rados: add support for object locking + test

This commit is contained in:
Emmet Cassidy 2016-08-03 15:50:34 -07:00 committed by Michael Andersen
parent b900b94822
commit 628bae93d1
2 changed files with 320 additions and 2 deletions

View File

@ -4,10 +4,20 @@ package rados
// #include <errno.h>
// #include <stdlib.h>
// #include <rados/librados.h>
//
// char* nextChunk(char **idx) {
// char *copy;
// copy = strdup(*idx);
// *idx += strlen(*idx) + 1;
// return copy;
// }
import "C"
import "unsafe"
import "time"
import (
"syscall"
"time"
"unsafe"
)
// PoolStat represents Ceph pool statistics.
type PoolStat struct {
@ -41,6 +51,16 @@ type ObjectStat struct {
ModTime time.Time
}
// LockInfo represents information on a current Ceph lock
type LockInfo struct {
NumLockers int
Exclusive bool
Tag string
Clients []string
Cookies []string
Addrs []string
}
// IOContext represents a context for performing I/O within a pool.
type IOContext struct {
ioctx C.rados_ioctx_t
@ -619,3 +639,223 @@ func (iter *Iter) Err() error {
func (iter *Iter) Close() {
C.rados_objects_list_close(iter.ctx)
}
// Take an exclusive lock on an object.
func (ioctx *IOContext) LockExclusive(oid, name, cookie, desc string, duration time.Duration, flags *byte) (int, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_cookie := C.CString(cookie)
c_desc := C.CString(desc)
var c_duration C.struct_timeval
if duration != 0 {
tv := syscall.NsecToTimeval(time.Now().Add(duration).UnixNano())
c_duration = C.struct_timeval{tv_sec: C.__time_t(tv.Sec), tv_usec: C.__suseconds_t(tv.Usec)}
}
var c_flags C.uint8_t
if flags != nil {
c_flags = C.uint8_t(*flags)
}
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_cookie))
defer C.free(unsafe.Pointer(c_desc))
ret := C.rados_lock_exclusive(
ioctx.ioctx,
c_oid,
c_name,
c_cookie,
c_desc,
&c_duration,
c_flags)
// 0 on success, negative error code on failure
// -EBUSY if the lock is already held by another (client, cookie) pair
// -EEXIST if the lock is already held by the same (client, cookie) pair
switch ret {
case 0:
return int(ret), nil
case -16: // EBUSY
return int(ret), nil
case -17: // EEXIST
return int(ret), nil
default:
return int(ret), RadosError(int(ret))
}
}
// Take a shared lock on an object.
func (ioctx *IOContext) LockShared(oid, name, cookie, tag, desc string, duration time.Duration, flags *byte) (int, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_cookie := C.CString(cookie)
c_tag := C.CString(tag)
c_desc := C.CString(desc)
var c_duration C.struct_timeval
if duration != 0 {
tv := syscall.NsecToTimeval(time.Now().Add(duration).UnixNano())
c_duration = C.struct_timeval{tv_sec: C.__time_t(tv.Sec), tv_usec: C.__suseconds_t(tv.Usec)}
}
var c_flags C.uint8_t
if flags != nil {
c_flags = C.uint8_t(*flags)
}
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_cookie))
defer C.free(unsafe.Pointer(c_tag))
defer C.free(unsafe.Pointer(c_desc))
ret := C.rados_lock_shared(
ioctx.ioctx,
c_oid,
c_name,
c_cookie,
c_tag,
c_desc,
&c_duration,
c_flags)
// 0 on success, negative error code on failure
// -EBUSY if the lock is already held by another (client, cookie) pair
// -EEXIST if the lock is already held by the same (client, cookie) pair
switch ret {
case 0:
return int(ret), nil
case -16: // EBUSY
return int(ret), nil
case -17: // EEXIST
return int(ret), nil
default:
return int(ret), RadosError(int(ret))
}
}
// Release a shared or exclusive lock on an object.
func (ioctx *IOContext) Unlock(oid, name, cookie string) (int, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_cookie := C.CString(cookie)
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_cookie))
// 0 on success, negative error code on failure
// -ENOENT if the lock is not held by the specified (client, cookie) pair
ret := C.rados_unlock(
ioctx.ioctx,
c_oid,
c_name,
c_cookie)
switch ret {
case 0:
return int(ret), nil
case -2: // -ENOENT
return int(ret), nil
default:
return int(ret), RadosError(int(ret))
}
}
// List clients that have locked the named object lock and information about the lock.
// The number of bytes required in each buffer is put in the corresponding size out parameter.
// If any of the provided buffers are too short, -ERANGE is returned after these sizes are filled in.
func (ioctx *IOContext) ListLockers(oid, name string) (*LockInfo, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_tag := (*C.char)(C.malloc(C.size_t(1024)))
c_clients := (*C.char)(C.malloc(C.size_t(1024)))
c_cookies := (*C.char)(C.malloc(C.size_t(1024)))
c_addrs := (*C.char)(C.malloc(C.size_t(1024)))
var c_exclusive C.int
c_tag_len := C.size_t(1024)
c_clients_len := C.size_t(1024)
c_cookies_len := C.size_t(1024)
c_addrs_len := C.size_t(1024)
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_tag))
defer C.free(unsafe.Pointer(c_clients))
defer C.free(unsafe.Pointer(c_cookies))
defer C.free(unsafe.Pointer(c_addrs))
ret := C.rados_list_lockers(
ioctx.ioctx,
c_oid,
c_name,
&c_exclusive,
c_tag,
&c_tag_len,
c_clients,
&c_clients_len,
c_cookies,
&c_cookies_len,
c_addrs,
&c_addrs_len)
splitCString := func(items *C.char, itemsLen C.size_t) []string {
currLen := 0
clients := []string{}
for currLen < int(itemsLen) {
client := C.GoString(C.nextChunk(&items))
clients = append(clients, client)
currLen += len(client) + 1
}
return clients
}
if ret < 0 {
return nil, RadosError(int(ret))
} else {
return &LockInfo{int(ret), c_exclusive == 1, C.GoString(c_tag), splitCString(c_clients, c_clients_len), splitCString(c_cookies, c_cookies_len), splitCString(c_addrs, c_addrs_len)}, nil
}
}
// Releases a shared or exclusive lock on an object, which was taken by the specified client.
func (ioctx *IOContext) BreakLock(oid, name, client, cookie string) (int, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_client := C.CString(client)
c_cookie := C.CString(cookie)
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_client))
defer C.free(unsafe.Pointer(c_cookie))
// 0 on success, negative error code on failure
// -ENOENT if the lock is not held by the specified (client, cookie) pair
// -EINVAL if the client cannot be parsed
ret := C.rados_break_lock(
ioctx.ioctx,
c_oid,
c_name,
c_client,
c_cookie)
switch ret {
case 0:
return int(ret), nil
case -2: // -ENOENT
return int(ret), nil
case -22: // -EINVAL
return int(ret), nil
default:
return int(ret), RadosError(int(ret))
}
}

View File

@ -901,3 +901,81 @@ func TestSetNamespace(t *testing.T) {
pool.Destroy()
conn.Shutdown()
}
func TestLocking(t *testing.T) {
conn, _ := rados.NewConn()
conn.ReadDefaultConfigFile()
conn.Connect()
pool_name := GetUUID()
err := conn.MakePool(pool_name)
assert.NoError(t, err)
pool, err := conn.OpenIOContext(pool_name)
assert.NoError(t, err)
// lock ex
res, err := pool.LockExclusive("obj", "myLock", "myCookie", "this is a test lock", 0, nil)
assert.NoError(t, err)
assert.Equal(t, 0, res)
// verify lock ex
info, err := pool.ListLockers("obj", "myLock")
assert.NoError(t, err)
assert.Equal(t, 1, len(info.Clients))
assert.Equal(t, true, info.Exclusive)
// fail to lock ex again
res, err = pool.LockExclusive("obj", "myLock", "myCookie", "this is a description", 0, nil)
assert.NoError(t, err)
assert.Equal(t, -17, res)
// fail to lock sh
res, err = pool.LockShared("obj", "myLock", "myCookie", "", "a description", 0, nil)
assert.NoError(t, err)
assert.Equal(t, -17, res)
// unlock
res, err = pool.Unlock("obj", "myLock", "myCookie")
assert.NoError(t, err)
assert.Equal(t, 0, res)
// verify unlock
info, err = pool.ListLockers("obj", "myLock")
assert.NoError(t, err)
assert.Equal(t, 0, len(info.Clients))
// lock sh
res, err = pool.LockShared("obj", "myLock", "myCookie", "", "a description", 0, nil)
assert.NoError(t, err)
assert.Equal(t, 0, res)
// verify lock sh
info, err = pool.ListLockers("obj", "myLock")
assert.NoError(t, err)
assert.Equal(t, 1, len(info.Clients))
assert.Equal(t, false, info.Exclusive)
// fail to lock sh again
res, err = pool.LockExclusive("obj", "myLock", "myCookie", "a description", 0, nil)
assert.NoError(t, err)
assert.Equal(t, -17, res)
// fail to lock ex
res, err = pool.LockExclusive("obj", "myLock", "myCookie", "this is a test lock", 0, nil)
assert.NoError(t, err)
assert.Equal(t, res, -17)
// break the lock
res, err = pool.BreakLock("obj", "myLock", info.Clients[0], "myCookie")
assert.NoError(t, err)
assert.Equal(t, 0, res)
// verify lock broken
info, err = pool.ListLockers("obj", "myLock")
assert.NoError(t, err)
assert.Equal(t, 0, len(info.Clients))
pool.Destroy()
conn.Shutdown()
}