more progress

cg.go

@@ -28,7 +28,7 @@ func NewCgroup(name string) Cgroup {
 	cg := Cgroup{
 		C.cgroup_new_cgroup(C.CString(name)),
 	}
-	runtime.SetFinalizer(cg, freeCgroupThings)
+	runtime.SetFinalizer(&cg, freeCgroupThings)
 	return cg
 }
 
@@ -43,9 +43,10 @@ func (cg Cgroup) GetController(name string) Controller {
 	}
 }
 
-func freeCgroupThings(cg Cgroup) {
-  freeCgroup(cg)
-  freeControllers(cg)
+func freeCgroupThings(cg *Cgroup) {
+
+	freeCgroup(*cg)
+	freeControllers(*cg)
 }
 
 func freeCgroup(cg Cgroup) {
@@ -65,13 +66,202 @@ TODO correct docs for golang implementation
 All parameters set by cgroup_add_value_* functions are written.
 The created groups has owner which was set by cgroup_set_uid_gid() and
 permissions set by cgroup_set_permissions.
+
+  foo = cgroup.NewCgroup("foo)
+  foo.Create()
+
 */
-func CreateGroup(cg Cgroup, ignore_ownership bool) error {
-  var i int = 0
-  if ignore_ownership == true {
-    i = 1
-  }
-  return _err(C.cgroup_create_cgroup(cg.g, C.int(i)))
+func (cg Cgroup) Create() error {
+	return _err(C.cgroup_create_cgroup(cg.g, C.int(0)))
+}
+
+/*
+Same as Create(), but all errors are ignored when setting
+owner of the group and/or its tasks file.
+*/
+func (cg Cgroup) CreateIgnoreOwnership() error {
+	return _err(C.cgroup_create_cgroup(cg.g, C.int(1)))
+}
+
+/*
+Physically create new control group in kernel, with all parameters and values
+copied from its parent group. The group is created in all hierarchies, where
+the parent group exists. I.e. following code creates subgroup in all
+hierarchies, because all of them have root (=parent) group.
+
+  foo = cgroup.NewCgroup("foo)
+  foo.CreateFromParent()
+
+*/
+func (cg Cgroup) CreateFromParent() error {
+	return _err(C.cgroup_create_cgroup_from_parent(cg.g, C.int(0)))
+}
+
+/*
+Same as CreateFromParent(), but all errors are ignored when setting
+owner of the group and/or its tasks file.
+*/
+func (cg Cgroup) CreateFromParentIgnoreOwnership() error {
+	return _err(C.cgroup_create_cgroup_from_parent(cg.g, C.int(1)))
+}
+
+/*
+Physically modify a control group in kernel. All parameters added by
+cgroup_add_value_ or cgroup_set_value_ are written.
+Currently it's not possible to change and owner of a group.
+
+TODO correct docs for golang implementation
+*/
+func (cg Cgroup) Modify() error {
+	return _err(C.cgroup_modify_cgroup(cg.g))
+}
+
+/*
+Physically remove a control group from kernel. The group is removed from
+all hierarchies,  which cover controllers added by Cgroup.AddController()
+or GetCgroup(). All tasks inside the group are automatically moved
+to parent group.
+
+The group being removed must be empty, i.e. without subgroups. Use
+cgroup_delete_cgroup_ext() for recursive delete.
+
+TODO correct docs for golang implementation
+*/
+func (cg Cgroup) Delete() error {
+	return _err(C.cgroup_delete_cgroup(cg.g, C.int(0)))
+}
+
+/*
+Same as Delete(), but ignores errors when migrating.
+*/
+func (cg Cgroup) DeleteIgnoreMigration() error {
+	return _err(C.cgroup_delete_cgroup(cg.g, C.int(1)))
+}
+
+/*
+Physically remove a control group from kernel.
+All tasks are automatically moved to parent group.
+If DeleteIgnoreMigration flag is used, the errors that occurred
+during the task movement are ignored.
+DeleteRecursive flag specifies that all subgroups should be removed
+too. If root group is being removed with this flag specified, all subgroups
+are removed but the root group itself is left undeleted.
+*/
+func (cg Cgroup) DeleteExt(flags DeleteFlag) error {
+	return _err(C.cgroup_delete_cgroup_ext(cg.g, C.int(flags)))
+}
+
+/*
+Read all information regarding the group from kernel.
+Based on name of the group, list of controllers and all parameters and their
+values are read from all hierarchies, where a group with given name exists.
+All existing controllers are replaced. I.e. following code will fill root with
+controllers from all hierarchies, because the root group is available in all of
+them.
+
+  root := cgroup.NewCgroup("/")
+  err := root.Get()
+  ...
+
+*/
+func (cg Cgroup) Get() error {
+	return _err(C.cgroup_get_cgroup(cg.g))
+}
+
+type UID C.uid_t
+type GID C.gid_t
+
+/*
+Set owner of the group control files and the @c tasks file. This function
+modifies only libcgroup internal cgroup structure, use
+Cgroup.Create() afterwards to create the group with given owners.
+
+@param cgroup
+@param tasks_uid UID of the owner of group's @c tasks file.
+@param tasks_gid GID of the owner of group's @c tasks file.
+@param control_uid UID of the owner of group's control files (i.e.
+parameters).
+@param control_gid GID of the owner of group's control files (i.e.
+parameters).
+*/
+func (cg Cgroup) SetUidGid(tasks_uid UID, tasks_gid GID,
+	control_uid UID, control_gid GID) error {
+	return _err(C.cgroup_set_uid_gid(cg.g,
+		C.uid_t(tasks_uid), C.gid_t(tasks_gid),
+		C.uid_t(control_uid), C.gid_t(control_gid)))
+
+}
+
+/*
+Return owners of the group's @c tasks file and control files.
+The data is read from libcgroup internal cgroup structure, use
+Cgroup.SetUidGid() or Cgroup.Get() to fill it.
+*/
+func (cg Cgroup) GetUidGid() (tasks_uid UID, tasks_gid GID, control_uid UID, control_gid GID, err error) {
+	var (
+		c_t_u C.uid_t
+		c_t_g C.gid_t
+		c_c_u C.uid_t
+		c_c_g C.gid_t
+	)
+	err = _err(C.cgroup_set_uid_gid(cg.g,
+		c_t_u,
+		c_t_g,
+		c_c_u,
+		c_c_g))
+	return UID(c_t_u), GID(c_t_g), UID(c_c_u), GID(c_c_g), err
+
+}
+
+const (
+	// Uninitialized file/directory permissions used for task/control files.
+	NO_PERMS = C.NO_PERMS
+
+	// Uninitialized UID/GID used for task/control files.
+	NO_UID_GID = C.NO_UID_GID
+)
+
+type Mode C.mode_t
+
+/*
+Stores given file permissions of the group's control and tasks files
+into the cgroup data structure. Use NO_PERMS if permissions shouldn't
+be changed or a value which applicable to chmod(2). Please note that
+the given permissions are masked with the file owner's permissions.
+For example if a control file has permissions 640 and control_fperm is
+471 the result will be 460.
+
+control_dperm Directory permission for the group.
+control_fperm File permission for the control files.
+task_fperm File permissions for task file.
+
+  g := cgroup.NewCgroup("foo")
+  g.SetPermissions(cgroup.Mode(0777), cgroup.Mode(0777), cgroup.Mode(0777))
+*/
+func (cg Cgroup) SetPermissions(control_dperm, control_fperm, task_fperm Mode) {
+	C.cgroup_set_permissions(cg.g, C.mode_t(control_dperm),
+		C.mode_t(control_fperm), C.mode_t(task_fperm))
+}
+
+/*
+Copy all controllers, parameters and their values. All existing controllers
+in the source group are discarded.
+*/
+func CopyCgroup(src, dest Cgroup) error {
+	return _err(C.cgroup_copy_cgroup(src.g, dest.g))
+}
+
+/*
+Compare names, owners, controllers, parameters and values of two groups.
+
+Return value of:
+ * nil - a and b are equal
+ * ECGROUPNOTEQUAL - groups are not equal
+ * ECGCONTROLLERNOTEQUAL - controllers are not equal
+
+*/
+func CompareCgroup(a, b Cgroup) error {
+	return _err(C.cgroup_compare_cgroup(a.g, b.g))
 }
 
 /*
@@ -83,6 +273,27 @@ type Controller struct {
 	c *C.struct_cgroup_controller
 }
 
+/*
+Add parameter and its value to internal libcgroup structures.
+Use Cgroup.Modify() or Cgroup.Create() to write it to kernel.
+
+Name of the parameter and its value
+*/
+func (c Controller) AddValueString(name, value string) error {
+	return _err(C.cgroup_add_value_string(c.c, C.CString(name), C.CString(value)))
+}
+
+/*
+Compare names, parameters and values of two controllers.
+
+Return value of:
+ * nil - a and b are equal
+ * ECGCONTROLLERNOTEQUAL - controllers are not equal
+*/
+func CompareControllers(a, b Controller) error {
+	return _err(C.cgroup_compare_controllers(a.c, b.c))
+}
+
 /*
 Initialize libcgroup. Information about mounted hierarchies are examined
 and cached internally (just what's mounted where, not the groups themselves).
@@ -154,7 +365,7 @@ New default permissions from this group are copied to libcgroup internal
 structures.
 */
 func SetDefault(cg Cgroup) error {
-  return _err(C.cgroup_config_set_default(cg.g))
+	return _err(C.cgroup_config_set_default(cg.g))
 }
 
 type FileInfo struct {
@@ -244,8 +455,10 @@ func GetSubSysMountPoint(controller string) (string, error) {
 
 var (
 	// End-of-file for iterators
-	ECGEOF   = errors.New(C.GoString(C.cgroup_strerror(C.ECGEOF)))
-	ECGOTHER = errors.New(C.GoString(C.cgroup_strerror(C.ECGOTHER)))
+	ECGEOF                = errors.New(C.GoString(C.cgroup_strerror(C.ECGEOF)))
+	ECGOTHER              = errors.New(C.GoString(C.cgroup_strerror(C.ECGOTHER)))
+	ECGROUPNOTEQUAL       = errors.New(C.GoString(C.cgroup_strerror(C.ECGROUPNOTEQUAL)))
+	ECGCONTROLLERNOTEQUAL = errors.New(C.GoString(C.cgroup_strerror(C.ECGCONTROLLERNOTEQUAL)))
 )
 
 /*
@@ -263,6 +476,10 @@ func _err(num C.int) error {
 		return ECGEOF
 	case C.ECGOTHER:
 		return ECGOTHER
+	case C.ECGROUPNOTEQUAL:
+		return ECGROUPNOTEQUAL
+	case C.ECGCONTROLLERNOTEQUAL:
+		return ECGCONTROLLERNOTEQUAL
 	}
 	// There's a lot. We'll create them as they come
 	return errors.New(C.GoString(C.cgroup_strerror(num)))