qemu-ga: fsfreeze on Windows using VSS

Add configuration for c++ compiler (${cross_prefix}g++ as default) in configure and Makefiles.

Currently, usage of c++ language is only for access to Windows VSS using COM+ services in qemu-guest-agent for Windows.

Signed-off-by Tomoki Sekiyama <[email protected]>

---
 configure |   13 +++++++++++++
 rules.mak |    9 ++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

configure +13 -0

index 1654413..a2fc3f3 100755
@@ -251,6 +251,8 @@ for opt do
   ;;
   --cc=*) CC="$optarg"
   ;;
+  --cxx=*) CXX="$optarg"
+  ;;
   --source-path=*) source_path="$optarg"
   ;;
   --cpu=*) cpu="$optarg"

@@ -281,6 +283,12 @@ else
   cc="${CC-${cross_prefix}gcc}"
 fi
 
+if test -z "${CXX}${cross_prefix}"; then
+  cxx="c++"
+else
+  cxx="${CXX-${cross_prefix}g++}"
+fi
+
 ar="${AR-${cross_prefix}ar}"
 as="${AS-${cross_prefix}as}"
 cpp="${CPP-$cc -E}"

@@ -614,6 +622,8 @@ for opt do
   ;;
   --host-cc=*) host_cc="$optarg"
   ;;
+  --cxx=*) cxx="$optarg"
+  ;;
   --objcc=*) objcc="$optarg"
   ;;
   --make=*) make="$optarg"

@@ -1015,6 +1025,7 @@ echo "  --cross-prefix=PREFIX    use PREFIX for compile tools [$cross_prefix]"
 echo "  --cc=CC                  use C compiler CC [$cc]"
 echo "  --host-cc=CC             use C compiler CC [$host_cc] for code run at"
 echo "                           build time"
+echo "  --cxx=CXX                use C++ compiler CXX [$cxx]"
 echo "  --objcc=OBJCC            use Objective-C compiler OBJCC [$objcc]"
 echo "  --extra-cflags=CFLAGS    append extra C compiler flags QEMU_CFLAGS"
 echo "  --extra-ldflags=LDFLAGS  append extra linker flags LDFLAGS"

@@ -3459,6 +3470,7 @@ fi
 echo "Source path       $source_path"
 echo "C compiler        $cc"
 echo "Host C compiler   $host_cc"
+echo "C++ compiler      $cxx"
 echo "Objective-C compiler $objcc"
 echo "CFLAGS            $CFLAGS"
 echo "QEMU_CFLAGS       $QEMU_CFLAGS"

@@ -4036,6 +4048,7 @@ echo "PYTHON=$python" >> $config_host_mak
 echo "CC=$cc" >> $config_host_mak
 echo "CC_I386=$cc_i386" >> $config_host_mak
 echo "HOST_CC=$host_cc" >> $config_host_mak
+echo "CXX=$cxx" >> $config_host_mak
 echo "OBJCC=$objcc" >> $config_host_mak
 echo "AR=$ar" >> $config_host_mak
 echo "AS=$as" >> $config_host_mak

rules.mak +7 -0

index 4499745..abc2e84 100644
@@ -8,9 +8,13 @@ MAKEFLAGS += -rR
 %.d:
 %.h:
 %.c:
+%.cpp:
 %.m:
 %.mak:
 
+# Flags for C++ compilation
+QEMU_CXXFLAGS = -D__STDC_LIMIT_MACROS $(filter-out -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Wold-style-declaration -Wold-style-definition -Wredundant-decls, $(QEMU_CFLAGS))
+
 # Flags for dependency generation
 QEMU_DGFLAGS += -MMD -MP -MT $@ -MF $(*D)/$(*F).d
 

@@ -50,6 +54,9 @@ endif
 %.o: %.asm
 	$(call quiet-command,$(AS) $(ASFLAGS) -o $@ $<,"  AS    $(TARGET_DIR)$@")
 
+%.o: %.cpp
+	$(call quiet-command,$(CXX) $(QEMU_INCLUDES) $(QEMU_CXXFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c -o $@ $<,"  CXX   $(TARGET_DIR)$@")
+
 %.o: %.m
 	$(call quiet-command,$(OBJCC) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c -o $@ $<,"  OBJC  $(TARGET_DIR)$@")
 

Add configuration for c++ compiler (${cross_prefix}g++ as default) in configure and Makefiles.

Currently, usage of c++ language is only for access to Windows VSS using COM+ services in qemu-guest-agent for Windows.

Signed-off-by Tomoki Sekiyama <[email protected]>

---
 configure |   13 +++++++++++++
 rules.mak |    9 ++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

Add c++ keywords to avoid errors in compiling with c++ compiler. This also renames class member of PciDeviceInfo to q_class.

Signed-off-by Tomoki Sekiyama <[email protected]>

---
 hmp.c           |    2 +-
 hw/pci/pci.c    |    2 +-
 scripts/qapi.py |   12 +++++++++++-
 3 files changed, 13 insertions(+), 3 deletions(-)

Enable checkpatch.pl to apply the same checks as C source files for C++ files with .cpp extensions. It also adds some exceptions for C++ sources to suppress errors for:
- <> used in C++ template arguments (e.g. template <class T>)

  - :: used to represent namespaces   (e.g. SomeClass::method())
  - : used in class declaration       (e.g. class T : public Super)
  - ~ used in destructor method name  (e.g. T::~T())

Signed-off-by Tomoki Sekiyama <[email protected]>

---
 scripts/checkpatch.pl |   34 ++++++++++++++++++++++++++--------
 1 file changed, 26 insertions(+), 8 deletions(-)

Review

Quoted 5 lines

(quoted diff) +4 -0

+if ! command -v msiextract > /dev/null; then
+  echo 'msiextract not found. Please install msitools.' >&2
+  exit 1
+fi

(This is not a review comment -- I'm trying to test it:)

What msiextract version (and dependencies, like libgcab, libgsf etc) are you using? I'm unable to extract "vsssdk.msi"; msiextract spews a bunch of assertion failures.

2e39646b7850a12673bc66ade85fece3 setup.exe
433eb024ed0c669dd1563d952ca41091 vsssdk.msi

My versions (RHEL-6.4.z distro):
- msitools-0.92 (built from source)
- gcab-0.4 (built from source)
- libgsf-1.14.15-5.el6 (patch in [1] doesn't seem to help, it only changes the kinds of asserts that fail)
- glib2-2.22.5-7.el6
- libuuid-2.17.2-12.9.el6_4.3

From 0eee72d26d06d7087d5d83efbc37564f67489019 Mon Sep 17 00:00:00 2001

Il 25/06/2013 17:01, Laszlo Ersek ha scritto:

Quoted 16 lines · Tomoki Sekiyama

Review

Quoted 5 lines

(quoted diff) +4 -0

+if ! command -v msiextract > /dev/null; then
+  echo 'msiextract not found. Please install msitools.' >&2
+  exit 1
+fi

(This is not a review comment -- I'm trying to test it:)

What msiextract version (and dependencies, like libgcab, libgsf etc) are you using? I'm unable to extract "vsssdk.msi"; msiextract spews a bunch of assertion failures.

2e39646b7850a12673bc66ade85fece3 setup.exe
433eb024ed0c669dd1563d952ca41091 vsssdk.msi

Quoted 7 lines

My versions (RHEL-6.4.z distro):
- msitools-0.92 (built from source)
- gcab-0.4 (built from source)
- libgsf-1.14.15-5.el6 (patch in [1] doesn't seem to help, it only changes the kinds of asserts that fail)
- glib2-2.22.5-7.el6
- libuuid-2.17.2-12.9.el6_4.3

The attached patch may help building a newer libgsf on RHEL6.

To enable VSS support in qemu-ga for Windows, header files included in VSS SDK are required.
The VSS support is enabled by the configure option like below:
./configure --with-vss-sdk="/path/to/VSS SDK"

If the path is omitted, it tries to search the headers from default paths and VSS support is enabled only if the SDK is found.
VSS support is disabled if --without-vss-sdk or --with-vss-sdk=no is specified.

VSS SDK is available from:
http://www.microsoft.com/en-us/download/details.aspx?id=23490

To cross-compile using mingw, you need to setup the SDK on Windows environments to extract headers. You can also extract the SDK headers on POSIX environments using scripts/extract-vss-headers and msitools.

In addition, --with-win-sdk="/path/to/Windows SDK" option is also added to specify path to Windows SDK, which may be used for native-compile of .tlb file of qemu-ga VSS provider. However, this is usually unnecessary because pre-compiled .tlb file is included.

Signed-off-by Tomoki Sekiyama <[email protected]>

---
 .gitignore |    1 +
 Makefile   |    1 +
 configure  |   69 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 71 insertions(+)

Quoted 10 lines · Tomoki Sekiyama

To enable VSS support in qemu-ga for Windows, header files included in VSS SDK are required.
The VSS support is enabled by the configure option like below:
./configure --with-vss-sdk="/path/to/VSS SDK"

If the path is omitted, it tries to search the headers from default paths and VSS support is enabled only if the SDK is found.
VSS support is disabled if --without-vss-sdk or --with-vss-sdk=no is specified.

Quoted 6 lines

VSS SDK is available from:
http://www.microsoft.com/en-us/download/details.aspx?id=23490

To cross-compile using mingw, you need to setup the SDK on Windows environments to extract headers. You can also extract the SDK headers on POSIX environments using scripts/extract-vss-headers and msitools.

Quoted 14 lines · Tomoki Sekiyama

Quoted 13 lines

To enable VSS support in qemu-ga for Windows, header files included in VSS SDK are required.
The VSS support is enabled by the configure option like below:
./configure --with-vss-sdk="/path/to/VSS SDK"

If the path is omitted, it tries to search the headers from default paths and VSS support is enabled only if the SDK is found.
VSS support is disabled if --without-vss-sdk or --with-vss-sdk=no is specified.

VSS SDK is available from:
http://www.microsoft.com/en-us/download/details.aspx?id=23490

Quoted 3 lines

Quoted 3 lines

To cross-compile using mingw, you need to setup the SDK on Windows environments to extract headers. You can also extract the SDK headers on POSIX environments using scripts/extract-vss-headers and msitools.

What is the license of the VSS SDK ? In particular is the license compatible with QEMU to allow us to link to it from GPL code ?

Il 28/06/2013 12:43, Daniel P. Berrange ha scritto:

Quoted 15 lines · Laszlo Ersek

Quoted 14 lines · Tomoki Sekiyama

Quoted 13 lines

To enable VSS support in qemu-ga for Windows, header files included in VSS SDK are required.
The VSS support is enabled by the configure option like below:
./configure --with-vss-sdk="/path/to/VSS SDK"

If the path is omitted, it tries to search the headers from default paths and VSS support is enabled only if the SDK is found.
VSS support is disabled if --without-vss-sdk or --with-vss-sdk=no is specified.

VSS SDK is available from:
http://www.microsoft.com/en-us/download/details.aspx?id=23490

Quoted 6 lines

Quoted 3 lines

Quoted 3 lines

To cross-compile using mingw, you need to setup the SDK on Windows environments to extract headers. You can also extract the SDK headers on POSIX environments using scripts/extract-vss-headers and msitools.

What is the license of the VSS SDK ? In particular is the license compatible with QEMU to allow us to link to it from GPL code ?

Doesn't it fall under the "operating system component" exception?

Quoted 4 lines

Quoted 2 lines

What is the license of the VSS SDK ? In particular is the license compatible with QEMU to allow us to link to it from GPL code ?

Doesn't it fall under the "operating system component" exception?

Maybe, maybe no. I think it depends what the VSS SDK actually includes.

IANAL, but my interpretation is that the exception would only apply to stuff that is distributed as part of the base Windows install. Since this is a separate download from Microsoft, it isn't clear to me that the exception would apply in this case.

Does the VSS SDK actually include the .dll library that qemu-ga would be linking aginst, or is the .dll part of base windows install, and VSS SDK merely includes the header files needed for compilation ?

Il 28/06/2013 13:01, Daniel P. Berrange ha scritto:

Quoted 7 lines

Quoted 4 lines

Quoted 2 lines

What is the license of the VSS SDK ? In particular is the license compatible with QEMU to allow us to link to it from GPL code ?

Doesn't it fall under the "operating system component" exception?

Maybe, maybe no. I think it depends what the VSS SDK actually includes.

Quoted 8 lines

IANAL, but my interpretation is that the exception would only apply to stuff that is distributed as part of the base Windows install. Since this is a separate download from Microsoft, it isn't clear to me that the exception would apply in this case.

Does the VSS SDK actually include the .dll library that qemu-ga would be linking aginst, or is the .dll part of base windows install, and VSS SDK merely includes the header files needed for compilation ?

Only the headers, the IDL files, and the "import libraries":

Program Files/Microsoft/VSSSDK72/lib/winxp/obj/i386/vss_uuid.lib Program Files/Microsoft/VSSSDK72/lib/winxp/obj/i386/vssapi.lib Program Files/Microsoft/VSSSDK72/lib/win2003/obj/ia64/vss_uuid.lib Program Files/Microsoft/VSSSDK72/lib/win2003/obj/ia64/vssapi.lib Program Files/Microsoft/VSSSDK72/lib/win2003/obj/i386/vssapi.lib Program Files/Microsoft/VSSSDK72/lib/win2003/obj/i386/vss_uuid.lib Program Files/Microsoft/VSSSDK72/lib/win2003/obj/amd64/vss_uuid.lib Program Files/Microsoft/VSSSDK72/lib/win2003/obj/amd64/vssapi.lib Program Files/Microsoft/VSSSDK72/inc/winxp/vss.h
Program Files/Microsoft/VSSSDK72/inc/winxp/vswriter.h Program Files/Microsoft/VSSSDK72/inc/winxp/vsbackup.h Program Files/Microsoft/VSSSDK72/inc/win2003/vdslun.h Program Files/Microsoft/VSSSDK72/inc/win2003/vswriter.h Program Files/Microsoft/VSSSDK72/inc/win2003/vsmgmt.h Program Files/Microsoft/VSSSDK72/inc/win2003/vscoordint.h Program Files/Microsoft/VSSSDK72/inc/win2003/vscoordint.idl Program Files/Microsoft/VSSSDK72/inc/win2003/vsswprv.idl

Program Files/Microsoft/VSSSDK72/inc/win2003/vsswprv.h Program Files/Microsoft/VSSSDK72/inc/win2003/vss.idl Program Files/Microsoft/VSSSDK72/inc/win2003/vss.h Program Files/Microsoft/VSSSDK72/inc/win2003/vdslun.idl Program Files/Microsoft/VSSSDK72/inc/win2003/vsbackup.h Program Files/Microsoft/VSSSDK72/inc/win2003/vsprov.idl Program Files/Microsoft/VSSSDK72/inc/win2003/vsprov.h Program Files/Microsoft/VSSSDK72/inc/win2003/vsmgmt.idl

Quoted 4 lines

Quoted 3 lines

Quoted 3 lines

Does the VSS SDK actually include the .dll library that qemu-ga would be linking aginst, or is the .dll part of base windows install, and VSS SDK merely includes the header files needed for compilation ?

Quoted 1 line

Only the headers, the IDL files, and the "import libraries":

That sounds more reasonable then from the POV of the gpl system components exception.

BTW, I notice that mingw64 includes the vss.h header and vssapi.a library, so I wonder if that's sufficient to compile this code, without needing to use the VSS SDK download at all.

Quoted 14 lines · Laszlo Ersek

Quoted 13 lines · Tomoki Sekiyama

To enable VSS support in qemu-ga for Windows, header files included in VSS SDK are required.
The VSS support is enabled by the configure option like below:
./configure --with-vss-sdk="/path/to/VSS SDK"

If the path is omitted, it tries to search the headers from default paths and VSS support is enabled only if the SDK is found.
VSS support is disabled if --without-vss-sdk or --with-vss-sdk=no is specified.

VSS SDK is available from:
http://www.microsoft.com/en-us/download/details.aspx?id=23490

Quoted 3 lines

Quoted 3 lines

To cross-compile using mingw, you need to setup the SDK on Windows environments to extract headers. You can also extract the SDK headers on POSIX environments using scripts/extract-vss-headers and msitools.

What is the license of the VSS SDK ? In particular is the license compatible with QEMU to allow us to link to it from GPL code ?

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 <[email protected]>

---
 configure                               |    5
 Makefile                                |    2
 Makefile.objs                           |    2
 qga/Makefile.objs                       |    6
 qga/vss-win32-provider/Makefile.objs    |   24 ++
 create mode 100644 qga/vss-win32-provider/Makefile.objs

configure +0 -0

index cafe830..8e45fad 100755
@@ -3490,9 +3490,12 @@ if test "$softmmu" = yes ; then
       virtfs=no
     fi
   fi

Makefile.objs +1 -0

index 286ce06..b6c1505 100644
@@ -102,6 +102,7 @@ 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-prv-obj-y = qga/
 
 vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS)
 

qga/vss-win32-provider/Makefile.objs new file +1 -0

new file mode 100644
index 0000000..1fe1f8f
@@ -0,0 +1,24 @@
+# rules to build qga-provider.dll

 qga/vss-win32-provider.h                |   26 ++
 qga/vss-win32-provider/install.cpp      |  493 +++++++++++++++++++++++++++++++
 qga/vss-win32-provider/provider.cpp     |  479 ++++++++++++++++++++++++++++++
 qga/vss-win32-provider/qga-provider.def |   10 +
 qga/vss-win32-provider/qga-provider.idl |   20 +
 qga/vss-win32-provider/qga-provider.tlb |  Bin
 qga/vss-win32.h                         |   86 +++++
 12 files changed, 1151 insertions(+), 2 deletions(-)
 create mode 100644 qga/vss-win32-provider.h
 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

qga/vss-win32-provider.h new file +26 -0

new file mode 100644
index 0000000..a437e71
@@ -0,0 +1,26 @@
+/*
+ * QEMU Guest Agent win32 VSS provider declarations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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_PROVIDER_H
+#define VSS_WIN32_PROVIDER_H
+
+#include <windows.h>
+
+STDAPI VSSCheckOSVersion(void);
+
+STDAPI COMRegister(void);
+STDAPI COMUnregister(void);
+
+STDAPI DllRegisterServer(void);
+STDAPI DllUnregisterServer(void);
+
+#endif

qga/vss-win32-provider/install.cpp new file +493 -0

new file mode 100644
index 0000000..d6f1d55
@@ -0,0 +1,493 @@
+/*
+ * QEMU Guest Agent win32 VSS Provider installer
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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 "../vss-win32-provider.h"
+
+#include <comadmin.h>
+#include <wbemidl.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)
+{
+    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);
+    printf("%.*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\n", 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)
+
+template<class T>
+HRESULT put_Value(ICatalogObject *pObj, LPCWSTR name, T val)
+{
+    return pObj->put_Value(_bstr_t(name), _variant_t(val));
+}
+
+/* Check whether this OS version supports VSS providers */
+STDAPI VSSCheckOSVersion(void)
+{
+    OSVERSIONINFO OSver;
+
+    OSver.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
+    GetVersionEx(&OSver);
+    if ((OSver.dwMajorVersion == 5 && OSver.dwMinorVersion >= 2) ||
+       OSver.dwMajorVersion > 5) {
+        return S_OK;
+    }
+    return S_FALSE;
+}
+
+/* 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) {
+        errmsg(E_FAIL, "Failed to query for Administrators");
+        goto out;
+    }
+    chk(pEnum->Next(WBEM_INFINITE, 1, &pWobj, &returned));
+    if (returned == 0) {
+        errmsg(E_FAIL, "Failed to query for Administrators");
+        goto out;
+    }
+
+    chk(pWobj->Get(_bstr_t(L"Name"), 0, &var, 0, 0));
+    name = var;
+out:
+    if (pLoc) {
+        pLoc->Release();
+    }
+    if (pSvc) {
+        pSvc->Release();
+    }
+    if (pEnum) {
+        pEnum->Release();
+    }
+    if (pWobj) {
+        pWobj->Release();
+    }
+    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];
+
+    if (!g_hinstDll) {
+        errmsg(E_FAIL, "Failed to initialize DLL");
+        goto out;
+    }
+
+    if (VSSCheckOSVersion() == S_FALSE) {
+        printf("VSS provider is not supported in this OS version.\n");
+        return S_FALSE; /* VSS feature is disabled */
+    }
+
+    COMUnregister();
+
+    chk(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));
+    chk(pObj->get_Key(&key));
+
+    pObj->Release();
+    pObj = NULL;
+
+    if (!GetModuleFileName(g_hinstDll, dllPath, sizeof(dllPath))) {
+        errmsg(GetLastError(), "GetModuleFileName failed");
+        goto out;
+    }
+    n = strlen(dllPath);
+    if (n < 3) {
+        errmsg(E_FAIL, "Failed to lookup dll");
+    }
+    strcpy(tlbPath, dllPath);
+    strcpy(tlbPath+n-3, "TLB");
+    printf("Registering " QGA_PROVIDER_NAME ":\n");
+    printf("  %s\n", dllPath);
+    printf("  %s\n", tlbPath);
+    if (!PathFileExists(tlbPath)) {
+        errmsg(ERROR_FILE_NOT_FOUND, "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 (FAILED(hr)) {
+        COMUnregister();
+    }
+    CoUninitialize();
+
+    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;
+
+    if (VSSCheckOSVersion() == S_FALSE) {
+        printf("VSS provider is not supported in this OS version.\n");
+        return S_FALSE; /* VSS feature is disabled */
+    }
+
+    chk(DllUnregisterServer());
+
+    chk(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)) {
+            printf("Removing COM+ Application: %S\n", (wchar_t *)_bstr_t(var));
+            chk(pColl->Remove(i));
+        }
+    }
+    chk(pColl->SaveChanges(&n));
+
+out:
+    if (pUnknown) {
+        pUnknown->Release();
+    }
+    if (pCatalog) {
+        pCatalog->Release();
+    }
+    if (pColl) {
+        pColl->Release();
+    }
+    if (pObj) {
+        pObj->Release();
+    }
+    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 = (lstrlen(data) + 1) * sizeof(TCHAR);
+    } 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;
+    }
+
+    sprintf(key, "CLSID\\%s\\InprocServer32", g_szClsid);
+    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");
+        goto out;
+    }
+
+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 functions for _bstr_t in MinGW: Originally written by: Diaa Sami */
+
+void __stdcall _com_issue_error(HRESULT hr)
+{
+    printf("_com_issue_error() called with parameter HRESULT = %lu", hr);
+}
+
+namespace _com_util
+{
+    char * __stdcall ConvertBSTRToString(BSTR bstr)
+    {
+        const unsigned int stringLength = lstrlenW(bstr);
+        char *const ascii = new char [stringLength + 1];
+
+        wcstombs(ascii, bstr, stringLength + 1);
+
+        return ascii;
+    }
+
+    BSTR __stdcall ConvertStringToBSTR(const char *const ascii)
+    {
+        const unsigned int stringLength = lstrlenA(ascii);
+        BSTR bstr = SysAllocStringLen(NULL, stringLength);
+
+        mbstowcs(bstr, ascii, stringLength + 1);
+
+        return bstr;
+    }
+}

qga/vss-win32-provider/provider.cpp new file +479 -0

new file mode 100644
index 0000000..90a3d25
@@ -0,0 +1,479 @@
+/*
+ * QEMU Guest Agent win32 VSS Provider implementations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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"
+
+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 block)
+{
+    if (block) {
+        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;
+    } else if (riid == IID_IVssSoftwareSnapshotProvider) {
+        *ppObj = static_cast<void*>(
+            static_cast<IVssSoftwareSnapshotProvider*>(this));
+        AddRef();
+        return S_OK;
+    } else if (riid == IID_IVssProviderCreateSnapshotSet) {
+        *ppObj = static_cast<void*>(
+            static_cast<IVssProviderCreateSnapshotSet*>(this));
+        AddRef();
+        return S_OK;
+    } else 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)
+{
+    *ppEnum = new CQGAVSSEnumObject;
+    (*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)
+{
+    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 S_OK;
+}
+
+
+/*
+ * 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 hEvent, hEvent2;
+
+    hEvent = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_FROZEN);
+    if (hEvent == INVALID_HANDLE_VALUE) {
+        hr = E_FAIL;
+        goto out;
+    }
+
+    hEvent2 = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_THAW);
+    if (hEvent == INVALID_HANDLE_VALUE) {
+        CloseHandle(hEvent);
+        hr = E_FAIL;
+        goto out;
+    }
+
+    SetEvent(hEvent);
+    if (WaitForSingleObject(hEvent2, 60*1000) != WAIT_OBJECT_0) {
+        hr = E_ABORT;
+    }
+
+    CloseHandle(hEvent2);
+    CloseHandle(hEvent);
+out:
+    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 bLock) { return E_NOTIMPL; }
+private:
+    long m_nRefCount;
+};
+
+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()
+{
+    LockModule(TRUE);
+    return 2;
+}
+
+STDMETHODIMP_(ULONG) CQGAVssProviderFactory::Release()
+{
+    LockModule(FALSE);
+    return 1;
+}
+
+STDMETHODIMP CQGAVssProviderFactory::CreateInstance(
+    IUnknown *pUnknownOuter, REFIID iid, void **ppv)
+{
+    if (pUnknownOuter) {
+        return CLASS_E_NOAGGREGATION;
+    }
+    CQGAVssProvider *pObj = new CQGAVssProvider;
+    if (!pObj) {
+        return E_OUTOFMEMORY;
+    }
+    return pObj->QueryInterface(iid, ppv);
+}
+
+
+/*
+ * DLL functions
+ */
+
+STDAPI DllGetClassObject(REFCLSID rclsid, REFIID riid, LPVOID *ppv)
+{
+    static CQGAVssProviderFactory factory;
+
+    *ppv = NULL;
+    if (IsEqualCLSID(rclsid, CLSID_QGAVSSProvider)) {
+        return factory.QueryInterface(riid, ppv);
+    }
+    return CLASS_E_CLASSNOTAVAILABLE;
+}
+
+STDAPI DllCanUnloadNow()
+{
+    return g_nComObjsInUse == 0 ? S_OK : S_FALSE;
+}
+
+EXTERN_C
+BOOL WINAPI DllMain(HINSTANCE hinstDll, DWORD dwReason, LPVOID lpReserved)
+{
+    switch (dwReason) {
+
+    case DLL_PROCESS_ATTACH:
+        g_hinstDll = hinstDll;
+        DisableThreadLibraryCalls(hinstDll);
+        break;
+    }
+
+    return TRUE;
+}

qga/vss-win32-provider/qga-provider.def new file +10 -0

new file mode 100644
index 0000000..9f3afc8
@@ -0,0 +1,10 @@
+LIBRARY      "QGA-PROVIDER.DLL"
+
+EXPORTS
+	VSSCheckOSVersion	PRIVATE
+	COMRegister		PRIVATE
+	COMUnregister		PRIVATE
+	DllCanUnloadNow		PRIVATE
+	DllGetClassObject	PRIVATE
+	DllRegisterServer	PRIVATE
+	DllUnregisterServer	PRIVATE

qga/vss-win32-provider/qga-provider.idl new file +20 -0

new file mode 100644
index 0000000..17abca0
@@ -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;
+    };
+};

qga/vss-win32-provider/qga-provider.tlb new file binary +0 -0

new file mode 100644
index 0000000000000000000000000000000000000000..226452a1861371ffe0cad1019cf90fdfdcd5ef49
GIT binary patch

qga/vss-win32.h new file +86 -0

new file mode 100644
index 0000000..21655cf
@@ -0,0 +1,86 @@
+/*
+ * QEMU Guest Agent win32 VSS common declarations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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"
+
+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

Quoted 8 lines

Makefile.objs nested-vars += \ · line 120

Quoted 8 lines

Makefile.objs +1 -0

@@ -113,6 +114,7 @@ nested-vars += \
 	stub-obj-y \
 	util-obj-y \
 	qga-obj-y \
+	qga-prv-obj-y \
 	block-obj-y \
 	common-obj-y
 dummy := $(call unnest-vars)

What does this do? Does "qga-prv-obj-y" stand for "all objects under 'qga'"?

Or does it mean "look into qga/Makefile.objs for further objects"?

qga/Makefile.objs qga-obj-$(CONFIG_POSIX) += commands-posix.o channel-posix.o · line 11

Quoted 3 lines

qga/Makefile.objs +3 -0

+qga-obj-y += vss-win32-provider/
+qga-prv-obj-y += vss-win32-provider/
+endif

So we're probably just saying "look into vss-win32-provider/Makefile.objs for further object files", for both variables.

Looks like "qga-prv-obj-y" consists of nothing more than "provider.o" and "install.o", and that "qga-provider.dll" depends on them. In theory, would it be possible *not* to introduce "qga-prv-obj-y" in the higher-level Makefile.obj files, only here?

Why does "qga-provider.dll" depend on ""qga-provider.tlb"? It is not used in the link command.

Also, why is it necessary to collect the files "provider.o", "install.o" and "qga-provider.def" into a DLL, and link qemu-ga.exe against that DLL (via qga-obj-y)? Is this a VSS requirement? Can't we simply link these objects into qemu-ga.exe statically, like the rest of "qga-obj-y"?

I'm trying to wrap my head around the build changes first.

Quoted 16 lines

configure +0 -1

index cafe830..8e45fad 100755
@@ -3490,9 +3490,12 @@ 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"

configure +2 -0

+      if [ "$mingw32" = "yes" ]; then
+        tools="qga/vss-win32-provider/qga-provider.dll

Quoted 5 lines

qga/vss-win32-provider/qga-provider.tlb $tools"
+ fi
fi
fi
fi

This adds three targets to "tools" on mingw32 -- "qemu-ga" hasn't been there until now. Is this actually a small, unrelated bugfix?

I'm asking because I build upstream qemu-ga.exe on my RHEL-6 laptop as follows -- I don't have pixman installed, and configure forces me to specify --disable-tools as well:

$ ./configure --without-pixman --disable-system --disable-tools \
     --cross-prefix=i686-pc-mingw32-
$ make qemu-ga.exe

Plain "make" after the above ./configure doesn't produce anything useful. Will I have to specify the DLL and TLB targets too on the command line? (Apologies, I can't try it out now, msiextract doesn't work for me.)

Quoted 12 lines

Makefile.objs +1 -0

index 286ce06..b6c1505 100644
@@ -102,6 +102,7 @@ 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-prv-obj-y = qga/
 
 vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS)
 

Makefile.objs nested-vars += \ · line 120

Quoted 8 lines

Makefile.objs +1 -0

@@ -113,6 +114,7 @@ nested-vars += \
 	stub-obj-y \
 	util-obj-y \
 	qga-obj-y \
+	qga-prv-obj-y \
 	block-obj-y \
 	common-obj-y
 dummy := $(call unnest-vars)

What does this do? Does "qga-prv-obj-y" stand for "all objects under 'qga'"?

Or does it mean "look into qga/Makefile.objs for further objects"?

Quoted 10 lines

qga/Makefile.objs +0 -0

index b8d7cd0..8d93866 100644
@@ -3,3 +3,9 @@ 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/Makefile.objs qga-obj-$(CONFIG_POSIX) += commands-posix.o channel-posix.o · line 8

Quoted 4 lines

qga-obj-y += qapi-generated/qga-qmp-marshal.o

qga/Makefile.objs +3 -0

+
+ifeq ($(CONFIG_QGA_VSS),y)
+QEMU_CFLAGS += -DHAS_VSS_SDK

Isn't this superfluous? First, I can find no other reference to HAS_VSS_SDK in the series, second, CONFIG_QGA_VSS would be available directly as a macro to source files.

qga/Makefile.objs qga-obj-$(CONFIG_POSIX) += commands-posix.o channel-posix.o · line 11

Quoted 3 lines

qga/Makefile.objs +3 -0

+qga-obj-y += vss-win32-provider/
+qga-prv-obj-y += vss-win32-provider/
+endif

So we're probably just saying "look into vss-win32-provider/Makefile.objs for further object files", for both variables.

Quoted 24 lines

qga/vss-win32-provider/Makefile.objs new file +7 -2

new file mode 100644
index 0000000..1fe1f8f
@@ -0,0 +1,24 @@
+# rules to build qga-provider.dll
+
+qga-obj-y += qga-provider.dll
+qga-prv-obj-y += provider.o install.o
+
+obj-qga-prv-obj-y = $(addprefix $(obj)/, $(qga-prv-obj-y))
+$(obj-qga-prv-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

qga/vss-win32-provider/Makefile.objs new file +3 -2

+
+$(obj)/qga-provider.dll: LDFLAGS = -shared
-Wl,--add-stdcall-alias,--enable-stdcall-fixup -lole32 -loleaut32
-lshlwapi -luuid -static
+$(obj)/qga-provider.dll: $(obj-qga-prv-obj-y)

$(SRC_PATH)/$(obj)/qga-provider.def $(obj)/qga-provider.tlb

qga/vss-win32-provider/Makefile.objs new file +1 -0

+	$(call quiet-command,$(CXX) -o $@ $(qga-prv-obj-y)

Quoted 2 lines

$(SRC_PATH)/qga/vss-win32-provider/qga-provider.def $(CXXFLAGS) $(LDFLAGS)," LINK $(TARGET_DIR)$@")

I'm having a hard time following this.

Looks like "qga-prv-obj-y" consists of nothing more than "provider.o" and "install.o", and that "qga-provider.dll" depends on them. In theory, would it be possible *not* to introduce "qga-prv-obj-y" in the higher-level Makefile.obj files, only here?

Why does "qga-provider.dll" depend on ""qga-provider.tlb"? It is not used in the link command.

Also, why is it necessary to collect the files "provider.o", "install.o" and "qga-provider.def" into a DLL, and link qemu-ga.exe against that DLL (via qga-obj-y)? Is this a VSS requirement? Can't we simply link these objects into qemu-ga.exe statically, like the rest of "qga-obj-y"?

Will some VSS service load the provider DLL independently of qemu-ga.exe?

If so, (a) how will they communicate

(b) shouldn't "qga-obj-y" be independent of "qga-provider.dll"

Could you please draw a dependency graph between these files? Like

idl --> tlb
def --> dll <-- (provider.o, install.o)

Does one of "tlb" and "dll" depend on the other, or are they needed "in parallel"?

... I'll try to continue here. I've peaked forward a little bit, and CQGAVssProvider::CommitSnapshots() seems to be the central method. It kicks the "frozen" event, then blocks until the "thaw" event is kicked back. I wonder how those will translate to QMP communication with libvirt.

Thanks!
Laszlo

Quoted 1 line

Quoted 1 line

(b) shouldn't "qga-obj-y" be independent of "qga-provider.dll"

The DLL is linked to qemu-ga.exe because qemu-ga.exe kicks the registration of the DLL (COMRegister(), which depends on the DLL's Internal variable) at the installation of the qemu-ga service.

Il 25/06/2013 20:23, Tomoki Sekiyama ha scritto:

Quoted 4 lines

Quoted 1 line

Quoted 1 line

(b) shouldn't "qga-obj-y" be independent of "qga-provider.dll"

The DLL is linked to qemu-ga.exe because qemu-ga.exe kicks the registration of the DLL (COMRegister(), which depends on the DLL's Internal variable) at the installation of the qemu-ga service.

Does the DLL also support DllRegisterServer? I don't know Windows very much, but if so I wonder if LoadLibrary/GetProcAddress is preferrable to linking with the DLL.

Paolo

Quoted 6 lines · Laszlo Ersek

qga/Makefile.objs qga-obj-$(CONFIG_POSIX) += commands-posix.o channel-posix.o · line 8

Quoted 2 lines

qga/Makefile.objs +2 -0

+ifeq ($(CONFIG_QGA_VSS),y)
+QEMU_CFLAGS += -DHAS_VSS_SDK

Isn't this superfluous? First, I can find no other reference to HAS_VSS_SDK in the series, second, CONFIG_QGA_VSS would be available directly as a macro to source files.

It is referenced in e.g. qga/commands-win32.c in patch 8/10.

But as you say, I will omit this, by the second reason.

Quoted 2 lines

Will some VSS service load the provider DLL independently of qemu-ga.exe?

Yes, VSS provider DLL is registered to VSS on installation of qemu-ga service (using .TLB), and loaded into VSS service component when snapshot is started.

Quoted 1 line

If so, (a) how will they communicate

Using COM interface.

Quoted 5 lines

... I'll try to continue here. I've peaked forward a little bit, and CQGAVssProvider::CommitSnapshots() seems to be the central method. It kicks the "frozen" event, then blocks until the "thaw" event is kicked back. I wonder how those will translate to QMP communication with libvirt.

CommitSnapshots() is called by VSS, when the requestor of qemu-ga (introduced in next patch) initiates snapshot receiving "guest-fsfreeze-freeze" command.
"frozen" event is used to tell qemu-ga.exe that the fs is frozen, then qemu-ga.exe will tell libvirt to "guest-fsfreeze-freeze" is done.

"thaw" event is kicked by qemnu-ga.exe when it receives "guest-fsfreeze-thaw" command. The command is finished when VSS notify qeum-ga.exe requestor that VSS snapshot process is completed.

On 06/06/13 17:06, Tomoki Sekiyama wrote:

Quoted 41 lines

qga/vss-win32-provider/qga-provider.def new file +10 -0

new file mode 100644
index 0000000..9f3afc8
@@ -0,0 +1,10 @@
+LIBRARY      "QGA-PROVIDER.DLL"
+
+EXPORTS
+	VSSCheckOSVersion	PRIVATE
+	COMRegister		PRIVATE
+	COMUnregister		PRIVATE
+	DllCanUnloadNow		PRIVATE
+	DllGetClassObject	PRIVATE
+	DllRegisterServer	PRIVATE
+	DllUnregisterServer	PRIVATE

qga/vss-win32-provider.h new file +18 -0

new file mode 100644
index 0000000..a437e71
@@ -0,0 +1,26 @@
+/*
+ * QEMU Guest Agent win32 VSS provider declarations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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_PROVIDER_H
+#define VSS_WIN32_PROVIDER_H
+
+#include <windows.h>
+
+STDAPI VSSCheckOSVersion(void);

qga/vss-win32-provider.h line 26

Quoted 8 lines

qga/vss-win32-provider.h new file +8 -0

+
+STDAPI COMRegister(void);
+STDAPI COMUnregister(void);
+
+STDAPI DllRegisterServer(void);
+STDAPI DllUnregisterServer(void);
+
+#endif

Quoted 56 lines

qga/vss-win32.h new file +50 -0

new file mode 100644
index 0000000..21655cf
@@ -0,0 +1,86 @@
+/*
+ * QEMU Guest Agent win32 VSS common declarations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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
+
+/*

qga/vss-win32.h line 58

Quoted 8 lines

qga/vss-win32.h new file +8 -0

+ * 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)

qga/vss-win32.h line 67

Quoted 9 lines

qga/vss-win32.h new file +9 -0

+
+/* 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"

qga/vss-win32.h line 77

Quoted 10 lines

qga/vss-win32.h new file +10 -0

+
+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}");

qga/vss-win32.h line 86

Quoted 11 lines

qga/vss-win32.h new file +9 -0

+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

Quoted 31 lines

qga/vss-win32-provider/install.cpp new file +25 -0

new file mode 100644
index 0000000..d6f1d55
@@ -0,0 +1,493 @@
+/*
+ * QEMU Guest Agent win32 VSS Provider installer
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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 "../vss-win32-provider.h"
+
+#include <comadmin.h>
+#include <wbemidl.h>
+#include <comutil.h>
+
+extern HINSTANCE g_hinstDll;
+

qga/vss-win32-provider/install.cpp line 33

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+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} };

qga/vss-win32-provider/install.cpp line 43

Quoted 10 lines

qga/vss-win32-provider/install.cpp new file +10 -0

+
+static void errmsg(DWORD err, const char *text)
+{
+    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);

qga/vss-win32-provider/install.cpp line 44

Quoted 1 line

qga/vss-win32-provider/install.cpp new file +1 -0

+    printf("%.*s. (Error: %lx) %s\n", len, text, err, msg);

Quoted 5 lines

qga/vss-win32-provider/install.cpp new file +5 -0

+    LocalFree(msg);
+}
+
+static void errmsg_dialog(DWORD err, const char *text, const char *opt = "")
+{

qga/vss-win32-provider/install.cpp line 57

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    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\n", text, opt, err, msg);
+    MessageBox(NULL, buf, "Error from " QGA_PROVIDER_NAME, MB_OK|MB_ICONERROR);

Quoted 26 lines

qga/vss-win32-provider/install.cpp new file +26 -0

+    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)
+
+template<class T>
+HRESULT put_Value(ICatalogObject *pObj, LPCWSTR name, T val)
+{
+    return pObj->put_Value(_bstr_t(name), _variant_t(val));
+}
+
+/* Check whether this OS version supports VSS providers */
+STDAPI VSSCheckOSVersion(void)
+{
+    OSVERSIONINFO OSver;
+
+    OSver.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);

qga/vss-win32-provider/install.cpp line 91

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    GetVersionEx(&OSver);
+    if ((OSver.dwMajorVersion == 5 && OSver.dwMinorVersion >= 2) ||
+       OSver.dwMajorVersion > 5) {
+        return S_OK;
+    }
+    return S_FALSE;
+}
+

qga/vss-win32-provider/install.cpp line 94

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+/* Lookup Administrators group name from winmgmt */
+static HRESULT GetAdminName(_bstr_t &name)
+{

Quoted 12 lines

qga/vss-win32-provider/install.cpp new file +12 -0

+    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));

qga/vss-win32-provider/install.cpp line 114

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    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));

qga/vss-win32-provider/install.cpp line 117

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+    if (!pEnum) {
+        errmsg(E_FAIL, "Failed to query for Administrators");
+        goto out;

qga/vss-win32-provider/install.cpp line 118

Quoted 1 line

qga/vss-win32-provider/install.cpp new file +1 -0

+    }

qga/vss-win32-provider/install.cpp line 126

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    chk(pEnum->Next(WBEM_INFINITE, 1, &pWobj, &returned));
+    if (returned == 0) {
+        errmsg(E_FAIL, "Failed to query for Administrators");
+        goto out;
+    }
+
+    chk(pWobj->Get(_bstr_t(L"Name"), 0, &var, 0, 0));
+    name = var;

Quoted 7 lines

qga/vss-win32-provider/install.cpp new file +7 -0

+out:
+    if (pLoc) {
+        pLoc->Release();
+    }
+    if (pSvc) {
+        pSvc->Release();
+    }

qga/vss-win32-provider/install.cpp line 141

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    if (pEnum) {
+        pEnum->Release();
+    }
+    if (pWobj) {
+        pWobj->Release();
+    }
+    return hr;
+}

Quoted 9 lines

qga/vss-win32-provider/install.cpp new file +9 -0

+
+/* 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;

qga/vss-win32-provider/install.cpp line 158

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    long n;
+    _bstr_t name;
+    _variant_t key;
+    CHAR dllPath[MAX_PATH], tlbPath[MAX_PATH];
+
+    if (!g_hinstDll) {
+        errmsg(E_FAIL, "Failed to initialize DLL");
+        goto out;

qga/vss-win32-provider/install.cpp line 162

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+    }
+
+    if (VSSCheckOSVersion() == S_FALSE) {
+        printf("VSS provider is not supported in this OS version.\n");

qga/vss-win32-provider/install.cpp line 163

Quoted 1 line

qga/vss-win32-provider/install.cpp new file +1 -0

+        return S_FALSE; /* VSS feature is disabled */

qga/vss-win32-provider/install.cpp line 166

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+    }
+
+    COMUnregister();

COMRegister and COMUnregister are called byqemu-ga -s install, to register/unregister the DLL into/from COM+ application catalogue.

qga/vss-win32-provider/install.cpp line 168

Quoted 2 lines

qga/vss-win32-provider/install.cpp new file +2 -0

+
+    chk(CoInitialize(NULL));

Quoted 9 lines

qga/vss-win32-provider/install.cpp new file +9 -0

+    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());

qga/vss-win32-provider/install.cpp line 185

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    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));

qga/vss-win32-provider/install.cpp line 189

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+    chk(pObj->get_Key(&key));
+
+    pObj->Release();
+    pObj = NULL;

qga/vss-win32-provider/install.cpp line 193

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+
+    if (!GetModuleFileName(g_hinstDll, dllPath, sizeof(dllPath))) {
+        errmsg(GetLastError(), "GetModuleFileName failed");
+        goto out;

qga/vss-win32-provider/install.cpp line 197

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+    }
+    n = strlen(dllPath);
+    if (n < 3) {
+        errmsg(E_FAIL, "Failed to lookup dll");

qga/vss-win32-provider/install.cpp line 203

Quoted 6 lines

qga/vss-win32-provider/install.cpp new file +6 -0

+    }
+    strcpy(tlbPath, dllPath);
+    strcpy(tlbPath+n-3, "TLB");
+    printf("Registering " QGA_PROVIDER_NAME ":\n");
+    printf("  %s\n", dllPath);
+    printf("  %s\n", tlbPath);

qga/vss-win32-provider/install.cpp line 206

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+    if (!PathFileExists(tlbPath)) {
+        errmsg(ERROR_FILE_NOT_FOUND, "Failed to lookup tlb");
+        goto out;

Quoted 51 lines

qga/vss-win32-provider/install.cpp new file +51 -0

+    }
+
+    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) {

qga/vss-win32-provider/install.cpp line 265

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+        pUsersInRole->Release();
+    }
+    if (pObj) {
+        pObj->Release();
+    }
+
+    if (FAILED(hr)) {
+        COMUnregister();

qga/vss-win32-provider/install.cpp line 267

Quoted 2 lines

qga/vss-win32-provider/install.cpp new file +2 -0

+    }
+    CoUninitialize();

Quoted 9 lines

qga/vss-win32-provider/install.cpp new file +9 -0

+
+    return hr;
+}
+
+/* Unregister this module from COM+ Applications Catalog */
+STDAPI COMUnregister(void)
+{
+    HRESULT hr;
+    IUnknown *pUnknown = NULL;

qga/vss-win32-provider/install.cpp line 284

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    ICOMAdminCatalog *pCatalog = NULL;
+    ICatalogCollection *pColl = NULL;
+    ICatalogObject *pObj = NULL;
+    _variant_t var;
+    long i, n;
+
+    if (VSSCheckOSVersion() == S_FALSE) {
+        printf("VSS provider is not supported in this OS version.\n");

qga/vss-win32-provider/install.cpp line 288

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+        return S_FALSE; /* VSS feature is disabled */
+    }
+
+    chk(DllUnregisterServer());

qga/vss-win32-provider/install.cpp line 290

Quoted 2 lines

qga/vss-win32-provider/install.cpp new file +2 -0

+
+    chk(CoInitialize(NULL));

Quoted 689 lines

qga/vss-win32-provider/install.cpp new file +203 -0

+    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)) {
+            printf("Removing COM+ Application: %S\n", (wchar_t *)_bstr_t(var));
+            chk(pColl->Remove(i));
+        }
+    }
+    chk(pColl->SaveChanges(&n));
+
+out:
+    if (pUnknown) {
+        pUnknown->Release();
+    }
+    if (pCatalog) {
+        pCatalog->Release();
+    }
+    if (pColl) {
+        pColl->Release();
+    }
+    if (pObj) {
+        pObj->Release();
+    }
+    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 = (lstrlen(data) + 1) * sizeof(TCHAR);
+    } 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;
+    }
+
+    sprintf(key, "CLSID\\%s\\InprocServer32", g_szClsid);
+    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");
+        goto out;
+    }
+
+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 functions for _bstr_t in MinGW: Originally written by: Diaa Sami */
+
+void __stdcall _com_issue_error(HRESULT hr)
+{
+    printf("_com_issue_error() called with parameter HRESULT = %lu", hr);
+}
+
+namespace _com_util
+{
+    char * __stdcall ConvertBSTRToString(BSTR bstr)
+    {
+        const unsigned int stringLength = lstrlenW(bstr);
+        char *const ascii = new char [stringLength + 1];
+
+        wcstombs(ascii, bstr, stringLength + 1);
+
+        return ascii;
+    }
+
+    BSTR __stdcall ConvertStringToBSTR(const char *const ascii)
+    {
+        const unsigned int stringLength = lstrlenA(ascii);
+        BSTR bstr = SysAllocStringLen(NULL, stringLength);
+
+        mbstowcs(bstr, ascii, stringLength + 1);
+
+        return bstr;
+    }
+}

qga/vss-win32-provider/provider.cpp new file +479 -0

new file mode 100644
index 0000000..90a3d25
@@ -0,0 +1,479 @@
+/*
+ * QEMU Guest Agent win32 VSS Provider implementations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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"
+
+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 block)
+{
+    if (block) {
+        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;
+    } else if (riid == IID_IVssSoftwareSnapshotProvider) {
+        *ppObj = static_cast<void*>(
+            static_cast<IVssSoftwareSnapshotProvider*>(this));
+        AddRef();
+        return S_OK;
+    } else if (riid == IID_IVssProviderCreateSnapshotSet) {
+        *ppObj = static_cast<void*>(
+            static_cast<IVssProviderCreateSnapshotSet*>(this));
+        AddRef();
+        return S_OK;
+    } else 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)
+{
+    *ppEnum = new CQGAVSSEnumObject;
+    (*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)
+{
+    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 S_OK;
+}
+
+
+/*
+ * 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 hEvent, hEvent2;
+
+    hEvent = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_FROZEN);
+    if (hEvent == INVALID_HANDLE_VALUE) {
+        hr = E_FAIL;
+        goto out;
+    }
+
+    hEvent2 = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_THAW);
+    if (hEvent == INVALID_HANDLE_VALUE) {
+        CloseHandle(hEvent);
+        hr = E_FAIL;
+        goto out;
+    }
+
+    SetEvent(hEvent);
+    if (WaitForSingleObject(hEvent2, 60*1000) != WAIT_OBJECT_0) {
+        hr = E_ABORT;
+    }
+
+    CloseHandle(hEvent2);
+    CloseHandle(hEvent);
+out:
+    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 bLock) { return E_NOTIMPL; }
+private:
+    long m_nRefCount;
+};
+
+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()
+{
+    LockModule(TRUE);
+    return 2;
+}
+
+STDMETHODIMP_(ULONG) CQGAVssProviderFactory::Release()
+{
+    LockModule(FALSE);
+    return 1;
+}
+
+STDMETHODIMP CQGAVssProviderFactory::CreateInstance(
+    IUnknown *pUnknownOuter, REFIID iid, void **ppv)
+{
+    if (pUnknownOuter) {
+        return CLASS_E_NOAGGREGATION;
+    }
+    CQGAVssProvider *pObj = new CQGAVssProvider;
+    if (!pObj) {
+        return E_OUTOFMEMORY;
+    }
+    return pObj->QueryInterface(iid, ppv);
+}
+
+
+/*
+ * DLL functions
+ */
+
+STDAPI DllGetClassObject(REFCLSID rclsid, REFIID riid, LPVOID *ppv)
+{
+    static CQGAVssProviderFactory factory;
+
+    *ppv = NULL;
+    if (IsEqualCLSID(rclsid, CLSID_QGAVSSProvider)) {
+        return factory.QueryInterface(riid, ppv);
+    }
+    return CLASS_E_CLASSNOTAVAILABLE;
+}
+
+STDAPI DllCanUnloadNow()
+{
+    return g_nComObjsInUse == 0 ? S_OK : S_FALSE;
+}
+
+EXTERN_C
+BOOL WINAPI DllMain(HINSTANCE hinstDll, DWORD dwReason, LPVOID lpReserved)
+{
+    switch (dwReason) {
+
+    case DLL_PROCESS_ATTACH:
+        g_hinstDll = hinstDll;
+        DisableThreadLibraryCalls(hinstDll);
+        break;
+    }
+
+    return TRUE;
+}

Quoted 2 lines

Quoted 2 lines

Quoted 2 lines

qga/vss-win32.h line 67

Quoted 2 lines

qga/vss-win32.h new file +2 -0

+#define EVENT_NAME_FROZEN "Global\\QGAVSSEvent-frozen"
+#define EVENT_NAME_THAW   "Global\\QGAVSSEvent-thaw"

No idea what I'm talking about, but since we're qualifying the second component with the "QGAVSSEvent" prefix, shouldn't we just replace the first component ("Global") with it? Or would it effect "event routing"?

Quoted 1 line · Laszlo Ersek

On 06/06/13 17:06, Tomoki Sekiyama wrote:

Comparing the .def file and the provider header file:
...
(a) what is the reason for not listing DllCanUnloadNow() and DllGetClassObject() in the header file?

(b) Does STDAPI imply a return type? Or are you just going with the implicit "int"? (Based on my encounters with EFIAPI, I think it's the latter.)

Quoted 2 lines

qga/vss-win32.h line 67

Quoted 2 lines

qga/vss-win32.h new file +2 -0

+#define EVENT_NAME_FROZEN "Global\\QGAVSSEvent-frozen"
+#define EVENT_NAME_THAW   "Global\\QGAVSSEvent-thaw"

No idea what I'm talking about, but since we're qualifying the second component with the "QGAVSSEvent" prefix, shouldn't we just replace the first component ("Global") with it? Or would it effect "event routing"? (Tangential question, anyway.)

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 33

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+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} };

Would it be possible to make these static? Not too important of course.

Quoted 8 lines

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+
+static void errmsg(DWORD err, const char *text)
+{
+    char *msg = NULL, *nul = strchr(text, '(');
+    int len = nul ? nul - text : -1;
+
+    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+                  FORMAT_MESSAGE_FROM_SYSTEM |

Quoted 4 lines

Quoted 4 lines

FORMAT_MESSAGE_IGNORE_INSERTS,
+ NULL, err, MAKELANGID(LANG_NEUTRAL,
SUBLANG_DEFAULT),
+ (char *)&msg, 0, NULL);

(The FormatMessage() specification in MSDN is simply incredible. "(char *)&msg", seriously? Your code is correct, but the interface is unbelievable.)

Quoted 1 line

Quoted 1 line

+ printf("%.*s. (Error: %lx) %s\n", len, text, err, msg);

(a) Since we're printing an error message here, I suspect it should go to stderr.

(b) In case "text" doesn't contain an opening paren, "len" is set to -1. "A negative precision is taken as if the precision were omitted", IOW the entire string will be printed. Clever!

(c) Does DWORD expand to "uint32_t"? In that case "%lx" is too big on 64-bit (LP64). We should probably use "%x" or "%"PRIx32. (Or do we build qemu-ga.exe only for 32-bit? I seem to remember something like that.)

Quoted 4 lines

Quoted 4 lines

+ snprintf(buf, sizeof(buf), "%s%s. (Error: %lx) %s\n", text, opt,
err, msg);
+ MessageBox(NULL, buf, "Error from " QGA_PROVIDER_NAME,
MB_OK|MB_ICONERROR);

Do you need a trailing newline for a message box?

Quoted 3 lines

qga/vss-win32-provider/install.cpp line 94

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+/* Lookup Administrators group name from winmgmt */
+static HRESULT GetAdminName(_bstr_t &name)
+{

I can see that you want to call GetAdminName() in chk(), hence you must return a HRESULT and store the value through the parameter list. However, can we keep the C++ features to a minimum? I'd prefer if the non-const reference were replaced with a pointer-to-_bstr_t. (Tangential, change only if you respin anyway and don't mind it.)

Quoted 3 lines

qga/vss-win32-provider/install.cpp line 117

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+    if (!pEnum) {
+        errmsg(E_FAIL, "Failed to query for Administrators");
+        goto out;

I think you forgot to set "hr" to something ugly -- the code below the "out" label will simply return it, and "hr" is currently something nice. (The last chk() succeeded.)

Quoted 1 line

Quoted 1 line

+ }

This branch is probably for the case when ExecQuery() succeeds, but doesn't return any rows, right?

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 126

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    chk(pEnum->Next(WBEM_INFINITE, 1, &pWobj, &returned));
+    if (returned == 0) {
+        errmsg(E_FAIL, "Failed to query for Administrators");
+        goto out;
+    }
+
+    chk(pWobj->Get(_bstr_t(L"Name"), 0, &var, 0, 0));
+    name = var;

This assigns a _variant_t to a _bstr_t (... for which I proposed *name = var above, but it's irrelevant now).

Can this conversion (or the assignment operator) fail? If so, does either throw an exception?

Quoted 7 lines

Quoted 7 lines

qga/vss-win32-provider/install.cpp new file +7 -0

+out:
+    if (pLoc) {
+        pLoc->Release();
+    }
+    if (pSvc) {
+        pSvc->Release();
+    }

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 141

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    if (pEnum) {
+        pEnum->Release();
+    }
+    if (pWobj) {
+        pWobj->Release();
+    }
+    return hr;
+}

I'm sure this is idiomatic code, but do these pointers point to static / long-term instances? I'm missing the equivalent of "delete pLoc" and so on. Each Release() member function gets the implicit "this" parameter here, but do they free it too? (Honestly, I can't decide which would be worse, if they did or they didn't.)

... Ah, it's probably reference counting. OK.

Quoted 3 lines

qga/vss-win32-provider/install.cpp line 158

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+    if (!g_hinstDll) {
+        errmsg(E_FAIL, "Failed to initialize DLL");
+        goto out;

OK, "hr" is E_FAIL here.

Quoted 4 lines

qga/vss-win32-provider/install.cpp line 162

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+    }
+
+    if (VSSCheckOSVersion() == S_FALSE) {
+        printf("VSS provider is not supported in this OS version.\n");

I suggest stderr.

Quoted 1 line

Quoted 1 line

+ return S_FALSE; /* VSS feature is disabled */

Somewhat inconsistent with the above, you issue "return" although you used "goto out" before. No resources are leaked so it's no problem in practice. (You could have written "return" above.)

Quoted 3 lines

qga/vss-win32-provider/install.cpp line 166

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+    }
+
+    COMUnregister();

What requires / justifies this? (I can see another call below, on the error path.) I think whatever COMUnregister() would release depends first on the success of COMRegister(), doesn't it?

You've told Paolo,

Quoted 2 lines · Tomoki Sekiyama

COMRegister and COMUnregister are called byqemu-ga -s install, to register/unregister the DLL into/from COM+ application catalogue.

and indeed I can see a COMRegister() call in 09/10. Nonetheless that doesn't seem to justify this call to COMUnregister() -- if the DLL has been previously registered in the application catalog, a new registration attempt should fail.

Quoted 2 lines

Review

Quoted 2 lines

(quoted diff) +2 -0

+
+    chk(CoInitialize(NULL));

Can this fail in practice? If so, we could have error handling trouble, because "out:" will call CoUninitialize() without any successful initialization.

Quoted 5 lines

Quoted 5 lines

qga/vss-win32-provider/install.cpp new file +5 -0

+    /* Install COM+ Component */
+
+    chk(pCatalog->GetCollection(_bstr_t(L"Applications"),
+                                (IDispatch **)&pApps));
+    chk(pApps->Populate());

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 185

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    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));

This looks like a globally visible change that is not rolled back if something fails later in this function. Is the COMUnregister() call on the error handling path supposed to undo these? Complicated :)

Then, should we check "n", or does the retval check suffice?

Quoted 4 lines

qga/vss-win32-provider/install.cpp line 193

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+
+    if (!GetModuleFileName(g_hinstDll, dllPath, sizeof(dllPath))) {
+        errmsg(GetLastError(), "GetModuleFileName failed");
+        goto out;

"hr" has not been set to a failure code.

Quoted 4 lines

qga/vss-win32-provider/install.cpp line 197

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+    }
+    n = strlen(dllPath);
+    if (n < 3) {
+        errmsg(E_FAIL, "Failed to lookup dll");

Presumably you wanted to set "hr" and jump to "out" as well.

Quoted 6 lines

qga/vss-win32-provider/install.cpp line 203

Quoted 6 lines

qga/vss-win32-provider/install.cpp new file +6 -0

+    }
+    strcpy(tlbPath, dllPath);
+    strcpy(tlbPath+n-3, "TLB");
+    printf("Registering " QGA_PROVIDER_NAME ":\n");
+    printf("  %s\n", dllPath);
+    printf("  %s\n", tlbPath);

These are arguably diagnostic messages (destined for stderr), but I won't press it :)

Quoted 3 lines

qga/vss-win32-provider/install.cpp line 206

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+    if (!PathFileExists(tlbPath)) {
+        errmsg(ERROR_FILE_NOT_FOUND, "Failed to lookup tlb");
+        goto out;

"hr" not set properly.

Quoted 1 line

Quoted 1 line

+ CoUninitialize();

Another question: can you nest CoInitialize() calls (and more importantly, does CoUninitialize() respect that)? Consider the following call chain:

COMRegister()
CoInitialize()
COMUnregister() -- on the "out:" path
DllUnregisterServer()
CoInitialize() -- init after init CoUninitialize()
CoInitialize()
CoUninitialize()
CoUninitialize() -- right here, uninit after uninit

Will these work (especially the final two)?

Quoted 7 lines

Quoted 7 lines

qga/vss-win32-provider/install.cpp new file +7 -0

+/* Unregister this module from COM+ Applications Catalog */
+STDAPI COMUnregister(void)
+{
+    HRESULT hr;
+    IUnknown *pUnknown = NULL;
+    ICOMAdminCatalog *pCatalog = NULL;
+    ICatalogCollection *pColl = NULL;

Quoted 6 lines

qga/vss-win32-provider/install.cpp line 284

Quoted 6 lines

qga/vss-win32-provider/install.cpp new file +6 -0

+    ICatalogObject *pObj = NULL;
+    _variant_t var;
+    long i, n;
+
+    if (VSSCheckOSVersion() == S_FALSE) {
+        printf("VSS provider is not supported in this OS version.\n");

I suggest stderr again.

Quoted 4 lines

qga/vss-win32-provider/install.cpp line 288

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+        return S_FALSE; /* VSS feature is disabled */
+    }
+
+    chk(DllUnregisterServer());

Apparently DllUnregisterServer() can't fail. (And it shouldn't, we depend on it, since COMUnregister() is also used as destructor after partial construction, so we must not bail here.) I propose to change the return type of DllUnregisterServer() to void, just to drive the point home.

Quoted 2 lines

Review

Quoted 2 lines

(quoted diff) +2 -0

+
+    chk(CoInitialize(NULL));

(same question as before -- can this fail? See unconditional uninit at the bottom.)

I'll continue from here.

Quoted 13 lines · Laszlo Ersek

Quoted 11 lines · Tomoki Sekiyama

qga/vss-win32-provider/install.cpp new file +11 -0

+/* 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;
+

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 290

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    if (VSSCheckOSVersion() == S_FALSE) {
+        printf("VSS provider is not supported in this OS version.\n");
+        return S_FALSE; /* VSS feature is disabled */
+    }
+
+    chk(DllUnregisterServer());
+
+    chk(CoInitialize(NULL));

Quoted 6 lines

Quoted 6 lines

qga/vss-win32-provider/install.cpp new file +6 -0

+    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));

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 304

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    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)) {
+            printf("Removing COM+ Application: %S\n", (wchar_t *)_bstr_t(var));

Quoted 2 lines

Review

Quoted 2 lines

(quoted diff) +2 -0

+            chk(pColl->Remove(i));
+        }

Quoted 2 lines

Review

Quoted 2 lines

(quoted diff) +2 -0

+    }
+    chk(pColl->SaveChanges(&n));

Quoted 26 lines

Quoted 26 lines

qga/vss-win32-provider/install.cpp new file +26 -0

+
+out:
+    if (pUnknown) {
+        pUnknown->Release();
+    }
+    if (pCatalog) {
+        pCatalog->Release();
+    }
+    if (pColl) {
+        pColl->Release();
+    }
+    if (pObj) {
+        pObj->Release();
+    }
+    CoUninitialize();
+
+    return hr;
+}
+
+
+static BOOL CreateRegistryKey(LPCTSTR key, LPCTSTR value, LPCTSTR data)
+{
+    HKEY  hKey;
+    LONG  ret;
+    DWORD size;
+

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 342

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    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 = (lstrlen(data) + 1) * sizeof(TCHAR);

Quoted 11 lines

qga/vss-win32-provider/install.cpp line 353

Quoted 11 lines

qga/vss-win32-provider/install.cpp new file +11 -0

+    } 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);

Quoted 29 lines

Quoted 29 lines

qga/vss-win32-provider/install.cpp new file +29 -0

+        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");

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 390

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+        goto out;
+    }
+    sprintf(key, "CLSID\\%s\\InprocServer32", g_szClsid);
+    if (!CreateRegistryKey(key, NULL, dllPath)) {
+        goto out;
+    }
+
+    sprintf(key, "CLSID\\%s\\InprocServer32", g_szClsid);

Quoted 12 lines

Quoted 12 lines

qga/vss-win32-provider/install.cpp new file +12 -0

+    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;
+    }

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 410

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+
+    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);

Quoted 9 lines

qga/vss-win32-provider/install.cpp line 419

Quoted 9 lines

qga/vss-win32-provider/install.cpp new file +9 -0

+    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);

Quoted 3 lines

qga/vss-win32-provider/install.cpp line 422

Quoted 3 lines

qga/vss-win32-provider/install.cpp new file +3 -0

+    if (FAILED(hr)) {
+        errmsg_dialog(hr, "RegisterProvider failed");
+        goto out;

Quoted 17 lines

Quoted 17 lines

qga/vss-win32-provider/install.cpp new file +17 -0

+    }
+
+out:
+    if (pVssAdmin) {
+        pVssAdmin->Release();
+    }
+    CoUninitialize();
+
+    if (FAILED(hr)) {
+        DllUnregisterServer();
+    }
+
+    return hr;
+}
+
+/* Unregister this VSS hardware provider from the system */
+STDAPI DllUnregisterServer(void)

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 447

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+{
+    TCHAR key[256];
+    IVssAdmin *pVssAdmin = NULL;
+
+    CoInitialize(NULL);
+
+    HRESULT hr = CoCreateInstance(CLSID_VSSCoordinator,
+         NULL, CLSCTX_ALL, IID_IVssAdmin, (void **)&pVssAdmin);

Quoted 7 lines

Quoted 7 lines

qga/vss-win32-provider/install.cpp new file +7 -0

+    if (SUCCEEDED(hr)) {
+        hr = pVssAdmin->UnregisterProvider(g_gProviderId);
+        pVssAdmin->Release();
+    } else {
+        errmsg_dialog(hr, "CoCreateInstance(VSSCoordinator) failed");
+    }
+

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 462

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    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 */
+}

Quoted 4 lines

qga/vss-win32-provider/install.cpp line 466

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+
+
+/* Support functions for _bstr_t in MinGW: Originally written by: Diaa Sami */
+

Quoted 4 lines

qga/vss-win32-provider/install.cpp line 470

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+void __stdcall _com_issue_error(HRESULT hr)
+{
+    printf("_com_issue_error() called with parameter HRESULT = %lu", hr);
+}

Quoted 4 lines

Quoted 4 lines

qga/vss-win32-provider/install.cpp new file +4 -0

+
+namespace _com_util
+{
+    char * __stdcall ConvertBSTRToString(BSTR bstr)

Quoted 8 lines

qga/vss-win32-provider/install.cpp line 482

Quoted 8 lines

qga/vss-win32-provider/install.cpp new file +8 -0

+    {
+        const unsigned int stringLength = lstrlenW(bstr);
+        char *const ascii = new char [stringLength + 1];
+
+        wcstombs(ascii, bstr, stringLength + 1);
+
+        return ascii;
+    }

Quoted 52 lines

Quoted 52 lines

qga/vss-win32-provider/install.cpp new file +11 -0

+
+    BSTR __stdcall ConvertStringToBSTR(const char *const ascii)
+    {
+        const unsigned int stringLength = lstrlenA(ascii);
+        BSTR bstr = SysAllocStringLen(NULL, stringLength);
+
+        mbstowcs(bstr, ascii, stringLength + 1);
+
+        return bstr;
+    }
+}

qga/vss-win32-provider/provider.cpp new file +33 -0

new file mode 100644
index 0000000..90a3d25
@@ -0,0 +1,479 @@
+/*
+ * QEMU Guest Agent win32 VSS Provider implementations
+ *
+ * Copyright Hitachi Data Systems Corp. 2013
+ *
+ * Authors:
+ *  Tomoki Sekiyama   <[email protected]>
+ *
+ * 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"
+
+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} };