diff mbox series

[09/24] golang/xenlight: define MsVmGenid builtin type

Message ID 87f082bdf06e820e911256138a7380d0cf7019a2.1570456846.git.rosbrookn@ainfosec.com (mailing list archive)
State Superseded
Headers show
Series generated Go libxl bindings using IDL | expand

Commit Message

Nick Rosbrook Oct. 7, 2019, 3:12 p.m. UTC
From: Nick Rosbrook <rosbrookn@ainfosec.com>

Define MsVmGenid as [int(C.LIBXL_MS_VM_GENID_LEN)]byte and implement fromC and toC functions.

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
---
Cc: George Dunlap <george.dunlap@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Wei Liu <wl@xen.org>

 tools/golang/xenlight/xenlight.go | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

Comments

George Dunlap Nov. 13, 2019, 4:20 p.m. UTC | #1
On 10/7/19 4:12 PM, Nick Rosbrook wrote:
> From: Nick Rosbrook <rosbrookn@ainfosec.com>
> 
> Define MsVmGenid as [int(C.LIBXL_MS_VM_GENID_LEN)]byte and implement fromC and toC functions.
> 
> Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
> ---
> Cc: George Dunlap <george.dunlap@citrix.com>
> Cc: Ian Jackson <ian.jackson@eu.citrix.com>
> Cc: Wei Liu <wl@xen.org>
> 
>  tools/golang/xenlight/xenlight.go | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/tools/golang/xenlight/xenlight.go b/tools/golang/xenlight/xenlight.go
> index 3b7824b284..6aca5b89c0 100644
> --- a/tools/golang/xenlight/xenlight.go
> +++ b/tools/golang/xenlight/xenlight.go
> @@ -216,6 +216,29 @@ func (mac *Mac) toC() (C.libxl_mac, error) {
>  	return cmac, nil
>  }
>  
> +// MsVmGenid represents a libxl_ms_vm_genid.
> +type MsVmGenid [int(C.LIBXL_MS_VM_GENID_LEN)]byte
> +
> +func (mvg *MsVmGenid) fromC(cmvg *C.libxl_ms_vm_genid) error {
> +	b := (*[int(C.LIBXL_MS_VM_GENID_LEN)]C.uint8_t)(unsafe.Pointer(&cmvg.bytes[0]))
> +
> +	for i, v := range b {
> +		mvg[i] = byte(v)
> +	}

It's slightly annoying to have to do this loop, but I guess given that
we have to technically cast each element of the array.  Hopefully the
compiler will eventually be able to figure out what's going on here and
just do a memcpy.

> +
> +	return nil
> +}
> +
> +func (mvg *MsVmGenid) toC() (C.libxl_ms_vm_genid, error) {

Hmm, I guess we want a pointer receiver here to make sure we don't end
up doing a 16-byte copy.

Reviewed-by: George Dunlap <george.dunlap@citrix.com>

 -George
diff mbox series

Patch

diff --git a/tools/golang/xenlight/xenlight.go b/tools/golang/xenlight/xenlight.go
index 3b7824b284..6aca5b89c0 100644
--- a/tools/golang/xenlight/xenlight.go
+++ b/tools/golang/xenlight/xenlight.go
@@ -216,6 +216,29 @@  func (mac *Mac) toC() (C.libxl_mac, error) {
 	return cmac, nil
 }
 
+// MsVmGenid represents a libxl_ms_vm_genid.
+type MsVmGenid [int(C.LIBXL_MS_VM_GENID_LEN)]byte
+
+func (mvg *MsVmGenid) fromC(cmvg *C.libxl_ms_vm_genid) error {
+	b := (*[int(C.LIBXL_MS_VM_GENID_LEN)]C.uint8_t)(unsafe.Pointer(&cmvg.bytes[0]))
+
+	for i, v := range b {
+		mvg[i] = byte(v)
+	}
+
+	return nil
+}
+
+func (mvg *MsVmGenid) toC() (C.libxl_ms_vm_genid, error) {
+	var cmvg C.libxl_ms_vm_genid
+
+	for i, v := range mvg {
+		cmvg.bytes[i] = C.uint8_t(v)
+	}
+
+	return cmvg, nil
+}
+
 type Context struct {
 	ctx    *C.libxl_ctx
 	logger *C.xentoollog_logger_stdiostream