[PATCH v4 05/11] ntoskrnl.exe: Implement PsLookupProcessByProcessId.

[Derek Lesho]

Signed-off-by: Derek Lesho 
---
 dlls/ntoskrnl.exe/ntoskrnl.c | 15 ++++++++++++---
 include/ddk/ntifs.h          |  1 +
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/dlls/ntoskrnl.exe/ntoskrnl.c b/dlls/ntoskrnl.exe/ntoskrnl.c
index 6edb7037a0..4685f3c394 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.c
+++ b/dlls/ntoskrnl.exe/ntoskrnl.c
@@ -3242,9 +3242,18 @@ NTSTATUS WINAPI PsSetLoadImageNotifyRoutine(PLOAD_IMAGE_NOTIFY_ROUTINE routine)
  */
 NTSTATUS WINAPI PsLookupProcessByProcessId(HANDLE processid, PEPROCESS *process)
 {
-    static int once;
-    if (!once++) FIXME("(%p %p) stub\n", processid, process);
-    return STATUS_NOT_IMPLEMENTED;
+    NTSTATUS status;
+    HANDLE hProcess = OpenProcess( PROCESS_ALL_ACCESS, FALSE, HandleToUlong(processid) );
+
+    if (!hProcess)
+        return STATUS_INVALID_PARAMETER;
+
+    status = kernel_object_from_handle( hProcess, PsProcessType, (void**)process );
+
+    ObReferenceObject( *process );
+
+    NtClose( hProcess );
+    return status;
 }

diff --git a/include/ddk/ntifs.h b/include/ddk/ntifs.h
index 9b57ae7ad7..ec4d1d5aa7 100644
--- a/include/ddk/ntifs.h
+++ b/include/ddk/ntifs.h
@@ -131,6 +131,7 @@ typedef struct _FS_FILTER_CALLBACKS

BOOLEAN WINAPI FsRtlIsNameInExpression(PUNICODE_STRING, PUNICODE_STRING, BOOLEAN, PWCH);
 NTSTATUS WINAPI ObQueryNameString(PVOID,POBJECT_NAME_INFORMATION,ULONG,PULONG);
+NTSTATUS WINAPI PsLookupProcessByProcessId(HANDLE,PEPROCESS*);
 NTSTATUS WINAPI PsLookupThreadByThreadId(HANDLE,PETHREAD*);
 void WINAPI PsRevertToSelf(void);