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cg: halfway to golint

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This commit is contained in:
Vincent Batts 2016-11-29 10:06:09 -05:00
parent c2855cec9b
commit 727ac7a93b
1 changed files with 116 additions and 111 deletions
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227
cg.go
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@ -16,10 +16,8 @@ import (
"unsafe"
)
/*
Structure describing one or more control groups. The structure is opaque to
applications.
*/
// Cgroup is the structure describing one or more control groups. The structure
// is opaque to applications.
type Cgroup struct {
g *C.struct_cgroup
}
@ -117,7 +115,7 @@ func (cg Cgroup) Modify() error {
}
/*
Physically remove a control group from kernel. The group is removed from
Delete removes 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.
@ -132,14 +130,14 @@ func (cg Cgroup) Delete() error {
}
/*
Same as Delete(), but ignores errors when migrating.
DeleteIgnoreMigration is the 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.
DeleteExt removes 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.
@ -152,7 +150,7 @@ func (cg Cgroup) DeleteExt(flags DeleteFlag) error {
}
/*
Read all information regarding the group from kernel.
Get reads 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
@ -168,48 +166,48 @@ func (cg Cgroup) Get() error {
return _err(C.cgroup_get_cgroup(cg.g))
}
type UID C.uid_t
type GID C.gid_t
type (
UID C.uid_t
GID C.gid_t
)
/*
Set owner of the group control files and the @c tasks file. This function
SetUIDGID sets 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.
@param tasksUID UID of the owner of group's @c tasks file.
@param tasksGID GID of the owner of group's @c tasks file.
@param controlUID 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.
@param controlGID 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 {
func (cg Cgroup) SetUIDGID(tasksUID UID, tasksGID GID,
controlUID UID, controlGID 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)))
C.uid_t(tasksUID), C.gid_t(tasksGID),
C.uid_t(controlUID), C.gid_t(controlGID)))
}
/*
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) {
// GetUIDGID returns 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() (tasksUID UID, tasksGID GID, controlUID UID, controlGID 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
cTU C.uid_t
cTG C.gid_t
cCU C.uid_t
cCG 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
cTU,
cTG,
cCU,
cCG))
return UID(cTU), GID(cTG), UID(cCU), GID(cCG), err
}
@ -224,7 +222,7 @@ const (
type Mode C.mode_t
/*
Stores given file permissions of the group's control and tasks files
SetPermissions 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.
@ -243,42 +241,33 @@ func (cg Cgroup) SetPermissions(control_dperm, control_fperm, task_fperm Mode) {
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.
*/
// CopyCgroup copies 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
*/
// CompareCgroup compares names, owners, controllers, parameters and values of two groups.
//
// Return value of:
// * nil - a and b are equal
// * ErrGroupNotEqual - groups are not equal
// * ErrControllerNotEqual - controllers are not equal
func CompareCgroup(a, b Cgroup) error {
return _err(C.cgroup_compare_cgroup(a.g, b.g))
}
/*
Structure describing a controller attached to one struct @c cgroup, including
parameters of the group and their values. The structure is opaque to
applications.
*/
// Controller is the structure describing a controller attached to one struct
// @c cgroup, including parameters of the group and their values. The structure
// is opaque to applications.
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
*/
// AddValueString adds 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)))
}
@ -291,9 +280,8 @@ func (c Controller) AddValueBool(name string, value bool) error {
return _err(C.cgroup_add_value_bool(c.c, C.CString(name), C.bool(value)))
}
/*
Use Cgroup.Get() to fill these values with data from the kernel
*/
// GetValueString fetches the values from the controller. Use Cgroup.Get() to
// get the names available to fetch values from the kernel.
func (c Controller) GetValueString(name string) (value string, err error) {
var v *C.char
err = _err(C.cgroup_get_value_string(c.c, C.CString(name), &v))
@ -333,35 +321,30 @@ func (c Controller) SetValueBool(name string, value bool) error {
}
/*
Compare names, parameters and values of two controllers.
CompareControllers compares names, parameters and values of two controllers.
Return value of:
* nil - a and b are equal
* ECGCONTROLLERNOTEQUAL - controllers are not equal
* ErrControllerNotEqual - 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).
*/
// Init initializes libcgroup. Information about mounted hierarchies are
// examined and cached internally (just what's mounted where, not the groups
// themselves).
func Init() error {
return _err(C.cgroup_init())
}
/*
Load configuration file and mount and create control groups described there.
See cgconfig.conf man page for format of the file.
*/
// LoadConfig file and mount and create control groups described there.
// See cgconfig.conf(5) man page for format of the file.
func LoadConfig(filename string) error {
return _err(C.cgroup_config_load_config(C.CString(filename)))
}
/*
Delete all control groups and unmount all hierarchies.
*/
// Unload deletes all control groups and unmount all hierarchies.
func Unload() error {
return _err(C.cgroup_unload_cgroups())
}
@ -369,27 +352,25 @@ func Unload() error {
type DeleteFlag int
const (
// Ignore errors caused by migration of tasks to parent group.
// DeleteIgnoreMigration ignore errors caused by migration of tasks to parent group.
DeleteIgnoreMigration = DeleteFlag(C.CGFLAG_DELETE_IGNORE_MIGRATION)
// Recursively delete all child groups.
// DeleteRecursive recursively delete all child groups.
DeleteRecursive = DeleteFlag(C.CGFLAG_DELETE_RECURSIVE)
/*
Delete the cgroup only if it is empty, i.e. it has no subgroups and
no processes inside. This flag cannot be used with
DeleteRecursive
*/
// DeleteEmptyOnly deletes the cgroup only if it is empty, i.e. it has no
// subgroups and no processes inside. This flag cannot be used with
// DeleteRecursive
DeleteEmptyOnly = DeleteFlag(C.CGFLAG_DELETE_EMPTY_ONLY)
)
/*
Delete all cgroups and unmount all mount points defined in specified config
file.
UnloadFromConfig deletes all cgroups and unmount all mount points defined in
specified config file.
The groups are either removed recursively or only the empty ones, based
on given flags. Mount point are always umounted only if they are empty,
regardless of any flags.
The groups are either removed recursively or only the empty ones, based on
given flags. Mount point are always umounted only if they are empty, regardless
of any flags.
The groups are sorted before they are removed, so the removal of empty ones
actually works (i.e. subgroups are removed first).
@ -399,7 +380,7 @@ func UnloadFromConfig(filename string, flags DeleteFlag) error {
}
/*
Sets default permissions of groups created by subsequent
SetDefault permissions of groups created by subsequent
cgroup_config_load_config() calls. If a config file contains a 'default {}'
section, the default permissions from the config file is then used.
@ -417,21 +398,47 @@ func SetDefault(cg Cgroup) error {
return _err(C.cgroup_config_set_default(cg.g))
}
// FileInfo is the Information about found cgroup directory (= a control group).
type FileInfo struct {
Type FileType
Path string
Parent string
FullPath string
Depth int8
fileType FileType
path string
parent string
fullPath string
depth int8
}
// FileType of this cgroup's
func (fi FileInfo) FileType() FileType {
return fi.fileType
}
// Path to this cgroup
func (fi FileInfo) Path() string {
return fi.path
}
// Parent of this cgroup
func (fi FileInfo) Parent() string {
return fi.parent
}
// FullPath to this cgroup
func (fi FileInfo) FullPath() string {
return fi.fullPath
}
// Depth of this cgroup
func (fi FileInfo) Depth() int8 {
return fi.depth
}
func fromCFileInfo(cData C.struct_cgroup_file_info) FileInfo {
return FileInfo{
Type: FileType(C.type_from_file_info(cData)),
Path: C.GoString(cData.path),
Parent: C.GoString(cData.parent),
FullPath: C.GoString(cData.full_path),
Depth: int8(cData.depth),
fileType: FileType(C.type_from_file_info(cData)),
path: C.GoString(cData.path),
parent: C.GoString(cData.parent),
fullPath: C.GoString(cData.full_path),
depth: int8(cData.depth),
}
}
@ -503,7 +510,7 @@ func GetAllControllers() (controllers []ControllerData, err error) {
for {
err = _err(C.cgroup_get_all_controller_next(&handle, &cd))
if err != nil {
if err == ECGEOF {
if err == ErrEOF {
break
}
@ -524,17 +531,15 @@ func GetSubSysMountPoint(controller string) (string, error) {
return C.GoString(mp), nil
}
// Various errors
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)))
ECGROUPNOTEQUAL = errors.New(C.GoString(C.cgroup_strerror(C.ECGROUPNOTEQUAL)))
ECGCONTROLLERNOTEQUAL = errors.New(C.GoString(C.cgroup_strerror(C.ECGCONTROLLERNOTEQUAL)))
ErrEOF = errors.New(C.GoString(C.cgroup_strerror(C.ECGEOF)))
ErrOTHER = errors.New(C.GoString(C.cgroup_strerror(C.ECGOTHER)))
ErrGroupNotEqual = errors.New(C.GoString(C.cgroup_strerror(C.ECGROUPNOTEQUAL)))
ErrControllerNotEqual = errors.New(C.GoString(C.cgroup_strerror(C.ECGCONTROLLERNOTEQUAL)))
)
/*
Return last errno, which caused ECGOTHER error.
*/
// LastError returns last errno, which caused ErrOTHER error.
func LastError() error {
return _err(C.cgroup_get_last_errno())
}
@ -544,13 +549,13 @@ func _err(num C.int) error {
case 0:
return nil
case C.ECGEOF:
return ECGEOF
return ErrEOF
case C.ECGOTHER:
return ECGOTHER
return ErrOTHER
case C.ECGROUPNOTEQUAL:
return ECGROUPNOTEQUAL
return ErrGroupNotEqual
case C.ECGCONTROLLERNOTEQUAL:
return ECGCONTROLLERNOTEQUAL
return ErrControllerNotEqual
}
// There's a lot. We'll create them as they come
return errors.New(C.GoString(C.cgroup_strerror(num)))