private void DoAddCounters(IEnumerable <IPerfCounter> counters)
{
uint result;
if (_query == null)
{
PdhQueryHandle query;
result = Pdh.PdhOpenQueryW(null, IntPtr.Zero, out query);
if (result != 0)
{
throw new Win32Exception((int)result);
}
_query = query;
}
List <IPerfCounter> missingCounters = new List <IPerfCounter>();
foreach (var counter in counters)
{
PdhCounterHandle hCounter;
result = Pdh.PdhAddEnglishCounterW(_query, counter.Path, IntPtr.Zero, out hCounter);
if (result == Pdh.PDH_CSTATUS_NO_OBJECT ||
result == Pdh.PDH_CSTATUS_NO_COUNTER)
{
missingCounters.Add(counter);
continue;
}
if (result != 0)
{
throw new Win32Exception((int)result);
}
_counters[counter] = hCounter;
}
if (missingCounters.Count > 0)
{
throw new MissingCountersException(missingCounters);
}
}
private string LookupName(uint index)
{
uint bufSize = 0;
uint result = Pdh.PdhLookupPerfNameByIndexW(null, index, null, ref bufSize);
if (result != 0 && result != Pdh.PDH_MORE_DATA)
{
throw new Win32Exception((int)result);
}
StringBuilder buffer = new StringBuilder((int)bufSize);
result = Pdh.PdhLookupPerfNameByIndexW(null, index, buffer, ref bufSize);
if (result != 0)
{
throw new Win32Exception((int)result);
}
return(buffer.ToString());
}
protected override bool ReleaseHandle()
{
return(Pdh.PdhRemoveCounter(handle) == 0);
}
protected override bool ReleaseHandle()
{
return(Pdh.PdhCloseQuery(handle) == 0);
}
protected override bool ReleaseHandle()
{
return(Pdh.PdhCloseLog(handle, Pdh.PDH_FLAGS_CLOSE_QUERY) == 0);
}
private List <string> ExpandCounterPath(string searchPattern, PdhExpansionFlags flags)
{
long cchPathListLength = 0;
uint result = 0;
byte[] buffer = null;
//
// Do - while, the buffer can grow after being told the necessary size
do
{
IntPtr mszExpandedPathList = IntPtr.Zero;
if (cchPathListLength > 0)
{
//
// If we received a buffer size allocate one
// Unicode size is 2 bytes
mszExpandedPathList = Marshal.AllocHGlobal(2 * (int)cchPathListLength);
}
try {
result = Pdh.PdhExpandWildCardPathW(null, searchPattern, mszExpandedPathList, ref cchPathListLength, flags);
if (result == Pdh.PDH_MORE_DATA)
{
continue;
}
if (result == Pdh.PDH_CSTATUS_NO_OBJECT || result == Pdh.PDH_CSTATUS_NO_INSTANCE)
{
return(new List <string>());
}
if (result != 0 && result != Pdh.PDH_MORE_DATA)
{
throw new Win32Exception((int)result);
}
buffer = new byte[cchPathListLength * 2];
Marshal.Copy(mszExpandedPathList, buffer, 0, buffer.Length);
}
finally {
//
// Always clean up allocated buffer
if (mszExpandedPathList != IntPtr.Zero)
{
Marshal.FreeHGlobal(mszExpandedPathList);
}
}
} while (result == Pdh.PDH_MORE_DATA);
if (buffer == null)
{
throw new Win32Exception((int)result);
}
//
// Parse paths from filled buffer
List <string> strings = new List <string>();
int start = 0;
int end = 0;
var chars = Encoding.Unicode.GetChars(buffer);
do
{
do
{
end++;
}while (end < chars.Length && chars[end] != 0);
strings.Add(new string(chars, start, end - start));
start = end;
} while (start < chars.Length - 1 && chars[start + 1] != 0);
return(strings);
}
public async Task DoRefresh()
{
if (!NeedsRefresh)
{
return;
}
PDH_FMT_COUNTERVALUE value = default(PDH_FMT_COUNTERVALUE);
uint result = Pdh.PdhCollectQueryData(_query);
if (result == Pdh.PDH_NO_DATA)
{
throw new MissingCountersException(_counters.Keys);
}
if (result != 0)
{
throw new Win32Exception((int)result);
}
bool multiSample = false;
List <IPerfCounter> missingCounters = new List <IPerfCounter>();
foreach (KeyValuePair <IPerfCounter, PdhCounterHandle> counterInstance in _counters)
{
IPerfCounter counter = counterInstance.Key;
PdhCounterHandle handle = counterInstance.Value;
result = Pdh.PdhGetFormattedCounterValue(handle, PdhFormat.PDH_FMT_LARGE, IntPtr.Zero, out value);
if (result == Pdh.PDH_INVALID_DATA && value.CStatus == Pdh.PDH_CSTATUS_INVALID_DATA && !multiSample)
{
multiSample = true;
result = Pdh.PdhCollectQueryData(_query);
if (result != 0)
{
throw new Win32Exception((int)result);
}
result = Pdh.PdhGetFormattedCounterValue(handle, PdhFormat.PDH_FMT_LARGE, IntPtr.Zero, out value);
}
if ((result != 0 && value.CStatus == Pdh.PDH_CSTATUS_NO_INSTANCE) ||
result == Pdh.PDH_INVALID_HANDLE ||
result == Pdh.PDH_CALC_NEGATIVE_VALUE ||
result == Pdh.PDH_CALC_NEGATIVE_DENOMINATOR ||
(result == Pdh.PDH_INVALID_DATA && value.CStatus == Pdh.PDH_INVALID_DATA))
{
missingCounters.Add(counter);
continue;
}
else if (result != 0)
{
if (!_counterFinder.CounterExists(counter))
{
missingCounters.Add(counter);
continue;
}
throw new Win32Exception((int)result);
}
else if (value.CStatus != 0)
{
throw new Win32Exception((int)value.CStatus);
}
counter.Value = value.longLongValue;
}
if (missingCounters.Count > 0)
{
throw new MissingCountersException(missingCounters);
}
TimeSpan calculationDelta = DateTime.UtcNow - _lastCalculatedTime;
_lastCalculatedTime = DateTime.UtcNow;
}