通过进程名获取进程id

BOOL GetProcessInfo(wchar_t *szProcessName,ULONG * ProcessId)
{
NTSTATUS	status;
ULONG		RetLen;

BOOL		bIsSuccess = FALSE;

PVOID			ProcessInfo;
SYSTEM_PROCESS_INFORMATION*	p;

if (ProcessId == NULL || szProcessName == NULL)
{
return FALSE;
}

status = ZwQuerySystemInformation(SystemProcessInformation,0,0,&RetLen);
if (status != STATUS_INFO_LENGTH_MISMATCH)
{
return bIsSuccess;
}

ProcessInfo = malloc(RetLen);
if (ProcessInfo == NULL)
{
return bIsSuccess;
}

status = ZwQuerySystemInformation(SystemProcessInformation,ProcessInfo,RetLen,&RetLen);
if (!NT_SUCCESS(status))
{
free(ProcessInfo);
return bIsSuccess;
}

p = (SYSTEM_PROCESS_INFORMATION*)ProcessInfo;
while(p->NextEntryOffset)
{
if (szProcessName != NULL &&
p->ImageName.Length >= wcslen(szProcessName) &&
wcscmp(p->ImageName.Buffer,szProcessName) == 0)
{
bIsSuccess = TRUE;
*ProcessId = (ULONG)p->ProcessId;
break;
}

p = (SYSTEM_PROCESS_INFORMATION*)((ULONG)p + p->NextEntryOffset);
}

free(ProcessInfo);

return bIsSuccess;
}