sys: add trace functionality

2025-07-03 09:22:57 -05:00 · 2021-01-13 16:15:06 -08:00
parent 870c54253a
commit a5726c820b
6 changed files with 189 additions and 0 deletions
--- a/src/sys/trace.c
+++ b/src/sys/trace.c
@ -0,0 +1,142 @@
+/**
+ * @file sys/trace.c
+ *
+ * @copyright 2015-2020 Bill Zissimopoulos
+ */
+/*
+ * This file is part of WinFsp.
+ *
+ * You can redistribute it and/or modify it under the terms of the GNU
+ * General Public License version 3 as published by the Free Software
+ * Foundation.
+ *
+ * Licensees holding a valid commercial license may use this software
+ * in accordance with the commercial license agreement provided in
+ * conjunction with the software.  The terms and conditions of any such
+ * commercial license agreement shall govern, supersede, and render
+ * ineffective any application of the GPLv3 license to this software,
+ * notwithstanding of any reference thereto in the software or
+ * associated repository.
+ */
+
+#include <sys/driver.h>
+
+#if FSP_TRACE_ENABLED
+
+#undef STATUS_INSUFFICIENT_RESOURCES
+#define STATUS_INSUFFICIENT_RESOURCES   ((NTSTATUS)0xC000009AL)
+
+static struct
+{
+    HANDLE Handle;
+    PKEVENT Event;
+} FspLowMemoryCondition, FspLowNonPagedPoolCondition, FspLowPagedPoolCondition;
+
+VOID FspTrace(const char *file, int line, const char *func)
+{
+    for (const char *p = file; '\0' != *p; p++)
+        if ('\\' == *p)
+            file = p + 1;
+
+    ASSERT(DISPATCH_LEVEL >= KeGetCurrentIrql());
+    DbgPrintEx(DPFLTR_DEFAULT_ID, DPFLTR_TRACE_LEVEL,
+        DRIVER_NAME ": %s[%s:%d]\n", func, file, line);
+}
+
+VOID FspTraceNtStatus(const char *file, int line, const char *func, NTSTATUS Status)
+{
+    for (const char *p = file; '\0' != *p; p++)
+        if ('\\' == *p)
+            file = p + 1;
+
+    ASSERT(DISPATCH_LEVEL >= KeGetCurrentIrql());
+    BOOLEAN LowMemoryCondition, LowNonPagedPoolCondition, LowPagedPoolCondition;
+    switch (Status)
+    {
+    case STATUS_INSUFFICIENT_RESOURCES:
+        LowMemoryCondition = 0 != FspLowMemoryCondition.Event &&
+            !!KeReadStateEvent(FspLowMemoryCondition.Event);
+        LowNonPagedPoolCondition = 0 != FspLowNonPagedPoolCondition.Event &&
+            !!KeReadStateEvent(FspLowNonPagedPoolCondition.Event);
+        LowPagedPoolCondition = 0 != FspLowPagedPoolCondition.Event &&
+            !!KeReadStateEvent(FspLowPagedPoolCondition.Event);
+        DbgPrintEx(DPFLTR_DEFAULT_ID, DPFLTR_TRACE_LEVEL,
+            DRIVER_NAME ": %s[%s:%d]: STATUS_INSUFFICIENT_RESOURCE (Memory=%c%c%c)\n",
+            func, file, line,
+            LowMemoryCondition ? 'M' : '-',
+            LowNonPagedPoolCondition ? 'N' : '-',
+            LowPagedPoolCondition ? 'P' : '-');
+        break;
+    default:
+        DbgPrintEx(DPFLTR_DEFAULT_ID, DPFLTR_TRACE_LEVEL,
+            DRIVER_NAME ": %s[%s:%d]: Status=%lx\n",
+            func, file, line,
+            Status);
+        break;
+    }
+}
+
+static PKEVENT FspOpenEvent(PWSTR Name, PHANDLE PHandle)
+{
+    UNICODE_STRING ObjectName;
+    OBJECT_ATTRIBUTES ObjectAttributes;
+    HANDLE Handle;
+    PKEVENT Event;
+    NTSTATUS Result;
+
+    *PHandle = 0;
+
+    RtlInitUnicodeString(&ObjectName, Name);
+    InitializeObjectAttributes(&ObjectAttributes,
+        &ObjectName, OBJ_KERNEL_HANDLE, 0, 0);
+    Result = ZwOpenEvent(&Handle,
+        EVENT_ALL_ACCESS, &ObjectAttributes);
+    if (!NT_SUCCESS(Result))
+        return 0;
+
+    Result = ObReferenceObjectByHandle(Handle,
+        0, *ExEventObjectType, KernelMode, &Event, 0);
+    if (!NT_SUCCESS(Result))
+    {
+        ZwClose(Handle);
+        return 0;
+    }
+
+    *PHandle = Handle;
+
+    return Event;
+}
+
+static VOID FspCloseEvent(PKEVENT Event, HANDLE Handle)
+{
+    if (0 != Event)
+        ObDereferenceObject(Event);
+
+    if (0 != Handle)
+        ZwClose(Handle);
+}
+
+VOID FspTraceInitialize(VOID)
+{
+#define OPEN_EVENT(NAME)                \
+    (Fsp ## NAME.Event = FspOpenEvent(L"\\KernelObjects\\" #NAME, &Fsp ## NAME.Handle))
+
+    OPEN_EVENT(LowMemoryCondition);
+    OPEN_EVENT(LowNonPagedPoolCondition);
+    OPEN_EVENT(LowPagedPoolCondition);
+
+#undef OPEN_EVENT
+}
+
+VOID FspTraceFinalize(VOID)
+{
+#define CLOSE_EVENT(NAME)               \
+    (FspCloseEvent(Fsp ## NAME.Event, Fsp ## NAME.Handle), Fsp ## NAME.Event = 0, Fsp ## NAME.Handle = 0)
+
+    CLOSE_EVENT(LowMemoryCondition);
+    CLOSE_EVENT(LowNonPagedPoolCondition);
+    CLOSE_EVENT(LowPagedPoolCondition);
+
+#undef CLOSE_EVENT
+}
+#endif