| Message ID | 20200117155734.1067550-2-george.dunlap@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3,1/8] golang/xenlight: Don't try to marshall zero-length arrays in fromC | expand |
> Empty Go strings should be converted to `nil` libxl_cpuid_policy_list; > otherwise libxl_cpuid_parse_config gets confused. > > Also, libxl_cpuid_policy_list returns a weird error, not a "normal" > libxl error; if it returns one of these non-standard errors, convert > it to ErrorInval. > > Finally, make the fromC() method take a pointer, and set the value of > CpuidPolicyList such that it will generate a valid CpuidPolicyList in > response. > > Signed-off-by: George Dunlap <george.dunlap@citrix.com> Reviewed-by: Nick Rosbrook <rosbrookn@ainfosec.com>
diff --git a/tools/golang/xenlight/xenlight.go b/tools/golang/xenlight/xenlight.go index b1587b964f..1299981713 100644 --- a/tools/golang/xenlight/xenlight.go +++ b/tools/golang/xenlight/xenlight.go @@ -306,9 +306,14 @@ func (el *EvLink) toC(cel *C.libxl_ev_link) (err error) { return } // empty when it is returned from libxl. type CpuidPolicyList string -func (cpl CpuidPolicyList) fromC(ccpl *C.libxl_cpuid_policy_list) error { return nil } +func (cpl *CpuidPolicyList) fromC(ccpl *C.libxl_cpuid_policy_list) error { *cpl = ""; return nil } func (cpl CpuidPolicyList) toC(ccpl *C.libxl_cpuid_policy_list) error { + if cpl == "" { + *ccpl = nil + return nil + } + s := C.CString(string(cpl)) defer C.free(unsafe.Pointer(s)) @@ -316,7 +321,8 @@ func (cpl CpuidPolicyList) toC(ccpl *C.libxl_cpuid_policy_list) error { if ret != 0 { C.libxl_cpuid_dispose(ccpl) - return Error(-ret) + // libxl_cpuid_parse_config doesn't return a normal libxl error. + return ErrorInval } return nil
Empty Go strings should be converted to `nil` libxl_cpuid_policy_list; otherwise libxl_cpuid_parse_config gets confused. Also, libxl_cpuid_policy_list returns a weird error, not a "normal" libxl error; if it returns one of these non-standard errors, convert it to ErrorInval. Finally, make the fromC() method take a pointer, and set the value of CpuidPolicyList such that it will generate a valid CpuidPolicyList in response. Signed-off-by: George Dunlap <george.dunlap@citrix.com> --- v2: - Port over toC() function signature change - Have fromC set the string to "" CC: Nick Rosbrook <rosbrookn@ainfosec.com> --- tools/golang/xenlight/xenlight.go | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)