[03/24] golang/xenlight: define Defbool builtin type
diff mbox series

Message ID 00b468deae50cb125be01ff90ceb739fd25f8e5c.1570456846.git.rosbrookn@ainfosec.com
State Superseded
Headers show
Series
  • generated Go libxl bindings using IDL
Related show

Commit Message

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

Define Defbool as struct analagous to the C type, and define the type
'defboolVal' that represent true, false, and default defbool values.

Implement Set, Unset, SetIfDefault, IsDefault, Val, and String functions
on Defbool so that the type can be used in Go analagously to how its
used in C.

Finally, 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 | 93 +++++++++++++++++++++++++++++++
 1 file changed, 93 insertions(+)

Comments

George Dunlap Oct. 24, 2019, 3:17 p.m. UTC | #1
On 10/7/19 4:12 PM, Nick Rosbrook wrote:
> From: Nick Rosbrook <rosbrookn@ainfosec.com>
> 
> Define Defbool as struct analagous to the C type, and define the type
> 'defboolVal' that represent true, false, and default defbool values.
> 
> Implement Set, Unset, SetIfDefault, IsDefault, Val, and String functions
> on Defbool so that the type can be used in Go analagously to how its
> used in C.
> 
> Finally, implement fromC and toC functions.
> 
> Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>

Looks good:

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

Patch
diff mbox series

diff --git a/tools/golang/xenlight/xenlight.go b/tools/golang/xenlight/xenlight.go
index e617f22fcf..7bf16dc03b 100644
--- a/tools/golang/xenlight/xenlight.go
+++ b/tools/golang/xenlight/xenlight.go
@@ -85,6 +85,99 @@  type MemKB uint64
 
 type Uuid C.libxl_uuid
 
+// defboolVal represents a defbool value.
+type defboolVal int
+
+const (
+	defboolDefault defboolVal = 0
+	defboolFalse   defboolVal = -1
+	defboolTrue    defboolVal = 1
+)
+
+// Defbool represents a libxl_defbool.
+type Defbool struct {
+	val defboolVal
+}
+
+func (d Defbool) String() string {
+	switch d.val {
+	case defboolDefault:
+		return "<default>"
+	case defboolFalse:
+		return "False"
+	case defboolTrue:
+		return "True"
+	}
+
+	return ""
+}
+
+// Set sets the value of the Defbool.
+func (d *Defbool) Set(b bool) {
+	if b {
+		d.val = defboolTrue
+		return
+	}
+	d.val = defboolFalse
+}
+
+// Unset resets the Defbool to default value.
+func (d *Defbool) Unset() {
+	d.val = defboolDefault
+}
+
+// SetIfDefault sets the value of Defbool only if
+// its current value is default.
+func (d *Defbool) SetIfDefault(b bool) {
+	if d.IsDefault() {
+		d.Set(b)
+	}
+}
+
+// IsDefault returns true if the value of Defbool
+// is default, returns false otherwise.
+func (d *Defbool) IsDefault() bool {
+	return d.val == defboolDefault
+}
+
+// Val returns the boolean value associated with the
+// Defbool value. An error is returned if the value
+// is default.
+func (d *Defbool) Val() (bool, error) {
+	if d.IsDefault() {
+		return false, fmt.Errorf("%v: cannot take value of default defbool", ErrorInval)
+	}
+
+	return (d.val > 0), nil
+}
+
+func (d *Defbool) fromC(c *C.libxl_defbool) error {
+	if C.libxl_defbool_is_default(*c) {
+		d.val = defboolDefault
+		return nil
+	}
+
+	if C.libxl_defbool_val(*c) {
+		d.val = defboolTrue
+		return nil
+	}
+
+	d.val = defboolFalse
+
+	return nil
+}
+
+func (d *Defbool) toC() (C.libxl_defbool, error) {
+	var c C.libxl_defbool
+
+	if !d.IsDefault() {
+		val, _ := d.Val()
+		C.libxl_defbool_set(&c, C.bool(val))
+	}
+
+	return c, nil
+}
+
 type Context struct {
 	ctx    *C.libxl_ctx
 	logger *C.xentoollog_logger_stdiostream