[Qemu-devel] [PATCH v5 06/11] qemu-ga: Add Windows VSS provider to quiesce applications on fsfreeze

[Tomoki Sekiyama]

Implements a basic stub of software VSS provider. Currently, this module
only provides a relay function of events between qemu-guest-agent and
Windows VSS when VSS finished filesystem freeze and when qemu snapshot
is done.

In the future, this module could be extended to support the other VSS
functions, such as query for snapshot volumes and recovery.

To build type library (.tlb) for qga-provider.dll from COM IDL (.idl),
VisualC++, MIDL and stdole2.tlb in Windows SDK are required.

This patch also adds pre-compiled .tlb file in the repository in order to
enable cross-compile qemu-ga.exe for Windows with VSS support.

Signed-off-by: Tomoki Sekiyama <address@hidden>
---
 Makefile                                |    2 
 Makefile.objs                           |    2 
 configure                               |    5 
 qga/Makefile.objs                       |    5 
 qga/vss-win32-provider/Makefile.objs    |   23 +
 qga/vss-win32-provider/install.cpp      |  489 ++++++++++++++++++++++++++++++
 qga/vss-win32-provider/provider.cpp     |  513 +++++++++++++++++++++++++++++++
 qga/vss-win32-provider/qga-provider.def |    9 +
 qga/vss-win32-provider/qga-provider.idl |   20 +
 qga/vss-win32-provider/qga-provider.tlb |  Bin
 qga/vss-win32.h                         |   88 +++++
 11 files changed, 1154 insertions(+), 2 deletions(-)
 create mode 100644 qga/vss-win32-provider/Makefile.objs
 create mode 100644 qga/vss-win32-provider/install.cpp
 create mode 100644 qga/vss-win32-provider/provider.cpp
 create mode 100644 qga/vss-win32-provider/qga-provider.def
 create mode 100644 qga/vss-win32-provider/qga-provider.idl
 create mode 100644 qga/vss-win32-provider/qga-provider.tlb
 create mode 100644 qga/vss-win32.h

diff --git a/Makefile b/Makefile
index ec35a15..6b64cfb 100644
--- a/Makefile
+++ b/Makefile
@@ -236,7 +236,7 @@ clean:
        rm -f qemu-options.def
        find . -name '*.[oda]' -type f -exec rm -f {} +
        find . -name '*.l[oa]' -type f -exec rm -f {} +
-       rm -f $(TOOLS) $(HELPERS-y) qemu-ga TAGS cscope.* *.pod *~ */*~
+       rm -f $(filter-out %.tlb,$(TOOLS)) $(HELPERS-y) qemu-ga TAGS cscope.* 
*.pod *~ */*~
        rm -Rf .libs
        rm -f qemu-img-cmds.h
        @# May not be present in GENERATED_HEADERS
diff --git a/Makefile.objs b/Makefile.objs
index 5b288ba..5714820 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -103,6 +103,7 @@ common-obj-y += disas/
 # FIXME: a few definitions from qapi-types.o/qapi-visit.o are needed
 # by libqemuutil.a.  These should be moved to a separate .json schema.
 qga-obj-y = qga/ qapi-types.o qapi-visit.o
+qga-provider-obj-y = qga/
 
 vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS)
 
@@ -114,6 +115,7 @@ nested-vars += \
        stub-obj-y \
        util-obj-y \
        qga-obj-y \
+       qga-provider-obj-y \
        block-obj-y \
        common-obj-y
 dummy := $(call unnest-vars)
diff --git a/configure b/configure
index 6eeda82..88ae51f 100755
--- a/configure
+++ b/configure
@@ -3497,9 +3497,12 @@ if test "$softmmu" = yes ; then
       virtfs=no
     fi
   fi
-  if [ "$linux" = "yes" -o "$bsd" = "yes" -o "$solaris" = "yes" ] ; then
+  if [ "$linux" = "yes" -o "$bsd" = "yes" -o "$solaris" = "yes" -o "$mingw32" 
= "yes" ] ; then
     if [ "$guest_agent" = "yes" ]; then
       tools="qemu-ga\$(EXESUF) $tools"
+      if [ "$mingw32" = "yes" ]; then
+        tools="qga/vss-win32-provider/qga-provider.dll 
qga/vss-win32-provider/qga-provider.tlb $tools"
+      fi
     fi
   fi
 fi
diff --git a/qga/Makefile.objs b/qga/Makefile.objs
index b8d7cd0..245df22 100644
--- a/qga/Makefile.objs
+++ b/qga/Makefile.objs
@@ -3,3 +3,8 @@ qga-obj-$(CONFIG_POSIX) += commands-posix.o channel-posix.o
 qga-obj-$(CONFIG_WIN32) += commands-win32.o channel-win32.o service-win32.o
 qga-obj-y += qapi-generated/qga-qapi-types.o qapi-generated/qga-qapi-visit.o
 qga-obj-y += qapi-generated/qga-qmp-marshal.o
+
+ifeq ($(CONFIG_QGA_VSS),y)
+qga-provider-obj-y += vss-win32-provider/
+$(obj)/vss-win32-requester.o: QEMU_CXXFLAGS += -Wno-unknown-pragmas
+endif
diff --git a/qga/vss-win32-provider/Makefile.objs 
b/qga/vss-win32-provider/Makefile.objs
new file mode 100644
index 0000000..de76edd
--- /dev/null
+++ b/qga/vss-win32-provider/Makefile.objs
@@ -0,0 +1,23 @@
+# rules to build qga-provider.dll
+
+qga-provider-obj-y += provider.o install.o
+
+obj-qga-provider-obj-y = $(addprefix $(obj)/, $(qga-provider-obj-y))
+$(obj-qga-provider-obj-y): QEMU_CXXFLAGS = $(filter-out -Wstrict-prototypes 
-Wmissing-prototypes -Wnested-externs -Wold-style-declaration 
-Wold-style-definition -Wredundant-decls -fstack-protector-all, $(QEMU_CFLAGS)) 
-Wno-unknown-pragmas -Wno-delete-non-virtual-dtor
+
+$(obj)/qga-provider.dll: LDFLAGS = -shared 
-Wl,--add-stdcall-alias,--enable-stdcall-fixup -lole32 -loleaut32 -lshlwapi 
-luuid -static
+$(obj)/qga-provider.dll: $(obj-qga-provider-obj-y) 
$(SRC_PATH)/$(obj)/qga-provider.def
+       $(call quiet-command,$(CXX) -o $@ $(qga-provider-obj-y) 
$(SRC_PATH)/qga/vss-win32-provider/qga-provider.def $(CXXFLAGS) $(LDFLAGS),"  
LINK  $(TARGET_DIR)$@")
+
+
+# rules to build qga-provider.tlb
+# Currently, only native build is supported because building .tlb
+# (TypeLibrary) from .idl requires WindowsSDK and MIDL (and cl.exe in VC++).
+MIDL=$(WIN_SDK)/Bin/midl
+
+$(obj)/qga-provider.tlb: $(SRC_PATH)/$(obj)/qga-provider.idl
+ifeq ($(wildcard $(SRC_PATH)/$(obj)/qga-provider.tlb),)
+       $(call quiet-command,$(MIDL) -tlb $@ -I $(WIN_SDK)/Include $<,"  MIDL  
$(TARGET_DIR)$@")
+else
+       $(call quiet-command,cp $(dir $<)qga-provider.tlb $@, "  COPY  
$(TARGET_DIR)$@")
+endif
diff --git a/qga/vss-win32-provider/install.cpp 
b/qga/vss-win32-provider/install.cpp
new file mode 100644
index 0000000..1695b09
--- /dev/null
+++ b/qga/vss-win32-provider/install.cpp
@@ -0,0 +1,489 @@
+/*
+ * QEMU Guest Agent win32 VSS Provider installer
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <address@hidden>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include "../vss-win32.h"
+#include "inc/win2003/vscoordint.h"
+
+#include <comadmin.h>
+#include <wbemidl.h>
+#include <comdef.h>
+#include <comutil.h>
+
+extern HINSTANCE g_hinstDll;
+
+const GUID CLSID_COMAdminCatalog = { 0xF618C514, 0xDFB8, 0x11d1,
+    {0xA2, 0xCF, 0x00, 0x80, 0x5F, 0xC7, 0x92, 0x35} };
+const GUID IID_ICOMAdminCatalog = { 0xDD662187, 0xDFC2, 0x11d1,
+    {0xA2, 0xCF, 0x00, 0x80, 0x5F, 0xC7, 0x92, 0x35} };
+const GUID CLSID_WbemLocator = { 0x4590f811, 0x1d3a, 0x11d0,
+    {0x89, 0x1f, 0x00, 0xaa, 0x00, 0x4b, 0x2e, 0x24} };
+const GUID IID_IWbemLocator = { 0xdc12a687, 0x737f, 0x11cf,
+    {0x88, 0x4d, 0x00, 0xaa, 0x00, 0x4b, 0x2e, 0x24} };
+
+static void errmsg(DWORD err, const char *text)
+{
+    /*
+     * `text' contains function call statement when errmsg is called via chk().
+     * To make error message more readable, we cut off the text after '('.
+     * If text doesn't contains '(', negative precision is given, which is
+     * treated as though it were missing.
+     */
+    char *msg = NULL, *nul = strchr(text, '(');
+    int len = nul ? nul - text : -1;
+
+    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+                  FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
+                  NULL, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+                  (char *)&msg, 0, NULL);
+    fprintf(stderr, "%.*s. (Error: %lx) %s\n", len, text, err, msg);
+    LocalFree(msg);
+}
+
+static void errmsg_dialog(DWORD err, const char *text, const char *opt = "")
+{
+    char *msg, buf[512];
+
+    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+                  FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
+                  NULL, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+                  (char *)&msg, 0, NULL);
+    snprintf(buf, sizeof(buf), "%s%s. (Error: %lx) %s", text, opt, err, msg);
+    MessageBox(NULL, buf, "Error from " QGA_PROVIDER_NAME, MB_OK|MB_ICONERROR);
+    LocalFree(msg);
+}
+
+#define _chk(hr, status, msg, err_label)        \
+    do {                                        \
+        hr = (status);                          \
+        if (FAILED(hr)) {                       \
+            errmsg(hr, msg);                    \
+            goto err_label;                     \
+        }                                       \
+    } while (0)
+
+#define chk(status) _chk(hr, status, "Failed to " #status, out)
+
+void __stdcall _com_issue_error(HRESULT hr)
+{
+    errmsg(hr, "Unexpected error in COM");
+}
+
+template<class T>
+HRESULT put_Value(ICatalogObject *pObj, LPCWSTR name, T val)
+{
+    return pObj->put_Value(_bstr_t(name), _variant_t(val));
+}
+
+/* Lookup Administrators group name from winmgmt */
+static HRESULT GetAdminName(_bstr_t *name)
+{
+    HRESULT hr;
+    IWbemLocator *pLoc = NULL;
+    IWbemServices *pSvc = NULL;
+    IEnumWbemClassObject *pEnum = NULL;
+    IWbemClassObject *pWobj = NULL;
+    ULONG returned;
+    _variant_t var;
+
+    chk(CoCreateInstance(CLSID_WbemLocator, NULL, CLSCTX_INPROC_SERVER,
+                         IID_IWbemLocator, (LPVOID *)&pLoc));
+    chk(pLoc->ConnectServer(_bstr_t(L"ROOT\\CIMV2"), NULL, NULL, NULL,
+                            0, 0, 0, &pSvc));
+    chk(CoSetProxyBlanket(pSvc, RPC_C_AUTHN_WINNT, RPC_C_AUTHZ_NONE,
+                          NULL, RPC_C_AUTHN_LEVEL_CALL,
+                          RPC_C_IMP_LEVEL_IMPERSONATE, NULL, EOAC_NONE));
+    chk(pSvc->ExecQuery(_bstr_t(L"WQL"),
+                        _bstr_t(L"select * from Win32_Account where "
+                                "SID='S-1-5-32-544' and localAccount=TRUE"),
+                        WBEM_FLAG_RETURN_IMMEDIATELY | WBEM_FLAG_FORWARD_ONLY,
+                        NULL, &pEnum));
+    if (!pEnum) {
+        hr = E_FAIL;
+        errmsg(hr, "Failed to query for Administrators");
+        goto out;
+    }
+    chk(pEnum->Next(WBEM_INFINITE, 1, &pWobj, &returned));
+    if (returned == 0) {
+        hr = E_FAIL;
+        errmsg(hr, "No Administrators found");
+        goto out;
+    }
+
+    chk(pWobj->Get(_bstr_t(L"Name"), 0, &var, 0, 0));
+    try {
+        *name = var;
+    } catch(...) {
+        hr = E_FAIL;
+        errmsg(hr, "Failed to get name of Administrators");
+        goto out;
+    }
+
+out:
+    if (pLoc) {
+        pLoc->Release();
+    }
+    if (pSvc) {
+        pSvc->Release();
+    }
+    if (pEnum) {
+        pEnum->Release();
+    }
+    if (pWobj) {
+        pWobj->Release();
+    }
+    return hr;
+}
+
+
+/* Unregister this module from COM+ Applications Catalog */
+STDAPI COMUnregister(void)
+{
+    HRESULT hr;
+    IUnknown *pUnknown = NULL;
+    ICOMAdminCatalog *pCatalog = NULL;
+    ICatalogCollection *pColl = NULL;
+    ICatalogObject *pObj = NULL;
+    _variant_t var;
+    long i, n;
+
+    DllUnregisterServer();
+
+    CoInitialize(NULL);
+    chk(CoCreateInstance(CLSID_COMAdminCatalog, NULL, CLSCTX_INPROC_SERVER,
+                         IID_IUnknown, (void **)&pUnknown));
+    chk(pUnknown->QueryInterface(IID_ICOMAdminCatalog, (void **)&pCatalog));
+
+    chk(pCatalog->GetCollection(_bstr_t(L"Applications"),
+                                (IDispatch **)&pColl));
+    chk(pColl->Populate());
+
+    chk(pColl->get_Count(&n));
+    for (i = n - 1; i >= 0; i--) {
+        chk(pColl->get_Item(i, (IDispatch **)&pObj));
+        chk(pObj->get_Value(_bstr_t(L"Name"), &var));
+        if (var == _variant_t(QGA_PROVIDER_LNAME)) {
+            fprintf(stderr, "Removing COM+ Application: %S\n",
+                    (wchar_t *)_bstr_t(var));
+            chk(pColl->Remove(i));
+            pObj->Release();
+            pObj = NULL;
+        }
+    }
+    chk(pColl->SaveChanges(&n));
+
+out:
+    if (pUnknown) {
+        pUnknown->Release();
+    }
+    if (pCatalog) {
+        pCatalog->Release();
+    }
+    if (pColl) {
+        pColl->Release();
+    }
+    if (pObj) {
+        pObj->Release();
+    }
+    CoUninitialize();
+
+    return hr;
+}
+
+/* Register this module to COM+ Applications Catalog */
+STDAPI COMRegister(void)
+{
+    HRESULT hr = E_FAIL;
+    IUnknown *pUnknown = NULL;
+    ICOMAdminCatalog *pCatalog = NULL;
+    ICatalogCollection *pApps = NULL, *pRoles = NULL, *pUsersInRole = NULL;
+    ICatalogObject *pObj = NULL;
+    long n;
+    _bstr_t name;
+    _variant_t key;
+    CHAR dllPath[MAX_PATH], tlbPath[MAX_PATH];
+    bool unregisterOnFailure = false;
+
+    if (!g_hinstDll) {
+        errmsg(E_FAIL, "Failed to initialize DLL");
+        return E_FAIL;
+    }
+
+    CoInitialize(NULL);
+    chk(CoCreateInstance(CLSID_COMAdminCatalog, NULL, CLSCTX_INPROC_SERVER,
+                         IID_IUnknown, (void **)&pUnknown));
+    chk(pUnknown->QueryInterface(IID_ICOMAdminCatalog, (void **)&pCatalog));
+
+    /* Install COM+ Component */
+
+    chk(pCatalog->GetCollection(_bstr_t(L"Applications"),
+                                (IDispatch **)&pApps));
+    chk(pApps->Populate());
+    chk(pApps->Add((IDispatch **)&pObj));
+    chk(put_Value(pObj, L"Name",        QGA_PROVIDER_LNAME));
+    chk(put_Value(pObj, L"Description", QGA_PROVIDER_LNAME));
+    chk(put_Value(pObj, L"ApplicationAccessChecksEnabled", true));
+    chk(put_Value(pObj, L"Authentication",                 short(6)));
+    chk(put_Value(pObj, L"AuthenticationCapability",       short(2)));
+    chk(put_Value(pObj, L"ImpersonationLevel",             short(2)));
+    chk(pApps->SaveChanges(&n));
+
+    /* The app should be deleted if something fails after SaveChanges */
+    unregisterOnFailure = true;
+
+    chk(pObj->get_Key(&key));
+    pObj->Release();
+    pObj = NULL;
+
+    if (!GetModuleFileName(g_hinstDll, dllPath, sizeof(dllPath))) {
+        hr = HRESULT_FROM_WIN32(GetLastError());
+        errmsg(hr, "GetModuleFileName failed");
+        goto out;
+    }
+    n = strlen(dllPath);
+    if (n < 3) {
+        hr = E_FAIL;
+        errmsg(hr, "Failed to lookup dll");
+        goto out;
+    }
+    strcpy(tlbPath, dllPath);
+    strcpy(tlbPath+n-3, "tlb");
+    fprintf(stderr, "Registering " QGA_PROVIDER_NAME ":\n");
+    fprintf(stderr, "  %s\n", dllPath);
+    fprintf(stderr, "  %s\n", tlbPath);
+    if (!PathFileExists(tlbPath)) {
+        hr = HRESULT_FROM_WIN32(ERROR_FILE_NOT_FOUND);
+        errmsg(hr, "Failed to lookup tlb");
+        goto out;
+    }
+
+    chk(pCatalog->InstallComponent(_bstr_t(QGA_PROVIDER_LNAME),
+                                   _bstr_t(dllPath), _bstr_t(tlbPath),
+                                   _bstr_t("")));
+
+    /* Setup roles of the applicaion */
+
+    chk(pApps->GetCollection(_bstr_t(L"Roles"), key,
+                             (IDispatch **)&pRoles));
+    chk(pRoles->Populate());
+    chk(pRoles->Add((IDispatch **)&pObj));
+    chk(put_Value(pObj, L"Name",        L"Administrators"));
+    chk(put_Value(pObj, L"Description", L"Administrators group"));
+    chk(pRoles->SaveChanges(&n));
+    chk(pObj->get_Key(&key));
+
+    pObj->Release();
+    pObj = NULL;
+
+    /* Setup users in the role */
+
+    chk(pRoles->GetCollection(_bstr_t(L"UsersInRole"), key,
+                              (IDispatch **)&pUsersInRole));
+    chk(pUsersInRole->Populate());
+
+    chk(pUsersInRole->Add((IDispatch **)&pObj));
+    chk(GetAdminName(&name));
+    chk(put_Value(pObj, L"User", _bstr_t(".\\") + name));
+
+    pObj->Release();
+    pObj = NULL;
+
+    chk(pUsersInRole->Add((IDispatch **)&pObj));
+    chk(put_Value(pObj, L"User", L"SYSTEM"));
+    chk(pUsersInRole->SaveChanges(&n));
+
+out:
+    if (pUnknown) {
+        pUnknown->Release();
+    }
+    if (pCatalog) {
+        pCatalog->Release();
+    }
+    if (pApps) {
+        pApps->Release();
+    }
+    if (pRoles) {
+        pRoles->Release();
+    }
+    if (pUsersInRole) {
+        pUsersInRole->Release();
+    }
+    if (pObj) {
+        pObj->Release();
+    }
+
+    if (unregisterOnFailure && FAILED(hr)) {
+        COMUnregister();
+    }
+    CoUninitialize();
+
+    return hr;
+}
+
+
+static BOOL CreateRegistryKey(LPCTSTR key, LPCTSTR value, LPCTSTR data)
+{
+    HKEY  hKey;
+    LONG  ret;
+    DWORD size;
+
+    ret = RegCreateKeyEx(HKEY_CLASSES_ROOT, key, 0, NULL,
+        REG_OPTION_NON_VOLATILE, KEY_WRITE, NULL, &hKey, NULL);
+    if (ret != ERROR_SUCCESS) {
+        goto out;
+    }
+
+    if (data != NULL) {
+        size = strlen(data) + 1;
+    } else {
+        size = 0;
+    }
+
+    ret = RegSetValueEx(hKey, value, 0, REG_SZ, (LPBYTE)data, size);
+    RegCloseKey(hKey);
+
+out:
+    if (ret != ERROR_SUCCESS) {
+        /* We cannot printf here, and need MessageBox to report an error. */
+        errmsg_dialog(ret, "Cannot add registry ", key);
+        return FALSE;
+    }
+    return TRUE;
+}
+
+/* Register this dll as a VSS provider */
+STDAPI DllRegisterServer(void)
+{
+    IVssAdmin *pVssAdmin = NULL;
+    HRESULT hr = E_FAIL;
+    char dllPath[MAX_PATH];
+    char key[256];
+
+    CoInitialize(NULL);
+
+    if (!g_hinstDll) {
+        errmsg_dialog(hr, "Module instance is not available");
+        goto out;
+    }
+
+    /* Add this module to registery */
+
+    sprintf(key, "CLSID\\%s", g_szClsid);
+    if (!CreateRegistryKey(key, NULL, g_szClsid)) {
+        goto out;
+    }
+
+    if (!GetModuleFileName(g_hinstDll, dllPath, sizeof(dllPath))) {
+        errmsg_dialog(GetLastError(), "GetModuleFileName failed");
+        goto out;
+    }
+
+    sprintf(key, "CLSID\\%s\\InprocServer32", g_szClsid);
+    if (!CreateRegistryKey(key, NULL, dllPath)) {
+        goto out;
+    }
+
+    if (!CreateRegistryKey(key, "ThreadingModel", "Apartment")) {
+        goto out;
+    }
+
+    sprintf(key, "CLSID\\%s\\ProgID", g_szClsid);
+    if (!CreateRegistryKey(key, NULL, g_szProgid)) {
+        goto out;
+    }
+
+    if (!CreateRegistryKey(g_szProgid, NULL, QGA_PROVIDER_NAME)) {
+        goto out;
+    }
+
+    sprintf(key, "%s\\CLSID", g_szProgid);
+    if (!CreateRegistryKey(key, NULL, g_szClsid)) {
+        goto out;
+    }
+
+    hr = CoCreateInstance(CLSID_VSSCoordinator, NULL, CLSCTX_ALL,
+                          IID_IVssAdmin, (void **)&pVssAdmin);
+    if (FAILED(hr)) {
+        errmsg_dialog(hr, "CoCreateInstance(VSSCoordinator) failed");
+        goto out;
+    }
+
+    hr = pVssAdmin->RegisterProvider(g_gProviderId, CLSID_QGAVSSProvider,
+                                     const_cast<WCHAR*>(QGA_PROVIDER_LNAME),
+                                     VSS_PROV_SOFTWARE,
+                                     const_cast<WCHAR*>(QGA_PROVIDER_VERSION),
+                                     g_gProviderVersion);
+    if (FAILED(hr)) {
+        errmsg_dialog(hr, "RegisterProvider failed");
+    }
+
+out:
+    if (pVssAdmin) {
+        pVssAdmin->Release();
+    }
+    CoUninitialize();
+
+    if (FAILED(hr)) {
+        DllUnregisterServer();
+    }
+
+    return hr;
+}
+
+/* Unregister this VSS hardware provider from the system */
+STDAPI DllUnregisterServer(void)
+{
+    TCHAR key[256];
+    IVssAdmin *pVssAdmin = NULL;
+
+    CoInitialize(NULL);
+
+    HRESULT hr = CoCreateInstance(CLSID_VSSCoordinator,
+                                  NULL, CLSCTX_ALL, IID_IVssAdmin,
+                                  (void **)&pVssAdmin);
+    if (SUCCEEDED(hr)) {
+        hr = pVssAdmin->UnregisterProvider(g_gProviderId);
+        pVssAdmin->Release();
+    } else {
+        errmsg_dialog(hr, "CoCreateInstance(VSSCoordinator) failed");
+    }
+
+    sprintf(key, "CLSID\\%s", g_szClsid);
+    SHDeleteKey(HKEY_CLASSES_ROOT, key);
+    SHDeleteKey(HKEY_CLASSES_ROOT, g_szProgid);
+
+    CoUninitialize();
+
+    return S_OK; /* Uninstall should never fail */
+}
+
+
+/* Support function to convert ASCII string into BSTR (used in _bstr_t) */
+namespace _com_util
+{
+    BSTR WINAPI ConvertStringToBSTR(const char *ascii) {
+        int len = strlen(ascii);
+        BSTR bstr = SysAllocStringLen(NULL, len);
+
+        if (!bstr) {
+            return NULL;
+        }
+
+        if (mbstowcs(bstr, ascii, len) == (size_t)-1) {
+            fprintf(stderr, "Failed to convert string '%s' into BSTR", ascii);
+            bstr[0] = 0;
+        }
+        return bstr;
+    }
+}
diff --git a/qga/vss-win32-provider/provider.cpp 
b/qga/vss-win32-provider/provider.cpp
new file mode 100644
index 0000000..d58912b
--- /dev/null
+++ b/qga/vss-win32-provider/provider.cpp
@@ -0,0 +1,513 @@
+/*
+ * QEMU Guest Agent win32 VSS Provider implementations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <address@hidden>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include <stdio.h>
+#include "../vss-win32.h"
+#include "inc/win2003/vscoordint.h"
+#include "inc/win2003/vsprov.h"
+
+#define VSS_TIMEOUT_MSEC (60*1000)
+
+static long g_nComObjsInUse;
+HINSTANCE g_hinstDll;
+
+/* VSS common GUID's */
+
+const CLSID CLSID_VSSCoordinator = { 0xE579AB5F, 0x1CC4, 0x44b4,
+    {0xBE, 0xD9, 0xDE, 0x09, 0x91, 0xFF, 0x06, 0x23} };
+const IID IID_IVssAdmin = { 0x77ED5996, 0x2F63, 0x11d3,
+    {0x8A, 0x39, 0x00, 0xC0, 0x4F, 0x72, 0xD8, 0xE3} };
+
+const IID IID_IVssHardwareSnapshotProvider = { 0x9593A157, 0x44E9, 0x4344,
+    {0xBB, 0xEB, 0x44, 0xFB, 0xF9, 0xB0, 0x6B, 0x10} };
+const IID IID_IVssSoftwareSnapshotProvider = { 0x609e123e, 0x2c5a, 0x44d3,
+    {0x8f, 0x01, 0x0b, 0x1d, 0x9a, 0x47, 0xd1, 0xff} };
+const IID IID_IVssProviderCreateSnapshotSet = { 0x5F894E5B, 0x1E39, 0x4778,
+    {0x8E, 0x23, 0x9A, 0xBA, 0xD9, 0xF0, 0xE0, 0x8C} };
+const IID IID_IVssProviderNotifications = { 0xE561901F, 0x03A5, 0x4afe,
+    {0x86, 0xD0, 0x72, 0xBA, 0xEE, 0xCE, 0x70, 0x04} };
+
+const IID IID_IVssEnumObject = { 0xAE1C7110, 0x2F60, 0x11d3,
+    {0x8A, 0x39, 0x00, 0xC0, 0x4F, 0x72, 0xD8, 0xE3} };
+
+
+void LockModule(BOOL lock)
+{
+    if (lock) {
+        InterlockedIncrement(&g_nComObjsInUse);
+    } else {
+        InterlockedDecrement(&g_nComObjsInUse);
+    }
+}
+
+/* Empty enumerator for VssObject */
+
+class CQGAVSSEnumObject : public IVssEnumObject
+{
+public:
+    STDMETHODIMP QueryInterface(REFIID riid, void **ppObj);
+    STDMETHODIMP_(ULONG) AddRef();
+    STDMETHODIMP_(ULONG) Release();
+
+    /* IVssEnumObject Methods */
+    STDMETHODIMP Next(
+        ULONG celt, VSS_OBJECT_PROP *rgelt, ULONG *pceltFetched);
+    STDMETHODIMP Skip(ULONG celt);
+    STDMETHODIMP Reset(void);
+    STDMETHODIMP Clone(IVssEnumObject **ppenum);
+
+    /* CQGAVSSEnumObject Methods */
+    CQGAVSSEnumObject();
+    ~CQGAVSSEnumObject();
+
+private:
+    long m_nRefCount;
+};
+
+CQGAVSSEnumObject::CQGAVSSEnumObject()
+{
+    m_nRefCount = 0;
+    LockModule(TRUE);
+}
+
+CQGAVSSEnumObject::~CQGAVSSEnumObject()
+{
+    LockModule(FALSE);
+}
+
+STDMETHODIMP CQGAVSSEnumObject::QueryInterface(REFIID riid, void **ppObj)
+{
+    if (riid == IID_IUnknown || riid == IID_IVssEnumObject) {
+        *ppObj = static_cast<void*>(static_cast<IVssEnumObject*>(this));
+        AddRef();
+        return S_OK;
+    }
+    *ppObj = NULL;
+    return E_NOINTERFACE;
+}
+
+STDMETHODIMP_(ULONG) CQGAVSSEnumObject::AddRef()
+{
+    return InterlockedIncrement(&m_nRefCount);
+}
+
+STDMETHODIMP_(ULONG) CQGAVSSEnumObject::Release()
+{
+    long nRefCount = InterlockedDecrement(&m_nRefCount);
+    if (m_nRefCount == 0) {
+        delete this;
+    }
+    return nRefCount;
+}
+
+STDMETHODIMP CQGAVSSEnumObject::Next(
+    ULONG celt, VSS_OBJECT_PROP *rgelt, ULONG *pceltFetched)
+{
+    *pceltFetched = 0;
+    return S_FALSE;
+}
+
+STDMETHODIMP CQGAVSSEnumObject::Skip(ULONG celt)
+{
+    return S_FALSE;
+}
+
+STDMETHODIMP CQGAVSSEnumObject::Reset(void)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVSSEnumObject::Clone(IVssEnumObject **ppenum)
+{
+    return E_NOTIMPL;
+}
+
+
+/* QGAVssProvider */
+
+class CQGAVssProvider :
+    public IVssSoftwareSnapshotProvider,
+    public IVssProviderCreateSnapshotSet,
+    public IVssProviderNotifications
+{
+public:
+    STDMETHODIMP QueryInterface(REFIID riid, void **ppObj);
+    STDMETHODIMP_(ULONG) AddRef();
+    STDMETHODIMP_(ULONG) Release();
+
+    /* IVssSoftwareSnapshotProvider Methods */
+    STDMETHODIMP SetContext(LONG lContext);
+    STDMETHODIMP GetSnapshotProperties(
+        VSS_ID SnapshotId, VSS_SNAPSHOT_PROP *pProp);
+    STDMETHODIMP Query(
+        VSS_ID QueriedObjectId, VSS_OBJECT_TYPE eQueriedObjectType,
+        VSS_OBJECT_TYPE eReturnedObjectsType, IVssEnumObject **ppEnum);
+    STDMETHODIMP DeleteSnapshots(
+        VSS_ID SourceObjectId, VSS_OBJECT_TYPE eSourceObjectType,
+        BOOL bForceDelete, LONG *plDeletedSnapshots,
+        VSS_ID *pNondeletedSnapshotID);
+    STDMETHODIMP BeginPrepareSnapshot(
+        VSS_ID SnapshotSetId, VSS_ID SnapshotId,
+        VSS_PWSZ pwszVolumeName, LONG lNewContext);
+    STDMETHODIMP IsVolumeSupported(
+        VSS_PWSZ pwszVolumeName, BOOL *pbSupportedByThisProvider);
+    STDMETHODIMP IsVolumeSnapshotted(
+        VSS_PWSZ pwszVolumeName, BOOL *pbSnapshotsPresent,
+        LONG *plSnapshotCompatibility);
+    STDMETHODIMP SetSnapshotProperty(
+        VSS_ID SnapshotId, VSS_SNAPSHOT_PROPERTY_ID eSnapshotPropertyId,
+        VARIANT vProperty);
+    STDMETHODIMP RevertToSnapshot(VSS_ID SnapshotId);
+    STDMETHODIMP QueryRevertStatus(VSS_PWSZ pwszVolume, IVssAsync **ppAsync);
+
+    /* IVssProviderCreateSnapshotSet Methods */
+    STDMETHODIMP EndPrepareSnapshots(VSS_ID SnapshotSetId);
+    STDMETHODIMP PreCommitSnapshots(VSS_ID SnapshotSetId);
+    STDMETHODIMP CommitSnapshots(VSS_ID SnapshotSetId);
+    STDMETHODIMP PostCommitSnapshots(
+        VSS_ID SnapshotSetId, LONG lSnapshotsCount);
+    STDMETHODIMP PreFinalCommitSnapshots(VSS_ID SnapshotSetId);
+    STDMETHODIMP PostFinalCommitSnapshots(VSS_ID SnapshotSetId);
+    STDMETHODIMP AbortSnapshots(VSS_ID SnapshotSetId);
+
+    /* IVssProviderNotifications Methods */
+    STDMETHODIMP OnLoad(IUnknown *pCallback);
+    STDMETHODIMP OnUnload(BOOL bForceUnload);
+
+    /* CQGAVssProvider Methods */
+    CQGAVssProvider();
+    ~CQGAVssProvider();
+
+private:
+    long m_nRefCount;
+};
+
+CQGAVssProvider::CQGAVssProvider()
+{
+    m_nRefCount = 0;
+    LockModule(TRUE);
+}
+
+CQGAVssProvider::~CQGAVssProvider()
+{
+    LockModule(FALSE);
+}
+
+STDMETHODIMP CQGAVssProvider::QueryInterface(REFIID riid, void **ppObj)
+{
+    if (riid == IID_IUnknown) {
+        *ppObj = static_cast<void*>(this);
+        AddRef();
+        return S_OK;
+    }
+    if (riid == IID_IVssSoftwareSnapshotProvider) {
+        *ppObj = static_cast<void*>(
+            static_cast<IVssSoftwareSnapshotProvider*>(this));
+        AddRef();
+        return S_OK;
+    }
+    if (riid == IID_IVssProviderCreateSnapshotSet) {
+        *ppObj = static_cast<void*>(
+            static_cast<IVssProviderCreateSnapshotSet*>(this));
+        AddRef();
+        return S_OK;
+    }
+    if (riid == IID_IVssProviderNotifications) {
+        *ppObj = static_cast<void*>(
+            static_cast<IVssProviderNotifications*>(this));
+        AddRef();
+        return S_OK;
+    }
+    *ppObj = NULL;
+    return E_NOINTERFACE;
+}
+
+STDMETHODIMP_(ULONG) CQGAVssProvider::AddRef()
+{
+    return InterlockedIncrement(&m_nRefCount);
+}
+
+STDMETHODIMP_(ULONG) CQGAVssProvider::Release()
+{
+    long nRefCount = InterlockedDecrement(&m_nRefCount);
+    if (m_nRefCount == 0) {
+        delete this;
+    }
+    return nRefCount;
+}
+
+
+/*
+ * IVssSoftwareSnapshotProvider methods
+ */
+
+STDMETHODIMP CQGAVssProvider::SetContext(LONG lContext)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::GetSnapshotProperties(
+    VSS_ID SnapshotId, VSS_SNAPSHOT_PROP *pProp)
+{
+    return VSS_E_OBJECT_NOT_FOUND;
+}
+
+STDMETHODIMP CQGAVssProvider::Query(
+    VSS_ID QueriedObjectId, VSS_OBJECT_TYPE eQueriedObjectType,
+    VSS_OBJECT_TYPE eReturnedObjectsType, IVssEnumObject **ppEnum)
+{
+    try {
+        *ppEnum = new CQGAVSSEnumObject;
+    } catch (...) {
+        return E_OUTOFMEMORY;
+    }
+    (*ppEnum)->AddRef();
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::DeleteSnapshots(
+    VSS_ID SourceObjectId, VSS_OBJECT_TYPE eSourceObjectType,
+    BOOL bForceDelete, LONG *plDeletedSnapshots, VSS_ID *pNondeletedSnapshotID)
+{
+    return E_NOTIMPL;
+}
+
+STDMETHODIMP CQGAVssProvider::BeginPrepareSnapshot(
+    VSS_ID SnapshotSetId, VSS_ID SnapshotId,
+    VSS_PWSZ pwszVolumeName, LONG lNewContext)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::IsVolumeSupported(
+    VSS_PWSZ pwszVolumeName, BOOL *pbSupportedByThisProvider)
+{
+    *pbSupportedByThisProvider = TRUE;
+
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::IsVolumeSnapshotted(VSS_PWSZ pwszVolumeName,
+    BOOL *pbSnapshotsPresent, LONG *plSnapshotCompatibility)
+{
+    *pbSnapshotsPresent = FALSE;
+    *plSnapshotCompatibility = 0;
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::SetSnapshotProperty(VSS_ID SnapshotId,
+    VSS_SNAPSHOT_PROPERTY_ID eSnapshotPropertyId, VARIANT vProperty)
+{
+    return E_NOTIMPL;
+}
+
+STDMETHODIMP CQGAVssProvider::RevertToSnapshot(VSS_ID SnapshotId)
+{
+    return E_NOTIMPL;
+}
+
+STDMETHODIMP CQGAVssProvider::QueryRevertStatus(
+    VSS_PWSZ pwszVolume, IVssAsync **ppAsync)
+{
+    return E_NOTIMPL;
+}
+
+
+/*
+ * IVssProviderCreateSnapshotSet methods
+ */
+
+STDMETHODIMP CQGAVssProvider::EndPrepareSnapshots(VSS_ID SnapshotSetId)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::PreCommitSnapshots(VSS_ID SnapshotSetId)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::CommitSnapshots(VSS_ID SnapshotSetId)
+{
+    HRESULT hr = S_OK;
+    HANDLE hEventFrozen, hEventThaw;
+
+    hEventFrozen = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_FROZEN);
+    if (hEventFrozen == INVALID_HANDLE_VALUE) {
+        return E_FAIL;
+    }
+
+    hEventThaw = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_THAW);
+    if (hEventThaw == INVALID_HANDLE_VALUE) {
+        CloseHandle(hEventFrozen);
+        return E_FAIL;
+    }
+
+    /* Send event to qemu-ga to notify filesystem is frozen */
+    SetEvent(hEventFrozen);
+
+    /* Wait until the snapshot is taken by the host. */
+    if (WaitForSingleObject(hEventThaw, VSS_TIMEOUT_MSEC) != WAIT_OBJECT_0) {
+        hr = E_ABORT;
+    }
+
+    CloseHandle(hEventThaw);
+    CloseHandle(hEventFrozen);
+    return hr;
+}
+
+STDMETHODIMP CQGAVssProvider::PostCommitSnapshots(
+    VSS_ID SnapshotSetId, LONG lSnapshotsCount)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::PreFinalCommitSnapshots(VSS_ID SnapshotSetId)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::PostFinalCommitSnapshots(VSS_ID SnapshotSetId)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::AbortSnapshots(VSS_ID SnapshotSetId)
+{
+    return S_OK;
+}
+
+/*
+ * IVssProviderNotifications methods
+ */
+
+STDMETHODIMP CQGAVssProvider::OnLoad(IUnknown *pCallback)
+{
+    return S_OK;
+}
+
+STDMETHODIMP CQGAVssProvider::OnUnload(BOOL bForceUnload)
+{
+    return S_OK;
+}
+
+
+/*
+ * CQGAVssProviderFactory class
+ */
+
+class CQGAVssProviderFactory : public IClassFactory
+{
+public:
+    STDMETHODIMP QueryInterface(REFIID riid, void **ppv);
+    STDMETHODIMP_(ULONG) AddRef();
+    STDMETHODIMP_(ULONG) Release();
+    STDMETHODIMP CreateInstance(
+        IUnknown *pUnknownOuter, REFIID iid, void **ppv);
+    STDMETHODIMP LockServer(BOOL lock) { return E_NOTIMPL; }
+
+    CQGAVssProviderFactory();
+    ~CQGAVssProviderFactory();
+
+private:
+    long m_nRefCount;
+};
+
+CQGAVssProviderFactory::CQGAVssProviderFactory()
+{
+    m_nRefCount = 0;
+    LockModule(TRUE);
+}
+
+CQGAVssProviderFactory::~CQGAVssProviderFactory()
+{
+    LockModule(FALSE);
+}
+
+STDMETHODIMP CQGAVssProviderFactory::QueryInterface(REFIID riid, void **ppv)
+{
+    if (riid == IID_IUnknown || riid == IID_IClassFactory) {
+        *ppv = static_cast<void*>(this);
+        AddRef();
+        return S_OK;
+    }
+    *ppv = NULL;
+    return E_NOINTERFACE;
+}
+
+STDMETHODIMP_(ULONG) CQGAVssProviderFactory::AddRef()
+{
+    return InterlockedIncrement(&m_nRefCount);
+}
+
+STDMETHODIMP_(ULONG) CQGAVssProviderFactory::Release()
+{
+    long nRefCount = InterlockedDecrement(&m_nRefCount);
+    if (m_nRefCount == 0) {
+        delete this;
+    }
+    return nRefCount;
+}
+
+STDMETHODIMP CQGAVssProviderFactory::CreateInstance(
+    IUnknown *pUnknownOuter, REFIID iid, void **ppv)
+{
+    CQGAVssProvider *pObj;
+
+    if (pUnknownOuter) {
+        return CLASS_E_NOAGGREGATION;
+    }
+    try {
+        pObj = new CQGAVssProvider;
+    } catch (...) {
+        return E_OUTOFMEMORY;
+    }
+    HRESULT hr = pObj->QueryInterface(iid, ppv);
+    if (FAILED(hr)) {
+        delete pObj;
+    }
+    return hr;
+}
+
+
+/*
+ * DLL functions
+ */
+
+STDAPI DllGetClassObject(REFCLSID rclsid, REFIID riid, LPVOID *ppv)
+{
+    CQGAVssProviderFactory *factory;
+    try {
+        factory = new CQGAVssProviderFactory;
+    } catch (...) {
+        return E_OUTOFMEMORY;
+    }
+    factory->AddRef();
+    HRESULT hr = factory->QueryInterface(riid, ppv);
+    factory->Release();
+    return hr;
+}
+
+STDAPI DllCanUnloadNow()
+{
+    return g_nComObjsInUse == 0 ? S_OK : S_FALSE;
+}
+
+EXTERN_C
+BOOL WINAPI DllMain(HINSTANCE hinstDll, DWORD dwReason, LPVOID lpReserved)
+{
+    if (dwReason == DLL_PROCESS_ATTACH) {
+        g_hinstDll = hinstDll;
+        DisableThreadLibraryCalls(hinstDll);
+    }
+    return TRUE;
+}
diff --git a/qga/vss-win32-provider/qga-provider.def 
b/qga/vss-win32-provider/qga-provider.def
new file mode 100644
index 0000000..3181ad8
--- /dev/null
+++ b/qga/vss-win32-provider/qga-provider.def
@@ -0,0 +1,9 @@
+LIBRARY      "QGA-PROVIDER.DLL"
+
+EXPORTS
+       COMRegister             PRIVATE
+       COMUnregister           PRIVATE
+       DllCanUnloadNow         PRIVATE
+       DllGetClassObject       PRIVATE
+       DllRegisterServer       PRIVATE
+       DllUnregisterServer     PRIVATE
diff --git a/qga/vss-win32-provider/qga-provider.idl 
b/qga/vss-win32-provider/qga-provider.idl
new file mode 100644
index 0000000..17abca0
--- /dev/null
+++ b/qga/vss-win32-provider/qga-provider.idl
@@ -0,0 +1,20 @@
+import "oaidl.idl";
+import "ocidl.idl";
+
+[
+    uuid(103B8142-6CE5-48A7-BDE1-794D3192FCF1),
+    version(1.0),
+    helpstring("QGAVSSProvider Type Library")
+]
+library QGAVSSHWProviderLib
+{
+    importlib("stdole2.tlb");
+    [
+        uuid(6E6A3492-8D4D-440C-9619-5E5D0CC31CA8),
+        helpstring("QGAVSSProvider Class")
+    ]
+    coclass QGAVSSHWProvider
+    {
+        [default] interface IUnknown;
+    };
+};
diff --git a/qga/vss-win32-provider/qga-provider.tlb 
b/qga/vss-win32-provider/qga-provider.tlb
new file mode 100644
index 
0000000000000000000000000000000000000000..226452a1861371ffe0cad1019cf90fdfdcd5ef49
GIT binary patch
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gXfrXehlhjmFbIJB4$8MKU>*YlD1Z9^F{m5{03Vre%>V!Z

literal 0
HcmV?d00001

diff --git a/qga/vss-win32.h b/qga/vss-win32.h
new file mode 100644
index 0000000..fd6b4fb
--- /dev/null
+++ b/qga/vss-win32.h
@@ -0,0 +1,88 @@
+/*
+ * QEMU Guest Agent win32 VSS common declarations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <address@hidden>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef VSS_WIN32_H
+#define VSS_WIN32_H
+
+#define __MIDL_user_allocate_free_DEFINED__
+#include "config-host.h"
+#include <windows.h>
+#include <shlwapi.h>
+
+/* Reduce warnings to include vss.h */
+
+/* Ignore annotations for MS IDE */
+#define __in  IN
+#define __out OUT
+#define __RPC_unique_pointer
+#define __RPC_string
+#define __RPC__deref_inout_opt
+#define __RPC__out
+#ifndef __RPC__out_ecount_part
+#define __RPC__out_ecount_part(x, y)
+#endif
+#define _declspec(x)
+#undef uuid
+#define uuid(x)
+
+/* Undef some duplicated error codes redefined in vss.h */
+#undef VSS_E_BAD_STATE
+#undef VSS_E_PROVIDER_NOT_REGISTERED
+#undef VSS_E_PROVIDER_VETO
+#undef VSS_E_OBJECT_NOT_FOUND
+#undef VSS_E_VOLUME_NOT_SUPPORTED
+#undef VSS_E_VOLUME_NOT_SUPPORTED_BY_PROVIDER
+#undef VSS_E_OBJECT_ALREADY_EXISTS
+#undef VSS_E_UNEXPECTED_PROVIDER_ERROR
+#undef VSS_E_INVALID_XML_DOCUMENT
+#undef VSS_E_MAXIMUM_NUMBER_OF_VOLUMES_REACHED
+#undef VSS_E_MAXIMUM_NUMBER_OF_SNAPSHOTS_REACHED
+
+/*
+ * VSS headers must be installed from Microsoft VSS SDK 7.2 available at:
+ * http://www.microsoft.com/en-us/download/details.aspx?id=23490
+ */
+#include "inc/win2003/vss.h"
+
+/* Macros to convert char definitions to wchar */
+#define _L(a) L##a
+#define L(a) _L(a)
+
+/* Constants for QGA VSS Provider */
+
+#define QGA_PROVIDER_NAME "QEMU Guest Agent VSS Provider"
+#define QGA_PROVIDER_LNAME L(QGA_PROVIDER_NAME)
+#define QGA_PROVIDER_VERSION L(QEMU_VERSION)
+
+#define EVENT_NAME_FROZEN "Global\\QGAVSSEvent-frozen"
+#define EVENT_NAME_THAW   "Global\\QGAVSSEvent-thaw"
+
+#define QGA_PROVIDER_DLL "qga-provider.dll"
+
+const GUID g_gProviderId = { 0x3629d4ed, 0xee09, 0x4e0e,
+    {0x9a, 0x5c, 0x6d, 0x8b, 0xa2, 0x87, 0x2a, 0xef} };
+const GUID g_gProviderVersion = { 0x11ef8b15, 0xcac6, 0x40d6,
+    {0x8d, 0x5c, 0x8f, 0xfc, 0x16, 0x3f, 0x24, 0xca} };
+
+const CLSID CLSID_QGAVSSProvider = { 0x6e6a3492, 0x8d4d, 0x440c,
+    {0x96, 0x19, 0x5e, 0x5d, 0x0c, 0xc3, 0x1c, 0xa8} };
+
+const TCHAR g_szClsid[] = TEXT("{6E6A3492-8D4D-440C-9619-5E5D0CC31CA8}");
+const TCHAR g_szProgid[] = TEXT("QGAVSSProvider");
+
+/* Enums undefined in VSS SDK 7.2 but defined in newer Windows SDK */
+enum __VSS_VOLUME_SNAPSHOT_ATTRIBUTES {
+    VSS_VOLSNAP_ATTR_NO_AUTORECOVERY       = 0x00000002,
+    VSS_VOLSNAP_ATTR_TXF_RECOVERY          = 0x02000000
+};
+
+#endif