win7上获得每个进程的CPU使用率，求C/C++代码

win7下获得每个进程的CPU使用率，求C/C++代码
win7下获得每个进程的CPU使用率，求C/C++代码。
------解决方案--------------------

function GetCPUUsage(var liOldIdleTime, liOldSystemTime: LARGE_INTEGER): string;

type

  TSystem_Basic_Information = packed record

    dwUnknown1: DWORD;

    uKeMaximumIncrement: ULONG;

    uPageSize: ULONG;

    uMmNumberOfPhysicalPages: ULONG;

    uMmLowestPhysicalPage: ULONG;

    uMmHighestPhysicalPage: ULONG;

    uAllocationGranularity: ULONG;

    pLowestUserAddress: Pointer;

    pMmHighestUserAddress: Pointer;

    uKeActiveProcessors: ULONG;

    bKeNumberProcessors: byte;

    bUnknown2: byte;

    wUnknown3: word;

  end;


  TSystem_Performance_Information = packed record

    liIdleTime: LARGE_INTEGER; {LARGE_INTEGER}

    dwSpare: array[0..75] of DWORD;

  end;


  TSystem_Time_Information = packed record

    liKeBootTime: LARGE_INTEGER;

    liKeSystemTime: LARGE_INTEGER;

    liExpTimeZoneBias: LARGE_INTEGER;

    uCurrentTimeZoneId: ULONG;

    dwReserved: DWORD;

  end;


  TNtQuerySystemInformation = function(infoClass: DWORD; buffer: Pointer; bufSize: DWORD; var returnSize: Dword): DWORD; stdcall;

var

  NtQuerySystemInformation: TNtQuerySystemInformation;

  SysBaseInfo: TSystem_Basic_Information;

  SysPerfInfo: TSystem_Performance_Information;

  SysTimeInfo: TSystem_Time_Information;

  status: DWORD; {long}

  dbSystemTime: Double;

  dbIdleTime: Double;

begin

  Result := '<N/A>';


  NtQuerySystemInformation := GetProcAddress(GetModuleHandle('ntdll.dll'), 'NtQuerySystemInformation');

  if @NtQuerySystemInformation = nil then Exit;

  

  if (NtQuerySystemInformation(0, @SysBaseInfo, SizeOf(SysBaseInfo), status) <> 0)

    or (NtQuerySystemInformation(3, @SysTimeInfo, SizeOf(SysTimeInfo), status) <> 0)

    or (NtQuerySystemInformation(2, @SysPerfInfo, SizeOf(SysPerfInfo), status) <> 0) then Exit;


  if liOldIdleTime.QuadPart <> 0 then

  begin

    // CurrentValue = NewValue - OldValue

    dbIdleTime := Li2Double(SysPerfInfo.liIdleTime) - Li2Double(liOldIdleTime);

    dbSystemTime := Li2Double(SysTimeInfo.liKeSystemTime) - Li2Double(liOldSystemTime);


    // CurrentCpuIdle = IdleTime / SystemTime

    dbIdleTime := dbIdleTime / dbSystemTime;


    // CurrentCpuUsage% = 100 - (CurrentCpuIdle * 100) / NumberOfProcessors