Re: [PATCH 2/5] util/oslib-win32: Add a helper to get the Windows version

[Yan Vugenfirer]

On Wed, Jul 27, 2022 at 10:43 AM Bin Meng <bmeng.cn@gmail.com> wrote:
>
> From: Bin Meng <bin.meng@windriver.com>
>
> This adds a helper to get the Windows version via the RtlGetVersion
> call, for QEMU codes to determine the Windows version at run-time.
>
> Signed-off-by: Xuzhou Cheng <xuzhou.cheng@windriver.com>
> Signed-off-by: Bin Meng <bin.meng@windriver.com>
> ---
>
>  include/sysemu/os-win32.h |  2 ++
>  util/oslib-win32.c        | 15 +++++++++++++++
>  2 files changed, 17 insertions(+)
>
> diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
> index edc3b38a57..1e324026a4 100644
> --- a/include/sysemu/os-win32.h
> +++ b/include/sysemu/os-win32.h
> @@ -204,6 +204,8 @@ ssize_t qemu_recv_wrap(int sockfd, void *buf, size_t len, 
> int flags);
>  ssize_t qemu_recvfrom_wrap(int sockfd, void *buf, size_t len, int flags,
>                             struct sockaddr *addr, socklen_t *addrlen);
>
> +void os_get_win_version(RTL_OSVERSIONINFOEXW *info);
> +
>  #ifdef __cplusplus
>  }
>  #endif
> diff --git a/util/oslib-win32.c b/util/oslib-win32.c
> index 5723d3eb4c..6d2387b9ff 100644
> --- a/util/oslib-win32.c
> +++ b/util/oslib-win32.c
> @@ -547,3 +547,18 @@ int qemu_msync(void *addr, size_t length, int fd)
>       */
>      return qemu_fdatasync(fd);
>  }
> +
> +void os_get_win_version(RTL_OSVERSIONINFOEXW *info)
> +{
> +    typedef LONG (WINAPI *rtl_get_version_t)(PRTL_OSVERSIONINFOEXW);
> +
> +    /* RtlGetVersion is available starting with Windows 2000 */
> +    HMODULE module = GetModuleHandle("ntdll");
> +    PVOID fun = GetProcAddress(module, "RtlGetVersion");
> +    rtl_get_version_t rtl_get_version = (rtl_get_version_t)fun;
> +
> +    info->dwOSVersionInfoSize = sizeof(RTL_OSVERSIONINFOEXW);
> +    rtl_get_version(info);
The original function, when it was present in qemu-ga, tested that
getting the function address succeeded.
I think this test should be kept.
See below:
-    PVOID fun = GetProcAddress(module, "RtlGetVersion");
-    if (fun == NULL) {
-        error_setg(errp, QERR_QGA_COMMAND_FAILED,
-            "Failed to get address of RtlGetVersion");
-        return;
-    }

Best regards,
Yan.
> +
> +    return;
> +}
> --
> 2.34.1
>
>