extra work or not.
status = EventWrite(
RegistrationHandle, // From EventRegister
&TransferEvent, // EVENT_DESCRIPTOR generated from the manifest
(ULONG)MAX_PAYLOAD_DESCRIPTORS, // Size of the array of EVENT_DATA_DESCRIPTORs
&Descriptors[0] // Array of descriptors that contain the event data
);
if (status != ERROR_SUCCESS)
{
wprintf(L"EventWrite failed with 0x%x", status);
}
cleanup:
EventUnregister(RegistrationHandle);
}
编译清单 (参阅编译上述示例使用的 检测清单) 时,它会创建上) 示例中引用的以下头文件 (。
//**********************************************************************`
//* This is an include file generated by Message Compiler. *`
//* *`
//* Copyright (c) Microsoft Corporation. All Rights Reserved. *`
//**********************************************************************`
#pragma once
//+
// Provider Microsoft-Windows-ETWProvider Event Count 1
//+
EXTERN_C __declspec(selectany) const GUID ProviderGuid = {0xd8909c24, 0x5be9, 0x4502, {0x98, 0xca, 0xab, 0x7b, 0xdc, 0x24, 0x89, 0x9d}};
//
// Keyword
//
#define READ_KEYWORD 0x1
#define WRITE_KEYWORD 0x2
#define LOCAL_KEYWORD 0x4
#define REMOTE_KEYWORD 0x8
//
// Event Descriptors
//
EXTERN_C __declspec(selectany) const EVENT_DESCRIPTOR TransferEvent = {0x1, 0x0, 0x0, 0x4, 0x0, 0x0, 0x5};
#define TransferEvent_value 0x1
#define MSG_Provider_Name 0x90000001L
#define MSG_Event_WhenToTransfer 0xB0000001L
#define MSG_Map_Download 0xD0000001L
#define MSG_Map_Upload 0xD0000002L
#define MSG_Map_UploadReply 0xD0000003L
#define MSG_Map_Sunday 0xF0000001L
#define MSG_Map_Monday 0xF0000002L
#define MSG_Map_Tuesday 0xF0000003L
#define MSG_Map_Wednesday 0xF0000004L
#define MSG_Map_Thursday 0xF0000005L
#define MSG_Map_Friday 0xF0000006L
#define MSG_Map_Saturday 0xF0000007L