golang/xenlight: re-factor Hwcap type implementation

Re-define Hwcap as [8]uint32, and implement toC function. Also, re-name and
modify signature of toGo function to fromC.

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>

diff --git a/tools/golang/xenlight/xenlight.go b/tools/golang/xenlight/xenlight.go
index f9c2f84c81cd89ad905cb2620048e04928713be4..b395963512669e9a9e7a17ec49d0caa7d0d97852 100644 (file)
--- a/tools/golang/xenlight/xenlight.go
+++ b/tools/golang/xenlight/xenlight.go
@@ -306,20 +306,25 @@ type Context struct {
        logger *C.xentoollog_logger_stdiostream
 }
 
-type Hwcap []C.uint32_t
+// Hwcap represents a libxl_hwcap.
+type Hwcap [8]uint32
 
-func (chwcap C.libxl_hwcap) toGo() (ghwcap Hwcap) {
-       // Alloc a Go slice for the bytes
-       size := 8
-       ghwcap = make([]C.uint32_t, size)
+func (hwcap *Hwcap) fromC(chwcap *C.libxl_hwcap) error {
+       for i := range *hwcap {
+               hwcap[i] = uint32(chwcap[i])
+       }
 
-       // Make a slice pointing to the C array
-       mapslice := (*[1 << 30]C.uint32_t)(unsafe.Pointer(&chwcap[0]))[:size:size]
+       return nil
+}
 
-       // And copy the C array into the Go array
-       copy(ghwcap, mapslice)
+func (hwcap *Hwcap) toC() (C.libxl_hwcap, error) {
+       var chwcap C.libxl_hwcap
 
-       return
+       for i, v := range hwcap {
+               chwcap[i] = C.uint32_t(v)
+       }
+
+       return chwcap, nil
 }
 
 // KeyValueList represents a libxl_key_value_list.
@@ -442,7 +447,7 @@ func (cphys *C.libxl_physinfo) toGo() (physinfo *Physinfo) {
        physinfo.SharingFreedPages = uint64(cphys.sharing_freed_pages)
        physinfo.SharingUsedFrames = uint64(cphys.sharing_used_frames)
        physinfo.NrNodes = uint32(cphys.nr_nodes)
-       physinfo.HwCap = cphys.hw_cap.toGo()
+       physinfo.HwCap.fromC(&cphys.hw_cap)
        physinfo.CapHvm = bool(cphys.cap_hvm)
        physinfo.CapHvmDirectio = bool(cphys.cap_hvm_directio)