[Qemu-devel] [PATCH 0/2 v7] Add Windows support for time resync by qemu-ga

[Qemu-devel] [PATCH 0/2 v7] Add Windows support for time resync by qemu-ga

[Lei Li]

This patch series attempts to add Windows implementation
for qemu-ga commands guest-get-time and guest-set-time.

The previous thread about the interfaces introduced and 
the POSIX-specific command implementation has already
been accepted, the reference link:

http://article.gmane.org/gmane.comp.emulators.qemu/198472

Notes:
Now It was tested on Windows XP SP3 and Windows 7.
Please comment!

Thanks.

Changes since v6:
  - Fix other error handel that I missed.

Changes since v5:
  - Fix the error check for GetSystemTime() from Michael.
  - Other fixups from Michael.

Changes since v4:
  - Error handel improvement from Michael.
  - Do the math explicitly for the time convert of FILETIME
    suggested by Michael.

Changes since v3:
  - Reorder the acquire_privilege to avoid a possible
    leak of privileges suggested by Eric.

Changes since v2:
  - Overflow check improvement for time_ns from Eric.

Changes since v1:
  - Make the macro for the offset between windows baseline
    and Unix Epoch more readable from Eric.
  - Overflow check for filetime pointed by Eric.

Lei Li (2):
    qga: add windows implementation for guest-get-time
    qga: add windows implementation for guest-set-time

[Qemu-devel] [PATCH 1/2] qga: add windows implementation for guest-get-time

[Lei Li]

Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
---
 qga/commands-win32.c | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/qga/commands-win32.c b/qga/commands-win32.c
index b19be9d..d98e3ee 100644
--- a/qga/commands-win32.c
+++ b/qga/commands-win32.c
@@ -22,6 +22,12 @@
 #define SHTDN_REASON_FLAG_PLANNED 0x80000000
 #endif
 
+/* multiple of 100 nanoseconds elapsed between windows baseline
+ *    (1/1/1601) and Unix Epoch (1/1/1970), accounting for leap years */
+#define W32_FT_OFFSET (10000000ULL * 60 * 60 * 24 * \
+                       (365 * (1970 - 1601) +       \
+                        (1970 - 1601) / 4 - 3))
+
 static void acquire_privilege(const char *name, Error **err)
 {
     HANDLE token;
@@ -280,8 +286,25 @@ GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **err)
 
 int64_t qmp_guest_get_time(Error **errp)
 {
-    error_set(errp, QERR_UNSUPPORTED);
-    return -1;
+    SYSTEMTIME ts = {0};
+    int64_t time_ns;
+    FILETIME tf;
+
+    GetSystemTime(&ts);
+    if (ts.wYear < 1601 || ts.wYear > 30827) {
+        error_setg(errp, "Failed to get time");
+        return -1;
+    }
+
+    if (!SystemTimeToFileTime(&ts, &tf)) {
+        error_setg(errp, "Failed to convert system time: %d", (int)GetLastError());
+        return -1;
+    }
+
+    time_ns = ((((int64_t)tf.dwHighDateTime << 32) | tf.dwLowDateTime)
+                - W32_FT_OFFSET) * 100;
+
+    return time_ns;
 }
 
 void qmp_guest_set_time(int64_t time_ns, Error **errp)
-- 
1.7.11.7

[Qemu-devel] [PATCH 2/2] qga: add windows implementation for guest-set-time

[Lei Li]

Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
---
 qga/commands-win32.c | 29 ++++++++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/qga/commands-win32.c b/qga/commands-win32.c
index d98e3ee..24e4ad0 100644
--- a/qga/commands-win32.c
+++ b/qga/commands-win32.c
@@ -309,7 +309,34 @@ int64_t qmp_guest_get_time(Error **errp)
 
 void qmp_guest_set_time(int64_t time_ns, Error **errp)
 {
-    error_set(errp, QERR_UNSUPPORTED);
+    SYSTEMTIME ts;
+    FILETIME tf;
+    LONGLONG time;
+
+    if (time_ns < 0 || time_ns / 100 > INT64_MAX - W32_FT_OFFSET) {
+        error_setg(errp, "Time %" PRId64 "is invalid", time_ns);
+        return;
+    }
+
+    time = time_ns / 100 + W32_FT_OFFSET;
+
+    tf.dwLowDateTime = (DWORD) time;
+    tf.dwHighDateTime = (DWORD) (time >> 32);
+
+    if (!FileTimeToSystemTime(&tf, &ts)) {
+        error_setg(errp, "Failed to convert system time %d", (int)GetLastError());
+        return;
+    }
+
+    acquire_privilege(SE_SYSTEMTIME_NAME, errp);
+    if (error_is_set(errp)) {
+        return;
+    }
+
+    if (!SetSystemTime(&ts)) {
+        error_setg(errp, "Failed to set time to guest: %d", (int)GetLastError());
+        return;
+    }
 }
 
 GuestLogicalProcessorList *qmp_guest_get_vcpus(Error **errp)
-- 
1.7.11.7

Re: [Qemu-devel] [PATCH 0/2 v7] Add Windows support for time resync by qemu-ga

[Eric Blake]

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On 03/15/2013 03:29 AM, Lei Li wrote:
> This patch series attempts to add Windows implementation
> for qemu-ga commands guest-get-time and guest-set-time.
> 
> The previous thread about the interfaces introduced and 
> the POSIX-specific command implementation has already
> been accepted, the reference link:
> 
> http://article.gmane.org/gmane.comp.emulators.qemu/198472
> 
> Notes:
> Now It was tested on Windows XP SP3 and Windows 7.
> Please comment!

Series: Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


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Re: [Qemu-devel] [PATCH 0/2 v7] Add Windows support for time resync by qemu-ga

[mdroth]

On Fri, Mar 15, 2013 at 05:29:03PM +0800, Lei Li wrote:
> This patch series attempts to add Windows implementation
> for qemu-ga commands guest-get-time and guest-set-time.

Thanks, applied to qga branch.

> 
> The previous thread about the interfaces introduced and 
> the POSIX-specific command implementation has already
> been accepted, the reference link:
> 
> http://article.gmane.org/gmane.comp.emulators.qemu/198472
> 
> Notes:
> Now It was tested on Windows XP SP3 and Windows 7.
> Please comment!
> 
> Thanks.
> 
> Changes since v6:
>   - Fix other error handel that I missed.
> 
> Changes since v5:
>   - Fix the error check for GetSystemTime() from Michael.
>   - Other fixups from Michael.
> 
> Changes since v4:
>   - Error handel improvement from Michael.
>   - Do the math explicitly for the time convert of FILETIME
>     suggested by Michael.
> 
> Changes since v3:
>   - Reorder the acquire_privilege to avoid a possible
>     leak of privileges suggested by Eric.
> 
> Changes since v2:
>   - Overflow check improvement for time_ns from Eric.
> 
> Changes since v1:
>   - Make the macro for the offset between windows baseline
>     and Unix Epoch more readable from Eric.
>   - Overflow check for filetime pointed by Eric.
> 
> Lei Li (2):
>     qga: add windows implementation for guest-get-time
>     qga: add windows implementation for guest-set-time
>